Update v0.25.7 “Radian Veil”

Welcome, fellow rocket scientists and pilots, to the update v0.25.7 “Radian Veil”!

At the beginning of April, I realized that the best way to continue developing the game was to fork the HDRP rendering pipeline and start making all the necessary changes directly to it. Since then, I’ve implemented several new features that I could only dream of before. This will lead to huge graphics improvements.

Volumetric Clouds

You’ve been asking for this for a long time. This was an unbelievably hard task, especially considering that Unity does not, and will not, support space simulators properly. To implement it, along with several other changes, I forked HDRP and rewrote large parts of it. And now, you can enjoy clouds from the ground.

After playing with the clouds for some time, going back to previous versions of the game felt very empty and strange.

In the air.

Flying a plane is twice as satisfying now.

And from space.

There are a lot of artifacts at those distances. It is very hard to make clouds stable on real-scale planets, but future iterations will gradually improve this.

And most importantly, it is integrated into the lighting pipeline, so cloudy areas will properly dim the light:

There are many areas on Earth completely covered by clouds.

This is the first iteration of clouds. There are a lot of artifacts, the clouds are mostly static, and they are very resource-intensive. They are also enabled only for Earth for now (Venus, I’m looking at you). But I am planning to iterate on this system, improving it with each update, just like I did with planet rendering itself.

Note: If you have performance problems, try disabling clouds or using lower cloud settings. Volumetric clouds have a very high performance cost!

Ocean

I completely reworked the ocean system and water rendering. It has physically based scattering and refraction:

It is funny that I wrote a post more than 7 years ago in which I promised good water rendering. Well, promise fulfilled!

Underwater rendering:

The camera can finally go underwater.

Caustics:

Those are light patterns on the ocean floor.

I can also change the water surface geometry in any way I like now, for example by suppressing waves near the shore:

I also tried to make shore waves, but I couldn’t come up with a stable solution at real scale. I will try again next time.

And it can even reflect the clouds:

The most important thing is that every system interacts with every other one.

Buoyancy

As I told you in the previous dev update, spacecraft can finally float in the water:

A lot of flights end up in the ocean, so this is an important part of the simulation.

They can also react to waves:

Here I am drawing a debug view of wave displacement to calculate how it will affect the floating rocket.

A foundation for reacting to water currents has also been prepared, which is very important for possible future rivers.

Space

Atmosphere rendering has been improved, and many artifacts are gone.

Those black lines in the image on the right were a pain for many years, but they were finally defeated.

Star rendering has been reworked, improving star brightness, shape, and size. More than 128,000 stars from the HIG database are now displayed:

Previously, the game supported only 65,536.

The Milky Way now uses high-resolution imagery from ESA/Gaia/DPAC.

It is not that bright in reality, but consider this an artist’s vision. It makes the space a bit less boring.

Satellites now reflect sunlight, which interacts with the atmosphere if the planet has one:

Nights will not be as dark as before during a full moon.

It is also reflected by the water:

You can even see some reflections of stars and the Milky Way on the water, but they are currently less stable. This is a Unity-side issue. Maybe adding ray-tracing support would improve it significantly.

This is also visible from orbit:

I never would have thought that making the bodies reflect sunlight would create scenes with such stunning views. I also found a photo taken from the space station showing moonlight reflecting off the ocean’s surface, and it looked very similar.

It is also worth noting that you will be able to find and see all major celestial bodies among the stars from Earth.

And finally, scaled-space and local-space atmospheric models and rendering have been unified. You can now see the atmospheres of Mars and Venus on the solar system map. Venus looks strange right now because there are no clouds, but I hope to add them in the future, so this will not be as much of a problem.

A bluish atmospheric scattering can be seen at the planet’s edges. It also gives the entire surface a slight tint.

Rocket Assembly

I’ve added an offset mode. You can offset any part in this mode. While static attachments can adjust a part’s position slightly, parts with dynamic attachments can be moved anywhere on the rocket surface where they could initially be attached.

This is especially useful for planes, allowing you to balance the center of lift perfectly.

Parts can also be slid inside other parts. This is less realistic, but it opens up much more design space. But be careful: you can’t reduce drag this way, otherwise it would become the only correct way to build rockets.

More design freedom for players!

Flight

This is another feature players have been requesting for a long time. Auto-stabilization systems can now use RCS. They also try to save as much fuel as possible. For example, if reaction wheels are operating below 20% load, RCS will not be used. Auto-stabilization will also not use RCS if time warp is above 10x because it needs to move a spacecraft into the physics simulation to do that.

It is always a good idea to attach even the smallest reaction wheel. This way, a lot of monopropellant can be saved.

Because of the extended bug-fixing period, I was not able to finish many new parts in time. For now, only two of them are ready. But I am planning to spend next month working on incoming bug reports and finishing most of those parts, so they will arrive in one of the next patches.

Full patch notes, as always, below. Thank you for playing the game and for your support. Until the next update!

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v0.25.7 Release Notes

Features:

• added volumetric clouds;
• new ocean rendering;
• implemented buoyancy;
• new star rendering + all 119,613 stars from the HIG database are now rendered;
• new Milky Way rendering;
• updated atmosphere model;
• other celestial bodies now interact with atmospheres and cast reflected light;
• scaled-space planets received atmospheres;
• [Assembly] added a part offset tool;
• improved exposure and antialiasing;
• returned SSGI and made it available in the game settings;
• implemented RCS autostabilisation;
• added FOV slider for the flight camera.

New rocket parts:

• “Traveler” Probe Core;
• Spherical Transfer Compartment;

Changes:

• Updated game engine to Unity 6.0;
• the game now stores keymaps in settings.json instead of the registry and can fall back to default mappings when they are added in the future (previously, they remained empty);
• RCS now respects resource groups and does not consume monopropellant from the entire craft while ignoring the pass-resources state of docking ports and decouplers;
• enabling resource transfer on one docking port now automatically disables it on the attached docking port to prevent race conditions;
• [Assembly] part and symmetry selections no longer reset when switching between assembly modes;
• removed unnecessary custom passes that were previously used for rendering stars and distant planets;
• scaled-space and local-space atmosphere models were unified;
• the navball no longer switches out of the target state when the distance to the target exceeds 30 km and the flight state changes;
• when the main menu is open, most input actions are ignored;
• corrected thermal conductivity calculations by fixing mistakes in the formulas;
• part volumes, areas, and voxels are automatically calculated on startup, which should make importing custom parts easier;
• control settings are now saved in settings.json instead of the registry; this allows controls to be migrated in the future and keeps the registry clean;
• added a new part category — space stations;
• improved UI rendering performance when many icons or images are used.

Part changes:

• adjusted the fuel volume of the FT-8000 Fuel Tank, FT-7990 Fuel Tank, and Side Fuel Block by approximately 5–10% to match part volume;
• deprecated the “Azimuth” and “Axis” Station Branching Modules;
• Docking Port 0: changed its shape;
• updated the model of the “Energia-C8.95” Liquid Fuel Engine (thanks to @valzay).

Settings:

• reset focus on the map was changed from backquote to Alt+Backquote to be consistent with Alt+C for resetting camera focus during flight;
• because of the above change, pause is now bound to Backquote without the Alt modifier;
• added cloud settings.

Fixes:

• probe cores losing the “control from here” flag when the pass-resources setting is changed on a docking port;
• resources still being consumed through two attached docking ports when one of them has pass resources disabled;
• an exception when trying to change something on an engine before attaching it to the rocket;
• rotation-handle synchronization on undo and redo;
• reflection-like artifacts on the planet surface when SSAO was enabled;
• Assembly: an exception when resetting a newly created rocket;
• planets losing their atmospheres when changing game settings;
• the Skycrane hole and floating disk after separation;
• an exception when switching between a rocket and a rover in flight;
• one spacecraft disappearing during docking if the other has an instrument not present on the current spacecraft;
• ocean quads flickering when moving quickly sideways at an altitude of 50 km;
• an exception when loading debris into flight mode and then switching to any other active craft;
• an exception when detaching cryocoolers when several of them are present on the rocket;
• rotation undo commands failing when several similar parts are attached to the same parent;
• spacecraft failing to load when a rocket has more than five heat shields (and probably also causing the saved game to crash);
• infinite exceptions when trying to rotate a part in some specific attachment configurations;
• quadruple symmetry not working on some attachments;
• Steam Workshop mods being impossible to disable;
• “SaHO” Probe Core module: incorrect appearance of the bottom sockets.

Known issues:

• some spacecraft could crash the game after falling into water (please send me their rocket files).