SEUS PTGI HRR Test 2.1 2021-01-21

Update "SEUS PTGI HRR Test 2.1" (Dec 21 2020) changelog:

• Fixed new issue caused by bad placeholder tonemapping that I forgot to revert (caused gross banding in dark areas)
• Fixed issue with HRR where darker areas were less responsive/had more ghosting
• Added new shader option: Post-Processing Settings > Anti-Aliasing > AA Style. Set to "Responsive" by default, which makes the AA algorithm prefer refreshing the image more quickly when changes occur. This is new functionality, I kept going back and forth on this, let me know what you think! "Stable" is the way HRR has behaved previously, which makes the AA prefer to keep history in order for a more stable image.

BLACK REFLECTIONS BUG WORKAROUND: When you first get in-game, or whenever you load a new resource pack, press F3 + R to reload the shaders. There is a bug in this version that causes off-screen geometry in reflections to appear black, doing this is a workaround for now.

I'm sorry for the long wait! It's taken a while to get things dialed in properly, the new improvements to HRR require tweaking of many parameters which can all throw each other off. That bug I mentioned above has been driving me crazy, I can't seem to fix it. At least there's a workaround.

I'll be posting a poll soon to get a general idea of what you guys think of HRR after trying out this version. This will influence whether I feel it's worth keeping as a permanent new feature or not.

This version is mostly just an improvement to HRR (Half-Resolution Rendering) tech I've been working on for a while. There are a few cool new features as well though! Here's what's new:

• Improvements to "HRR" tech: less ghosting and better image quality in general
• Parallax Occlusion Mapping, finally! This is a totally new approach to POM that I've been working on for some time. Fragment depth modification allows all kinds of cool stuff: "free" screen-space shadows (sunlight and GI), proper reprojection under motion, and displaced intersections on some blocks (depending on geometry and textures, e.g. redstone dust can look "embedded" on the block it's placed on!)
• New shader option: Surface Options > Smooth Parallax Surface. Enables interpolation of the heightmap driving displacement, leading to smooth slopes. Default: On. Let me know what you think of this
• New shader option: Anti-Aliasing > Pixel Look. Set to "Sharp" by default, which essentially does nothing. "Filmic" is the alternative setting which softens the rendered image before it's tonemapped which gives a more filmic and less video-gamey look at the cost of image clarity.
• Fixed incorrect loss of energy in secondary light bounces which caused indirect lighting to look too dark, particularly in closed spaces/interiors. These areas should look much more realistic now (especially when lighter materials make up the interior space)!
• New (work in progress) motion blur technique which properly blurs foreground motion and no longer makes HRR obvious by revealing jagged low-res edges (walking past grass or leaves close to the player shows the new improvements well)
• Reworked screen-space shadows: much more accurate and tighter shadows. Helps apparent clarity in lighting with HRR (particularly with grass and leaves) and gives nice contact shadows with POM
• Support for Minecraft 1.16. All the new blocks and light sources should properly contribute to GI. Due to a change in particle rendering, particles cannot be rendered and lit properly. Because particles are important to gameplay, I've opted to implement a placeholder way of rendering them which certainly looks incorrect, but at least they're visible.
• Improved GI diffuse filter
• AMD GPU compatibility should be fixed

PLEASE READ THE FOLLOWING REQUIREMENTS FOR USING THIS SHADER PACK!

• Minecraft 1.16.4 (older version compatibility may be present but is not guaranteed)
• OptiFine HD U G5 or newer
• Options > Video Settings > Details > Alternate Blocks: OFF
• Options > Video Settings > Details > Trees: Fancy or Fast (Smart may break lighting)
• Options > Video Settings > Quality > Natural Textures: OFF
• Options > Video Settings > Shaders > Shadow Quality: 1x
• Options > Video Settings > Shaders > Old Lighting : DEFAULT
• Resource packs with custom block models will probably cause lighting glitches!!!!!!

Some of the currently known issues are as follows:

• Particles aren't rendered properly yet, this is a 1.16 compatibility problem.
• Entities look strange when moving. This may improve if a new rendering feature is added to OptiFine.
• Block texture alpha is not considered in diffuse GI tracing, so doors and trapdoors don't let any light through their windows currently.
• Being underwater in ravines/caves shows light leaking, and “glowing” water fog. This is unavoidable currently.
• "Disco Floor" flickering artifact mostly seen in reflections (the new Secondary GI Samples option can help with this)
• Secondary GI bounces (2nd bounce and onward) can take a while to adapt to lighting changes
• Issues with the rendering of semi-transparent/translucent materials
• Lighting breaks often when using resource packs with custom models, a solution is being investigated!

AN IMPORTANT NOTE ON GRAPHICS DRIVER ISSUES AND GPU COMPATIBILITY:

Since different GPUs can compile shaders differently than others, you may experience compile errors (causes "[Shaders] Error: Invalid program..." messages to appear in the in-game chat).

If you experience compile errors and you're using an NVIDIA GPU, you can help me fix them by following the steps on this page, in the "How to Report a Compile Error" drop-down section and sending me the log!

Compatibility with AMD GPUs is being actively worked on. You will still experience some minor visual bugs, and you may experience random crashing. If you experience crashing while trying to load the game or enable SEUS PTGI, try doing so first in windowed mode, with a small window.

Compatibility with Intel GPUs is not guaranteed or planned at all!