Two objects displayed approximately at the same location in 3D can be mixed depending on the viewpoint and the distance from the eye: this is due to the Z depth precision. When two triangles with two different colors are displayed at the same location in 3D, the two
colors are mixed. This is what we call Z-fighting which is due to the 3D OpenGL
renderer: But when the two triangles have the same vertices, only one color is displayed since it is exactly the same triangle which is displayed twice. The color of the last triangle displayed prevails over the rest. For instance, let's suppose two superimposed faces, a blue one and a red one:
Z-fighting may be reduced by activating the Flickering reduction option. |