Trade: *MaterialData::hasTextureCoordinates() returns false when it's 0.

All other classes were fixed to do the same as Phong. Plus the docs were
clarified for PbrClearCoatMaterialData.

src/Magnum/Trade/FlatMaterialData.cpp

@@ -44,9 +44,9 @@ bool FlatMaterialData::hasTextureTransformation() const {
 }
 
 bool FlatMaterialData::hasTextureCoordinates() const {
-    return (hasAttribute(MaterialAttribute::BaseColorTexture) && hasAttribute(MaterialAttribute::BaseColorTextureCoordinates)) ||
-        (hasAttribute(MaterialAttribute::DiffuseTexture) && hasAttribute(MaterialAttribute::DiffuseTextureCoordinates)) ||
-        hasAttribute(MaterialAttribute::TextureCoordinates);
+    return (hasAttribute(MaterialAttribute::BaseColorTexture) && attributeOr(MaterialAttribute::BaseColorTextureCoordinates, 0u)) ||
+        (hasAttribute(MaterialAttribute::DiffuseTexture) && attributeOr(MaterialAttribute::DiffuseTextureCoordinates, 0u)) ||
+        attributeOr(MaterialAttribute::TextureCoordinates, 0u);
 }
 
 Color4 FlatMaterialData::color() const {

src/Magnum/Trade/PbrClearCoatMaterialData.cpp

@@ -67,11 +67,11 @@ bool PbrClearCoatMaterialData::hasCommonTextureTransformation() const {
 }
 
 bool PbrClearCoatMaterialData::hasTextureCoordinates() const {
-    return hasAttribute(MaterialAttribute::LayerFactorTextureCoordinates) ||
-        hasAttribute(MaterialAttribute::RoughnessTextureCoordinates) ||
-        hasAttribute(MaterialAttribute::NormalTextureCoordinates) ||
-        hasAttribute(MaterialAttribute::TextureCoordinates) ||
-        hasAttribute(0, MaterialAttribute::TextureCoordinates);
+    return attributeOr(MaterialAttribute::LayerFactorTextureCoordinates, 0u) ||
+        attributeOr(MaterialAttribute::RoughnessTextureCoordinates, 0u) ||
+        attributeOr(MaterialAttribute::NormalTextureCoordinates, 0u) ||
+        attributeOr(MaterialAttribute::TextureCoordinates, 0u) ||
+        attributeOr(0, MaterialAttribute::TextureCoordinates, 0u);
 }
 
 bool PbrClearCoatMaterialData::hasCommonTextureCoordinates() const {

src/Magnum/Trade/PbrClearCoatMaterialData.h

@@ -119,8 +119,9 @@ class MAGNUM_TRADE_EXPORT PbrClearCoatMaterialData: public MaterialLayerData<Mat
          * @ref MaterialAttribute::RoughnessTextureCoordinates,
          * @ref MaterialAttribute::NormalTextureCoordinates or
          * @ref MaterialAttribute::TextureCoordinates attributes are present in
-         * this material or if @ref MaterialAttribute::TextureCoordinates is
-         * present in the base material, @cpp false @ce otherwise.
+         * this material and have a non-zero value or if
+         * @ref MaterialAttribute::TextureCoordinates is present in the base
+         * material and has a non-zero value, @cpp false @ce otherwise.
          */
         bool hasTextureCoordinates() const;
 

src/Magnum/Trade/PbrMetallicRoughnessMaterialData.cpp

@@ -157,13 +157,13 @@ bool PbrMetallicRoughnessMaterialData::hasCommonTextureTransformation() const {
 }
 
 bool PbrMetallicRoughnessMaterialData::hasTextureCoordinates() const {
-    return hasAttribute(MaterialAttribute::TextureCoordinates) ||
-        hasAttribute(MaterialAttribute::BaseColorTextureCoordinates) ||
-        hasAttribute(MaterialAttribute::MetalnessTextureCoordinates) ||
-        hasAttribute(MaterialAttribute::RoughnessTextureCoordinates) ||
-        hasAttribute(MaterialAttribute::NormalTextureCoordinates) ||
-        hasAttribute(MaterialAttribute::OcclusionTextureCoordinates) ||
-        hasAttribute(MaterialAttribute::EmissiveTextureCoordinates);
+    return attributeOr(MaterialAttribute::TextureCoordinates, 0u) ||
+        attributeOr(MaterialAttribute::BaseColorTextureCoordinates, 0u) ||
+        attributeOr(MaterialAttribute::MetalnessTextureCoordinates, 0u) ||
+        attributeOr(MaterialAttribute::RoughnessTextureCoordinates, 0u) ||
+        attributeOr(MaterialAttribute::NormalTextureCoordinates, 0u) ||
+        attributeOr(MaterialAttribute::OcclusionTextureCoordinates, 0u) ||
+        attributeOr(MaterialAttribute::EmissiveTextureCoordinates, 0u);
 }
 
 bool PbrMetallicRoughnessMaterialData::hasCommonTextureCoordinates() const {

src/Magnum/Trade/PbrSpecularGlossinessMaterialData.cpp

@@ -91,13 +91,13 @@ bool PbrSpecularGlossinessMaterialData::hasCommonTextureTransformation() const {
 }
 
 bool PbrSpecularGlossinessMaterialData::hasTextureCoordinates() const {
-    return hasAttribute(MaterialAttribute::TextureCoordinates) ||
-        hasAttribute(MaterialAttribute::DiffuseTextureCoordinates) ||
-        hasAttribute(MaterialAttribute::SpecularTextureCoordinates) ||
-        hasAttribute(MaterialAttribute::GlossinessTextureCoordinates) ||
-        hasAttribute(MaterialAttribute::NormalTextureCoordinates) ||
-        hasAttribute(MaterialAttribute::OcclusionTextureCoordinates) ||
-        hasAttribute(MaterialAttribute::EmissiveTextureCoordinates);
+    return attributeOr(MaterialAttribute::TextureCoordinates, 0u) ||
+        attributeOr(MaterialAttribute::DiffuseTextureCoordinates, 0u) ||
+        attributeOr(MaterialAttribute::SpecularTextureCoordinates, 0u) ||
+        attributeOr(MaterialAttribute::GlossinessTextureCoordinates, 0u) ||
+        attributeOr(MaterialAttribute::NormalTextureCoordinates, 0u) ||
+        attributeOr(MaterialAttribute::OcclusionTextureCoordinates, 0u) ||
+        attributeOr(MaterialAttribute::EmissiveTextureCoordinates, 0u);
 }
 
 bool PbrSpecularGlossinessMaterialData::hasCommonTextureCoordinates() const {