It is possible to specify the colors of the vertices. In this case, you must provide a color for all the vertices using the mesh.addColor( color ) function; for example, mesh.addColor( ofColor( 255, 0, 0 ) ). Note that in this case, the ofSetColor() function will not affect the drawing of the mesh. Remember: you should call this function as many times as you call the mesh.addVertex() function.