Welcome to the first of many SimplePlanes 2 dev blogs! We're going to be doing one of these about every couple weeks or so, sometimes more. Each one will showcase a multitude of features focused around a central theme. For this first post, the central theme will be on the map. We've got quite a lot to cover here!

Real quickly though, if you want to see individual segments of these dev blogs several days early as they're written, check out the #showcases channel in our official Discord server. We'd love to see you there :)

SP2 Discord[discord.gg]

With the preamble over with, let's get into the exciting bits :D

Something players love to do in SimplePlanes is zoom by at insane speeds, but our islands have always gone by in a blink. For SP2 we want to address many of the most common criticisms we’ve received and push things further than ever before. The new archipelago spans almost 800 km2 of highly detailed terrain both above and below the water, so even if you get the zoomies you’ll be flying over cool terrain for a little while before you find yourself lost over endless open ocean.

The archipelago consists of three main islands: on the Northern end there’s Vetusta Island, on the South there’s New Yoke Island, and separating them you’ll find Middleton. Each one is trapped in its own metaphorical time bubble, leading to very different vibes from one border to the next as you’ll get to see in future showcases.

For these new islands we tried to find a good balance between realism and terrain features that are impressive to look at while being fun to explore. In order to achieve this we have used a set of advanced tools to generate the terrain that combine the power of procedural noise, realistic erosion simulation, and high artistic freedom over the main landmass.

In this image you can see the full archipelago in its various stages as we first lay down the noise, then remap it and paint some canyons, ravines, and islets around, applying multiple erosion and weathering simulations on top of it and finishing it off by adding snow, rivers, and a few final touches before painting the different terrain textures using information from all the previous steps, such as the soil deposition and amount of erosion.

Now let’s talk about some of the tools we’re using that allow us to make our terrain look way better than before.

One of these tools is a terrain shader called MicroSplat, by Jason Booth. Without boring you too much with babble, what MicroSplat allows us to do is give our terrain more and better PBR textures along with advanced rendering techniques, all while being super performant.

For SimplePlanes 2 this means you’ll see better looking and more varied terrain than in our previous games, with more detail and without hurting performance too much.

Another big step up in visual quality that we can now take advantage of is heightmap-based texture blending. In our previous games when two textures interacted with each other they had a smooth blend of color and texture, but now the details of the rougher textures can sneak through the cracks as the blend happens, independent of the terrain resolution.

A big element that didn’t age well in SimplePlanes was how stretched some of the textures would get whenever we had a tall cliff or canyon. In SP2 we can now take advantage of a technique called Triplanar Mapping, which samples the texture from up to 3 different angles depending on its slope.

Probably one of the biggest limitations when it comes to large organic features is that the textures used result in very obvious tiling patterns as they get repeated over and over across the surface. To combat this we now have Stochastic sampling in our arsenal. At the cost of a few extra texture samples what this does is it rotates each tile at random and height blends them, entirely removing the visual tiling.

As you’ve definitely seen by now, the map is covered in trees. Not only does this help make the game prettier, it also provides a really nice (and necessary) sense of scale. Another benefit is it helps make low altitude flight feel more dangerous as the trees have colliders, which will ruin your whole day if you clip your wing while trying to be a showoff.

The main limiting factor for having a lot of vegetation is that models that look good for trees require a lot of geometry, and with how large our map is we need a LOT of them. Games usually get around this by having what’s called Levels of Detail (LODs), so as things become smaller on your screen, they switch to simplified models and sometimes even to a flat image. But simplified geometry is still too much geometry for us (despite the name of the game), and flat images look really bad as you fly by. So, what now?

Once again, the huge ecosystem of tried and true assets Unity provides is of great help, with two really good tools in particular being very handy: GPUI and Amplify Impostors.

The first asset improves how the data for the trees flows between the CPU and GPU in a similar fashion to what the Parallax mod does in Juno, but without the extra complexity of having a spherical planet with procedural terrain.

The second creates a texture that morphs depending on the view angle, faking the illusion of depth in what can only be described as magic. We collaborated with the Amplify team to test their 1.0 release for the Impostors shader to help us have zero compromises when it comes to foliage. Believe it or not, the trees in this gif are a flat image with some shader trickery!

Another huge challenge to overcome for a map the size of ours is figuring out how to place down the trees. Planting one by one may be meditative, but ain’t nobody got time for that. For this task Jason Booth comes back to the rescue with another great tool of his, MicroVerse.

This swiss army knife covers most of the flaws from the insanely underwhelming terrain tools Unity provides, and works hand in hand with MicroSplat to let us do non-destructive tweaks to the islands’ geometry, textures and vegetation interactively. For example, we can just ask it to place trees anywhere with grass, limit it to a certain altitude and slope, adjust the density and call it a day. Or even add patches of trees on demand in certain areas, in the screenshots you can see how inside of the yellow lines there have been trees added, and the blue lines are painting the terrain in dirt, and even carving it.

When you think of a large sprawling landmass many things come to mind, but I bet none of you thought of caves. Yup, that’s right, we’ve done it! Now you can go hide in a hole underground just like IRL and never see the light of day. And maybe, just maybe, leading into that hole underground is a waterfall. Believe it or not, we have one of those too!

Caves and rivers have both been highly requested features in our previous titles, but they’ve been practically impossible for us to actually implement, the caves because we couldn’t do actual holes in the terrain, and the rivers because the water could only be at sea level.

For SimplePlanes 2, though, we’ve actually been able to do it. We’ve got rivers that aren’t just flat streams of water; they flow above the sea level, and we have a giant cave you can not just explore but even fly through, if your skills allow for it.

If we’re going to have such a large map, we need a way to get you to move from one end of an island to the next, besides just flying around or having to go offroad.

To achieve this, we’ve made a huge network of highways, roads, and trails, spanning over 300 km in length across the map. If you want to get in a car and drive from one end of the Archipelago to another on a road, that’s totally doable. If you want to get lost in the mountains following a winding trail, we also have you covered – no driver’s license required, but you better get insurance.

With the help of Microverse all these roads merge with the terrain, change their textures, and clear the trees, allowing us to go crazy without having to worry about laying down asphalt by hand, even for racetracks that seamlessly blend with the environment.

• Added SimplePlanes 2 button to the SANDBOX section in the main menu
  
• Added special error dialog when attempting to load a craft made in SimplePlanes 2
  
• Updated Unity to 2022.3.41f1
  
• Fixed parachute activation expression not recognizing aircraft variables

• In the "VR headset not found..." error message, we now show the current OpenXR runtime (for debugging purposes), and a link to the related topic on the Steam forums.

• SimplePlanes VR will have a launch discount for a limited time.
  
• Once logged in, you have access to fly the same craft in both games.
  
• SimplePlanes includes an aircraft builder, SimplePlanes VR does not.
  
• Except for those which require building; all challenges, islands, locations, aircraft, etc. are available in both games.
  
• Buying them both on Steam will automatically enable VR in SimplePlanes. After VR is enabled in SimplePlanes you can do everything there, without switching games.

• Fully immersive cockpits and virtual controls that you can reach out and grab with your hands
  
• Download and fly any number of crafts from SimplePlanes.com for free
  
• Escort a bomber, torpedo a WW2 destroyer, dogfight enemy aircraft, obliterate a convoy, and several more combat challenges are included
  
• Fly around in sandbox mode and engage neutral aircraft and ships or spawn enemy aircraft to dogfight whenever it suits your fancy
  
• Explore islands and airports to unlock secret locations
  
• Includes several air and car racecourses to compete against A.I. opponents
  
• One of the very few flight sims available for Oculus Quest, and the only one that includes helicopters and such a wide variety of aircraft!

• Gauges[www.simpleplanes.com] – Instrument panel gauges used to display a piece of information (such as altitude or airspeed) with radial indicators.
  
• Artificial Horizon – A standalone artificial horizon which appears to contain a ball, but does not require a cut–out in the panel to show depth.
  
• Labels[www.simpleplanes.com] – Label parts, to add text or numbers to builds. Supports inputs within curly brackets, curvature, outline, gradients, and rich text formatting.
  
• Simple Throttle – a standalone push–pull style throttle.
  
• Fighter Throttle – a standalone slider type throttle with button.
  
• Yoke – a standalone yoke part, with two handles.
  
• Lever – a simple standalone lever that can be bound to any axis.
  
• Control Base[www.simpleplanes.com] – A part that acts as a rotator and a grippable control, grip parts such as the joystick top can be placed on top of it. Each axis it takes an input that is also its output. This means it cannot be an arbitrary FT expression, but can be a flight control or a custom variable name.
  
• Buttons – Interactable buttons that can be pushed to do stuff
  
• Switches – Interactable switches that can be toggled to do stuff
  
• Flight Computer – A 'cockpit' part with no camera that can act as a primary cockpit part.
  
• Modern Joystick – A modern–style joystick grip part with a trigger and buttons.
  
• Basic Joystick – An older looking joystick grip part with trigger and buttons.
  
• Cylinder Grip – A basic grip part in the form of a cylinder.
  
• Refuel Probe – A part that enables the “assist” mode of refueling from a drogue.
  
• Refuel Drogue – Transfers fuel to other craft, designed to be trailed on a winch. Only used on the Tanker.
  
• Seat – A simple seat part with built in camera.
  
• Advanced Seat – A stronger fighter jet style seat. May add ejection functionality in the future.
  
• Cockpit Canopy – A prebuilt glass canopy for 1–seat cockpits. Can open.
  
• Basic Frame – A skeleton for the interior of a cockpit, which everything can stick to.
  
• Modern Frame – Similar to Basic Frame, but with side areas for placing controls and a central divider between the pilot's legs.
  
• Hollow Glass – A hollow glass part with tweaked rendering so the inside is not visible from outside, and the inside can be coloured differently to the outside. Recommend turning down the smoothness in the inside, as strong reflections from the canopy do not reflect the cockpit and can be very disorienting.
  
• Wing Landing Gear Bare – new version of the wing landing gear with a different wheel and no attached fairing.

• An aircraft now has a list of numeric variables that can be written to from certain sources and read from all FT expressions.
  
• Each assignment to a variable also carries a “priority” which allows you to choose which assignments will override others if multiple attempt on the same frame.
  
• Variables are mainly written from the aircraft’s list of variable setters, which is accessible from a button in the bottom right of the designer. Each row in this isn’t a variable, but represents an assignment to a variable (a variable is automatically created if it’s ever assigned to). This means you can assign the same variable multiple times in that frame, or have it updated from multiple sources. A setter takes in an FT expression and stores its result to a variable. It also has an activator function which can disable the setter but this is XML–only right now and pending a GUI.
  
• Variables can also be written by part modifiers that have designated outputs. Currently the only one of these is a helicopter rotor that outputs its RPM to the variable
  RotorRPM
  for a gauge, but this may be expanded on in the future.

• Added emission option to paint. Emissive paint do glowy. We assume no liability for exposure to radiation.
  
• Added part hiding feature in the designer. You can conceal parts, show or hide concealed parts, invert the concealed part list, and other things.
  
• Added 5 extra color slots for default themes.
  
• Added support for Slant Angle to all fuselage parts.
  
• Maintain camera orientation when double-clicking to focus on a non-wing part.
  
• CTRL+Click on the Input button in Part Properties to enter a Funky Trees expression.
  
• Changed minimum zoom distance in the designer to from 0.5 to 0.05.
  
• Hold left-shift to pan/rotation/zoom the camera at 10% normal speed.
  
• Changed name of designer categories: "Cockpits" to "Cockpit Basic".
  
• Added XML attribute for the CowlFlaps on the WWII engine to hide the engine cowl (bool attribute is named "hide").
  
• Added support for loading AI aircraft across multiple frames.
  
• Added optional liftScale to Wing.State XML element.
  
• Added optional throttleResponse attribute to Engine.State XML element to override the part type's throttleResponse.
  
• Added "audio" XML attribute to JointRotator modifier so the annoying audio can be disabled.
  
• Added Rpm1, Rpm2, Rpm3, and Rpm4 to the flight data accessible from Funky Trees. These predate the RotorRPM variable and are on a priority based system, supporting up to 4 sources. They can't be remapped manually, but they do support Car Engines as well as heli rotors.
  
• Added collider attribute to Fuselage.State element to allow more accurate colliders on fuselage parts. Possible values are Auto, Basic, ConvexMesh, and NonConvexMesh. Note that NonConvexMesh will still be convex in flight due to physics limitations.
  
• Hold left-shift to pan/rotation/zoom the camera at 10% normal speed.
  
• Added support for custom names for cameras.
  
• Added TargetLocked and TargetLocking variables accessible from Funky Trees.
  
• Made connections more predictable when using the “Add Section” button.
  
• Updated the camera part to optionally support the gun reticle and missile targeting
  
• Updated the cockpit modifier to optionally disable the camera vantage.
  
• Updated the cameras to optionally act like a cockpit camera, using a priority based system.
  
• Updated the first person camera part to support an adjustable 'up offset'. Prior to this tweak, a hard–coded offset of 0.5 was used, meaning the camera would render half a meter above the visual mesh for the camera. This can now be adjusted. With a value of zero, the camera should render at the same position as the visual mesh.
  
• The designer paint panel now dynamically adds colors to match the number of materials defined in XML.
  
• Updated to Unity 2020.3.19