cinera_handmade.network/cmuratori/hero/code/code574.hmml

173 lines
16 KiB
Plaintext
Raw Permalink Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

[video output=day574 member=cmuratori stream_platform=twitch stream_username=handmade_hero project=code title="Experimenting with Voxel Filters" vod_platform=youtube id=NK8sJfl6o18 annotator=Miblo]
[0:01][Recap and set the stage for the day making the ray caster produce a stable set of inputs to pass to the light field interpolater, with thoughts on multiple light fields][:lighting :speech]
[5:25][Show the current state of the :lighting][:run]
[7:11][Show the current state of the :lighting, without filling in negative light values][:run]
[7:35][Consult our :lighting TODOs][:research]
[8:03][Show the absence of light flickering, thanks to our switch to floats][:lighting :run]
[9:02][Reorganise and consult our :lighting TODOs]
[9:28][Demo our need to flood fill the voxel so that unsampled portions get filled in from nearby samples][:filtering :lighting :run]
[12:03][Consider where is most appropriate to perform the flood filled interpolation][:filtering :lighting :speech]
[13:04][Consider whether or not the reconstructed edge :lighting values should persist across frames][:filtering :lighting :run]
[15:22][Consider our options for flood filling the :lighting voxel: 1) Persistently in lighting_solution; 2) In EndLightingComputation() when: a) pushing the cells to the graphics card each frame; b) accumulating light contribution over time][:filtering :research]
[19:13][Determine to make EndLightingComputation() flood fill the :lighting voxel when pushing the cells to the graphics card][:filtering :research]
[20:36][Seperable Filters][:blackboard :filtering]
[25:03][Cache implications of our light voxel[ref
site=WikiChip
page="Core i7-7700K - Intel"
url=https://en.wikichip.org/wiki/intel/core_i7/i7-7700k]][:lighting :memory :research]
[30:44][Propose constraining our flood fill filter to cells predetermined to require :filtering][:filtering :lighting :memory :research]
[32:35][Abortively augment game_render_commands with a FloodIndices array][:filtering :lighting]
[35:54][Begin to make EndLightingComputation() flood fill the :lighting voxel with purple when pushing the cells to the graphics card, asserting that we're well inside the hot region][:filtering :lighting]
[38:17][Try unsuccessfully to trigger our hot region assertions][:filtering :lighting :run]
[39:02][Make EndLightingComputation() flood fill out to neighbour cells, introducing HasLight() and FloodLight()][:filtering :lighting]
[1:02:58][Directional Flood Filling][:blackboard :filtering :lighting]
[1:04:28][Fix FloodLight() to correctly fill in positive and negative directions, before welding its code in to EndLightingComputation()][:filtering :lighting]
[1:08:22][Check out our partially working flood filling][:filtering :lighting :run]
[1:08:52][Make EndLightingComputation() flood fill with purple][:"debug visualisation" :filtering :lighting]
[1:09:23][Check out our purple flood filling, and spot some erroneously unlit / interpolated areas][:filtering :lighting :run]
[1:10:28][Make CompileZBiasProgram() clamp the light to 0, introducing Clamp0Inf()[ref
site="OpenGL Registry"
page="The OpenGL Shading Language 1.50 Quick Reference Card"
url=https://www.khronos.org/files/opengl-quick-reference-card.pdf]][:filtering :lighting]
[1:14:37][Still see dead zones][:filtering :lighting :run]
[1:15:49][Make CompileZBiasProgram() normalise the LightN][:filtering :lighting]
[1:16:12][Still see dead zones][:filtering :lighting :run]
[1:17:21][Prevent EndLightingComputation() from flood filling with purple][:"debug visualisation" :filtering :lighting]
[1:17:27][Still see dead zones][:filtering :lighting :run]
[1:17:46][Toggle on the purple in EndLightingComputation()][:"debug visualisation" :filtering :lighting]
[1:17:48][Change HasLight() to base its decision on LightC, rather than LightN][:filtering :lighting]
[1:18:22][Still see dead zones][:filtering :lighting :run]
[1:19:13][Make EndLightingComputation() flood fill with yellow the cells that have light][:"debug visualisation" :filtering :lighting]
[1:19:49][Find that all cells are lit either purple or yellow][:"debug visualisation" :filtering :lighting :run]
[1:20:11][Comment out the yellow in EndLightingComputation()][:"debug visualisation" :filtering :lighting]
[1:20:18][See our dead zones return][:filtering :lighting :run]
[1:20:45][Make HasLight() less permissive with a threshold][:filtering :lighting]
[1:21:50][See our dead zones flood to purple (i.e. unlit)][:filtering :lighting :run]
[1:22:36][Toggle off the purple in EndLightingComputation()][:"debug visualisation" :filtering :lighting]
[1:23:00][Check out the interpolation across the light boundaries][:filtering :lighting :run]
[1:23:40][Scrutinise the directional flood fill interpolation code in EndLightingComputation()][:filtering :lighting :research]
[1:25:12][Directional Flood Fill Interpolation][:blackboard :filtering :lighting]
[1:26:33][Scrutinise the light value lookup and clamping in CompileZBiasProgram()][:filtering :lighting :research]
[1:28:41][Closely look at the apparent interpolation bug][:filtering :lighting :run]
[1:30:19][Make EndLightingComputation() flood fill purple if the LightWeight is 0][:"debug visualisation" :filtering :lighting]
[1:30:42][See some erroneously purple areas][:filtering :lighting :run]
[1:31:31][Scrutinise EndLightingComputation() for gather bugs][:filtering :lighting :research]
[1:32:12][Closely look at the erroneously purple areas][:filtering :lighting :run]
[1:32:41][Remove the threshold from HasLight() and ensure that EndLightingComputation() can blend down to 0][:filtering :lighting]
[1:34:35][Still see our interpolation artifacts][:filtering :lighting :run]
[1:36:10][Toggle off the final flood filling in EndLightingComputation()][:filtering :lighting]
[1:36:23][Still see our interpolation artifacts][:filtering :lighting :run]
[1:36:58][Try making EndLightingComputation() regularise our light normals][:filtering :lighting]
[1:37:20][See no interpolation bugs][:filtering :lighting :run]
[1:37:50][Toggle on the final flood filling in EndLightingComputation()][:filtering :lighting]
[1:38:06][See some very bizarre half-lit artifacts][:filtering :lighting :run]
[1:39:19][Investigate our half-lit artifacts][:filtering :lighting :research]
[1:40:26][Toggle off the whole flood filling code in EndLightingComputation()][:filtering :lighting]
[1:40:40][Check out our :lighting without flood filling, and spot some discontinuity across a wall][:filtering :run]
[1:41:29][Try making EndLightingComputation() regularise our light normals as 0, 0, 1][:filtering :lighting]
[1:42:04][Find that this doesn't help us][:filtering :lighting :run]
[1:42:11][Try making EndLightingComputation() regularise our light normals as 0, -1, 0][:filtering :lighting]
[1:42:23][Find that our discontinuity has gone][:filtering :lighting :run]
[1:42:33][Let EndLightingComputation() compute each voxel's normal][:filtering :lighting]
[1:42:44][Wonder if the discontinuity is due to the normal interpolation being unable to properly swing][:filtering :lighting :run]
[1:42:57][Make CompileZBiasProgram() visualise the normal][:"debug visualisation" :filtering :lighting]
[1:44:11][Determine that we are getting a 0, 0, 0 normal][:filtering :lighting :run]
[1:44:51][Prevent CompileZBiasProgram() from normalising the normal][:filtering :lighting]
[1:45:13][Find that the hard-edged 0, 0, 0 normal remains][:filtering :lighting :run]
[1:45:21][Make GetIrradiance() in CompileZBiasProgram() always visualise the normals][:"debug visualisation" :filtering :lighting]
[1:46:34][Find that the hard-edged 0, 0, 0 normal is gone][:filtering :lighting :run]
[1:46:51][Explain the problem when the light and world normals are orthogonal][:filtering :lighting :research]
[1:47:43][Make GetIrradiance() in CompileZBiasProgram() modify its result by the LightDC, and not visualise the normal][:filtering :lighting]
[1:48:16][Find that our discontinuity remains][:filtering :lighting :run]
[1:48:44][Make GetIrradiance() in CompileZBiasProgram() visualise the normal, modified by the LightDC][:"debug visualisation" :filtering :lighting]
[1:49:29][Find that our discontinuity remains][:filtering :lighting :run]
[1:49:58][Make GetIrradiance() in CompileZBiasProgram() visualise the LightDC][:"debug visualisation" :filtering :lighting]
[1:50:36][See our discontinuity][:filtering :lighting :run]
[1:50:49][Ponder our discontinuity][:filtering :lighting :research]
[1:51:50][Disable trilinear interpolation in OpenGLInit()][:hardware :lighting :rendering]
[1:52:20][Check out our non-interpolated LightDC][:filtering :lighting :run]
[1:53:20][Scrutinise GetIrradiance()][:filtering :lighting :research]
[1:54:27][Make GetIrradiance() in CompileZBiasProgram() visualise the normal][:"debug visualisation" :filtering :lighting]
[1:54:55][See smooth interpolation][:filtering :lighting :run]
[1:55:01][Make CompileZBiasProgram() visualise just the normal, without the textures][:"debug visualisation" :filtering :lighting]
[1:55:25][Check out our normals, with no or at least less discontinuity][:"debug visualisation" :filtering :lighting :run]
[1:57:30][Let CompileZBiasProgram() use the textures and not visualise the normals][:"debug visualisation" :filtering :lighting]
[1:57:39][Check out our discontinuity][:filtering :lighting :run]
[1:58:03][Temporarily make CompileZBiasProgram() hard set the LightDC to 0.5][:filtering :lighting]
[1:58:22][Find that our discontinuity has gone][:filtering :lighting :run]
[1:59:25][Let CompileZBiasProgram() gather in some light from perpendicular sources][:filtering :lighting]
[1:59:52][Find that our discontinuity has really gone][:filtering :lighting :run]
[2:01:10][Re-enable the flood filling code in EndLightingComputation()][:filtering :lighting]
[2:01:29][See that our flood filling brightens the light][:filtering :lighting :run]
[2:01:48][Prevent EndLightingComputation() from hard setting the normal to 0, 0, 1][:filtering :lighting]
[2:02:30][See that our flood filling fills in some areas][:filtering :lighting :run]
[2:03:23][Take a close look at our flood filling][:filtering :lighting :run]
[2:04:29][Respecify HasLight() as a smoothly varying GetLightAmount() for EndLightingComputation() to use as a multiplier][:filtering :lighting]
[2:07:58][Find that our flood fill's popping artifacts have been fixed][:filtering :lighting :run]
[2:08:47][Make SpamVoxel() spam out to all voxel slices][:filtering :lighting]
[2:09:27][Check out the spamming (with flood filling)][:filtering :lighting :run]
[2:09:58][Toggle off the flood filling in EndLightingComputation()][:filtering :lighting]
[2:10:08][Check out the spamming (without flood filling)][:filtering :lighting :run]
[2:11:17][Find that the spamming does not capture negative light properly in the outdoor area][:filtering :lighting :run]
[2:11:38][Prevent SpamVoxelSlice() from clamping the light's distance falloff to 0 to 1][:filtering :lighting]
[2:11:57][See that we're still not getting negative light interpolation][:filtering :lighting :run]
[2:12:50][Prevent EndLightingComputation() from clamping the light values][:filtering :lighting]
[2:13:53][See that we're still not getting negative light interpolation][:filtering :lighting :run]
[2:14:24][Scan the code for any more 0-clamping][:filtering :lighting :research]
[2:15:40][Make CompileZBiasProgram() draw negative values in red][:"debug visualisation" :filtering :lighting]
[2:16:22][See no negative values][:filtering :lighting :run]
[2:16:44][Scan the code for any more 0-clamping][:filtering :lighting :research]
[2:18:06][Add an assertion in SpamVoxelSlice that LightDF >= 0.0f][:filtering :lighting]
[2:18:37][Fail to hit that assertion][:filtering :lighting :run]
[2:18:43][Scrutinise the LightDF calculation in SpamVoxelSlice()][:filtering :lighting :research]
[2:20:50][:Run the game afresh and successfully hit our assertion in SpamVoxelSlice()][:filtering :lighting :run]
[2:20:53][Comment out the assertion in SpamVoxelSlice()][:filtering :lighting]
[2:21:07][Take another look at our non-interpolation of negative light][:filtering :lighting :run]
[2:21:44][Make TestCastFromProbes() fall-off the light more steeply][:filtering :lighting]
[2:21:57][Admire our steeper light falloff, and wonder where our stair-step pattern is coming from][:filtering :lighting :run]
[2:23:03][Prevent CompileZBiasProgram() from drawing negative values in red][:"debug visualisation" :filtering :lighting]
[2:23:12][Consider our entire falloff to not be that smooth][:filtering :lighting :run]
[2:23:35][Try making SpamVoxelSlice() set the light's alpha to the LightDF squared][:filtering :lighting]
[2:24:33][Admire our ring of light falloff][:filtering :lighting :run]
[2:24:51][Make SpamVoxelSlice() preserve the sign of the LightDF][:filtering :lighting]
[2:25:03][Check out our hard light falloff][:filtering :lighting :run]
[2:25:18][Try making SpamVoxelSlice() set the light's alpha to the LightDF square-root][:filtering :lighting]
[2:25:32][Check out our hard light falloff][:filtering :lighting :run]
[2:25:38][Revert SpamVoxelSlice() to setting the light's alpha to the LightDF][:filtering :lighting]
[2:25:51][Check out our hard light falloff][:filtering :lighting :run]
[2:26:04][Determine that we are doing ShaderSimTexWriteSRGB][:filtering :lighting :research]
[2:27:45][Temporarily prevent CompileZBiasProgram() from square-rooting the SurfaceReflect][:filtering :lighting]
[2:28:12][See that our light falloff is much smoother][:filtering :lighting :run]
[2:28:29][Revert CompileZBiasProgram() to square-rooting the SurfaceReflect, and try making SpamVoxelSlice() set the LightDist to LightN squared][:filtering :lighting]
[2:29:32][See a bizarrely octagonal light falloff][:filtering :lighting :run]
[2:29:41][Our problem: The falloff interpolation is being interpreted linearly][:filtering :lighting :research]
[2:31:13][Revert SpamVoxelSlice() to not square the LightN, and instead make GetIrradiance() in CompileZBiasProgram() square the LightV when setting the LightColor, introducing Square()][:filtering :lighting]
[2:32:53][Make SpamVoxelSlice() square the LightN when setting the LightDist, and GetIrradiance() in CompileZBiasProgram() preserve the sign[ref
site="OpenGL Registry"
page="The OpenGL Shading Language 1.50 Quick Reference Card"
url=https://www.khronos.org/files/opengl-quick-reference-card.pdf]][:filtering :lighting]
[2:35:12][See our brighter light][:filtering :lighting :run]
[2:36:30][Fix the sign-preservation in GetIrradiance() in CompileZBiasProgram()][:filtering :lighting]
[2:36:44][See our falloff][:filtering :lighting :run]
[2:37:13][Make SpamVoxelSlice() square-root the LightC0, introducing SignedSquareRoot()][:filtering :lighting]
[2:38:23][Admire our softer falloff][:filtering :lighting :run]
[2:38:38][Make TestCastFromProbes() fall-off the light more gradually][:filtering :lighting]
[2:39:03][Admire our softer, yet wobbly falloff][:filtering :lighting :run]
[2:39:36][Make TestCastFromProbes() darken the LightC][:filtering :lighting]
[2:39:45][Admire our darker light, but doubt that the falloff is softer][:filtering :lighting :run]
[2:41:00][Make TestCastFromProbes() further darken the LightC][:filtering :lighting]
[2:41:03][Admire our darker light][:filtering :lighting :run]
[2:41:26][Toggle off the square-rooting / squaring][:filtering :lighting]
[2:42:03][Check out our less gradual light falloff][:filtering :lighting :run]
[2:42:52][Make TestCastFromProbes() brighten the LightC][:filtering :lighting]
[2:43:04][Check out our brighter and less gradual light falloff][:filtering :lighting :run]
[2:44:16][Q&A][:speech]
[2:44:49][@cemuzunlar][Q: Solution->HasCornerI.x + X + 2*dZ]
[2:45:10][Fix typo in EndLightingComputation() and toggle on the flood filling][:filtering :lighting]
[2:45:25][Check out the blotchy flood filling][:filtering :lighting :run]
[2:46:15][Toggle off flood filling][:filtering :lighting]
[2:46:23][Consider our flood filling not to be close to working][:filtering :lighting :run]
[2:47:04][@0lpbm][Damn, it wasn't that][:filtering :lighting]
[2:48:29][Wrap it up][:speech]
[/video]