SEGA SATURN DEVELOPER'S MANUAL

Specifies color calculation. Color calculation is effective when the non-texture color is in RGB mode. Specify Replace if you do not want to perform color calculation. When performing Gouraud shading processing, specify the Gouraud shading table address divided by 8H. Gouraud shading is effective when the non-texture color is in RGB mode. Only vertex (A) and vertex (B) in the Gouraud shading table are valid, and vertex (C) and vertex (D) are ignored.
Define the vertex (A) of the line to be drawn as CMDXA, CMDYA and the vertex (B) as CMDXB, CMDYB.
Supplement: If two vertices are set to the same coordinate, the line is drawn with one pixel.