Motion Blur

From GameStudio Wiki

This is some cheap looking motion blur effect which doesn´t need a shader. Render to texture is needed and it is slower than the same effect would be with a shader. It can be used for some quite good looking radial blur. just activate the effect and change the views arc parameter.

//////////////////////////////////////////////////
////////////Motion Blur without Shader////////////
//////////////////////////////////////////////////
////11.08.2008////////////////by Nils Daumann/////
/////////////slindev.wordpress.com////////////////
//////////////////////////////////////////////////

var WS_MotionBlur_active = 0;


//starts the radial blur
void WS_MotionBlur_init(VIEW* view, var steps, var distance)
{
	WS_MotionBlur_active = 1;
	
	var n;
	BMAP** bmaps = malloc(sizeof(BMAP*)*steps);
	PANEL** panels = malloc(sizeof(PANEL*)*steps);
	
	for(n = 0; n < steps; n++)
	{
		bmaps[n] = bmap_createblack(screen_size.x,screen_size.y,24);
		panels[n] = pan_create("",n);
		panels[n].bmap = bmaps[n];
		set(panels[n],VISIBLE|TRANSLUCENT);
		panels[n].alpha = 100/steps;
	}
	
	n = 0;
	while(WS_MotionBlur_active)
	{
		view.bmap = bmaps[n];
		n += 1;
		n %= steps;
		wait(-distance);
	}
	
	view.bmap = 0;
	for(n = 0; n < steps; n++)
	{
		ptr_remove(panels[n]);
		ptr_remove(bmaps[n]);
	}
}

//removes the effect
void WS_MotionBlur_remove()
{
	WS_MotionBlur_active = 0;
}

This is an example on how to use it for radial blur:

//activate the effect
WS_MotionBlur_init(camera,10,0.05);
		
var i = 0;
while(i < 50)
{
	i += 10*time_step;
	camera.arc = 60-i;
	wait(1);
}

while(i > 0)
{
	i -= 5*time_step;
	camera.arc = 60-i;
	wait(1);
}

//deactivate the effect
WS_MotionBlur_remove();

--Slin 12:58, 12 August 2008 (CEST)