Triangle wireframe colors
When you set the surface shading to No, the wireframe will be the color of the surface. So when the surface has a color of white and has no for shading, the wireframe will be white, unless the background color is white, then they will be black.
When you set the shading to By surface color, the wireframe will be black.
When you set the shading to By elevation, the wireframe will be black.
When you select a surface, the wireframe will be the color of the highlight color.
Breaklines are shown as red unless the surface color is red then they will be black.
Drapelines are shown as the color of the surface.
Surfaces created from corridors will have most of the surface controlled by breaklines and drapelines embedded in the surface. This can cause a mix of colors.
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