SL-18634: Fix GLTF material texture transform not serializing when texture ID is null

indra/llprimitive/llgltfmaterial.cpp

@@ -61,6 +61,11 @@ LLMatrix3 LLGLTFMaterial::TextureTransform::asMatrix()
     return offset * rotation * scale;
 }
 
+bool LLGLTFMaterial::TextureTransform::operator==(const TextureTransform& other) const
+{
+    return mOffset == other.mOffset && mScale == other.mScale && mRotation == other.mRotation;
+}
+
 LLGLTFMaterial::LLGLTFMaterial(const LLGLTFMaterial& rhs)
 {
     *this = rhs;
@@ -268,16 +273,14 @@ void LLGLTFMaterial::writeToModel(tinygltf::Model& model, S32 mat_index) const
 
     tinygltf::Material& material_out = model.materials[mat_index];
 
-    constexpr bool is_override = false;
-
     // set base color texture
-    writeToTexture(model, material_out.pbrMetallicRoughness.baseColorTexture, GLTF_TEXTURE_INFO_BASE_COLOR, mBaseColorId, is_override, LLUUID());
+    writeToTexture(model, material_out.pbrMetallicRoughness.baseColorTexture, GLTF_TEXTURE_INFO_BASE_COLOR, mBaseColorId);
     // set normal texture
-    writeToTexture(model, material_out.normalTexture, GLTF_TEXTURE_INFO_NORMAL, mNormalId, is_override, LLUUID());
+    writeToTexture(model, material_out.normalTexture, GLTF_TEXTURE_INFO_NORMAL, mNormalId);
     // set metallic-roughness texture
-    writeToTexture(model, material_out.pbrMetallicRoughness.metallicRoughnessTexture, GLTF_TEXTURE_INFO_METALLIC_ROUGHNESS, mMetallicRoughnessId, is_override, LLUUID());
+    writeToTexture(model, material_out.pbrMetallicRoughness.metallicRoughnessTexture, GLTF_TEXTURE_INFO_METALLIC_ROUGHNESS, mMetallicRoughnessId);
     // set emissive texture
-    writeToTexture(model, material_out.emissiveTexture, GLTF_TEXTURE_INFO_EMISSIVE, mEmissiveId, is_override, LLUUID());
+    writeToTexture(model, material_out.emissiveTexture, GLTF_TEXTURE_INFO_EMISSIVE, mEmissiveId);
 
     material_out.alphaMode = getAlphaMode();
     material_out.alphaCutoff = mAlphaCutoff;
@@ -338,10 +341,11 @@ void gltf_allocate_texture_image(tinygltf::Model& model, T& texture_info, const
 }
 
 template<typename T>
-void LLGLTFMaterial::writeToTexture(tinygltf::Model& model, T& texture_info, TextureInfo texture_info_id, const LLUUID& texture_id, bool is_override, const LLUUID& base_texture_id) const
+void LLGLTFMaterial::writeToTexture(tinygltf::Model& model, T& texture_info, TextureInfo texture_info_id, const LLUUID& texture_id) const
 {
     LL_PROFILE_ZONE_SCOPED;
-    if (texture_id.isNull() || (is_override && texture_id == base_texture_id))
+    const TextureTransform& transform = mTextureTransform[texture_info_id];
+    if (texture_id.isNull() && transform == sDefault.mTextureTransform[0])
     {
         return;
     }
@@ -349,7 +353,6 @@ void LLGLTFMaterial::writeToTexture(tinygltf::Model& model, T& texture_info, Tex
     gltf_allocate_texture_image(model, texture_info, texture_id.asString());
 
     tinygltf::Value::Object transform_map;
-    const TextureTransform& transform = mTextureTransform[texture_info_id];
     transform_map[GLTF_FILE_EXTENSION_TRANSFORM_OFFSET] = tinygltf::Value(tinygltf::Value::Array({
         tinygltf::Value(transform.mOffset.mV[VX]),
         tinygltf::Value(transform.mOffset.mV[VY])

indra/llprimitive/llgltfmaterial.h

@@ -56,6 +56,8 @@ class LLGLTFMaterial : public LLRefCount
         F32 mRotation = 0.f;
 
         LLMatrix3 asMatrix();
+
+        bool operator==(const TextureTransform& other) const;
     };
 
     enum AlphaMode
@@ -149,14 +151,14 @@ class LLGLTFMaterial : public LLRefCount
     static LLVector2 getDefaultTextureScale();
     static F32 getDefaultTextureRotation();
 
-    
+
     static void hackOverrideUUID(LLUUID& id);
     static void applyOverrideUUID(LLUUID& dst_id, const LLUUID& override_id);
 
     // set mAlphaMode from string.
     // Anything otherthan "MASK" or "BLEND" sets mAlphaMode to ALPHA_MODE_OPAQUE
     void setAlphaMode(const std::string& mode, bool for_override = false);
-   
+
     const char* getAlphaMode() const;
     
     // set the contents of this LLGLTFMaterial from the given json
@@ -185,6 +187,6 @@ class LLGLTFMaterial : public LLRefCount
     void setFromTexture(const tinygltf::Model& model, const T& texture_info, TextureInfo texture_info_id, LLUUID& texture_id_out);
 
     template<typename T>
-    void writeToTexture(tinygltf::Model& model, T& texture_info, TextureInfo texture_info_id, const LLUUID& texture_id, bool is_override, const LLUUID& base_texture_id) const;
+    void writeToTexture(tinygltf::Model& model, T& texture_info, TextureInfo texture_info_id, const LLUUID& texture_id) const;
 };