Material: Appearance Updates 2

Improves the use of the ShapeAppearance property for the Part workbench.

    removes DiffuseColor property
        adds Python compatibility using custom attributes
        transitions DiffuseColor to ShapeAppearance on open
    Improved UI elements for setting object appearance, and appearance per face
    Lays the foundation for future texture support

src/App/Material.cpp

@@ -25,10 +25,26 @@
 
 #ifndef _PreComp_
 #include <cstring>
+#include <random>
 #endif
 
+#include "Application.h"
 #include "Material.h"
 
+// Helper functions to consistently convert between float and long
+namespace
+{
+float fromPercent(long value)
+{
+    return std::roundf(value) / 100.0F;
+}
+
+long toPercent(float value)
+{
+    return std::lround(100.0 * value);
+}
+}  // namespace
+
 using namespace App;
 
 
@@ -317,4 +333,47 @@ void Material::setType(MaterialType MatType)
             break;
     }
 }
+
+App::Material Material::getDefaultAppearance()
+{
+    ParameterGrp::handle hGrp =
+        App::GetApplication().GetParameterGroupByPath("User parameter:BaseApp/Preferences/View");
+
+    auto getColor = [hGrp](const char* parameter, App::Color& color) {
+        uint32_t packed = color.getPackedRGB();
+        packed = hGrp->GetUnsigned(parameter, packed);
+        color.setPackedRGB(packed);
+    };
+    auto intRandom = [](int min, int max) -> int {
+        static std::mt19937 generator;
+        std::uniform_int_distribution<int> distribution(min, max);
+        return distribution(generator);
+    };
+
+    App::Material mat(App::Material::DEFAULT);
+    mat.transparency = fromPercent(hGrp->GetInt("DefaultShapeTransparency", 0));
+    long shininess = toPercent(mat.shininess);
+    mat.shininess = fromPercent(hGrp->GetInt("DefaultShapeShininess", shininess));
+
+    // This is handled in the material code when using the object appearance
+    bool randomColor = hGrp->GetBool("RandomColor", false);
+
+    // diffuse color
+    if (randomColor) {
+        float red = static_cast<float>(intRandom(0, 255)) / 255.0F;
+        float green = static_cast<float>(intRandom(0, 255)) / 255.0F;
+        float blue = static_cast<float>(intRandom(0, 255)) / 255.0F;
+        mat.diffuseColor = App::Color(red, green, blue);
+    }
+    else {
+        // Color = (204, 204, 230) = 3435980543UL
+        getColor("DefaultShapeColor", mat.diffuseColor);
+    }
+
+    getColor("DefaultAmbientColor", mat.ambientColor);
+    getColor("DefaultEmissiveColor", mat.emissiveColor);
+    getColor("DefaultSpecularColor", mat.specularColor);
+
+    return mat;
+}
 // NOLINTEND(cppcoreguidelines-avoid-magic-numbers,readability-magic-numbers)