Which Error shows you ure GS ??
I Making a RTS too, i have Version 6.50.6 an c_trace and vec_for_screen
works finde for me... Post the Code here..

Here one Code Snippet

Code:

	vec_for_screen(trace_start,camera);
	trace_end.x=mouse_pos.x;
	trace_end.y=mouse_pos.y;
	trace_end.z = 100000;
	vec_for_screen(trace_end,camera);
	
	
	c_trace(camera.x,trace_end,null);


cYa Sebastian

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