GoaLitiuM/FlaxEngine
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Add improved Global SDF sampling at empty areas

Browse Source
This commit is contained in:
Wojtek Figat
2024-07-19 00:27:30 +02:00
parent 3aa8e67551
commit 3945e1416b
1 changed files with 33 additions and 28 deletions
Download Patch File Download Diff File Expand all files Collapse all files

61
Source/Shaders/GlobalSignDistanceField.hlsl
View File

@@ -65,11 +65,11 @@ struct GlobalSDFHit
}
};
void GetGlobalSDFCascadeUV(const GlobalSDFData data, uint cascade, float3 worldPosition, out float cascadeSize, out float3 cascadeUV, out float3 textureUV)
void GetGlobalSDFCascadeUV(const GlobalSDFData data, uint cascade, float3 worldPosition, out float3 cascadeUV, out float3 textureUV)
{
float4 cascadePosDistance = data.CascadePosDistance[cascade];
float3 posInCascade = worldPosition - cascadePosDistance.xyz;
cascadeSize = cascadePosDistance.w * 2;
float cascadeSize = cascadePosDistance.w * 2;
cascadeUV = saturate(posInCascade / cascadeSize + 0.5f);
textureUV = float3(((float)cascade + cascadeUV.x) / (float)data.CascadesCount, cascadeUV.y, cascadeUV.z); // Cascades are placed next to each other on X axis
}
@@ -79,9 +79,8 @@ uint GetGlobalSDFCascade(const GlobalSDFData data, float3 worldPosition)
{
for (uint cascade = 0; cascade < data.CascadesCount; cascade++)
{
float cascadeSize;
float3 cascadeUV, textureUV;
GetGlobalSDFCascadeUV(data, cascade, worldPosition, cascadeSize, cascadeUV, textureUV);
GetGlobalSDFCascadeUV(data, cascade, worldPosition, cascadeUV, textureUV);
if (all(cascadeUV > 0) && all(cascadeUV < 1))
return cascade;
}
@@ -92,13 +91,14 @@ uint GetGlobalSDFCascade(const GlobalSDFData data, float3 worldPosition)
float SampleGlobalSDFCascade(const GlobalSDFData data, Texture3D<snorm float> tex, float3 worldPosition, uint cascade)
{
float distance = GLOBAL_SDF_WORLD_SIZE;
float cascadeSize;
float3 cascadeUV, textureUV;
GetGlobalSDFCascadeUV(data, cascade, worldPosition, cascadeSize, cascadeUV, textureUV);
GetGlobalSDFCascadeUV(data, cascade, worldPosition, cascadeUV, textureUV);
float voxelSize = data.CascadeVoxelSize[cascade];
float chunkMargin = voxelSize * (GLOBAL_SDF_CHUNK_MARGIN_SCALE * GLOBAL_SDF_RASTERIZE_CHUNK_MARGIN);
float maxDistanceTex = data.CascadeMaxDistanceTex[cascade];
float distanceTex = tex.SampleLevel(SamplerLinearClamp, textureUV, 0);
if (distanceTex < GLOBAL_SDF_MIN_VALID && all(cascadeUV > 0) && all(cascadeUV < 1))
distance = distanceTex * maxDistanceTex;
float distanceTex = tex.SampleLevel(SamplerLinearClamp, textureUV, 0) * maxDistanceTex;
if (distanceTex < chunkMargin && all(cascadeUV > 0) && all(cascadeUV < 1))
distance = distanceTex;
return distance;
}
@@ -110,12 +110,13 @@ float SampleGlobalSDF(const GlobalSDFData data, Texture3D<snorm float> tex, floa
return GLOBAL_SDF_WORLD_SIZE;
for (uint cascade = 0; cascade < data.CascadesCount; cascade++)
{
float cascadeSize;
float3 cascadeUV, textureUV;
GetGlobalSDFCascadeUV(data, cascade, worldPosition, cascadeSize, cascadeUV, textureUV);
GetGlobalSDFCascadeUV(data, cascade, worldPosition, cascadeUV, textureUV);
float voxelSize = data.CascadeVoxelSize[cascade];
float chunkMargin = voxelSize * (GLOBAL_SDF_CHUNK_MARGIN_SCALE * GLOBAL_SDF_RASTERIZE_CHUNK_MARGIN);
float maxDistanceTex = data.CascadeMaxDistanceTex[cascade];
float distanceTex = tex.SampleLevel(SamplerLinearClamp, textureUV, 0);
if (distanceTex < GLOBAL_SDF_MIN_VALID && all(cascadeUV > 0) && all(cascadeUV < 1))
if (distanceTex < chunkMargin && all(cascadeUV > 0) && all(cascadeUV < 1))
{
distance = distanceTex * maxDistanceTex;
break;
@@ -132,17 +133,20 @@ float SampleGlobalSDF(const GlobalSDFData data, Texture3D<snorm float> tex, Text
return GLOBAL_SDF_WORLD_SIZE;
for (uint cascade = 0; cascade < data.CascadesCount; cascade++)
{
float cascadeSize;
float3 cascadeUV, textureUV;
GetGlobalSDFCascadeUV(data, cascade, worldPosition, cascadeSize, cascadeUV, textureUV);
GetGlobalSDFCascadeUV(data, cascade, worldPosition, cascadeUV, textureUV);
float voxelSize = data.CascadeVoxelSize[cascade];
float chunkSize = voxelSize * GLOBAL_SDF_RASTERIZE_CHUNK_SIZE;
float chunkMargin = voxelSize * (GLOBAL_SDF_CHUNK_MARGIN_SCALE * GLOBAL_SDF_RASTERIZE_CHUNK_MARGIN);
float maxDistanceMip = data.CascadeMaxDistanceMip[cascade];
float distanceMip = mip.SampleLevel(SamplerLinearClamp, textureUV, 0);
if (distanceMip < GLOBAL_SDF_MIN_VALID && all(cascadeUV > 0) && all(cascadeUV < 1))
if (distanceMip < chunkSize && all(cascadeUV > 0) && all(cascadeUV < 1))
{
distance = distanceMip * cascadeSize;
distance = distanceMip * maxDistanceMip;
float maxDistanceTex = data.CascadeMaxDistanceTex[cascade];
float distanceTex = tex.SampleLevel(SamplerLinearClamp, textureUV, 0);
if (distanceTex < GLOBAL_SDF_MIN_VALID)
distance = distanceTex * maxDistanceTex;
float distanceTex = tex.SampleLevel(SamplerLinearClamp, textureUV, 0) * maxDistanceTex;
if (distanceTex < chunkMargin)
distance = distanceTex;
break;
}
}
@@ -158,11 +162,13 @@ float3 SampleGlobalSDFGradient(const GlobalSDFData data, Texture3D<snorm float>
return gradient;
for (uint cascade = 0; cascade < data.CascadesCount; cascade++)
{
float cascadeSize;
float3 cascadeUV, textureUV;
GetGlobalSDFCascadeUV(data, cascade, worldPosition, cascadeSize, cascadeUV, textureUV);
GetGlobalSDFCascadeUV(data, cascade, worldPosition, cascadeUV, textureUV);
float voxelSize = data.CascadeVoxelSize[cascade];
float chunkMargin = voxelSize * (GLOBAL_SDF_CHUNK_MARGIN_SCALE * GLOBAL_SDF_RASTERIZE_CHUNK_MARGIN);
float maxDistanceTex = data.CascadeMaxDistanceTex[cascade];
float distanceTex = tex.SampleLevel(SamplerLinearClamp, textureUV, 0);
if (distanceTex < GLOBAL_SDF_MIN_VALID && all(cascadeUV > 0) && all(cascadeUV < 1))
if (distanceTex < chunkMargin && all(cascadeUV > 0) && all(cascadeUV < 1))
{
float texelOffset = 1.0f / data.Resolution;
float xp = tex.SampleLevel(SamplerLinearClamp, float3(textureUV.x + texelOffset, textureUV.y, textureUV.z), 0).x;
@@ -171,8 +177,8 @@ float3 SampleGlobalSDFGradient(const GlobalSDFData data, Texture3D<snorm float>
float yn = tex.SampleLevel(SamplerLinearClamp, float3(textureUV.x, textureUV.y - texelOffset, textureUV.z), 0).x;
float zp = tex.SampleLevel(SamplerLinearClamp, float3(textureUV.x, textureUV.y, textureUV.z + texelOffset), 0).x;
float zn = tex.SampleLevel(SamplerLinearClamp, float3(textureUV.x, textureUV.y, textureUV.z - texelOffset), 0).x;
gradient = float3(xp - xn, yp - yn, zp - zn) * cascadeSize;
distance = distanceTex * cascadeSize;
gradient = float3(xp - xn, yp - yn, zp - zn) * maxDistanceTex;
distance = distanceTex * maxDistanceTex;
break;
}
}
@@ -188,9 +194,8 @@ float3 SampleGlobalSDFGradient(const GlobalSDFData data, Texture3D<snorm float>
return gradient;
for (uint cascade = 0; cascade < data.CascadesCount; cascade++)
{
float cascadeSize;
float3 cascadeUV, textureUV;
GetGlobalSDFCascadeUV(data, cascade, worldPosition, cascadeSize, cascadeUV, textureUV);
GetGlobalSDFCascadeUV(data, cascade, worldPosition, cascadeUV, textureUV);
float voxelSize = data.CascadeVoxelSize[cascade];
float chunkSize = voxelSize * GLOBAL_SDF_RASTERIZE_CHUNK_SIZE;
float chunkMargin = voxelSize * (GLOBAL_SDF_CHUNK_MARGIN_SCALE * GLOBAL_SDF_RASTERIZE_CHUNK_MARGIN);
@@ -263,9 +268,9 @@ GlobalSDFHit RayTraceGlobalSDF(const GlobalSDFData data, Texture3D<snorm float>
float stepScale = trace.StepScale;
// Sample SDF
float stepDistance, cascadeSize, voxelSizeScale = (float)GLOBAL_SDF_RASTERIZE_MIP_FACTOR;
float stepDistance, voxelSizeScale = (float)GLOBAL_SDF_RASTERIZE_MIP_FACTOR;
float3 cascadeUV, textureUV;
GetGlobalSDFCascadeUV(data, cascade, stepPosition, cascadeSize, cascadeUV, textureUV);
GetGlobalSDFCascadeUV(data, cascade, stepPosition, cascadeUV, textureUV);
float distanceMip = mip.SampleLevel(SamplerLinearClamp, textureUV, 0) * maxDistanceMip;
if (distanceMip < chunkSize)
{