October 2023 Progress Update

Another busy month behind the scenes, let’s get into it.

Gonna let dotModded take over this months Focal update in it’s entirety, plus some news about Continuum RT!

Focal Engine news and progress update! I’ve personally have been moving for the last week, however that doesn’t mean progress hasn’t been made!

To start, let’s talk about Minecraft’s game versions and Alpha. We have had to come up with a new Focal development environment that we hope will massively speed up development time for updates moving forward. For the next few weeks Focal Alpha will be our highest priority, getting it out to new game versions, and hopefully facilitating smoother updates for our shaders over the next year until Focal VK is released.

These changes to Focal Alpha will also mark the start of us bringing some new features to Continuum RT. After the updates to Focal Alpha are complete, we will be working on giving RT some pretty good performance gains and the ability to trace more rays every frame. We will also be investigating noncubic geometry through AABB intersection checks, aided by the new performance uplift.

To understand how we plan to accomplish this uplift in RT you’ll need some background on how it currently traces. We are using a voxel octree built into the shadowmap texture, similarly to how other shaders accomplish this in Minecraft. We then trace a tree of rays for every pixel in a fragment shader in a massive for loop properly handling the blending and ray interactions as we accumulate more and more bounces.

Moving forward we will be doing things a little differently, the octree stays the same, however we’re breaking up tracing into multiple stages to improve cache locality and reduce branching. The new system will utilize bins to store information about which rays need to be traced next, then we use indirect compute and memory barriers to allow maximum GPU throughput with nearly no stalled cores. This reduces branching and increases performance. Giving us the ability to continue tracing rays in subsequent stages, and open up the possibility for screen space tracing to take some load off the voxel tracer; by estimating if the ray will stay within the screen. Or falling back to AABB intersections for noncubics without RT extensions. These are possibilities and not current implementations, however this is what we’re thinking about for the future of RT over the next year or so.

Thank you all again for the continued support and I can’t wait to show you all what we’re working on!

No Continuum 2.1 update made it out this month, but we did identify a specular lighting issue tied to newer game versions larger buildable world height, and corrected it. It was a fairly niche issue that would mostly effect users on superflat worlds, but seeing as our resident texture dev; Mythical, has a penchant for doing just that, we wanted to get it fixed up.

This fix was still in testing by the time update day rolled around though, so we could only release the Continuum 2.0.5 hotfix we had prepared, which just fixes another edge case issue causing some black artifacts to flash on screen for a short period at sunset when using the ultra preset or the cloud shadow setting enabled by that preset.

More to come, soon™