Add KHR_materials_clearcoat during export

code/AssetLib/glTF2/glTF2AssetWriter.h

@@ -47,6 +47,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *   KHR_materials_pbrSpecularGlossiness: full
  *   KHR_materials_unlit: full
  *   KHR_materials_sheen: full
+ *   KHR_materials_clearcoat: full
  */
 #ifndef GLTF2ASSETWRITER_H_INC
 #define GLTF2ASSETWRITER_H_INC

code/AssetLib/glTF2/glTF2AssetWriter.inl

@@ -436,6 +436,28 @@ namespace glTF2 {
             }
         }
 
+        if (m.materialClearcoat.isPresent) {
+            Value materialClearcoat(rapidjson::Type::kObjectType);
+
+            MaterialClearcoat &clearcoat = m.materialClearcoat.value;
+
+            if (clearcoat.clearcoatFactor != 0.f) {
+                WriteFloat(materialClearcoat, clearcoat.clearcoatFactor, "clearcoatFactor", w.mAl);
+            }
+
+            if (clearcoat.clearcoatRoughnessFactor != 0.f) {
+                WriteFloat(materialClearcoat, clearcoat.clearcoatRoughnessFactor, "clearcoatRoughnessFactor", w.mAl);
+            }
+
+            WriteTex(materialClearcoat, clearcoat.clearcoatTexture, "clearcoatTexture", w.mAl);
+            WriteTex(materialClearcoat, clearcoat.clearcoatRoughnessTexture, "clearcoatRoughnessTexture", w.mAl);
+            WriteTex(materialClearcoat, clearcoat.clearcoatNormalTexture, "clearcoatNormalTexture", w.mAl);
+                        
+            if (!materialClearcoat.ObjectEmpty()) {
+                exts.AddMember("KHR_materials_clearcoat", materialClearcoat, w.mAl);
+            }
+        }
+
         if (!exts.ObjectEmpty()) {
             obj.AddMember("extensions", exts, w.mAl);
         }
@@ -831,6 +853,10 @@ namespace glTF2 {
             if (this->mAsset.extensionsUsed.KHR_materials_sheen) {
                 exts.PushBack(StringRef("KHR_materials_sheen"), mAl);
             }
+                        
+            if (this->mAsset.extensionsUsed.KHR_materials_clearcoat) {
+                exts.PushBack(StringRef("KHR_materials_clearcoat"), mAl);
+            }
         }
 
         if (!exts.Empty())

code/AssetLib/glTF2/glTF2Exporter.cpp

@@ -730,6 +730,23 @@ void glTF2Exporter::ExportMaterials()
 
             m->materialSheen = Nullable<MaterialSheen>(sheen);
         }
+
+        bool hasMaterialClearcoat = false;
+        mat->Get(AI_MATKEY_GLTF_MATERIAL_CLEARCOAT, hasMaterialClearcoat);
+
+        if (hasMaterialClearcoat) {
+            mAsset->extensionsUsed.KHR_materials_clearcoat= true;
+
+            MaterialClearcoat clearcoat;
+
+            mat->Get(AI_MATKEY_GLTF_MATERIAL_CLEARCOAT_FACTOR, clearcoat.clearcoatFactor);
+            mat->Get(AI_MATKEY_GLTF_MATERIAL_CLEARCOAT_ROUGHNESS_FACTOR, clearcoat.clearcoatRoughnessFactor);
+            GetMatTex(mat, clearcoat.clearcoatTexture, AI_MATKEY_GLTF_MATERIAL_CLEARCOAT_TEXTURE);
+            GetMatTex(mat, clearcoat.clearcoatRoughnessTexture, AI_MATKEY_GLTF_MATERIAL_CLEARCOAT_ROUGHNESS_TEXTURE);
+            GetMatTex(mat, clearcoat.clearcoatNormalTexture, AI_MATKEY_GLTF_MATERIAL_CLEARCOAT_NORMAL_TEXTURE);
+
+            m->materialClearcoat = Nullable<MaterialClearcoat>(clearcoat);
+        }
     }
 }