fteqw/engine/gl/gl_bloom.c

/*
Copyright (C) 1997-2001 Id Software, Inc.

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/
// gl_bloom.c: 2D lighting post process effect


/*
info about bloom algo:
bloom is basically smudging.
screen is nearest-downsampled to some usable scale and filtered to remove low-value light (this is what stops non-bright stuff from blooming)
this filtered image is then downsized multiple times
the downsized image is then blured 
the downsized images are then blured horizontally, and then vertically.
final pass simply adds each blured level to the original image.
all samples are then added together for final rendering (with some kind of tone mapping if you want proper hdr).

note: the horizontal/vertical bluring is a guassian filter
note: bloom comes from the fact that the most downsampled image doesn't have too many pixels. the pixels that it does have are spread over a large area.

http://prideout.net/archive/bloom/ contains some sample code
*/


//http://www.quakesrc.org/forums/viewtopic.php?t=4340&start=0

#include "quakedef.h"

#ifdef GLQUAKE
#include "shader.h"
#include "glquake.h"
cvar_t		r_bloom = CVARAFD("r_bloom", "0", "gl_bloom", CVAR_ARCHIVE, "Enables bloom (light bleeding from bright objects)");
static shader_t *bloomfilter;
static shader_t *bloomrescale;
static shader_t *bloomblur;
static shader_t *bloomfinal;

#define MAXLEVELS 3
texid_t scrtex;
texid_t pingtex[2][MAXLEVELS];
static int scrwidth, scrheight;
static int texwidth[MAXLEVELS], texheight[MAXLEVELS];



void GLBE_RenderToTexture(texid_t sourcecol, texid_t sourcedepth, texid_t destcol, texid_t destdepth, qboolean usedepth);

void R_BloomRegister(void)
{
	Cvar_Register (&r_bloom, "bloom");
}
static void R_SetupBloomTextures(int w, int h)
{
	int i, j;
	char name[64];
	if (w == scrwidth && h == scrheight)
		return;
	scrwidth = w;
	scrheight = h;
	w /= 2;
	h /= 2;
	for (i = 0; i < MAXLEVELS; i++)
	{
		w /= 2;
		h /= 2;
		/*I'm paranoid*/
		if (w < 4)
			w = 4;
		if (h < 4)
			h = 4;

		texwidth[i] = w;
		texheight[i] = h;
	}

	/*we should be doing this outside of this code*/
	if (!TEXVALID(scrtex))
		scrtex = GL_AllocNewTexture("", scrwidth, scrheight);
	GL_MTBind(0, GL_TEXTURE_2D, scrtex);
	qglTexImage2D (GL_TEXTURE_2D, 0, GL_RGBA, scrwidth, scrheight, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
	/*top level uses nearest sampling*/
	qglTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
	qglTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
	qglTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
	qglTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

	/*now create textures for each level*/
	for (j = 0; j < MAXLEVELS; j++)
	{
		for (i = 0; i < 2; i++)
		{
			if (!TEXVALID(pingtex[i][j]))
			{
				sprintf(name, "***bloom*%c*%i***", 'a'+i, j);
				TEXASSIGN(pingtex[i][j], GL_AllocNewTexture(name, texwidth[j], texheight[j]));
			}
			GL_MTBind(0, GL_TEXTURE_2D, pingtex[i][j]);
			qglTexImage2D (GL_TEXTURE_2D, 0, GL_RGBA, texwidth[j], texheight[j], 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);

			qglTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
			qglTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
			qglTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
			qglTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
		}
	}


	bloomfilter = R_RegisterShader("bloom_filter",
		"{\n"
			"cull none\n"
			"program bloom_filter\n"
			"{\n"
				"map $sourcecolour\n"
			"}\n"
		"}\n");
	bloomrescale = R_RegisterShader("bloom_rescale",
		"{\n"
			"cull none\n"
			"program default2d\n"
			"{\n"
				"map $sourcecolour\n"
			"}\n"
		"}\n");
	bloomblur = R_RegisterShader("bloom_blur",
		"{\n"
			"cull none\n"
			"program bloom_blur\n"
			"{\n"
				"map $sourcecolour\n"
			"}\n"
		"}\n");
	bloomfinal = R_RegisterShader("bloom_final",
		"{\n"
			"cull none\n"
			"program bloom_final\n"
			"{\n"
				"map $sourcecolour\n"
			"}\n"
			"{\n"
				"map $diffuse\n"
			"}\n"
			"{\n"
				"map $loweroverlay\n"
			"}\n"
			"{\n"
				"map $upperoverlay\n"
			"}\n"
		"}\n");
	bloomfinal->defaulttextures.base			= pingtex[0][0];
	bloomfinal->defaulttextures.loweroverlay	= pingtex[0][1];
	bloomfinal->defaulttextures.upperoverlay	= pingtex[0][2];
}
void R_BloomBlend (void)
{
	int i;

	if (!gl_config.ext_framebuffer_objects)
		return;
	if (!gl_config.arb_shader_objects)
		return;

	/*whu?*/
	if (!r_refdef.pxrect.width || !r_refdef.pxrect.height)
		return;

	GL_Set2D(false);

	/*update textures if we need to resize them*/
	R_SetupBloomTextures(r_refdef.pxrect.width, r_refdef.pxrect.height);

	/*grab the screen, because we failed to do it earlier*/
	GL_MTBind(0, GL_TEXTURE_2D, scrtex);
	qglCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, r_refdef.pxrect.x, r_refdef.pxrect.y - r_refdef.pxrect.height, r_refdef.pxrect.width, r_refdef.pxrect.height);

	/*filter the screen into a downscaled image*/
	GLBE_RenderToTexture(scrtex, r_nulltex, pingtex[0][0], r_nulltex, false);
	qglViewport (0, 0, texwidth[0], texheight[0]);
	R2D_ScalePic(0, vid.height, vid.width, -(int)vid.height, bloomfilter);
	/*and downscale that multiple times*/
	for (i = 1; i < MAXLEVELS; i++)
	{
		GLBE_RenderToTexture(pingtex[0][i-1], r_nulltex, pingtex[0][i], r_nulltex, false);
		qglViewport (0, 0, texwidth[i], texheight[i]);
		R2D_ScalePic(0, vid.height, vid.width, -(int)vid.height, bloomrescale);
	}

	/*gaussian filter the mips to bloom more smoothly*/
	for (i = 0; i < MAXLEVELS; i++)
	{
		/*must be 1.2th of a pixel*/
		r_worldentity.glowmod[0] = 1.2 / texwidth[i];
		r_worldentity.glowmod[1] = 0;
		GLBE_RenderToTexture(pingtex[0][i], r_nulltex, pingtex[1][i], r_nulltex, false);
		qglViewport (0, 0, texwidth[i], texheight[i]);
		R2D_ScalePic(0, vid.height, vid.width, -(int)vid.height, bloomblur);
	}
	for (i = 0; i < MAXLEVELS; i++)
	{
		r_worldentity.glowmod[0] = 0;
		r_worldentity.glowmod[1] = 1.2 / texheight[i];
		GLBE_RenderToTexture(pingtex[1][i], r_nulltex, pingtex[0][i], r_nulltex, false);
		qglViewport (0, 0, texwidth[i], texheight[i]);
		R2D_ScalePic(0, vid.height, vid.width, -(int)vid.height, bloomblur);
	}

	GL_Set2D(false);

	/*combine them onto the screen*/
	GLBE_RenderToTexture(scrtex, r_nulltex, r_nulltex, r_nulltex, false);
	R2D_ScalePic(r_refdef.vrect.x, r_refdef.vrect.y + r_refdef.vrect.height, r_refdef.vrect.width, -r_refdef.vrect.height, bloomfinal);
}
void R_InitBloomTextures(void)
{
	bloomfilter = NULL;
	bloomblur = NULL;
	bloomfinal = NULL;
	scrwidth = 0, scrheight = 0;

	if (!gl_config.ext_framebuffer_objects)
		return;

}

#elif defined(GLQUAKE)
#include "glquake.h"

/*
==============================================================================

						LIGHT BLOOMS

==============================================================================
*/

cvar_t		r_bloom = CVARAFD("r_bloom", "0", "gl_bloom", CVAR_ARCHIVE, "Enables bloom (light bleeding from bright objects)");
cvar_t		r_bloom_alpha = CVAR("r_bloom_alpha", "0.5");
cvar_t		r_bloom_diamond_size = CVAR("r_bloom_diamond_size", "8");
cvar_t		r_bloom_intensity = CVAR("r_bloom_intensity", "1");
cvar_t		r_bloom_darken = CVAR("r_bloom_darken", "3");
cvar_t		r_bloom_sample_size = CVARF("r_bloom_sample_size", "256", CVAR_RENDERERLATCH);
cvar_t		r_bloom_fast_sample = CVARF("r_bloom_fast_sample", "0", CVAR_RENDERERLATCH);

typedef struct {
	//texture numbers
	texid_t	tx_screen;	/*a copy of the screen*/
	texid_t tx_effect;	/*blured copy of bright pixels*/
	texid_t tx_backup;	/*a copy of the screen to replace the pixels that we'll clobber. FIXME: use a FBO instead*/
	texid_t tx_downsample;

	//the viewport dimensions
	int vp_x;
	int vp_y;
	int vp_w;
	int vp_h;

	//texture coordinates of screen data inside screentexture
	float scr_s;
	float scr_t;

	//dimensions of the screen texture (power of two)
	int scr_w;
	int scr_h;

	//downsampled dimensions (will always be smaller than viewport)
	int smp_w;
	int smp_h;
	//tex coords to be used for the sample
	float smp_s;
	float smp_t;

	int size_downsample;
	int size_backup;
	int size_sample;
} bloomstate_t;

static bloomstate_t bs;

//this macro is in sample size workspace coordinates
#define R_Bloom_SamplePass( xpos, ypos )				\
	qglBegin(GL_QUADS);									\
	qglTexCoord2f(	0,					bs.smp_t);		\
	qglVertex2f(	xpos,				ypos);			\
	qglTexCoord2f(	0,					0);				\
	qglVertex2f(	xpos,				ypos+bs.smp_h);	\
	qglTexCoord2f(	bs.smp_s,			0);				\
	qglVertex2f(	xpos+bs.smp_w,		ypos+bs.smp_h);	\
	qglTexCoord2f(	bs.smp_s,			bs.smp_t);		\
	qglVertex2f(	xpos+bs.smp_w,		ypos);			\
	qglEnd();

#define R_Bloom_Quad( x, y, width, height, textwidth, textheight )	\
	qglBegin(GL_QUADS);												\
	qglTexCoord2f(	0,			textheight);						\
	qglVertex2f(	x,			y);									\
	qglTexCoord2f(	0,			0);									\
	qglVertex2f(	x,			y+height);							\
	qglTexCoord2f(	textwidth,	0);									\
	qglVertex2f(	x+width,	y+height);							\
	qglTexCoord2f(	textwidth,	textheight);						\
	qglVertex2f(	x+width,	y);									\
	qglEnd();



/*
=================
R_Bloom_InitBackUpTexture
=================
*/
void R_Bloom_InitBackUpTexture(int widthheight)
{
	qbyte	*data;

	data = Z_Malloc(widthheight * widthheight * 4);

	bs.size_backup = widthheight;
	bs.tx_backup = GL_LoadTexture32("***bs.tx_backup***", bs.size_backup, bs.size_backup, (unsigned int*)data, IF_NOMIPMAP|IF_NOALPHA|IF_NOGAMMA);

	Z_Free (data);
}

/*
=================
R_Bloom_InitEffectTexture
=================
*/
void R_Bloom_InitEffectTexture(void)
{
	qbyte	*data;
	float	bloomsizecheck;

	if (r_bloom_sample_size.value < 32)
		Cvar_SetValue (&r_bloom_sample_size, 32);

	//make sure bloom size is a power of 2
	bs.size_sample = min(r_bloom_sample_size.value, gl_max_size.value);
	bloomsizecheck = (float)bs.size_sample;
	while (bloomsizecheck > 1.0f) bloomsizecheck /= 2.0f;
	if (bloomsizecheck != 1.0f)
	{
		bs.size_sample = 32;
		while (bs.size_sample < r_bloom_sample_size.value)
			bs.size_sample *= 2;
	}

	//make sure bloom size doesn't have stupid values
	if (bs.size_sample > bs.scr_w ||
		bs.size_sample > bs.scr_h)
		bs.size_sample = min(bs.scr_w, bs.scr_h);

	if (bs.size_sample != r_bloom_sample_size.value)
		Cvar_SetValue (&r_bloom_sample_size, bs.size_sample);

	data = Z_Malloc(bs.size_sample * bs.size_sample * 4);

	bs.tx_effect = GL_LoadTexture32("***bs.tx_effect***", bs.size_sample, bs.size_sample, (unsigned int*)data, IF_NOMIPMAP|IF_NOALPHA|IF_NOGAMMA);

	Z_Free (data);
}

/*
=================
R_Bloom_InitTextures
=================
*/
void R_Bloom_InitTextures(void)
{
	qbyte	*data;
	int		size;
	int maxtexsize;

	//find closer power of 2 to screen size
	for (bs.scr_w = 1;bs.scr_w < vid.pixelwidth;bs.scr_w *= 2);
	for (bs.scr_h = 1;bs.scr_h < vid.pixelheight;bs.scr_h *= 2);

	//disable blooms if we can't handle a texture of that size
	qglGetIntegerv(GL_MAX_TEXTURE_SIZE, &maxtexsize);
	if (bs.scr_w > maxtexsize ||
		bs.scr_h > maxtexsize)
	{
		bs.scr_w = bs.scr_h = 0;
		Cvar_SetValue (&r_bloom, 0);
		Con_Printf("WARNING: 'R_InitBloomScreenTexture' too high resolution for Light Bloom. Effect disabled\n");
		return;
	}

	//init the screen texture
	size = bs.scr_w * bs.scr_h * 4;
	data = Z_Malloc(size);
	memset(data, 255, size);
	if (!TEXVALID(bs.tx_screen))
		bs.tx_screen = GL_AllocNewTexture("***bloom screen***", bs.scr_w, bs.scr_h);
	GL_MTBind(0, GL_TEXTURE_2D, bs.tx_screen);
	qglTexImage2D (GL_TEXTURE_2D, 0, GL_RGB, bs.scr_w, bs.scr_h, 0, GL_RGBA, GL_UNSIGNED_BYTE, data);
	qglTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
	qglTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
	Z_Free (data);


	//validate bloom size and init the bloom effect texture
	R_Bloom_InitEffectTexture ();

	//if screensize is more than 2x the bloom effect texture, set up for stepped downsampling
	bs.tx_downsample = r_nulltex;
	bs.size_downsample = 0;
	if (vid.pixelwidth > (bs.size_sample * 2) && !r_bloom_fast_sample.value)
	{
		bs.size_downsample = (int)(bs.size_sample * 2);
		data = Z_Malloc(bs.size_downsample * bs.size_downsample * 4);
		bs.tx_downsample = GL_LoadTexture32("***bs.tx_downsample***", bs.size_downsample, bs.size_downsample, (unsigned int*)data, IF_NOMIPMAP|IF_NOALPHA|IF_NOGAMMA);
		Z_Free (data);
	}

	//Init the screen backup texture
	if (bs.size_downsample)
		R_Bloom_InitBackUpTexture(bs.size_downsample);
	else
		R_Bloom_InitBackUpTexture(bs.size_sample);
}

void R_BloomRegister(void)
{
	Cvar_Register (&r_bloom, "bloom");
	Cvar_Register (&r_bloom_alpha, "bloom");
	Cvar_Register (&r_bloom_diamond_size, "bloom");
	Cvar_Register (&r_bloom_intensity, "bloom");
	Cvar_Register (&r_bloom_darken, "bloom");
	Cvar_Register (&r_bloom_sample_size, "bloom");
	Cvar_Register (&r_bloom_fast_sample, "bloom");
}

/*
=================
R_InitBloomTextures
=================
*/
void R_InitBloomTextures(void)
{
	bs.size_sample = 0;
	if (!r_bloom.ival)
		return;

	bs.tx_screen = r_nulltex;	//this came from a vid_restart, where none of the textures are valid any more.
	R_Bloom_InitTextures ();
}


/*
=================
R_Bloom_DrawEffect
=================
*/
void R_Bloom_DrawEffect(void)
{
	GL_MTBind(0, GL_TEXTURE_2D, bs.tx_effect);
	qglEnable(GL_BLEND);
	qglBlendFunc(GL_ONE, GL_ONE);
	qglColor4f(r_bloom_alpha.value, r_bloom_alpha.value, r_bloom_alpha.value, 1.0f);
	GL_TexEnv(GL_MODULATE);
	qglBegin(GL_QUADS);
	qglTexCoord2f	(0,					bs.smp_t);
	qglVertex2f		(bs.vp_x,			bs.vp_y);
	qglTexCoord2f	(0,					0);
	qglVertex2f		(bs.vp_x,			bs.vp_y + bs.vp_h);
	qglTexCoord2f	(bs.smp_s,			0);
	qglVertex2f		(bs.vp_x + bs.vp_w,	bs.vp_y + bs.vp_h);
	qglTexCoord2f	(bs.smp_s,			bs.smp_t);
	qglVertex2f		(bs.vp_x + bs.vp_w,	bs.vp_y);
	qglEnd();

	qglDisable(GL_BLEND);
}


#if 0
/*
=================
R_Bloom_GeneratexCross - alternative bluring method
=================
*/
void R_Bloom_GeneratexCross(void)
{
	int			i;
	static int		BLOOM_BLUR_RADIUS = 8;
	//static float	BLOOM_BLUR_INTENSITY = 2.5f;
	float	BLOOM_BLUR_INTENSITY;
	static float intensity;
	static float range;

	//set up sample size workspace
	qglViewport( 0, 0, bs.smp_w, bs.smp_h );
	qglMatrixMode( GL_PROJECTION );
    qglLoadIdentity ();
	qglOrtho(0, bs.smp_w, bs.smp_h, 0, -10, 100);
	qglMatrixMode( GL_MODELVIEW );
    qglLoadIdentity ();

	//copy small scene into bs.tx_effect
	GL_Bind(0, bs.tx_effect);
	qglCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, bs.smp_w, bs.smp_h);

	//start modifying the small scene corner
	qglColor4f( 1.0f, 1.0f, 1.0f, 1.0f );
	qglEnable(GL_BLEND);

	//darkening passes
	if( r_bloom_darken.value )
	{
		qglBlendFunc(GL_DST_COLOR, GL_ZERO);
		GL_TexEnv(GL_MODULATE);

		for(i=0; i<r_bloom_darken->integer ;i++) {
			R_Bloom_SamplePass( 0, 0 );
		}
		qglCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, bs.smp_w, bs.smp_h);
	}

	//bluring passes
	if( BLOOM_BLUR_RADIUS ) {

		qglBlendFunc(GL_ONE, GL_ONE);

		range = (float)BLOOM_BLUR_RADIUS;

		BLOOM_BLUR_INTENSITY = r_bloom_intensity.value;
		//diagonal-cross draw 4 passes to add initial smooth
		qglColor4f( 0.5f, 0.5f, 0.5f, 1.0);
		R_Bloom_SamplePass( 1, 1 );
		R_Bloom_SamplePass( -1, 1 );
		R_Bloom_SamplePass( -1, -1 );
		R_Bloom_SamplePass( 1, -1 );
		qglCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, bs.smp_w, bs.smp_h);

		for(i=-(BLOOM_BLUR_RADIUS+1);i<BLOOM_BLUR_RADIUS;i++) {
			intensity = BLOOM_BLUR_INTENSITY/(range*2+1)*(1 - fabs(i*i)/(float)(range*range));
			if( intensity < 0.05f ) continue;
			qglColor4f( intensity, intensity, intensity, 1.0f);
			R_Bloom_SamplePass( i, 0 );
			//R_Bloom_SamplePass( -i, 0 );
		}

		qglCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, bs.smp_w, bs.smp_h);

		//for(i=0;i<BLOOM_BLUR_RADIUS;i++) {
		for(i=-(BLOOM_BLUR_RADIUS+1);i<BLOOM_BLUR_RADIUS;i++) {
			intensity = BLOOM_BLUR_INTENSITY/(range*2+1)*(1 - fabs(i*i)/(float)(range*range));
			if( intensity < 0.05f ) continue;
			qglColor4f( intensity, intensity, intensity, 1.0f);
			R_Bloom_SamplePass( 0, i );
			//R_Bloom_SamplePass( 0, -i );
		}

		qglCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, bs.smp_w, bs.smp_h);
	}

	//restore full screen workspace
	qglViewport( 0, 0, glState.width, glState.height );
	qglMatrixMode( GL_PROJECTION );
    qglLoadIdentity ();
	qglOrtho(0, glState.width, glState.height, 0, -10, 100);
	qglMatrixMode( GL_MODELVIEW );
    qglLoadIdentity ();
}
#endif


/*
=================
R_Bloom_GeneratexDiamonds
=================
*/
void R_Bloom_GeneratexDiamonds(void)
{
	int			i, j;
	float intensity;

	//set up sample size workspace
	qglViewport(0, 0, bs.smp_w, bs.smp_h);
	qglMatrixMode(GL_PROJECTION);
    qglLoadIdentity();
	qglOrtho(0, bs.smp_w, bs.smp_h, 0, -10, 100);
	qglMatrixMode(GL_MODELVIEW);
    qglLoadIdentity();

	//copy small scene into bs.tx_effect
	GL_MTBind(0, GL_TEXTURE_2D, bs.tx_effect);
	qglCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, bs.smp_w, bs.smp_h);

	//start modifying the small scene corner
	qglColor4f( 1.0f, 1.0f, 1.0f, 1.0f );
	qglEnable(GL_BLEND);

	//darkening passes
	if (r_bloom_darken.value)
	{
		qglBlendFunc(GL_DST_COLOR, GL_ZERO);
		GL_TexEnv(GL_MODULATE);

		for (i=0; i<r_bloom_darken.value ;i++)
		{
			R_Bloom_SamplePass(0, 0);
		}
		qglCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, bs.smp_w, bs.smp_h);
	}

	//bluring passes
	//qglBlendFunc(GL_ONE, GL_ONE);
	qglBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_COLOR);

	{
		int size = r_bloom_diamond_size.value;
		float rad = r_bloom_diamond_size.value / 2.0f;
		float point = (r_bloom_diamond_size.value - 1) / 2.0f;
		float mult = min(1.0f, r_bloom_intensity.value * 2.0f / rad);

		for (i=0; i<size; i++)
		{
			for (j=0; j<size; j++)
			{
				float f = ((point + 1.0f) - (fabs(point - i) + fabs(point - j))) / (point + 1.0f);
				//float f = 1.0f - (fabs(point - i) * fabs(point - j) / (point * point)); // circle/cross?
				intensity = mult * f;
				if (intensity < 0.005f)
					continue;
				qglColor4f(intensity, intensity, intensity, 1.0);
				R_Bloom_SamplePass( i-rad, j-rad );
			}
		}
	}

	qglCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, bs.smp_w, bs.smp_h);

	//restore full screen workspace
	qglViewport(0, 0, vid.pixelwidth, vid.pixelheight);
	qglMatrixMode(GL_PROJECTION);
    qglLoadIdentity ();
	qglOrtho(0, vid.pixelwidth, vid.pixelheight, 0, -10, 100);
	qglMatrixMode(GL_MODELVIEW);
    qglLoadIdentity ();
}

/*
=================
R_Bloom_DownsampleView
=================
*/
void R_Bloom_DownsampleView( void )
{
	qglDisable(GL_BLEND);
	qglColor4f(1.0f, 1.0f, 1.0f, 1.0f);

	//stepped downsample
	if (bs.size_downsample)
	{
		int		midsample_width = bs.size_downsample * bs.smp_s;
		int		midsample_height = bs.size_downsample * bs.smp_t;

		//copy the screen and draw resized
		GL_MTBind(0, GL_TEXTURE_2D, bs.tx_screen);
		qglCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, bs.vp_x, vid.pixelheight - (bs.vp_y + bs.vp_h), bs.vp_w, bs.vp_h);

		R_Bloom_Quad(0, vid.pixelheight-midsample_height, midsample_width, midsample_height, bs.scr_s, bs.scr_t);

		//now copy into Downsampling (mid-sized) texture
		GL_MTBind(0, GL_TEXTURE_2D, bs.tx_downsample);
		qglCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, midsample_width, midsample_height);

		//now draw again in bloom size
		qglColor4f(0.5f, 0.5f, 0.5f, 1.0f);
		R_Bloom_Quad(0,  vid.pixelheight-bs.smp_h, bs.smp_w, bs.smp_h, bs.smp_s, bs.smp_t);

		//now blend the big screen texture into the bloom generation space (hoping it adds some blur)
		qglEnable(GL_BLEND);
		qglBlendFunc(GL_ONE, GL_ONE);
		qglColor4f(0.5f, 0.5f, 0.5f, 1.0f);
		GL_MTBind(0, GL_TEXTURE_2D, bs.tx_screen);
		R_Bloom_Quad(0,  vid.pixelheight-bs.smp_h, bs.smp_w, bs.smp_h, bs.scr_s, bs.scr_t);
		qglColor4f(1.0f, 1.0f, 1.0f, 1.0f);
		qglDisable(GL_BLEND);
	}
	else
	{	//downsample simple
		GL_MTBind(0, GL_TEXTURE_2D, bs.tx_screen);
		qglCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, bs.vp_x, vid.pixelheight - (bs.vp_y + bs.vp_h), bs.vp_w, bs.vp_h);
		R_Bloom_Quad(0, vid.pixelheight-bs.smp_h, bs.smp_w, bs.smp_h, bs.scr_s, bs.scr_t);
	}
}

/*
=================
R_BloomBlend
=================
*/
void R_BloomBlend (void)
{
	int buw, buh;

	if (!bs.size_sample || bs.scr_w < vid.pixelwidth || bs.scr_h < vid.pixelheight)
		R_Bloom_InitTextures();

	if (bs.scr_w < bs.size_sample ||
		bs.scr_h < bs.size_sample)
		return;

	PPL_RevertToKnownState();
#ifdef warningmsg
#pragma warningmsg("Note: Bloom doesn't use the backend.")
#endif

	//set up full screen workspace
	qglViewport(0, 0, vid.pixelwidth, vid.pixelheight);
	qglDisable(GL_DEPTH_TEST);
	qglMatrixMode(GL_PROJECTION);
    qglLoadIdentity();
	qglOrtho(0, vid.pixelwidth, vid.pixelheight, 0, -10, 100);
	qglMatrixMode(GL_MODELVIEW);
    qglLoadIdentity();
	GL_CullFace(0);

	qglDisable(GL_BLEND);
	qglEnable(GL_TEXTURE_2D);

	qglColor4f(1, 1, 1, 1);

	//set up current sizes
	bs.vp_x = r_refdef.pxrect.x;
	bs.vp_y = vid.pixelheight - r_refdef.pxrect.y;
	bs.vp_w = r_refdef.pxrect.width;
	bs.vp_h = r_refdef.pxrect.height;
	bs.scr_s = (float)bs.vp_w / (float)bs.scr_w;
	bs.scr_t = (float)bs.vp_h / (float)bs.scr_h;
	if (bs.vp_h > bs.vp_w)
	{
		bs.smp_s = (float)bs.vp_w / (float)bs.vp_h;
		bs.smp_t = 1.0f;
	}
	else
	{
		bs.smp_s = 1.0f;
		bs.smp_t = (float)bs.vp_h / (float)bs.vp_w;
	}
	bs.smp_w = bs.size_sample * bs.smp_s;
	bs.smp_h = bs.size_sample * bs.smp_t;

	bs.smp_s = (float)bs.smp_w/bs.size_sample;
	bs.smp_t = (float)bs.smp_h/bs.size_sample;

	buw = bs.size_backup * bs.smp_s;
	buh = bs.size_backup * bs.smp_t;

	//copy the screen space we'll use to work into the backup texture
	GL_MTBind(0, GL_TEXTURE_2D, bs.tx_backup);
	qglCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, buw, buh);

	//create the bloom image
	R_Bloom_DownsampleView();

	R_Bloom_GeneratexDiamonds();
	//R_Bloom_GeneratexCross();

	//restore the screen-backup to the screen
	qglDisable(GL_BLEND);
	GL_MTBind(0, GL_TEXTURE_2D, bs.tx_backup);
	qglColor4f(1, 1, 1, 1);
	R_Bloom_Quad(0,
		vid.pixelheight - (buh),
		buw,
		buh,
		bs.smp_s,
		bs.smp_t);

	R_Bloom_DrawEffect();


	qglBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

	if (qglGetError())
		Con_Printf("GL Error whilst rendering bloom\n");

	PPL_RevertToKnownState();
}

#endif