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konstatoivanenkonstatoivanen
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implement volumetric fog.
1 parent 9d4da27 commit b0f7fc7

20 files changed

+405
-7
lines changed

‎PKRenderer/PKRenderer.vcxproj‎

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@@ -546,6 +546,7 @@ Call "$(SolutionDir)Build\PKAssetTools.exe" "'$(ProjectDir)res\'" "'$(TargetDir)
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<ClInclude Include="src\Core\Services\AssetDatabase.h" />
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<ClInclude Include="src\ECS\Contextual\Engines\EngineDebug.h" />
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<ClInclude Include="src\ECS\Contextual\Engines\EnginePKAssetBuilder.h" />
549+
<ClInclude Include="src\Rendering\Passes\PassVolumeFog.h" />
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<ClInclude Include="src\Rendering\Passes\PassGeometry.h" />
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<ClInclude Include="src\Rendering\Passes\PassLights.h" />
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<ClInclude Include="src\Rendering\Passes\PassSceneGI.h" />
@@ -807,18 +808,23 @@ Call "$(SolutionDir)Build\PKAssetTools.exe" "'$(ProjectDir)res\'" "'$(TargetDir)
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<None Include="res\models\MDL_Columns.mdl" />
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<None Include="res\models\MDL_Spiral.mdl" />
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<None Include="res\shaders\CS_SceneGI_Bake.shader" />
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<None Include="res\shaders\CS_VolumeFogDepthMax.shader" />
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<None Include="res\shaders\CS_VolumeFogLightDensity.shader" />
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<None Include="res\shaders\CS_VolumeFogScatter.shader" />
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<None Include="res\shaders\includes\Blit.glsl" />
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<None Include="res\shaders\includes\ClusterIndexing.glsl" />
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<None Include="res\shaders\includes\Common.glsl" />
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<None Include="res\shaders\includes\Constants.glsl" />
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<None Include="res\shaders\includes\Encoding.glsl" />
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<None Include="res\shaders\includes\BRDF.glsl" />
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<None Include="res\shaders\includes\Reconstruction.glsl" />
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<None Include="res\shaders\includes\SharedVolumeFog.glsl" />
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<None Include="res\shaders\includes\SharedLights.glsl" />
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<None Include="res\shaders\includes\SharedSceneGI.glsl" />
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<None Include="res\shaders\includes\SharedShadowmapping.glsl" />
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<None Include="res\shaders\includes\SharedSurfaceShading.glsl" />
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<None Include="res\shaders\CS_SceneGI_Mipmap.shader" />
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<None Include="res\shaders\SH_VS_VolumeFogComposite.shader" />
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<None Include="res\shaders\SH_WS_PBR_Cloth.shader" />
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<None Include="res\shaders\includes\Utilities.glsl" />
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<None Include="res\shaders\includes\Lighting.glsl" />
@@ -908,6 +914,7 @@ Call "$(SolutionDir)Build\PKAssetTools.exe" "'$(ProjectDir)res\'" "'$(TargetDir)
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<ClCompile Include="src\Core\Services\Input.cpp" />
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<ClCompile Include="src\ECS\Contextual\Engines\EngineDebug.cpp" />
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<ClCompile Include="src\ECS\Contextual\Engines\EnginePKAssetBuilder.cpp" />
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<ClCompile Include="src\Rendering\Passes\PassVolumeFog.cpp" />
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<ClCompile Include="src\Rendering\Passes\PassGeometry.cpp" />
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<ClCompile Include="src\Rendering\Passes\PassLights.cpp" />
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<ClCompile Include="src\Rendering\Passes\PassSceneGI.cpp" />

‎PKRenderer/PKRenderer.vcxproj.filters‎

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@@ -1401,6 +1401,9 @@
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<ClInclude Include="src\Rendering\Passes\PassSceneGI.h">
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<Filter>Header Files</Filter>
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</ClInclude>
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<ClInclude Include="src\Rendering\Passes\PassVolumeFog.h">
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<Filter>Header Files</Filter>
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</ClInclude>
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</ItemGroup>
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<ItemGroup>
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<None Include="include\glm\detail\func_common.inl">
@@ -1912,6 +1915,11 @@
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<None Include="res\shaders\CS_SceneGI_Mipmap.shader" />
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<None Include="res\shaders\includes\SharedSceneGI.glsl" />
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<None Include="res\shaders\CS_SceneGI_Bake.shader" />
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<None Include="res\shaders\includes\SharedVolumeFog.glsl" />
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<None Include="res\shaders\CS_VolumeFogDepthMax.shader" />
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<None Include="res\shaders\CS_VolumeFogLightDensity.shader" />
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<None Include="res\shaders\CS_VolumeFogScatter.shader" />
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<None Include="res\shaders\SH_VS_VolumeFogComposite.shader" />
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</ItemGroup>
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<ItemGroup>
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<ClCompile Include="include\glm\detail\glm.cpp">
@@ -2130,6 +2138,9 @@
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<ClCompile Include="src\Rendering\Passes\PassSceneGI.cpp">
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<Filter>Source Files</Filter>
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</ClCompile>
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<ClCompile Include="src\Rendering\Passes\PassVolumeFog.cpp">
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<Filter>Source Files</Filter>
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</ClCompile>
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</ItemGroup>
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<ItemGroup>
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<Library Include="libs\glfw3.lib" />

‎PKRenderer/res/shaders/CS_Bloom.shader‎

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@@ -20,7 +20,7 @@ void main()
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int2 coord = int2(gl_GlobalInvocationID.xy);
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int2 size = imageSize(_DestinationTex).xy;
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if (Greater(coord, size))
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if (GEqual(coord, size))
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{
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return;
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}

‎PKRenderer/res/shaders/CS_VolumeFogDepthMax.shader‎

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@@ -0,0 +1,24 @@
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#version 460
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#pragma PROGRAM_COMPUTE
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#include includes/SharedVolumeFog.glsl
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const int2 offsets[4] = { int2(0,0), int2(0,1), int2(1,1), int2(1,0) };
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layout(local_size_x = VOLUME_DEPTH_BATCH_SIZE_PX, local_size_y = VOLUME_DEPTH_BATCH_SIZE_PX, local_size_z = 1) in;
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void main()
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{
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int2 coord = int2(gl_GlobalInvocationID.xy) * 2;
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coord.x = min(coord.x, int(pk_ScreenParams.x - 2));
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coord.y = min(coord.y, int(pk_ScreenParams.y - 2));
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float2 uv = coord * pk_ScreenParams.zw;
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float4 depths = LinearizeDepth(textureGatherOffsets(pk_ScreenDepth, uv, offsets));
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float depth = depths.x;
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depth = max(depth, depths.y);
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depth = max(depth, depths.z);
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depth = max(depth, depths.w);
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// Gathering can exceed the tile bounds by 1px. A negligible margin of error.
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atomicMax(PK_BUFFER_DATA(pk_VolumeMaxDepths, GetVolumeDepthTileIndex(uv)), floatBitsToUint(depth));
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}

‎PKRenderer/res/shaders/CS_VolumeFogLightDensity.shader‎

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@@ -0,0 +1,74 @@
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#version 460
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#pragma PROGRAM_COMPUTE
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#include includes/Lighting.glsl
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#include includes/SharedVolumeFog.glsl
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#include includes/SharedSceneGI.glsl
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float Density(float3 pos)
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{
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float fog = pk_Volume_ConstantFog;
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fog += clamp(exp(pk_Volume_HeightFogExponent * (-pos.y + pk_Volume_HeightFogOffset)) * pk_Volume_HeightFogAmount, 0.0, 1e+3f);
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float3 warp = pos;
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fog *= NoiseScroll(warp, pk_Time.y * pk_Volume_WindSpeed, pk_Volume_NoiseFogScale, pk_Volume_WindDir.xyz, pk_Volume_NoiseFogAmount, -0.3, 8.0);
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return max(fog * pk_Volume_Density, 0.0f);
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}
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float3 GetAmbientColor(float3 position, float3 direction, float3 viewdir)
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{
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float anistropy = GetLightAnisotropy(viewdir, direction, pk_Volume_Anisotropy);
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float4 scenegi = SampleGIVolumetric(position);
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float3 staticgi = SampleEnvironment(OctaUV(direction), 1.0f) * anistropy;
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return staticgi * scenegi.a + scenegi.rgb;
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}
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layout(local_size_x = 16, local_size_y = 2, local_size_z = 16) in;
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void main()
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{
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uint3 id = gl_GlobalInvocationID;
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float2 uv = (VOLUME_SIZE_ST.zz + id.xy) * VOLUME_SIZE_ST.xy;
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float zmax = VOLUME_LOAD_MAX_DEPTH(GetVolumeDepthTileIndex(uv));
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// Triangle dither range is -1.5 - 1.5 and due to trilinear interpolation we also need to have 2 texels worth of coverage.
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float zmin = GetVolumeCellDepth(id.z - 3.0f);
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float3 bluenoise = GetVolumeCellNoise(id);
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float depth = GetVolumeCellDepth(id.z + NoiseUniformToTriangle(bluenoise.x));
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// Texel is inside dither & trilinear interpolation range. Let's clamp it so that we can avoid light leaking through thin surfaces.
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if (zmin < zmax)
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{
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depth = min(zmax, depth);
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}
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depth = max(pk_ProjectionParams.x, depth);
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float3 worldpos = mul(pk_MATRIX_I_V, float4(ClipToViewPos(uv, depth), 1.0f)).xyz;
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float3 viewdir = normalize(worldpos - pk_WorldSpaceCameraPos.xyz);
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float3 color = GetAmbientColor(worldpos, normalize(bluenoise - 0.5f + float3(0, 1, 0)), viewdir);
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LightTile tile = GetLightTile(GetTileIndexUV(uv, depth));
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for (uint i = tile.start; i < tile.end; ++i)
61+
{
62+
color += GetVolumeLightColor(i, worldpos, viewdir, tile.cascade, pk_Volume_Anisotropy);
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}
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float density = Density(worldpos);
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float4 preval = tex2D(pk_Volume_InjectRead, ReprojectWorldToCoord(worldpos));
68+
float4 curval = float4(pk_Volume_Intensity * density * color, density);
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curval = lerp(preval, curval, VOLUME_ACCUMULATION);
71+
curval.a = VOLUME_MIN_DENSITY + curval.a;
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imageStore(pk_Volume_Inject, int3(id), curval);
74+
}

‎PKRenderer/res/shaders/CS_VolumeFogScatter.shader‎

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,32 @@
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#version 460
2+
#pragma PROGRAM_COMPUTE
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#include includes/SharedVolumeFog.glsl
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layout(local_size_x = 32, local_size_y = 2, local_size_z = 1) in;
6+
void main()
7+
{
8+
float4 accumulation = float4(0, 0, 0, 1);
9+
int3 pos = int3(gl_GlobalInvocationID.xy, 0);
10+
float3 vpos = ClipToViewPos((VOLUME_SIZE_ST.zz + pos.xy) * VOLUME_SIZE_ST.xy, 1.0f);
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#pragma unroll VOLUME_DEPTH
13+
for (;pos.z < VOLUME_DEPTH; ++pos.z)
14+
{
15+
float2 depths = GetVolumeCellDepth(float2(pos.z, pos.z + 1.0f));
16+
float depth = lerp(depths.x, depths.y, 0.5f);
17+
float slicewidth = depths.y - depths.x;
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float4 slice = imageLoad(pk_Volume_Inject, pos);
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float transmittance = exp(-slice.a * slicewidth);
22+
float3 lightintegral = slice.rgb * (1.0f - transmittance) / slice.a;
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accumulation.rgb += lightintegral * accumulation.a;
25+
accumulation.a *= transmittance;
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27+
float4 preval = tex2D(pk_Volume_ScatterRead, ReprojectViewToCoord(vpos * depth));
28+
float4 outval = lerp(preval, accumulation, VOLUME_ACCUMULATION);
29+
30+
imageStore(pk_Volume_Scatter, pos, outval);
31+
}
32+
}

‎PKRenderer/res/shaders/SH_VS_IBLBackground.shader‎

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Original file line numberDiff line numberDiff line change
@@ -1,4 +1,6 @@
11
#version 450
2+
#ZTest LEqual
3+
#ZWrite False
24
#include includes/Lighting.glsl
35
#include includes/Blit.glsl
46

‎PKRenderer/res/shaders/SH_VS_VolumeFogComposite.shader‎

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,33 @@
1+
#version 460
2+
#BlendColor Add One SrcAlpha
3+
#include includes/SharedVolumeFog.glsl
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#pragma PROGRAM_VERTEX
5+
#include includes/Blit.glsl
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out float4 vs_TEXCOORD;
7+
8+
void main()
9+
{
10+
vs_TEXCOORD = PK_BLIT_VERTEX_TEXCOORD.xyxy;
11+
vs_TEXCOORD = float4(vs_TEXCOORD.xy, vs_TEXCOORD.xy * pk_ScreenParams.xy + pk_Time.ww * 1000);
12+
gl_Position = PK_BLIT_VERTEX_POSITION;
13+
};
14+
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#pragma PROGRAM_FRAGMENT
16+
float SampleDepth(float2 uv)
17+
{
18+
return LinearizeDepth(tex2D(pk_ScreenDepth, uv).r);
19+
}
20+
21+
in float4 vs_TEXCOORD;
22+
out float4 SV_Target0;
23+
void main()
24+
{
25+
float d = LinearizeDepth(tex2D(pk_ScreenDepth, vs_TEXCOORD.xy).r);
26+
float w = GetVolumeWCoord(d);
27+
28+
float3 offset = GlobalNoiseBlue(int2(vs_TEXCOORD.zw));
29+
offset -= 0.5f;
30+
offset *= VOLUME_COMPOSITE_DITHER_AMOUNT;
31+
32+
SV_Target0 = tex2D(pk_Volume_ScatterRead, float3(vs_TEXCOORD.xy, w) + offset.xyz);
33+
};

‎PKRenderer/res/shaders/includes/Common.glsl‎

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Original file line numberDiff line numberDiff line change
@@ -43,6 +43,8 @@ PK_DECLARE_CBUFFER(pk_PerFrameConstants, PK_SET_GLOBAL)
4343
float4x4 pk_MATRIX_I_VP;
4444
// Last view * projection matrix.
4545
float4x4 pk_MATRIX_L_VP;
46+
// Last view * projection * current inverse view matrix;
47+
float4x4 pk_MATRIX_LD_P;
4648
// Scene reflections exposure
4749
float pk_SceneOEM_Exposure;
4850
};

‎PKRenderer/res/shaders/includes/SharedVolumeFog.glsl‎

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@@ -0,0 +1,76 @@
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#pragma once
2+
#include Common.glsl
3+
#include Noise.glsl
4+
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#define VOLUME_DEPTH 128
6+
#define VOLUME_INV_DEPTH 0.0078125f // 1.0f / 128.0f
7+
#define VOLUME_WIDTH 160
8+
#define VOLUME_HEIGHT 90
9+
#define VOLUME_SIZE_ST float3(0.00625f, 0.0111111111111111f, 0.5f) // (1.0f / 160.0f, 1.0f / 90.0f, 0.5f)
10+
#define VOLUME_COMPOSITE_DITHER_AMOUNT 2.0f * float3(0.00625f, 0.0111111111111111f, 0.0078125f)
11+
#define VOLUME_DEPTH_BATCH_SIZE_PX 16
12+
#define VOLUME_MIN_DENSITY 0.000001f
13+
#define VOLUME_ACCUMULATION clamp(20.0f * pk_DeltaTime.x, 0.01f, 1.0f)
14+
15+
PK_DECLARE_CBUFFER(pk_VolumeResources, PK_SET_SHADER)
16+
{
17+
float4 pk_Volume_WindDir;
18+
float pk_Volume_ConstantFog;
19+
float pk_Volume_HeightFogExponent;
20+
float pk_Volume_HeightFogOffset;
21+
float pk_Volume_HeightFogAmount;
22+
float pk_Volume_Density;
23+
float pk_Volume_Intensity;
24+
float pk_Volume_Anisotropy;
25+
float pk_Volume_NoiseFogAmount;
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float pk_Volume_NoiseFogScale;
27+
float pk_Volume_WindSpeed;
28+
};
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30+
PK_DECLARE_SET_SHADER uniform sampler3D pk_Volume_ScatterRead;
31+
PK_DECLARE_SET_SHADER uniform sampler3D pk_Volume_InjectRead;
32+
layout(rgba16f, set = PK_SET_SHADER) uniform image3D pk_Volume_Inject;
33+
layout(rgba16f, set = PK_SET_SHADER) uniform image3D pk_Volume_Scatter;
34+
35+
PK_DECLARE_BUFFER(uint, pk_VolumeMaxDepths, PK_SET_SHADER);
36+
37+
#define VOLUME_LOAD_MAX_DEPTH(index) uintBitsToFloat(PK_BUFFER_DATA(pk_VolumeMaxDepths, index))
38+
39+
float GetVolumeCellDepth(float index)
40+
{
41+
return pk_ProjectionParams.x * pow(pk_ExpProjectionParams.z, index / VOLUME_DEPTH);
42+
}
43+
44+
float2 GetVolumeCellDepth(float2 index)
45+
{
46+
return pk_ProjectionParams.xx * pow(pk_ExpProjectionParams.zz, index * VOLUME_INV_DEPTH);
47+
}
48+
49+
float GetVolumeWCoord(float depth)
50+
{
51+
return max(log2(depth) * pk_ExpProjectionParams.x + pk_ExpProjectionParams.y, 0.0);
52+
}
53+
54+
float3 GetVolumeCellNoise(uint3 id)
55+
{
56+
return GlobalNoiseBlue(id.xy + id.z * int2(VOLUME_WIDTH, VOLUME_HEIGHT) + int(pk_Time.w * 1000).xx);
57+
}
58+
59+
float3 ReprojectWorldToCoord(float3 worldpos)
60+
{
61+
float3 uvw = ClipToUVW(mul(pk_MATRIX_L_VP, float4(worldpos, 1.0f)));
62+
uvw.z = GetVolumeWCoord(LinearizeDepth(uvw.z));
63+
return uvw;
64+
}
65+
66+
float3 ReprojectViewToCoord(float3 viewpos)
67+
{
68+
float3 uvw = ClipToUVW(mul(pk_MATRIX_LD_P, float4(viewpos, 1.0f)));
69+
uvw.z = GetVolumeWCoord(LinearizeDepth(uvw.z));
70+
return uvw;
71+
}
72+
73+
uint GetVolumeDepthTileIndex(float2 uv)
74+
{
75+
return uint(uv.x * VOLUME_WIDTH) + VOLUME_WIDTH * uint(uv.y * VOLUME_HEIGHT);
76+
}

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