i was bored so i tried to write an ambient occlusion render script.



it doesn't really work well but maybe someone wants to improve it.

Code:

---

bmap b_canvas = <canvas.tga>; // use the same size as screen resolution

panel pnl_canvas
{
	bmap = b_canvas;
}

function render()
{
	pnl_canvas.visible = on;

	randomize();

	var yy = 0;
	while(yy < screen_size.y)
	{
		var format;
		format = bmap_lock(b_canvas, 0);
		
		var xx = 0;
		while(xx < screen_size.x)
		{
			vec_set(temp, vector(xx, yy, 10000));
			vec_for_screen(temp, camera);
			c_trace(camera.x, temp, 0);
			
			var color[3];
			
			if(trace_hit)
			{
				var hits = 0;
				var rays = 5; // increase for less noise

				var i = 0;
				while(i < rays)
				{
					var from[3];
					var to[3];
					
					vec_set(from, target);
					vec_add(from, normal); // some offset
					
					vec_set(to, normal);
					vec_rotate(to, vector(random(180) - 90, random(180) - 90, 0)); // hemisphere?
					vec_normalize(to, 10000);
					vec_add(to, target);
					
					c_trace(from, to, 0);
					
					if(trace_hit)
					{
						hits += 1;
					}
					
					i += 1;
				}
				var shade;
				shade = int((1 - (hits / rays)) * 255);
				vec_set(color, vector(shade, shade, shade));
			}
			else
			{
				vec_set(color, vector(255, 255, 255));
			}

			var pixel;
			pixel = pixel_for_vec(color, 100, format);
			pixel_to_bmap(b_canvas, xx, yy, pixel);
			
			xx += 1;
		}
		
		bmap_unlock(b_canvas);
		
		yy += 1;
		wait(1);
	}
}

on_r = render;

---

What is that trying to do other than add noise?

Nothing
but isn't noise enough?

it's supposed to calculate "realistic" outdoor lighting with soft shadows like on an overcast day. ...the updated screenshot has some post blur added.

It sort of looks like night vision. Maybe you could make everything look green and use it as a night vision script.

i don;t seem to bealbe to make the proper TGA file for this script. give example or proper steps ( I can't figure out how to apply ANY alpha channel to a tga)

Look's great on your screen! (Without motion!)

But, how is the framerate, and how does the scene look without the effect?

it's not meant to be realtime. the above screen took about 15 seconds to render for 640x480 and 8 rays per pixel. it was just an experiment. ambient occlusion is a kind of fake global illumination method you can also use with the renderers of tools like maya. i thought it maybe would be nice to record animations with 3dgs and then output movies with this method but getting good results without too much noise is harder than i thought. of course you could also mix in the textures of the geometry. it could also be used to bake the shadows into textures.

the tga just has to be 24bit and the same size as your screen resolution.

k well i tried 24 bit tga, even differnt colors. screen just turns black as it rolls progresses down the screen.

must be my video card or some thing.

ok couldn't seem to get your script working, but after i butchered it up
i got a semi versionish of it.



Hers is what i did to the script to at least get the above results ( just changed how the color vector was set for the differnt colors)

its based on the trace distance result for color intensity

Code:

---

 

bmap b_canvas = <canvas.tga>; // use the same size as screen resolution

panel pnl_canvas
{
	bmap = b_canvas;
	flags = refresh;
}

function render()
{
	me = player;
	var color[3];
   var trace_hit;
   var xx;
   var i;
   var pixel;
	randomize();
var format;
	var yy = 0;
	while(yy < screen_size.y)
	{
		pnl_canvas.visible = on;
		format = bmap_lock(b_canvas, 0);
		xx = 0;
		while(xx < screen_size.x)
		{
			vec_set(temp.x, vector(xx, yy, 2000));
			vec_for_screen(temp.x, camera);
			trace_hit = c_trace(camera.x, temp.x,ignore_me);
			
			if (trace_hit !=0)
			{
				i = (1-trace_hit/2000)*255;
				i = int(i);
				vec_set(color,vector(i,i,i));
			}
			else
			{
				i = 255;
				vec_set(color,vector(i,i,i));	
			}
			pixel = pixel_for_vec(color, 100, format);
			pixel_to_bmap(b_canvas, xx, yy, pixel);
			xx += 1;
		}
		bmap_unlock(b_canvas);
		yy += 1;
		wait(1);
	}	
}

on_r = render;

 

---

can get sort of close to your results be adjusting how the color intensity is calcualted based on distance



mabey to make it run even faster and get the pixelation effect could set blocks of pixels. start on row 1 and skip every other row on teh screen then fill in the surrounding pixels example
instead of setting xx,yy for every pixel, take a page from interlace monitors.
start on second row of pixels

0123-> Y = 0
0123-> Y = 1
0123-> Y = 2

so start X = 1 Y = 1
fill
0,0 1,0 2,0
0,1 1,1 2,1
0,2 1,2 2,2

all in one shot

so XX and YY increments would be XX+=3 YY +=3