using gl=ManagedOpenGL.OpenGLNative; /*....*/ gl.Begin( BeginMode.Quads ); gl.TexCoord2f( 0, 1 ); gl.Vertex3f( -20, -20, 0 ); gl.TexCoord2f( 1, 1 ); gl.Vertex3f( +20, -20, 0 ); gl.TexCoord2f( 1, 0 ); gl.Vertex3f( +20, +20, 0 ); gl.TexCoord2f( 0, 0 ); gl.Vertex3f( -20, +20, 0 ); gl.End();