yep its still slow even with limiting the number of traces and doing block pixel setting ( took 3-4 seconds at 640x480 with that image above.)

but thats all i did, was base color shade on the traced distance


vec_set(temp.x, vector(xx, yy, 10000));
vec_for_screen(temp.x, camera);

trace_hit = c_trace(camera.x, temp.x,ignore_me);
if (trace_hit !=0)
{
i = int((1-trace_hit/10000)*255);
vec_set(color,vector(i,i,i));

then just translate that color vector to a pixel and plot it back onto the image

I think shaders could do this faster as you can grab everything in the render view with one shot. but i don't know shaders to do such a thing myself.

it would be possible via dll or scripting, but you'd have to use an example of OLD 3D rendering to pull it off. a single line of traces , then vector math calculations to set where evrything is and its hight. then blit the data into the image all at one time vs the pixel by pixel drawing method.