PeTI (Perpetual Testing Initiative) the creation environment integrated into Portal 2, is ergonomic enough to allow you to create a test room very quickly.
But to go further, you need to know the possibilities, more or less hidden and desired, and the limitations of this tool, in order to create interesting and "well defined" rooms.

I try to gather here all the "tips and tricks" found to allow beginners to progress, and make more interesting maps and if possible without defects.

This guide covers the room editor, Puzzle Maker, in design, or in conception mode, but also behaviors in test mode, "first-person puzzle preview" (as in the map being tested by players). It presents different aspects and techniques to help you discover the full potential of this game.
Portal 2 has a two-player co-op mode; it won't be covered here as I've never explored it.
Because portal mechanics are complex, all the interaction issues with the environment, the player, and various fixed or moving objects would be too difficult for developers to solve. This leads to the presence of flaws that can circumvent the intended solution of the test; these are called glitches.
See this showroom: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=309614372
And this one using BEEMOD2 (see Mods chapter at the end of this guide): https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=658177034
I update this guide as I make discoveries and reflect on it, taking into account your comments (five major updates have already been made).

Some terms used for convenience:

• Map = card, puzzle, chamber or testing room, in short ;o)
  
• Glitch = anomaly, small bug not crashing the game, but having more or less of consequences for the progress of the play.
  
• Fizzler = disintegrating barrier item (see section Energy items).
  
• Funnel = tractor beam (see section Energy items (2)).

(the menus of the editor do not tell everything!)

• A, D = right click+movement = Shift+left click+movement: move the scene.
  
• Q, E and R, F = left click out of the scene+movement = mouse wheel button+movement: rotate the scene.
  
• H = Home: reset the camera of the scene.
  
• W, S = Ctrl+mouse wheel: zoom the scene centered on screen.
  
• mouse wheel: zoom centered on the mouse pointer position.
  
• Space+click+movement = Enter = +, -: sink in or extrudes the selected surface. If it is the 3D block which is selected, see farther.
  
• Delete = Back space: delete selected items.
  
• Escape: cancel all selection, or if there is not, open the exit and options menu.
  
• Arrows: move the selection mark in the arrows direction.
  
• Arrows+ Shift or Alt: enlarge the selection.
  
• Page up/down: move the selection mark in front/back.
  
• Double click: select all the surface in the same plan as the selected square.
  
• Alt: activate hidden walls (blocking the sight camera) to enable item placement.
  
• O = Alt+P: invert the state of portalability of selected squares.
  
• P: makes non-portalable the selected squares if at least one it is already, otherwise makes them all portalable.
  
• ': makes portalable all selected squares.
  
• Opening bracket: makes non portalable all selected squares.
  These last two keys are situated top/right of P. They may differ on a non QWERTY keyboard.
  
• K: connect the item selected with the one clicked then.
  Glitch: this key initializes the connection from any object, even those not connectable as the faith plate or the glass panel (but without finding a valuable target)!
  
• C = Ctrl+D if item selected, = Ctrl+click on item: make a copy of the item.
  Glitch: these keys allow to copy even doors and big observation room! (See section Automatic elements)
  
• Shift+click on wall: select the rectangle (or 3D block, see farther) made by the clicked square and the existing selection.
  
• Shift+click on the rotation sign of a turret or a cube (without dropper)+movement: turn by 1/8 of tour.
  
• Tab: switch from the publishing mode to the test mode (says "contextual view") and conversely.
  
• Shift+Tab: switch between the editor and the screen of workshop and conversely.
  
• Ctrl+A: select all
  
• Ctrl+N: create a new map
  
• Ctrl+O: open a map
  
• Ctrl+Q: quit
  
• Ctrl+S: save the present map
  
• Ctrl+Shift+S: save the map with a new name
  
• Ctrl+Y: redo the last action
  
• Ctrl+Z: cancel the last action
  
• F9: generate the map and launch the test mode
  
• Shift+F2: demos management (see section Advice and publication).

There is also a key to make a screen shot and one to enter the console commands (see at the end of this guide) which are customisable.

During the game (with subscribed map, do not work in test mode):

• F6: save (checkpoint) in case of death, for not to restart everything.
  
• F7: restart from the checkpoint.

This possibility is kept between the playing sessions, we can thus make a long map in several times.

(3D blocks)
A block of selection is a set of marked elements of the map, in three dimensions. We realize it by sliding the mouse after having clicked a corner of the selection, up to the opposite corner, or by making a click then a Shift+click on each extremity. We can then rectify the volume via the yellow balls marking corners.
As with the selections of surface, we can then use certain keys:
Delete = -: clear the block.
+: fill it with wall.
P and others...
But the main utility of these blocks is the transfer of a piece of room. For that purpose, make slide the block with the mouse according to one of the 3D axes while pressing on Space.
Regret: we cannot unfortunately rotate these blocks or copy them.
Glitch: a cube dropper attached to the ceiling does not move, or moves twice more! The rails of platform are reduced to a length of one square. However, we can then replace correctly these elements.

In the editor, we can configure nothing about these portals; unless we install a mod (see Mods chapter at the end of this guide), BEEMOD AutoPortal for example. Everything in this section thus concerns the "testing" mode (map running).
The tool the player (represented by Bendy, see opposite) possesses upon entering a map is a portal gun, Aperture Science Handheld Portal Device. It allows you to create two portals, each of which has a different color to better distinguish them, but which function in the same way; there isn't one reserved for entering and the other for exiting (there are four colors in two-player co-op mode).
See a detailed description of the gun: ASHPD[half-life.fandom.com]


A reticule formed by two half-moons with five dots inside indicates the place where we fire (see opposite).
After the shooting, the half-reticule and a light over the pistol take the color of the last created portal.
The gun also allows you to act (at short distance) on items: press on a pedestal button, catch a free object (cube, turret, placed or flying) even through a grating.
You can fire a portal through a cube, a grating, a light bridge or a laser field, but not through a glass panel, a fizzler or an other portal.
A portal can only be made on a surface (called portalable) only if it is white, flat and sufficiently large.
A "ghost" indicates the presence of one or two portals in the map (for visual reminder, see opposite), which can be used to choose which new portal to shoot.
If a fizzler is touched (see section Energy items), the pre-existing portals are cancelled.
On the floor and ceiling, the portal is oriented according to the direction in which it is fired, but on wall or on an angled panel it is always in the same direction (see below)

Due to the only vertical orientation of portals on wall, a single light strip (see section Other items (2)) placed horizontally on a tile prevents the creation of a portal, whereas vertically on the left and right edges, or two on the same side, still allows it.
Trigger signs also prevent portal creation (see this item in section Automatic elements).

When both portals are created, they communicate and then serve to:

• pass oneself,
  
• propel themselves far, by diving into a portal to come out through the other with the momentum (see Untold Riches: An Analysis Of Portal's Level Design),
  
• observe from an inaccessible point of view, as with a video camera,
  
• move a mobile object (cube, turret) by making a portal below,
  or on a wall in which we throw it,
  
• pass the "energy" of an object (laser beam, light bridge, funnel).

Remarks:
-Also sounds (funnel generator in particular) pass through portals.
-The beams which go out of a portal can enter again the first one.
See opposite and: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=79511082

Always in test mode of course.

-It's possible to place two portals side by side on a single tile or on an angled panel, but it's harder on the floor or ceiling, and seems impossible on a panel inclined at 0° or 90° !
You can do some fun things with these close portals:
https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=189376619
https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=189376828 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=648200030 Above, how many cubes? ...
Only one in each picture, leaned on itself.

-It's possible to pass by a half-portal, on each side if it is centered well on the obstacle (see below)

-By placing the two potals side by side on a wall, one at the bottom the other at the top of the box, and by jumping on two cubes crossing them, it is possible to climb higher.
If the portals are on different squares, then you have to go through the portal to be at the top.
See the solution of this map: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=2007116260&tscn=1582842089 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=2009659616
-When an angled or flip panel containing a portal starts moving, it deletes it by making a noise and an animation.
And also, stairs, piston or rail platform rubbing on a tile with an open portal, "erases" this one. That can serve to prevent the player from going back where he came. A piston platform also removes a closed portal when it retracts.
Due to an invisible mobile block accompanying the components of the staircase and protruding around it (see section Moving items (2)), a portal placed at one end is erased when the staircase is activated (see opposite) and it is not possible to put a portal on the side that goes up when it is lowered.
In this video https://youtu.be/WJk3bXflRvY you can see that:

• two portals are needed so that there is deletion
  
• only one portal can be deleted
  
• the reticule always indicates two portals after deletion
  
• it is necessary to bend before entering under the stairs because the base is low.

-As long as we do not recreate a portal somewhere else, there remains a "ghost". The reticule always indicates two open portals, and if the item moves again where was the cleared portal, the animation repeats.
you can experiment by going up then down a piston platform several times to move it in front of a wall on which you have made a portal.
See this bug happened to me in a map containing BEEMOD items: https://youtu.be/vSkWPejAVnY There the platform to the left moves forward/back in reaction to my position. What is unusual here is the effect position on an invisible wall.

-A portal cannot destroy items nor the player; what is inside (or very close by) of a portal which closes is expelled.
If a portal is fired while there is already one of the same color, the old closes (and disappears) before recreating in the new place. If there was a portal of the other color, it will also close (clog) before opening again when the first one reforms.
To reveal these two points, do the following experiment: a grating is placed in front of a portalable wall, a portal is created above and another under the player (who cannot fall inside because of the grating). Every time we fire another portal on the grating, we jump in the air, because of the one who closes under our feet.

The effect described previously can be used to boost a jump, this is the "reportal glitch".
In this variation, we must fire a portal (not on a portalable wall) of the same color as the one we are nearby (and we just go through), to benefit from the repulsion of the portal which closes.
See: https://youtu.be/CoBY81_XK-E https://youtu.be/AWS34Seh9JA

-When shooting a portal, for reasons of speed, only some checks are made to find out if it is possible to create this portal. This results in many glitches presented here.
https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=1470868769
-If you fire a portal next to a vertical glass barrier, then fire a second portal on the first one (opened or not), or just between it and the barrier, the second portal tries to create itself next to it, but since there is no room at the targeted location, it tries to create itself further away anyway, even if this new position is normally inaccessible directly.
This leads to a glitch (called "Portal Bumping Bug") allowing you to create a portal on the other side of a glass panel.
It doesn't work vertically, with a horizontal glass panel.
See to the right and this example: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=76328141
-A cube can go through a grating placed in front of an exit portal (only in the direction entry towards exit); but the player can not pass it! (see opposite. We can also bring out the cube with the pistol from the blue portal).

-We can pass a cube through thin walls, doors, observation rooms or angled panels, by placing a portal close to them and in the same plan.
See the beginning of the section Automatic elements, and below.
https://youtu.be/Bg2n9_C7pK4

-The extremities of the light bridge generator do not touch the support, we can thus make a portal below and even manage to make it overflow on the central part (see opposite).
We can cross the item from behind (orange portal).



-A light bridge coming out of a portal and immediately meeting a window, crosses it (see below; the panel must be 30 or 45 °).
We can put an angled panel at the entrance and / or at the exit of portal as soon as the angle of the bridge makes the glass meet quickly.


-By going out of a portal, the player is slightly pushed; this effect allows to cross a thin obstacle (light bridge, grating, angled panel), placed in front of the portal. The phenomenon acts differently on the player and on the mobile objects according to the type of obstacle.
The player can go through the bridge but not through the grating, whereas for a cube it's the contrary!
Map exploiting this glitch: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=766067046
If another obstacle, thickest but with holes (the jacks of an oblique panel for example) is in front of the portal, as there is not enough room for the player, this one will be shifted to find more.
This leads to the phenomenon shown opposite.
A blue portal was placed at the edge of the white block when the angled panel (black tile) was lowered on the ground. If we enter obliquely towards the panel by a second portal, the pistons of the panel disturb the passage, the player is pushed then to the left and exits by the black square! We can even put a barrier stuck on the panel, we will cross it.
This technique allows to get into the space containing the observation rooms and in the base of pistons, panels and stairs! As we cannot place the panel just in front of the window, I did not find how to enter directly into the observation room, but only in the space surrounding this one.


Opposite, a device to enter above a room:
after creating both portals, we activate the button to pull down the angled panel, it is then necessary to crouch to enter the lower portal.




See below a view of a large room. Often we see nothing and we have to move so that contents of the room appears.

https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=404107073
See also the video Stairs and portals (section Portals (2)) and: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=169547230 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=169547011 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=169546807 A video showing another technique for getting through walls: https://youtu.be/TlbOR-osDtI
-When a portal is covered by an angled panel, the player can pass through the other portal, but be careful not to go too low, or the panel's mechanism will kill you. Risks can be reduced by jumping when entering, or by placing the exit portal at the top of the tile (see below).
You can also enter the "base" of certain objects. With the previous device, you should preferably make the exit portal at the bottom and crouch when entering.
Otherwise, it must be a glass panel, whose base is twice as deep as that of an opaque panel (see below, right).









Cubes also pass through, but if the panel is not of glass it is necessary to insist, or the cube has to arrive with speed (by falling from above for example).
Example of double use of the object traversal glitch: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=3512354357
Its the same thing if it is a piston or rail platform that covers the portal; we cross them. Similar also if the portal is made on a portalable panel covered by a piston or another panel.
See: Inside piston basement
By going out of the portal, a cube can get stuck in the mechanism or be ejected.
For the gel, only splashing go through.

A map consists of a room, with a maximum side of 25 tiles, with geometry limited to cubic bricks of a single size, decorated with some lightnings, and static or mobile objects.
After taking an object from the palette on the left of the editor, and placing it on the map, some can be oriented and/or shifted on the support tile, thanks to white handles that appear. Then a right click on the item shows a pull-down menu allowing you to change its properties (its behavior in the game).
In the editor, items appear larger than in testing, for better visibility and manipulation. This can cause defects as shown below; the cube is placed on the ground but the piston platform extends over it.





Some items contain a hidden "mechanism" in their base, occupying one or more wall blocks, this is why several of these items cannot be placed on the same support (see opposite, in test).
These items also occupy a certain amount of space in the air, which cannot be shared with others that would interfere with them. In case of a conflict, the error is reported and a space limit is displayed in red.
During the game, a blocked object makes a particular noise and emits some dust, it can then be expelled or destroyed.




Glitches:
-in the image on the right, the piston conflicts with the wall above because once deployed, there will be no more room for objects placed on the platform.
But if the wall is replaced by an angled panel, there is no error anymore, which allows objects to be trapped.


Glitches in test:
-in the animation below, the panel through the cube without being stopped then destroy it when it retracts. Whereas with a piston, the cube penetrates a little into the obstacle but stops the movement.



-the observation rooms generate projected shadows for walls and items (cubes, grating, gel...) but not for cube generators!
Sometimes the lighting calculation fails; on right, the shadow of the left cube disappears on the angled panel.



Most of these items participate in the action of the game and make all the interest and the originality.
We can classify these active items in two categories:
-the items that I call triggers, which react to the player's action, possibly through a cube (these are the buttons) or through a laser (relays and laser receivers).
-the receivers who react in events (= signals) emitted by triggers (they are all the moving items as the panels and platforms, or the cube and gel droppers, or those using "energy" as lasers and fizzlers).
A receiver is only activated if all the objects connected to it (triggers; a maximum of eight) are activated ( = logical AND).
A trigger can be connected with several receivers; a maximum of eight as well.
Knowing their behavior while playing is necessary to create the riddle (puzzle) and allow its resolution by the tester.

Each item in the palette is reviewed in the following sections, with an indication of the advantages and disadvantages of each, their lacks (regrets) and glitches found in the editor or during map testing.
After the common name, the official "poetic" name is written between quotation marks.
In parentheses comes the number of entities it uses. Indeed, each item placed in a map "consumes" a certain number of entities, and the editor authorizes a maximum of 1750. If you put a lot of items in your map, at launch (F9) you risk having the message "The puzzle has too many items and cannot be built. Please remove some items and try again".
See: 'Too many items' error
We can however push away this limit: A Way to Break the Entities Limit

Major objects of Portal, there are several types available in the palette, but you can also switch between them via the contextual popup menu.
They serve essentially to press buttons. The standard and companion cubes as well as the spheres have a part that turns yellow when they activate a button.
They can be placed "in the air" by raising them along a wall; they will fall when the player enters the map.
Regret: we cannot put a cube without distributor on a button or an angled panel (raised or not); it is necessary to put it above.
In the game, cubes can be used to interrupt a laser so that it no longer reaches a receiver (the reflection cube deflects it).
They can be stacked to form a staircase, allowing you to climb on it to scale a wall for example.
They can be covered with gel (see this item in the Gels section).
They are destroyed if they plunge into the goo or touch a fizzler, but also in certain situations, for example if one gets stuck against a wall for a long time by a moving item.

Glitch in test:
Cube pushing another through a glass panel, with solution: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=2813187698


"Weighted storage cube" (4)
It is used to activate the standard and cube buttons.


(4)
It works exactly like the standard cube, it just has a different design (heart) to make it more appealing.
Conventionally, only one is used in a map, and you often have to carry it all the way to the exit.


"Edgeless Safety Cube" (4)
Warning: placed on the floor, it wanders around on its own and tends to go where it shouldn't: towards portals, holes, fizzlers...
To block it, aside from using walls of course, you can for example use the base of cube buttons, the end of a laser field or fizzler (deactivated), or a funnel on the floor and inactive (or active and directed towards the sphere).
Placed on a standard button, it activates it, but it can sometimes start moving and manage to escape!


(4)
It's a hybrid of a turret and a cube, but the turret part can't be destroyed by a laser.
It can look slightly different in each distribution.
See these examples (click to enlarge):

It seems to wander aimlessly, but if you pick one up and place it in a certain direction, it will move in that direction. You can then use it to activate a device, or pass through a portal.
It can go down a staircase but not go up it, and can't step on a button on its own.
When placed on its back or side, it can't move any more.
Regret: placed in a map, its orientation is always the same, it cannot be turned unlike reflection cubes and turrets.
Glitches in test:
-it does not bounce on the blue gel and does not accelerate on the orange gel, nor even if it is coated with it, contrary to the other cubes. On the other hand, covered with blue it pushes away well the other cubes.
-when you place a Franken cube on a button, it goes into idle mode; but it still stays in this mode (it no longer walk) when you remove it.
-when a franken cube strikes a cube dropper by below, it rises as this the gravity was inverted. See: https://youtu.be/mUHQM9kfaDw

It is dealt with lasers (Energy items section).



(33)
This cube generator is optional, and it delivers only a type of cube.
With a selected cube distributor, the Delete key does not delete the cube, but Delete on the cube deletes both.
The destruction of a cube can cause the automatic dispensing of a new one (option in the contextual menu).
If a cube is requested via an item connected to the dispenser, the previously generated cube is destroyed.
Moreover, a map may require the destruction of a cube for an other to be generated under the distributor, thus creating a sort of cube transfer (called "respawn").
The reflection cube, still in its distributor, works (it deflects a laser)! But its orientation cannot be changed. See:
https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=75349381 A laser placed under a generator sends its beam inside by the small hole in the center of the diaphragm (see opposite).

Glitch:
-it is possible to place the cube at various heights under its generator without perceived utility, but can produce the visual problem shown opposite. Without the dropper, a message indicates a wrong position.

Glitches in test:
-a cube in its dispenser and crossed by a laser placed underneath or horizontally (centered or at the bottom of the support square) is blocked. By cutting the beam, it can fall again.
-the portalable base of a cube generator is always black (see opposite).
-if the cube is blocked in the dispenser from the start by a light bridge directed upwards, the distributor will no longer work at all, even if the bridge is cut.
The output can be blocked by other items placed underneath: an angled panel, a funnel, a laser, a glass panel...
-if you grab a cube before it's completely out of its distributor, and put it back in, the diaphragm closes on it, and it becomes trapped with the next cube. Then if you request a cube, the one that was reintroduced destroys itself but has time to block the descent of the next one, meaning you can no longer obtain any more cube (see opposite). It can also happen that two cubes come out together! See this video: https://youtu.be/pPCKvEdjAGE A trick allows to force the release of a blocked cube; see: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=393881288

(switch) (6)
Its unique feature is that it triggers two types of events: either permanent or lasting 3 to 30 seconds, after which it returns to its initial state and can therefore be used again.
You can also jump on this object to climb a wall, especially when the button is horizontal.
Regret: no less than 3 seconds to the countdown, it's a bit long sometime.

Three other types of buttons are available in the palette, but you can switch between them using the context menu.
These buttons can be placed on walls or ceilings; to activate them you must press them using a cube (one-time action) or use a funnel beam that holds a cube against the button (effect as long as the beam is active).
Glitch in test: Sometimes, when titillating the button with a cube, the button remains triggered even though the cube is no longer placed on top of it!


"1500 Megawatt Aperture Science Heavy Duty Super-Colliding Super Button" (3)
Standard or ordinary button, it can be activated by placing any cube on it or stepping on it.


(3)
It can only be activated by cubes (with edges ;o), and not even by the player.


"Edgeless Safety Cube Receptacle" (3)
On the contrary of the cube button, only the sphere can activate it.

(13)
Panel that can take a predetermined angle upon receiving a signal.
Regret: you can only choose one tilt angle, the other being set to 0 degrees (also applies to the glass panel).
Glitch: sometimes a portalable panel is displayed in black in the editor, but is indeed white during gameplay.
Glitch in test: like the glass panel, it can trap you while moving, but less systematically.


(12)
Its only difference from a regular angled panel, aside from its appearance (it's easy to spot, unlike the full panel), is that it can't be portalable.
It's also noticeable that it allows for indicator lights to pass through (see this term in Automatic elements section), and compartment for arms is deeper.
Furthermore, this panel is slightly narrower and a portal can be shot through the edge (see below, click the image to enlarge).
Strangely also, it costs one item less than the other panels!
Regret: you can see (a little) through it but the laser can't go through it.
Glitches in test:
-it's possible to extract a cube from behind through portals, like on the left picture below, if you place the cube on an orange portal. If the cube falls onto this portal with enough speed, it will pass through the panel without needing to be pulled.
-a cube that hits it has high chance of being destroyed!
-if it's activated while you're in its path, it traps you! (see below, click the image to enlarge).



A panel (glass or not) placed on the wall and tilted to 90° towards the floor (on the right in the image opposite), can serve as staircase, whereas if it is on the floor and facing the wall, you slide on the pistons.








(8)
It allows, upon action of a trigger, to change the portalability of a tile.
The rotation axis of a flip panel on a wall is always vertical. To change the axis orientation of a floor panel (rotate it 90°), it is necessary to move it to a wall before returning to the starting tile, as shown opposite.
You can place a gel spot on it and thus show or hide this spot.




(44)
ou choose the extension length (maximum 4 tiles) and the initial position of the platform (retracted or extended).
You can rotate it on its axis, but this only changes the platform shape.
If a platform pulaced on the floor is not connected to a trigger, it will be activated when the player lands on it. It will retract if he leaves it, even before the end of its way, or if he stands at the very edge.
If it is connected, it will return to the other extreme position when a signal is received.
A piston placed on wall or ceiling does not react to player contact; it can still be used to close a passage or push cubes or the player.
The platform and the piston stop the laser, the light bridge and the funnel (if it is centered).A piston platform can be placed facing a panel (angled, glass, grating or other platform) and come to touch it, but not facing a wall (see Glitches in Items section).
Glitches in test:
-a piston not connected reacts to the player's presence even if the platform is covered by a glass panel or a light bridge. A downward platform will then vibrate mid-stride as long as the player is above it.
-if a piston is connected to a emitter, and is copied, the connection is removed from the copy, this is normal;
however the new piston will no longer be triggered when the player stands on it, as if it had kept memory of the original's connection.
-if the platform extension is hindered, the piston still deploys (see below and opposite).



https://youtu.be/S-WoKfo_HRs

(13 + (1 or 2 ?)*length)
Moves back and forth along a rail when activated. The orientation and initial position of the platform on the rail can be changed in the editor, but not the starting direction.
Often used to stop a laser beam, thus generating a signal cyclically (see Systems section).
An option allows to deactivate coming and going; in this case the starting position can be only one of the rail ends, and the activation of the item by a trigger sends the platform to the other end.

Piston and rail platforms as well as stairs that move can give the player momentum to jump higher.

(13)
It deploys or retracts upon receiving a signal.
Regret: this item is rather bulky, and "entities" consumer just to move the player up one block. You can do almost the same thing (albeit less attractively) with a panel tilted to 45°.

Glitches in test:

- Opposite there is a view of the Stairs instance (prefabricated object used in the construction of PeTI maps).
When the staircase is activated, the red block will move up or down at the same time as the steps (let's call it "mobile block").

This explains why the cubes placed on the deployed staircase do not exactly touch the steps (see opposite).
We can also see that it protrudes a lot in the lower part and a little on the upper side (I think to allow the player and cubes to slide over it smoothly and to create a solid block around the legs).
Because of this it can be blocked during deployment or retraction if another object is in the way.
See also the interaction with portals in the section Portals (2).
You can also stand on a ledge and move with it if the staircase is activated by a device. This is what is exploited in the following map: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=1368004183
The large ledge is wide enough to pass through a barrier (see below).
- Another consequence, if you place a barrier (glass or grid) on the side of the staircase that leads up, it will obstruct the mobile block and after deployment of the steps, you can pass through the legs (see below).














- Conversely, if the staircase is deployed by default in the editor, when you retract it, the mobile block stays in place and you therefore have an invisible staircase (used at the beginning of the map MicroP2);
and see opposite: after placing the cube on the button, you can still climb the stairs.

- A barrier at the same level as the base of the staircase but on the low side, vertical or flat, stops the mobile block before it reaches the top completely; see opposite: the cubes touch the steps but the legs are not crossed by the light bridge.


- The "Ski lift" glitch.
To create this glitch you need the same setup as before, but the staircase must be deployed initially; if a cube (not the sphere) is dropped above the stairs, it slides down then turns back and slowly climbs back up. It continues even after the stairs, until it encounters an obstacle and falls.
The conditions for this to work are not very clear. Sometimes any modification of the map cancels the glitch, and sometimes it stops working without having made any changes and it comes back when relaunching the map. To restore it, you often just need to delete the staircase and add another one.
In this video: https://youtu.be/c28cbXmZpbw you see that:

• The cubes float above the steps.
  
• If the player approaches the cubes or if another cube is placed lower on the ramp, the other rising cubes slow down, seem to "hesitate", and may abandon their ascent if they are beyond the staircase.
  
• We can put any cube, anywhere on the stairs, it rises (except the first one who comes down first).
  
• Cubes refuse to go into a portal.

To test yourself: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=645398084
Analyse
- Without the barrier
The falling cube hits the mobile block tilted above the steps, then slides over it. The higher the starting speed, the further the cube will go; it can stop on the stairs, or on the floor below.
A degree of randomness has been added to make it more realistic and less predictable; the cube rolls on itself, and the trajectory can deviate to the side of the stairs.
- With a barrier
If the cube is stopped by a thin barrier (or slowed down enough to not exceed the barrier when it's horizontal) it's as if it bounces and the slide continues in the other direction.

The required configuration is the same as for the previous glitch, but the behavior is different; the mobile block is fully deployed when the barrier should have blocked it.
I tried with two identical devices (staircase, cube distributor and a glass panel), and there was always only one staircase glitching at a time; and each time the map was launched, it wasn't always the same one.
If you lower the staircase and then raise it using a button, the glitch disappears. The cube touches the stairs and slides very little: the mobile block got stuck underneath.
- Assumption
We notice in the Stairs instance that the staircase is retracted while the mobile block is in the upper position. When the map is initialized, the staircase should be positioned as configured. So I assume that something is wrong with the positioning and the conflict between the mobile block and the barrier for the first encountered staircase.
- Mystery
When a cube is placed behind the others (or the player climbs the stairs), they are affected, and those further away fall. If a cube is placed in front of those that are starting to climb, it is affected like the others.
And why doesn't this glitch always work? Perhaps it is the order of the elements in the source and the timing at initialization, or the randomness parameter (realism) that's at play ...


(9)
Allows to propel the player, as well as any objects that come into contact with it, towards a target placed on a tile. The plate cannot be placed on the ceiling, but the target can be placed almost anywhere, even if it is not aligned with the plate. It can also be placed in an inaccessible location; the projectile will then be stopped before reaching it.
You can perform a completely vertical jump by placing the target on the ceiling just above it (if you place the target on the plate itself, it will be sent back to the ceiling).
The jump height is adjustable; but be careful not to hit the player against a wall!
Regrets:
-The target cannot be placed on a barrier (but the trajectory can go there).
-It cannot be connected to a trigger to control its action.
Glitches in test:
-A target placed on an angled or flip panel will be invisible in test mode.
-Once in the air, you can deviate from your trajectory by using the left, right and back keys to avoid landing exactly on the target. This feature is so effective that you can even go backwards from the plate!
-the Faith plate is intangible to gels and portal shots. By spraying conversion gel on it, it passes through the plate and covers the inside of the box containing it; you can then create a portal and pass through it (see below).
https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=1492967902 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=1502636917

"Thermal Discouragement Beam" (6)
Warning: if you touch it, it hurts you and pushes you away, but if you persist, it will eventually kill you...
It can be oriented using the reflection cube, and it can be used to destroy turrets.

(4)
It is triggered by receiving a laser beam.
Be careful, as it can have multiple positions on its mount, it must be aligned with the laser that is intended to hit it; otherwise it will be necessary to use portals or a reflexion cube to match the height.
In this case, there is a certain tolerance on beam arrival angle, it doesn't need to be perfectly perpendicular and in the center.
Glitch in test: it can be activated if the laser simply grazes it; see opposite and: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=918278815
(3)
It lights up and rotates when a laser beam passes through it.
It can receive beams from all directions, in the same plane as its base, or vertically; but there is very little tolerance on the vertical angle of the beam.
Glitches in test:
-It may happen that a relay hit by a laser rotates but does not light (see opposite).
-A relay placed on a wall cannot be activated (whether the laser is placed on the floor, ceiling or on a perpendicular wall), except indirectly via a portal. Example: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=79511082

(or Weighted Pivot Cube) "Discouragement Redirection Cube" (4)
In addition to the functions of a regular cube (see Cubes and Buttons sections), it serves to deflect a laser beam.
Multiple lasers can hit it simultaneously, but only one beam emerges. In the game, when you pick up this cube, it orients itself with the small exit lens in front. You can direct the beam up or down with the help of another element on the map to tilt the cube. Afterwards, you must not lift it, otherwise it will reorient itself; to move it you must therefore push it or hold it against an obstacle.
Stacking a reflection cube on top of other cubes or items, allows you to capture a laser beam from above.
Glitches in test:

-In a stack of cubes, if the top cube is a reflection cube and has a laser beam through it, you can remove a cube from below without dropping it! See opposite.
-A cube in its dispenser and has a laser beam through it (see Cube Generator in the Objects - Cubes section) is blocked. By cutting the beam, it can fall again.
-If there are more than 28 lasers (active or not) in a map, the reflection cube cuts the beam instead of deflecting it.
-If you use a lot of reflection cubes, the laser that passes through them glitches at the end. See:
https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=72078309
-in a funnel, you can get close enough to look inside (this works with other cubes, but less spectacular). See opposite:

And below, probably the same glitch. It may have been fixed because I can no longer reproduce it.



https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=231079294
-if a lot of reflection cubes are used, the laser which crosses them bug at the end. See: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=72078309

"Discouragement field" (14 + ?*length)
This barrier lets everything through (it doesn't even destroy turrets) but kills you if you touch it!


"Material Emancipation Grid or Grill" (5 + 9*length)
This barrier destroys objects that touch it, but not you. It also prevents portal firing, and if you touch it, pre-existing portals are cancelled.
Warning:
-It is possible to walk on the ends of a barrier (fizzler and laser field) placed horizontally, without activate them.
-It is possible to pass a cube over a fizzler (if there is nothing above it) by holding it "at arm's length".
-If the fizzler is positioned in a certain way relative to the walls, a portalable gap can be left on each side (see below).
-Similarly, a fizzler parallel to a wall allows a portal behind it, while a perpendicular one prohibits it because it touches the wall (see below on right).

-a portal can be shot on the edge of an angled panel perpendicular to a barrier; the portal centers then on it, which can allow to pass on the other side of the barrier (see below).


Hazard barriers remarks:
-These "hazard" barriers (laser field or fizzler) can be extended as long as their generators are in contact with a bare wall. Any other object except the grating, creates a conflict.
Moving items (piston, stairs, platforms) cannot be placed if they cross the field when extended.

Warning:
-It is possible to walk on the ends of a hazard barrier placed horizontally, without activate it.
-These barriers have an emitter and a receiving part (generators). The only difference is that the indicator light line (see section Automatic elements) reaches the receiver; therefore the placement can be chosen for better readability. Furthermore, these items can be placed on a tile in two mid-positions, almost identical (flipped 180°) and only the design of the ends and the position of the indicator light change slightly (see below on right).
-You can pass without touching them, on half a square (see below on right).

"Excursion Funnel" (8)
This item is unique because it accepts connection to two triggers; one to switch the beam on/off, the other one to change its "polarity" (its direction of travel, indicated by the beam's color: blue for pushing, orange for pulling).
It can be used to transport cubes, and if a button is placed at the end of the pushing beam (blue), they will press it... but the player, cannot press the button, even if it is on the floor! There was a bigger difference in behavior between cubes and player, but this has been corrected. See: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=90192571
Gels and turrets can also be carried in. A light bridge can stop objects and the player.
Glitches in test:
-with an inverted beam (orange) the "sparks" also change direction and pass through the support (see opposite).
-when reaching the top of a vertical funnel (or the end of a horizontal one), wait a bit without moving, crouch and wait again, press the jump key while holding down the crouch key; the player can then float along the ceiling by using the movement keys. See: https://youtu.be/in_Qs0zCg18 Video with other glitches too: https://youtu.be/T2qcoQC9cTc
An other property/glitch used in a map: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=848757551


"Hard Light Bridge" (4)
This item offers a wealth of possibilities, as it can be placed it on walls of any orientation, positioned in several ways on its tile, and can be brought out through a portal on an angled panel. If the panel is tilted by more than 45°, however it cannot be raised by walking on it.
It doesn't stop portal shooting, laser beams or funnels, but it does stop turret shooting and moving objects. Depending on its orientation, it can serve for the player as a bridge, a ramp, a shield against turrets or other hazards.
If a light bridge encounters mobile items (cubes or player, but not turrets!) it pushes them, and if it's horizontal, it lifts them onto itself. In the latter case, successively created upward portals make lift these objects with it.
Glitches in test:
-objects, including the player, can thus go through a grating! (see below)


-the light bridge generator is intangible to the cubes, but not to the player:

In the editor, place a fountain (the distributor) and the target (a spot), both must be aligned (a mark indicates the possible squares for the spot depending on the distributor's current position).
With a fountain selected, the Delete key deletes it and leaves a spot, but Delete on a selected spot deletes both.
In testing, the gels pass through grating and don't adhere to glass (glass panel, platforms, angled glass panel, observation rooms); they disappear!
You can send gel onto a light bridge, even from below (using a portal or a funnel); both sides will be covered, and blue and orange gels will work.
You can color the entry and exit doors blue or orange with a spot; both faces will be colored.
Gels are tricky to use (especially conversion one) because it is difficult to predict what the player is going to make with. It is necessary to be very attentive to portalable squares and to funnels which can serve to send the gel almost everywhere on walls and thus to greatly expand the possibilities of travel of the player.
Remarks:
-gels cannot be mixed; the last gel poured replaces any previous one
-you can pour as much gel as you want, the thickness of the layer will not increase.
-a surface coated with bouncing or accelerating gel keeps its portalability.
-a gel bomb explodes upon encountering a laser beam.
Glitches:
-you can't put a gel spot on an inclined angled panel. In test mode, the gel will paint the underside of the panel.
-if you remove the wall supporting a spot from the side (selection and - key), the spot remains suspended (see opposite). In test mode, it will join the opposite wall. This trick allows you to put an initial spot on a light bridge or to paint objects in the path.
Glitches in test:
-gels spread on light bridges disappear if the bridge is removed. And they are not saved with F6 key!
-gel placed on a deployed staircase does not work.
-if a gel spot is placed on a laser transmitter, receiver or relay centered on the square, the effect (bouncing or accelerating) and color only apply to the items and not to the support. On light sources, the spot is not visible, but the effect is still there (See opposite).
-in "bomb" flow the gel cannot fall from a distributor placed on the wall if the drop angle is too vertical.
-a gel bomb falling on a faith plate is sent back, but it can also crash: it depends on the height of fall! See this demo map: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=117604573
-in the editor, you can't put a gel spot on a glass panel; it goes through it and end up on the wall behind it. In test mode, poured gel disappears when it touches the glass, unless it's against a wall, in which case the gel sticks to it, behind the glass!
In this video : https://youtu.be/Z-MZyOr4lqw we can see that:

• the orange gel doesn't work but still makes noise
  
• the cleansing gel works
  
• the blue gel doesn't work for cubes, but for the player it keeps its properties except for one detail: you have to jump from higher than the floor for it to work (the height of the base of a button is enough)
  
• the conversion gel works and you can spend a cube through the glass!

If the floor is replaced with an angled panel, the gels will never work.

-if a funnel coming out of an angled panel (on the wall or floor) passes over a paint dropper, then the gel will no longer come out of the dispenser but will come from inside the funnel.


(8)
The player bounces if he jumps on a spot of this gel; he can avoid this by crouching.
Coated objects bounce indefinitely (the Franken cube does not), and repel free objects that are touched with them (the Franken cube does as well).

(8)
It makes surfaces and objects slippery (except the Franken cube). Walking on it increases the player's speed, unless he moves forward carefully or if he crouch. This gel only works on the floor, not on walls or ceilings. Objects covered in propulsion gel also have reduced friction, making them slide more easily.

(9)
It makes portalable surfaces that aren't. A spot on a square that's already portalable is visible (it's greyer) but has no additional effect.
Applied to a cube it has the same effect as cleansing gel.
This gel is difficult to use in a map because by making all walls portalable (provided you can reach them) it makes actions too easy...

(8)
It's used to remove other gels, and a surface being watered cannot receive any other gels during this time.
A spot of this gel seems to have no effect.
It's really only useful for removing the blue gel that has been coated on a cube, to restore its normal behavior.

(15)
You can't put it on the floor, but you can make a horizontal throw by putting it on a wall.
Glitch: When you copy a distributor with the C key and move it, the spot does not follow. In test it will be vertical to the paint dropper.
Glitch in editor and in test: The distributor is intangible for portals, laser, funnels and light bridges! (see opposite in test mode; click to enlarge).

(1/2 *taille)
The palette only offers the glass panel (armored window!) but you can switch from one type to another via the context menu.Glass and grating panels cannot be overlapped. Adjacent barriers of the same type visually merge, and the effect is the same as with a single barrier (also in terms of units consumed.
In the image opposite, you only see one L-shaped panel, but two items had to be placed on top of each other to create this shape.
You can walk on the edge of a vertical panel.
Only lasers can pass through glass, while light bridges, funnel streams and the shootings of turrets and portal only pass through grating panels. Some glitches allow you to pass through a grating (see Portals (3) section).
It is possible to manipulate an object (cube, turret, pedestal button) through the grating if it is not too far away.
Warning: two right-angled glass panels on opposite squares are not quite joined and a portal can be fired between them; as well as between a glass and an offset wall (see opposite).
Similarly a turret can through the gap but without causing damage.
Regrets:
- it is not possible to use glass panels to contain the goo!
- it is not possible to attach a panel on another panel.
- the grating pattern is too tight, it is difficult to look through, especially if there are several overlapping ones.
Glitch: it can happen, rarely, when rotating a barrier in a narrow place, that part of it turns only of 45° instead of 90. See: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=85099727

(3)
You can choose the direction the turret "looks" and can shoot at you.
Regret: you don't choose the width of the viewing angle.
A cube can be used to knock down a turret by dropping it on it, or act as a shield against gunfire.
A turret can be burned with a laser beam, but strangely, it isn't affected by a laser field.
Turrets can fire through the staircase mechanism. They also fire into the gap that can be left between glass panels, but bullets don't go through.
They don't fire through portals or if they are in a funnel.


Bullets leave marks on walls and pedestal buttons (see image opposite; click to enlarge).


Remark: turrets are used in most of the workshop maps as deadly traps that surprise the player and force him to restart the game. In my opinion, it is better to use them more intelligently, allowing time to observe the situation and to bypass or eliminate them. There are also multiple ways to get rid of turrets, by making them fall or destroying them from a distance (laser, portal...). See: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=73887612 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=1345758051
Glitches in test:
- turrets can be temporarily disabled after passing through a funnel. See this demo: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=132141209
- shots from a turret attract a cube: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=1718340573 and the solution: https://youtu.be/kqtRVRpxb5A

(1)
It destroys anything that falls into, including the player.
The stickman symbol can be placed on any square in the pool.
The level doesn't reach the very top, and the emerging part is automatically non-portalable. However a light bridge or an angled panel can be placed there to create a small platform. Moving platforms can enter the goo.
Certain items can be placed at the bottom of the pool, and only at a depth of one tile. Regarding immersed cubes, they will be destroyed as soon as the game begins.
The goo prevents indicator lights and connection signs (section Automatic elements) from connecting to items placed at the bottom (pistons, angled panels).


Regret: The glass panel cannot serve as wall to contain the goo.
Remarks: You can put multiple goo items in the same basin but I don't see the interest. Nor make a basin deeper than one square (except to connect it to another basin and thus save one entity).
In reality, you can submerge a cube into the goo without it being destroyed, or walk inside on an angled panel (a splashing sound is heard) ; see opposite. Destruction only occurs when the object reaches the bottom.
Glitch in test: a texture problem may appear if several basins are placed at different heights. See this guide: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=126121406

(2)
This item is only used to decorate and light the scene.
Warning: it is possible to walk on the raised ledges.
Glitch: a trick allows you to place an observation room on the floor; see: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=397387268

(3)
While its primary function is to (slightly) illuminate the scene, it can also be used to prevent or reduce the portalability of a white surface. Up to four bars can be placed on a single square.
It also influences the layout of light indicators (see Automatic elements section).
It can also be use it to draw attention to something, mark a path to follow...

By automatic, I mean elements not found in the items palette because they are managed by the program.
These include the doors and the large observation room, which are automatically present in every new map, and cannot be deleted nor duplicated...
Except that a bug allows them to be duplicated anyway with the C or Ctrl+D keys; but these copies cannot be deleted (except by cancelling the operation with Ctrl+Z).
An other Glitch: when a portal is located on a nearby wall, cube can pass through closed doors and observation rooms (see below; click to enlarge). The cube will be destroyed by the fizzler behind the exit door. A cube coated in blue gel will bounce into the observation room.



(254 ?)
They are unique (in principle) and mandatory, since the goal of a test room is to reach the exit from the entrance.
The entry door closes definitively as soon as you pass through it, then the large observation room lights and the cubes fall from the distributors, as well as cubes placed "in the air".
The exit door is a receiver and therefore reacts to connected trigger items.
Glitches in test:
-a light bridge directed towards the entry door crosses it before it even opens, blocking the player if he is in contact with it.
-copied exit doors:
They are all in the same state (open or closed) and react together, regardless of the connections and the triggers.
In the published maps, some function normally and lead to an elevator, while others result in a visual "bug":


It serves to brightly illuminate the map, and casts shadows.
It's mandatory and unique in a map, but it can be hiddden in an inaccessible, enclosed area if necessary.
As with the little observation room, you can walk on the horizontal ledges.
Regret: You can't change its size; and it blocks a lot of space behind it.

(1 for every segment and bend)
This is a dotted line connecting a trigger and a receiver. It starts out blue, and during testing, it turnd yellow-orange when the trigger has activated the receiver.
The line is drawn automatically; if the program doesn't find a possible path, it replaces this line with a connection symbol at each end.It doesn't pass through the light strip item, which can therefore be used to constrain the path.
Because it always connects to the same side of the items, it can take a strange path (see opposite).
When there are many of them, and in a confined space, the interpretation can be confusing. Moreover this line consumes entities!
This is why the "Connection visibility" option (which was not in the original version of the editor) accessible from the context menu of active items, allows you to choose whether to use connection signs instead, or nothing at all.
Glitch: a trick allows you to delete the starting item while leaving the line; see: http://gtm.steamproxy.vip/sharedfiles/filedetails/?id=395550329

They replace the indicator lights when it cannot be drawn or when the designer has chosen this option. The drawing is identical on each pair of connected items.
There are 10 different signs in total; if more links are made, the same sign will be reused.
In some cases (space is too small), even the sign of connection does not have enough room to be drawn. See opposite, in design mode.
Remark: if a system (see the following section) is inserted between a transmitter and a receiver, the connection is no longer clear to the player.

See this guide: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=292356592
If a receiver item is connected to more than one trigger item, a blue cross is drawn next to each connection. It turns into an orange check mark when the connection is established.
These symbols also indicate how many steps are required to activate the device, since all the crosses must be converted to checkmarks (a logical AND) for the receiver to respond.
For a pedestal button with countdown timer, the sign is a wheel which will display the countdown after activation.
Remark: It is not possible to create a portal on these marks.

Here are some examples of assemblies of active items forming useful systems or devices.

An airlock is here a passage that can only be crossed in one direction.
A pedestal button with "infinity" counter is connected to two "doors" (Laser fields in the example opposite, but anything else can be used), one of which is open and the other closed by default.
If the player decides to go through the airlock, he must press the button, and the entry door closes while the next one opens.

This system allows you to convert a one-time event into a permanent one.
Pressing a pedestal button with timer, or hitting a cube against a button, trigger an event for a limited time.
The system presented here makes this event permanent, even after the trigger is turned off.
In the image opposite, pressing the left button turns on a laser for three seconds and opens the glass panel via the relay. Yet the door remains open indefinitely!
This is because the relay is also connected to a laser (on the right), that activates when the relay receives the first beam; and since the second laser points at this same relay, a loop is formed that "traps" the event.
And how to cancel this effect?
It's not that simple, because if you turn off the right laser via a system with a button, the relay no longer receives the beam, so its state changes. It then sends a signal to the laser, which turns back on and passes through the relay which changes... and so on.
So you don't have to cut off the laser source, but obstruct the beam to stop the power supply of the receiver (the relay), which will turn off the laser that's still on, and thus break the event loop.
For this, all moving or tilting panels are used. When activated, it cuts off the laser and disarms the system. This is the function of the button on the right in the image.
Exemple where four such systems are used to activate in a chained loop: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=78776811 Example of using this cyclic system: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=182952465

-Automatic mechanism: a hidden (or not) system, where the player does not directly intervene, using moving items (often based on rail platform cutting laser beams) to generate "effects" in a map.

-Delay: a system that insert a delay between a trigger and activation of the receiver. These systems generally use a button hit by a falling cube or brought by a funnel, actions that take time.

-Countdown: simulates the triggering of a pedestal button with timer (limited duration). For example to spray gel "a certain time" or to activate a "persistence" system.

-Random generator: a system that acts unpredictably on different receivers. For example the position of a hidden moving cube that will be taken into account when the player triggers the system.

-and so on...

The combination of trigger items (buttons) and receiver items can result in "logical" or "boolean" operations, i.e. AND, OR, XOR (exclusive OR) and NOT relationships.
For example, two buttons connected to the same panel form a logical AND because button 1 and the button 2 must be pressed at the same time for the panel to activate.
Now if we want to activate the panel when either one or the other button is pressed, we must build a logical OR.

Each of the two (or more) buttons is connected to a laser instead of directly to the panel. Each laser points to the same relay, which is itself connected to the final panel. Other objects can be used to create an OR but this method is the most economical, and allows up to four links (even five with a lazer above the relay).
If you activate one of the buttons, the corresponding laser will hit the relay, which will then activate the panel. Pressing multiple buttons has the same effect as pressing a single one: it's an inclusive OR. To create an exclusive OR, XOR (pressing only one of the buttons activates the panel) it is more complicated...

To make pressing a button disables a system instead of activating it, simply reverse the initial state of the receiver item (right click, disabled by default).
However if this receiver is already connected to other systems, it is not possible to modify it.
Therefore it is necessary to use an intermediary which will be enabled by default.
The button is connected with a laser activated by default and pointing at a receiver that is itself connected to the final item. Thus pressing the button inverts the state of the laser, which inverts the state of the target.

Links about systems in general
Examples of maps with many mechanisms:
https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=95354929 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=77595382 A collection bringing together many maps with systems: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=76666950 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=109237920 Other maps here:
workshop of cyron43
workshop of N_Sunderland
System test video: https://youtu.be/yJGwzykEoCE
Logical systems Portal 2 Puzzle Maker/Logic Gates
https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=76833448

In the previous sections, glitches were reported regarding portals or various objects. Others concerning the interaction between various elements are presented here.

Warning: If you exploit glitches and bugs in your maps, they may be fixed by a Valve update via Steam without you being notified... Maps have already become unsolvable because of this!
Example: the behavior of cubes in funnels was different from that of the player.
A partial fix was made first: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=90192571
See also: Portal Series

Glitches or features?

In test mode:
-Lasers don't hurt the player when he is moving quickly on the orange gel.
-During a jump from a faith plate or traveling in a funnel, lasers don't hurt, except for vertical ones.
-In the editor, cubes can be placed above vertical angled panels. In test mode they stay in place on panels inclined at 60 or 90° (even the spheres, which usually move around on their own), and fall from the others. With a little skill, you can reposition the spheres on the other panels (the two on right, below) without them moving (easy with cubes).
If panels, connected to a button, are folded down, the cubes are destroyed.
-Cubes placed on a glass panel or a grating do not touch it! For simplicity, the item is considered flat and having the frame thickness. (see below)


-When a horizontal flip panel is activated, a cube placed on it is either ejected or stuck, depending on which part it was placed on.
-A cube placed near the hinge of a perpendicular angled panel is "knocked down" when the panel tilts, as if it were placed on it! (See below).
-A sphere, a franken cube or a turret are destroyed if they come into contact with a glass panel or grating behind which there is a perpendicular fizzler (see below). A portal shot on the contact line causes the fizzler to react as if its energy were passing through the barrier. However, it is possible to place a Franken cube or a turret on their legs on the horizontal panel without damage!


-If a pedestal button is placed in a certain position relative to a receiver item connected to it, the round timer sign does not appear, and when the button is clicked, the countdown sound does not occur (see below).
-If a light bridge is placed on the edge of a funnel, a sphere placed on it will rise (or come down) while a cube will remain at the height where it was placed (see below).


-There is an invisible edge at the base of platform, flip or angled panels items. See below (click to enlarge).
You can jump onto the base of the item (from the staircase for example) and move horizontally, and even pass over the nearby items. But once you reach the angled glass panel, as it is slightly recessed relative to the wall, you can't leave it any more.
If you land on an object (from a faith plate for example) and remain pressed against the wall, you will be stopped when you reach the base.
If the angled panels are at 60°, you slide and the edge won't stop you (see below).


-If cubes are placed on an angled panel were there is an open portal, when the panel is retracted, the portal disappears (normal) but the cubes remain in the air! The reticle always shows two portals. Items fall if a second portal is created.


-The flip panel can be placed in the goo (at the bottom or at the edge) and then displays an error indicator (invalid position; see opposite). However it doesn't turn red like other items would in this case.
The map can then be run and the panel activated. When tilting, you'll notice that the hole in the base is filled by a wall texture.






-Sound glitch: in the image on the right, when you pass through the portal created on the horizontal angled panel placed above the goo, a lapping is heard as if you were walking in water.








Collections, maps and videos showing glitches: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=358056841 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=1404746664 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=238042497 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=215559366 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=114035661 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=81098354 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=75325781 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=903090644 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=153627807 (Edge Glitch Testbed seems not working anymore).

A map should be flawless if possible, and a good understanding of the techniques and problems outlined in this guide is helpful for this.
It should also be fun to play and therefore not cause the player to become stuck, for example.
https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=384089789
A discution: How to make great maps
and these guides: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=115008833 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=155812535 https://gtm.steamproxy.vip/sharedfiles/filedetails?id=264300097

Once your work is finished, you need to share it with the whole world, and publish it on the workshop. To do this, the editor menu offers the "Publish" option.

The view used to represent the map in the workshop is the same scaled-down view as the one in the editor when you publish. You must therefore orient and zoom this view correctly beforehand to ensure it looks attractive and readable. For precise zooming, use the bar that appears when you hover the mouse over the right edge of the screen.
Warning: If you make changes afterward, republish, but don't delete before, or you will lose the entire history (comments, votes and links to this map).
If you've edited the description at the workshop level, you'll need to recopy the text before republishing. And the text you can enter in the editor is more limited in size and doesn't accept accents, unlike the one in the workshop!
Publishing your map (possibly in private mode) before it's completely finished has two advantages:
-use the F6 and F7 keys to backup and restore during the test.
-be able to create and play a "demo" recording (see farther).
Glitches: sometimes a map you have subscribed disappears from your list; in fact, no one can subscribe to it anymore. The author then has to republish it.
It can also happen that republishing creates a new entry in the workshop instead of updating the old one; see this guide: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=142353952

To enhance your workshop, you can add screenshots or videos taken during the game, without (too much) revealing the solution, or any other image.

The key that takes screenshots can be configured in keyboard options. The images can be sent directly to the workshop. However, it's better to retrieve them for further editing. To do this, upon exiting Portal, a window appears offering, among other things, the option to open the folder where they are stored.

The Console commands is a window allowing to type system commands recognized by the game engine during a play.
It is displayed by pressing a hotkey (configurable in the advanced keyboard options). The Escape key allows you to return to the game.
A very useful command for testing a map in development because it allows you to "fly" anywhere: sv_cheats 1, noclip [Enter]
https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=263127894
The "bind" command allows you to assign a command to a key for easier activation.
Documentation for bind.

Demos recording
A demo is a file that contains a recording of a play sequence in the form of commands, instead of images.
This demo can be played in-game to review the sequence, much like a video but with the current configuration of the game in which it is played.
Furthermore, a demo file is much smaller than a video, but you must subscribe to the map (published on the workshop) to be able to play the demo.
Certainly, if the map is modified, the demo may no longer be valid (blank screen).
Shift F2 : opens a "Demo Playback" window to manage demos, but for me a file Load crashes Portal!
Demo Recording Tools
Console commands to record a game sequence:
record <name> : starts recording a file name.dem as soon as you exit the console (Escape key)
stop : stops recording the file which is then saved in Steam\steamapps\common\portal 2\portal2\
playdemo <name> : play the demo name.dem (the .dem file must be in the backup folder)
stopdemo : stop the demo (before the end).
Tutorial Demo Tools - Recording and playing

Videos recording
Console commands to record a video:
startmovie <name> avi : starts recording the file name.avi
endmovie : stops recording the file that is in \Steam\SteamApps\common\portal 2
This method doesn't always work well (sound problem, empty file, ...)
The other method is to use a video capture software.
It may also be easier to record a demo first, and when it's satisfactory, play it while recording it as a video (after adjusting the screen resolution).
Demo Video Creation
See also this guide: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=154183949#98362


Your map is now added to the top of Portal's Steam Workshop! ... and is quickly pushed back a few pages farther by the new maps constantly being published by other developers around the world!

The problem with this repository is its popularity. So how do you get your map tested by others?
Solution 1, Self-promotion: leave a comment (or not) on someone else's map and then add a link to your own maps -> this isn't considered good.
Solution 2: Put a tag #F4F in the description, short for Follow for follow (or Feedback for feedback), which basically means, if you test this map, I'll test one of yours.
Solution 3: Join a group to test maps within a small community.
See Portal 2 groups.
There are also forums like:
Thinking with portals[www.thinking.withportals.com] (broken)
Steam Users Forum

Guide about evaluation: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=425731057

Watch out for "Map Breakers"
Some players have "ninja" skills and can "break" a map (avoid its normal flow and reach the end very quickly) using advanced techniques such as "bunny hopping" or cube throwing.
https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=1245255994 https://youtu.be/JX3_KxTXkr4 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=2078413062 https://youtu.be/Hx3FwVZU2jw

Tens of thousands of maps have been created since PeTI was first released; the possibilities seem endless, and we're still discovering new design ideas and systems...
Yet we always want more, especially the elements found in Portal 1 and 2, but not available in the PeTI editor.
So some have created extensions: mods (Modification/Module).
PeTI has not planned to open up to "plug-ins", so extensions have some constraints; for example, they replace items choices in the palette, or requires to modifying game files. They may also no longer work after an official update of PeTI or the mod!

-BEE2 version 4 beta (Better Extended Editor 2)
Allows you to replace/add items and logical systems to the PeTI palette.
There are also settings to configure the map (styles, starting and ending rooms, music, etc.).
See https://github.com/BEEmod/BEE2.4 (two zip to download: Application and Item Packages)
https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=879065525
-Ben and August's Extended Editor (BEEMOD) (BEEMOD, Ben and Carl's Extended Editor 2) version 2 2.5 alpha[/b]
This is the ancestor of the previous mod.
Additional elements are available, such as TeamSpen210: https://github.com/TeamSpen210/tspenAddons
Discussion: https://gtm.steamproxy.vip/workshop/discussions/-1/882957083795805701/?appid=620

-Felix Griffin's Editor Mod (FGEMOD)
Like BEEMOD.
Obsolete.

-HMW
Much like the previous two.
Obsolete.

-Style changer
Allows you to give a retro look to the maps, as seen in the game Portal 2.
Discussion: https://gtm.steamproxy.vip/workshop/discussions/-1/882953189045851829/?appid=620

Guide to mods: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=125711076
The "Hammer" editor is an external tool for creating maps with all the scenery, items and behavior possibilities found in Portal 2.
Official tutorial: https://developer.valvesoftware.com/wiki/Category:Portal_2_Level_Design
It is possible to transfer a map made with PeTI to continue it in Hammer, but not vice versa.
Three guides covering maps made with PeTI:
https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=122711831 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=131864864 https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=166218120
Numerous video tutorials: https://www.tophattwaffle.com/tutorials/

A video for making items to use with PeTI editor + BEEMOD: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=635174646
A guide to getting started with Hammer: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=251265571
A series of guides: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=668125032
To go further with Hammer: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=608136553