Xargon/Supermodel
1
0
Fork 0
mirror of https://github.com/RetroDECK/Supermodel.git synced 2024-11-22 13:55:38 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Implement LOD blending

Browse source 
If two translucent polygons with opposing patterns overlap the result is always opaque
Also the LOD scale calculation depends on Euclidean distance of x, y and z, not just z
This commit is contained in:
gm-matthew 2023-11-16 23:03:21 +00:00
parent a065df24b8
commit ac53101214
2 changed files with 54 additions and 29 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

63
Src/Graphics/New3D/New3D.cpp
View file

@ -714,46 +714,69 @@ void CNew3D::DescendCullingNode(UINT32 addr)
}
}
float LODscale = fBlendRadius * m_nodeAttribs.currentModelScale / std::abs(m_modelMat.currentMatrix[14]);
float LODscale;
if (m_nodeAttribs.currentDisableCulling)
LODscale = FLT_MAX;
else
{
float distance = std::hypot(m_modelMat.currentMatrix[12], m_modelMat.currentMatrix[13], m_modelMat.currentMatrix[14]);
LODscale = fBlendRadius * m_nodeAttribs.currentModelScale / distance;
}
const LODFeatureType& lodTableEntry = m_LODBlendTable->table[lodTablePointer];
if (m_nodeAttribs.currentDisableCulling)
{
m_nodeAttribs.currentModelAlpha = 1.0f;
}
else
{
float nodeAlpha = lodTableEntry.lod[3].blendFactor * (LODscale - lodTableEntry.lod[3].deleteSize);
nodeAlpha = std::clamp(nodeAlpha, 0.0f, 1.0f);
m_nodeAttribs.currentModelAlpha *= nodeAlpha; // alpha of each node multiples by the alpha of its parent
}
if (m_nodeAttribs.currentClipStatus != Clip::OUTSIDE && m_nodeAttribs.currentModelAlpha > 0.0f) {
if (m_nodeAttribs.currentClipStatus != Clip::OUTSIDE && LODscale >= lodTableEntry.lod[3].deleteSize) {
// Descend down first link
if ((node[0x00] & 0x08)) // 4-element LOD table
{
lodPtr = TranslateCullingAddress(child1Ptr);
// determine which LOD to use; we do not currently blend between LODs
int modelLOD;
for (modelLOD = 0; modelLOD < 3; modelLOD++)
if (NULL != lodPtr)
{
if (LODscale >= lodTableEntry.lod[modelLOD].deleteSize)
break;
}
int modelLOD;
for (modelLOD = 0; modelLOD < 3; modelLOD++)
{
if (LODscale >= lodTableEntry.lod[modelLOD].deleteSize && lodPtr[modelLOD] & 0x1000000)
break;
}
float tempAlpha = m_nodeAttribs.currentModelAlpha;
float nodeAlpha = lodTableEntry.lod[modelLOD].blendFactor * (LODscale - lodTableEntry.lod[modelLOD].deleteSize);
nodeAlpha = std::clamp(nodeAlpha, 0.0f, 1.0f);
if (nodeAlpha > 15.0f / 16.0f) // shader discards pixels below 1/16 alpha
nodeAlpha = 1.0f;
else if (nodeAlpha < 1.0f / 16.0f)
nodeAlpha = 0.0f;
m_nodeAttribs.currentModelAlpha *= nodeAlpha; // alpha of each node multiples by the alpha of its parent
if (NULL != lodPtr) {
if ((node[0x03 - m_offset] & 0x20000000)) {
DescendCullingNode(lodPtr[modelLOD] & 0xFFFFFF);
if (nodeAlpha < 1.0f && modelLOD != 3)
{
m_nodeAttribs.currentModelAlpha = (1.0f - nodeAlpha) * tempAlpha;
DescendCullingNode(lodPtr[modelLOD+1] & 0xFFFFFF);
}
}
else {
DrawModel(lodPtr[modelLOD] & 0xFFFFFF);
if (nodeAlpha < 1.0f && modelLOD != 3)
{
m_nodeAttribs.currentModelAlpha = (1.0f - nodeAlpha) * tempAlpha;
DrawModel(lodPtr[modelLOD + 1] & 0xFFFFFF);
}
}
}
}
else {
float nodeAlpha = lodTableEntry.lod[3].blendFactor * (LODscale - lodTableEntry.lod[3].deleteSize);
nodeAlpha = std::clamp(nodeAlpha, 0.0f, 1.0f);
m_nodeAttribs.currentModelAlpha *= nodeAlpha; // alpha of each node multiples by the alpha of its parent
DescendNodePtr(child1Ptr);
}

18
Src/Graphics/New3D/R3DFrameBuffers.cpp
View file

@ -275,15 +275,17 @@ void R3DFrameBuffers::AllocShaderTrans()
vec4 colTrans1 = texture(tex1, fsTexCoord);
vec4 colTrans2 = texture(tex2, fsTexCoord);
if(colTrans1.a+colTrans2.a > 0.0) {
vec3 col1 = colTrans1.rgb * colTrans1.a;
vec3 col2 = colTrans2.rgb * colTrans2.a;
colTrans1 = vec4((col1+col2) / (colTrans1.a + colTrans2.a), // this is my best guess at the blending between the layers
colTrans1.a+colTrans2.a);
// if both transparency layers overlap, the result is opaque
if (colTrans1.a * colTrans2.a > 0.0) {
vec3 mixCol = mix(colTrans1.rgb, colTrans2.rgb, (colTrans2.a + (1.0 - colTrans1.a)) / 2.0);
fragColor = vec4(mixCol, 1.0);
}
else if (colTrans1.a > 0.0) {
fragColor = colTrans1;
}
else {
fragColor = colTrans2; // if alpha is zero it will have no effect anyway
}
fragColor = colTrans1;
}
)glsl";