private static GLDisplayList CreateAxes(GLContext ctx)
{
GLDisplayList list = new GLDisplayList(ctx);
list.Begin();
ctx.glBegin(GLPrimitiveType.Lines);
ctx.glColor(1.0f, 0.0f, 0.0f, 1.0f);
ctx.glVertex(0.0f, 0.0f, 0.0f);
ctx.glVertex(2.0f, 0.0f, 0.0f);
ctx.glVertex(1.0f, 0.0f, 0.0f);
ctx.glVertex(1.0f, 1.0f, 0.0f);
ctx.glVertex(1.0f, 0.0f, 0.0f);
ctx.glVertex(1.0f, 0.0f, 1.0f);
ctx.glColor(0.0f, 1.0f, 0.0f, 1.0f);
ctx.glVertex(0.0f, 0.0f, 0.0f);
ctx.glVertex(0.0f, 2.0f, 0.0f);
ctx.glVertex(0.0f, 1.0f, 0.0f);
ctx.glVertex(1.0f, 1.0f, 0.0f);
ctx.glVertex(0.0f, 1.0f, 0.0f);
ctx.glVertex(0.0f, 1.0f, 1.0f);
ctx.glColor(0.0f, 0.0f, 1.0f, 1.0f);
ctx.glVertex(0.0f, 0.0f, 0.0f);
ctx.glVertex(0.0f, 0.0f, 2.0f);
ctx.glVertex(0.0f, 0.0f, 1.0f);
ctx.glVertex(1.0f, 0.0f, 1.0f);
ctx.glVertex(0.0f, 0.0f, 1.0f);
ctx.glVertex(0.0f, 1.0f, 1.0f);
ctx.glEnd();
list.End();
return(list);
}