livie
/
phoenix-firestorm
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

#4109 Use correct GLTF coordinate system rotation

meow-7.2.2
Andrey Lihatskiy 2025-05-23 01:08:58 +03:00
parent f5d4d3f862
commit d713be4bbe
1 changed files with 18 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
indra/newview/gltf/llgltfloader.cpp
View File

@ -176,6 +176,7 @@ bool LLGLTFLoader::parseMeshes()
LLMatrix4 node_matrix(glm::value_ptr(node.mMatrix));
LLMatrix4 node_transform;
node_transform *= coord_system_rotation; // Apply coordinate rotation first
node_transform *= node_matrix;
// Examine all primitives in this mesh
@ -261,25 +262,24 @@ bool LLGLTFLoader::parseMeshes()
// This will make sure the matrix is always valid from the node.
node.makeMatrixValid();
LLMatrix4 gltf_transform = LLMatrix4(glm::value_ptr(node.mMatrix));
mTransform = gltf_transform;
// GLTF is +Y up, SL is +Z up
mTransform *= coord_system_rotation;
mTransform.setIdentity();
transformation = mTransform;
// adjust the transformation to compensate for mesh normalization
LLVector3 mesh_scale_vector;
LLVector3 mesh_translation_vector;
pModel->getNormalizedScaleTranslation(mesh_scale_vector, mesh_translation_vector);
LLMatrix4 mesh_translation;
mesh_translation.setTranslation(mesh_translation_vector);
mesh_translation *= transformation;
transformation = mesh_translation;
LLMatrix4 mesh_scale;
mesh_scale.initScale(mesh_scale_vector);
mesh_scale *= transformation;
transformation = mesh_scale;
if (transformation.determinant() < 0)
{ // negative scales are not supported
LL_INFOS("GLTF") << "Negative scale detected, unsupported post-normalization transform. domInstance_geometry: "
@ -471,10 +471,16 @@ bool LLGLTFLoader::populateModelFromMesh(LLModel* pModel, const LL::GLTF::Mesh&
glm::mat4 combined_transform;
computeCombinedNodeTransform(mGLTFAsset, node_index, combined_transform);
// Create coordinate system rotation matrix - GLTF is Y-up, SL is Z-up
glm::mat4 coord_system_rotation = glm::rotate(glm::mat4(1.0f), glm::radians(90.0f), glm::vec3(1.0f, 0.0f, 0.0f));
// Apply coordinate system rotation to the combined transform
combined_transform = coord_system_rotation * combined_transform;
// Apply the global scale and center offset to all vertices
for (U32 i = 0; i < prim.getVertexCount(); i++)
{
// Transform vertex position with combined hierarchy transform
// Transform vertex position with combined hierarchy transform (including coord rotation)
glm::vec4 pos(prim.mPositions[i][0], prim.mPositions[i][1], prim.mPositions[i][2], 1.0f);
glm::vec4 transformed_pos = combined_transform * pos;
@ -486,7 +492,11 @@ bool LLGLTFLoader::populateModelFromMesh(LLModel* pModel, const LL::GLTF::Mesh&
(transformed_pos.z + center_offset.mV[VZ]) * scale_factor
);
vert.normal = glm::vec3(prim.mNormals[i][0], prim.mNormals[i][1], prim.mNormals[i][2]);
// Also rotate the normal vector
glm::vec4 normal_vec(prim.mNormals[i][0], prim.mNormals[i][1], prim.mNormals[i][2], 0.0f);
glm::vec4 transformed_normal = coord_system_rotation * normal_vec;
vert.normal = glm::normalize(glm::vec3(transformed_normal));
vert.uv0 = glm::vec2(prim.mTexCoords0[i][0], -prim.mTexCoords0[i][1]);
if (skinIdx >= 0)