What is the difference between Front/Back Face Color in MaterialMappingControl class?

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1

I’m not sure what the difference is. If you have any references or explanations, please let me know.

2

Hello @mini,

The functions SetFrontFaceColor and SetBackFaceColor allow you to specify separate colors for the two sides of a shell. Since polygon handedness and culling determine how the front and back faces are rendered, ensure that you have set those parameters appropriately. Below is a sample code:

void CHPSView::OnUserCode2()
{
	SegmentKey model_key = GetCanvas().GetAttachedLayout().GetAttachedView().GetAttachedModel().GetSegmentKey();
	SegmentKey quad_key = model_key.Subsegment("quad");
	quad_key.GetDrawingAttributeControl().SetPolygonHandedness(HPS::Drawing::Handedness::Right);
	quad_key.GetCullingControl().SetBackFace(false);

	quad_key.GetMaterialMappingControl().SetFrontFaceColor(HPS::RGBAColor(1, 0, 0)); //set front face color to red
	quad_key.GetMaterialMappingControl().SetBackFaceColor(HPS::RGBAColor(0, 1, 0)); //set back face color to green

	Point points[4] = { Point(-0.5, -0.5, 0), Point(0.5, -0.5, 0), Point(0.5, 0.5, 0), Point(-0.5, 0.5, 0) };
	int faceList[5] = { 4, 0, 1, 2, 3 };

	quad_key.InsertShell(4, points, 5, faceList);

	_canvas.UpdateWithNotifier().Wait();
}

Here is the result:
forum_post

Thanks,
Tino