#include "g_local.h"

//#define DISABLE_FOG

#ifdef DISABLE_FOG
void Fog_Init()
{
}
void Fog(vec3_t viewpoint)
{
}
void Fog_Off()
{
}
void SP_trigger_fog(edict_t *self)
{
	G_FreeEdict(self);
}
void SP_target_fog(edict_t *self)
{
	G_FreeEdict(self);
}
void Cmd_Fog_f(edict_t *ent)
{
}
#else

#include <windows.h>
#define __MSC__
#include <glide.h>
#include <gl/gl.h>

fog_t		gfogs[MAX_FOGS];

fog_t		trig_fade_fog;
fog_t		fade_fog;
fog_t		*pfog;

GrFog_t		fogtable[GR_FOG_TABLE_SIZE];
qboolean	fogtable_generated=false;

HMODULE		hGlide;
HMODULE		hOpenGL;

qboolean	InTriggerFog;
float		last_software_frame;
float		last_3dfx_frame;
float		last_opengl_frame;

int GLModels[3] = {GL_LINEAR, GL_EXP, GL_EXP2};

typedef void (__stdcall *GRBUFFERCLEAR) ( GrColor_t color, GrAlpha_t alpha, FxU16 depth );
typedef void (__stdcall *GRFOGCOLORVALUE) ( GrColor_t value );
typedef void (__stdcall *GRFOGMODE) ( GrFogMode_t mode );
typedef void (__stdcall *GRFOGTABLE) ( GrFog_t fogTable[GR_FOG_TABLE_SIZE] );
typedef void (__stdcall *GUFOGGENERATEEXP) ( GrFog_t fogTable[GR_FOG_TABLE_SIZE], float density );
typedef void (__stdcall *GUFOGGENERATEEXP2) ( GrFog_t fogTable[GR_FOG_TABLE_SIZE], float density );
typedef void (__stdcall *GUFOGGENERATELINEAR) ( GrFog_t fogTable[GR_FOG_TABLE_SIZE], float nearW, float farW );
GRBUFFERCLEAR Glide_grBufferClear;
GRFOGCOLORVALUE Glide_grFogColorValue;
GRFOGMODE Glide_grFogMode;
GRFOGTABLE Glide_grFogTable;
GUFOGGENERATEEXP Glide_guFogGenerateExp;
GUFOGGENERATEEXP2 Glide_guFogGenerateExp2;
GUFOGGENERATELINEAR Glide_guFogGenerateLinear;

typedef void (__stdcall *GRCHROMAKEYMODE) ( GrChromakeyMode_t mode );
typedef void (__stdcall *GRCHROMAKEYVALUE) ( GrColor_t value );
GRCHROMAKEYMODE Glide_grChromakeyMode;
GRCHROMAKEYVALUE Glide_grChromakeyValue;

//typedef void (__stdcall *GRCOLORCOMBINE) ( GrCombineFunction_t function, GrCombineFactor_t factor,
//               GrCombineLocal_t local, GrCombineOther_t other,
//               FxBool invert );
//typedef void (__stdcall *GRCONSTANTCOLORVALUE) ( GrColor_t value );
//typedef void (__stdcall *GRDRAWPOINT) ( const GrVertex *pt );
//GRCOLORCOMBINE Glide_grColorCombine;
//GRCONSTANTCOLORVALUE Glide_grConstantColorValue;
//GRDRAWPOINT Glide_grDrawPoint;


typedef void (WINAPI *GLCLEARCOLOR) (GLclampf red, GLclampf green, GLclampf blue, GLclampf alpha);
typedef void (WINAPI *GLDISABLE) (GLenum cap);
typedef void (WINAPI *GLENABLE) (GLenum cap);
typedef void (WINAPI *GLFOGF) (GLenum pname, GLfloat param);
typedef void (WINAPI *GLFOGFV) (GLenum pname, const GLfloat *params);
typedef void (WINAPI *GLFOGI) (GLenum pname, GLint param);
typedef void (WINAPI *GLHINT) (GLenum target, GLenum mode);
GLCLEARCOLOR GL_glClearColor;
GLDISABLE GL_glDisable;
GLENABLE GL_glEnable;
GLFOGF GL_glFogf;
GLFOGFV GL_glFogfv;
GLFOGI GL_glFogi;
GLHINT GL_glHint;

#define FOG_ON       1
#define FOG_TOGGLE   2
#define FOG_TURNOFF  4
#define FOG_STARTOFF 8

#define COLOR(r,g,b) ((((BYTE)(b)|((WORD)((BYTE)(g))<<8))|(((DWORD)(BYTE)(r))<<16)))

void GlideFogTable();
void fog_fade (edict_t *self);

void Fog_Off()
{
	if(deathmatch->value || coop->value)
		return;

	if(gl_driver && vid_ref)
	{
		if(!strcmp(vid_ref->string,"gl"))
		{
			if(!Q_stricmp(gl_driver->string,"3dfxgl")) {
				if(hGlide) Glide_grFogMode(GR_FOG_DISABLE);
			} else {
				if(hOpenGL) GL_glDisable (GL_FOG);
			}
		}
		else
		{
			edict_t	*player;

			player = &g_edicts[1];
			player->client->fadein = 0;
		}
	}
}

void Fog_ConsoleFog()
{
	// This routine is ONLY called for console fog commands

	if(deathmatch->value || coop->value)
		return;

	if(!level.active_fog) return;

	memcpy(&level.fog,&gfogs[0],sizeof(fog_t));
	pfog = &level.fog;

	// Force sensible values for linear:
	if(pfog->Model==0 && pfog->Near==0. && pfog->Far==0.)
	{
		pfog->Near=64;
		pfog->Far=1024;
	}
	GlideFogTable();
}

void Cmd_Say_f (edict_t *ent, qboolean team, qboolean arg0);
void Cmd_Fog_f(edict_t *ent)
{
	char	*cmd;
	char	*parm;
	fog_t	*fog;

	fog = &gfogs[0];
	cmd = gi.argv(0);
	if(gi.argc() < 2)
		parm = NULL;
	else
		parm = gi.argv(1);

	if (Q_stricmp (cmd, "fog_help") == 0 )
	{
		gi.dprintf("Fog parameters for console only.\n"
			       "Use fog_active to see parameters for currently active fog.\n");

		gi.dprintf("\nUse \"fog [0/1]\" to turn fog off/on (currently %s)\n"
			"Current GL driver is %s\n",(level.active_fog > 0 ? "on" : "off"), gl_driver->string);

		gi.dprintf("Fog_Red     = red component   (0-1)\n"
				   "Fog_Grn     = green component (0-1)\n"
				   "Fog_Blu     = blue component  (0-1)\n"
				   "Fog_Model     0=linear, 1=exponential, 2=exponential squared\n\n"
				   "Linear parameters:\n"
				   "Fog_Near    = fog start distance (>0 and < Fog_Far)\n"
				   "Fog_Far     = distance where objects are completely obscured\n"
				   "              (<5000 and > Fog_Near)\n"
				   "Exponential parameters:\n"
				   "Fog_Density   Best results with values < 100\n\n"
				   "Command without a value will show current setting\n");
	}
	else if(Q_stricmp (cmd, "fog_active") == 0 )
	{
		if(level.active_fog)
		{
			gi.dprintf("Active fog:\n"
				"  Color: %f, %f, %f\n"
				"  Model: %s\n",
				level.fog.Color[0],level.fog.Color[1],level.fog.Color[2],
				(level.fog.Model==1 ? "Exp" : (level.fog.Model==2 ? "Exp2" : "Linear")));
			if(level.fog.Model)
				gi.dprintf("Density: %f\n",level.fog.Density);
			else
			{
				gi.dprintf("   Near: %f\n",level.fog.Near);
				gi.dprintf("    Far: %f\n",level.fog.Far);
			}
		}
		else
			gi.dprintf("No fogs currently active\n");
	}
	else if(Q_stricmp (cmd, "fog_stuff") == 0 )
	{
		gi.dprintf("active_fog=%d, last_active_fog=%d\n",level.active_fog,level.last_active_fog);
	}
	else if(Q_stricmp (cmd, "fog") == 0 )
	{
		if(parm)
		{
			int on;
			on = atoi(parm);
			level.active_fog = level.active_target_fog = (on ? 1 : 0);
			Fog_ConsoleFog();
		}
		gi.dprintf("fog is %s\n",(level.active_fog ? "on" : "off"));
	}
	else if(Q_stricmp (cmd, "Fog_Red") == 0 )
	{
		if(!parm)
			gi.dprintf("%s = %f\n",cmd,fog->Color[0]);
		else
		{
			level.active_fog = level.active_target_fog = 1;
			fog->Color[0] = max(0.0f,min(1.0f,(float)atof(parm)));
			fog->GlideColor[0] = (int)(255 * fog->Color[0]);
			Fog_ConsoleFog();
		}
	}
	else if(Q_stricmp (cmd, "Fog_Grn") == 0 )
	{
		if(!parm)
			gi.dprintf("%s = %f\n",cmd,fog->Color[1]);
		else
		{
			level.active_fog = level.active_target_fog = 1;
			fog->Color[1] = max(0.0f,min(1.0f,(float)atof(parm)));
			fog->GlideColor[1] = (int)(255 * fog->Color[1]);
			Fog_ConsoleFog();
		}
	}
	else if(Q_stricmp (cmd, "Fog_Blu") == 0 )
	{
		if(!parm)
			gi.dprintf("%s = %f\n",cmd,fog->Color[2]);
		else
		{
			level.active_fog = level.active_target_fog = 1;
			fog->Color[2] = max(0.0f,min(1.0f,(float)atof(parm)));
			fog->GlideColor[2] = (int)(255 * fog->Color[2]);
			Fog_ConsoleFog();
		}
	}
	else if(Q_stricmp (cmd, "Fog_Near") == 0 )
	{
		if(!parm)
			gi.dprintf("%s = %f\n",cmd,fog->Near);
		else
		{
			level.active_fog = level.active_target_fog = 1;
			fog->Near = (float)atof(parm);
			Fog_ConsoleFog();
		}
	}
	else if(Q_stricmp (cmd, "Fog_Far") == 0 )
	{
		if(!parm)
			gi.dprintf("%s = %f\n",cmd,fog->Far);
		else
		{
			level.active_fog = level.active_target_fog = 1;
			fog->Far = (float)atof(parm);
			Fog_ConsoleFog();
		}
	}
	else if(Q_stricmp (cmd, "Fog_Model") == 0 )
	{
		if(!parm)
			gi.dprintf("%s = %d\n0=Linear\n1=Exp\n2=Exp2\n",cmd,fog->Model);
		else
		{
			level.active_fog = level.active_target_fog = 1;
//			fog->Model = max(0,min(2,atoi(parm)));
			fog->Model = max(0,min(3,atoi(parm)));
			if(fog->Model == 3)
				fog->GL_Model = GLModels[2];
			else
				fog->GL_Model = GLModels[fog->Model];
			Fog_ConsoleFog();
		}
	}
	else if(Q_stricmp (cmd, "Fog_Density") == 0 )
	{
		if(!parm)
			gi.dprintf("%s = %f\n",cmd,fog->Density);
		else
		{
			level.active_fog = level.active_target_fog = 1;
			fog->Density = fog->Density1 = fog->Density2 = (float)atof(parm);
			Fog_ConsoleFog();
		}
	}
	else if(Q_stricmp (cmd, "Fog_List") == 0 )
	{
		int	i;

		gi.dprintf("level.fogs=%d\n",level.fogs);
		gi.dprintf("level.trigger_fogs=%d\n",level.trigger_fogs);
		for(i=0; i<level.fogs; i++)
		{
			pfog = &gfogs[i];
			gi.dprintf("Fog #%d\n",i+1);
			gi.dprintf("Trigger=%s\n",(pfog->Trigger ? "true" : "false"));
			gi.dprintf("Model=%d, Near=%g, Far=%g, Density=%g\n",
				pfog->Model, pfog->Near, pfog->Far, pfog->Density);
			gi.dprintf("Color=%g,%g,%g\n",pfog->Color[0],pfog->Color[1],pfog->Color[2]);
			gi.dprintf("Targetname=%s\n",(pfog->ent ? pfog->ent->targetname : "no ent"));
		}
	}
	else
		Cmd_Say_f (ent, false, true);
}

/*
void SoftwareFog()
{
	edict_t	*player = &g_edicts[1];

	player->client->fadein       = level.framenum - 1;
	player->client->fadehold     = level.framenum + 2;
	player->client->fadeout      = 0;
	player->client->fadecolor[0] = pfog->Color[0];
	player->client->fadecolor[1] = pfog->Color[1];
	player->client->fadecolor[2] = pfog->Color[2];

	if(pfog->Model == 0)
		player->client->fadealpha = pfog->Far/256.;
	else if(pfog->Model == 1)
		player->client->fadealpha = pfog->Density/30;
	else
		player->client->fadealpha = pfog->Density/15;

	if(player->client->fadealpha > 0.9)
		player->client->fadealpha = 0.9;

	last_software_frame = level.framenum;

}
*/

void GlideFogTable()
{
	int		i;
	float	density;
	float	w, dw4;

	if(!hGlide) return;
	if(strcmp(gl_driver->string,"3dfxgl") || strcmp(vid_ref->string,"gl") ) return;
	if(last_software_frame + 10 > level.framenum) return;
	if(last_opengl_frame   + 10 > level.framenum) return;

	switch(pfog->Model)
	{
	case 1:
		Glide_guFogGenerateExp( fogtable, pfog->Density/10000.f );
		break;
	case 2:
		Glide_guFogGenerateExp2( fogtable, pfog->Density/10000.f );
		break;
	case 3:
		// Home-grown EXP4 model
		density = pfog->Density/10000.f;
		for(i=0; i<GR_FOG_TABLE_SIZE-1; i++)
		{
			w = pow(2.0,(float)i/4.0);
			dw4 = pow(density*w,4);
			fogtable[i] = (GrFog_t)(255. * (1.0 - exp(-dw4)));
		}
		fogtable[GR_FOG_TABLE_SIZE] = 255;
		break;
	default:
		Glide_guFogGenerateLinear( fogtable, pfog->Near, pfog->Far);
	}
	fogtable_generated=true;
}

void GlideFog()
{
	GrColor_t color;

	if(!hGlide)	return;
	if(last_software_frame + 10 > level.framenum) return;
	if(last_opengl_frame   + 10 > level.framenum) return;
	if(!fogtable_generated) GlideFogTable();

//	gi.dprintf("Name=%s, Model=%d, Near=%g, Far=%g, Density=%g, Color=%g,%g,%g\n",
//			pfog->ent->targetname, pfog->Model,pfog->Near, pfog->Far, pfog->Density,
//			pfog->GlideColor[0],pfog->GlideColor[1],pfog->GlideColor[2]);
	
	Glide_grFogTable( fogtable );
	color = COLOR(pfog->GlideColor[0],pfog->GlideColor[1],pfog->GlideColor[2]);
	Glide_grBufferClear( color, (FxU8)0, (FxU16)0);
	Glide_grFogColorValue( color );
	Glide_grFogMode( GR_FOG_WITH_TABLE );

	last_3dfx_frame = level.framenum;
}

void GLFog()
{
	GLfloat fogColor[4];
	if(!hOpenGL) return;
	fogColor[0] = pfog->Color[0];
	fogColor[1] = pfog->Color[1];
	fogColor[2] = pfog->Color[2];
	fogColor[3] = 1.0;
	GL_glEnable (GL_FOG);                               // turn on fog, otherwise you won't see any
	GL_glClearColor ( fogColor[0], fogColor[1], fogColor[2], fogColor[3]); // Clear the background color to the fog color
	GL_glFogi (GL_FOG_MODE, pfog->GL_Model);
	GL_glFogfv (GL_FOG_COLOR, fogColor);
	if(pfog->GL_Model == GL_LINEAR)
	{
		GL_glFogf (GL_FOG_START, pfog->Near);
		GL_glFogf (GL_FOG_END, pfog->Far);
	}
	else
		GL_glFogf (GL_FOG_DENSITY, pfog->Density/10000.f);
    GL_glHint (GL_FOG_HINT, GL_NICEST);

	last_opengl_frame = level.framenum;
}

void trig_fog_fade (edict_t *self)
{
	float	frames;
	int		index;

	if(!InTriggerFog)
	{
		self->nextthink = 0;
		return;
	}
	if(level.framenum <= self->goal_frame)
	{
		index = self->fog_index-1;
		frames = self->goal_frame - level.framenum + 1;
		if(trig_fade_fog.Model == 0)
		{
			trig_fade_fog.Near += (gfogs[index].Near - trig_fade_fog.Near)/frames;
			trig_fade_fog.Far  += (gfogs[index].Far  - trig_fade_fog.Far )/frames;
		}
		else
		{
			trig_fade_fog.Density  += (gfogs[index].Density  - trig_fade_fog.Density) /frames;
			trig_fade_fog.Density1 += (gfogs[index].Density1 - trig_fade_fog.Density1)/frames;
			trig_fade_fog.Density2 += (gfogs[index].Density2 - trig_fade_fog.Density2)/frames;
		}
		trig_fade_fog.Color[0] += (gfogs[index].Color[0] - trig_fade_fog.Color[0])/frames;
		trig_fade_fog.Color[1] += (gfogs[index].Color[1] - trig_fade_fog.Color[1])/frames;
		trig_fade_fog.Color[2] += (gfogs[index].Color[2] - trig_fade_fog.Color[2])/frames;
		VectorScale(trig_fade_fog.Color,255,trig_fade_fog.GlideColor);
		trig_fade_fog.GL_Model = GLModels[trig_fade_fog.Model];
		self->nextthink = level.time + FRAMETIME;
		fogtable_generated = false;
		gi.linkentity(self);
	}
}

void init_trigger_fog_delay (edict_t *self)
{
	int		i;
	int		index;
	edict_t *e;

	index = self->fog_index-1;

	// scan for other trigger_fog's that are currently "thinking", iow
	// the trigger_fog has a delay and is ramping. If found, stop the ramp for those fogs
	for(i=1, e=g_edicts+i; i<globals.num_edicts; i++, e++)
	{
		if(!e->inuse) continue;
		if(e == self) continue;
		if(e->think == trig_fog_fade || e->think == fog_fade)
		{
			e->think = NULL;
			e->nextthink = 0;
			gi.linkentity(e);
		}
	}

	self->spawnflags |= FOG_ON;
	if(!level.active_fog)
	{
		// Fog isn't currently on
		memcpy(&level.fog,&gfogs[index],sizeof(fog_t));
		level.fog.Near     = 4999.;
		level.fog.Far      = 5000.;
		level.fog.Density  = 0.0;
		level.fog.Density1 = 0.0;
		level.fog.Density2 = 0.0;
	}
	VectorCopy(self->fog_color,gfogs[index].Color);
	VectorScale(self->fog_color,255,gfogs[index].GlideColor);
	gfogs[index].Near      = self->fog_near;
	gfogs[index].Far       = self->fog_far;
	gfogs[index].Density   = self->fog_density;
	gfogs[index].Density1  = self->fog_density;
	gfogs[index].Density2  = self->density;
	self->goal_frame = level.framenum + self->delay*10 + 1;
	self->think      = trig_fog_fade;
	self->nextthink  = level.time + FRAMETIME;
	memcpy(&trig_fade_fog,&level.fog,sizeof(fog_t));
	level.active_fog = self->fog_index;
}

void Fog(vec3_t viewpoint)
{
	edict_t	*triggerfog;
	edict_t	*player = &g_edicts[1];

	if(!gl_driver || !vid_ref)
		return;

	if(deathmatch->value || coop->value)
		return;

	if(stricmp(vid_ref->string,"gl"))
	{
		last_software_frame = level.framenum;
		level.active_fog = 0;
		return;
	}

	InTriggerFog = false;
	if(level.trigger_fogs)
	{
		int i;
		int trigger;
		trigger=0;
		for(i=1; i<level.fogs; i++)
		{
			if(!gfogs[i].Trigger) continue;
			if(!gfogs[i].ent->inuse) continue;
			if(!(gfogs[i].ent->spawnflags & FOG_ON)) continue;
			if(viewpoint[0] < gfogs[i].ent->absmin[0]) continue;
			if(viewpoint[0] > gfogs[i].ent->absmax[0]) continue;
			if(viewpoint[1] < gfogs[i].ent->absmin[1]) continue;
			if(viewpoint[1] > gfogs[i].ent->absmax[1]) continue;
			if(viewpoint[2] < gfogs[i].ent->absmin[2]) continue;
			if(viewpoint[2] > gfogs[i].ent->absmax[2]) continue;
			trigger = i;
			break;
		}
		if(trigger)
		{
			InTriggerFog = true;
			triggerfog = gfogs[trigger].ent;

			if(level.last_active_fog != trigger+1)
			{
				if(triggerfog->delay)
					init_trigger_fog_delay(triggerfog);
				else
					memcpy(&level.fog,&gfogs[trigger],sizeof(fog_t));
				level.active_fog = trigger+1;
			}
			else if(triggerfog->delay)
				memcpy(&level.fog,&trig_fade_fog,sizeof(fog_t));
		}
		else
		{
			InTriggerFog = false;
			level.active_fog = level.active_target_fog;
			// if we are just coming out of a trigger_fog, force
			// level.fog to last active target_fog values
			if(level.active_fog && level.last_active_fog && gfogs[level.last_active_fog-1].Trigger)
			{
				edict_t	*ent = gfogs[level.active_fog-1].ent;
				if(ent && (ent->think == fog_fade))
					ent->think(ent);
				else
					memcpy(&level.fog,&gfogs[level.active_fog-1],sizeof(fog_t));
			}
		}
	}
	
	if(!level.active_fog) {
		if(level.last_active_fog)
			Fog_Off();
		level.last_active_fog = 0;
		return;
	}
	
	pfog = &level.fog;
	if(level.last_active_fog != level.active_fog)
		fogtable_generated = false;
	if((pfog->Density1 != pfog->Density2) && (game.maxclients == 1) && (pfog->Model))
	{
		float	density;
		float	dp;
		vec3_t	vp;

		AngleVectors(player->client->ps.viewangles,vp,0,0);
		dp = DotProduct(pfog->Dir,vp) + 1.0;
		density = ((pfog->Density1*dp) + (pfog->Density2*(2.0-dp)))/2.;
		if(pfog->Density != density)
		{
			pfog->Density = density;
			fogtable_generated = false;
		}
	}
//	if(!fogtable_generated)
	{
		if(!strcmp(gl_driver->string,"3dfxgl"))
			GlideFog();
		else
			GLFog();
	}
	level.last_active_fog = level.active_fog;
}

void Fog_Init()
{
	char	GL_Lib[64];

	hGlide = LoadLibrary("glide2x.dll");
	if(hGlide)
	{
		Glide_grBufferClear       = (GRBUFFERCLEAR)GetProcAddress(hGlide,"_grBufferClear@12");
		Glide_grFogColorValue     = (GRFOGCOLORVALUE)GetProcAddress(hGlide,"_grFogColorValue@4");
		Glide_grFogMode           = (GRFOGMODE)GetProcAddress(hGlide,"_grFogMode@4");
		Glide_grFogTable          = (GRFOGTABLE)GetProcAddress(hGlide,"_grFogTable@4");
		Glide_guFogGenerateExp    = (GUFOGGENERATEEXP)GetProcAddress(hGlide,"_guFogGenerateExp@8");
		Glide_guFogGenerateExp2   = (GUFOGGENERATEEXP2)GetProcAddress(hGlide,"_guFogGenerateExp2@8");
		Glide_guFogGenerateLinear = (GUFOGGENERATELINEAR)GetProcAddress(hGlide,"_guFogGenerateLinear@12");

		Glide_grChromakeyMode     = (GRCHROMAKEYMODE)GetProcAddress(hGlide,"_grChromakeyMode@4");
		Glide_grChromakeyValue    = (GRCHROMAKEYVALUE)GetProcAddress(hGlide,"_grChromakeyValue@4");

//		Glide_grColorCombine      = (GRCOLORCOMBINE)GetProcAddress(hGlide,"_grColorCombine@20");
//		Glide_grConstantColorValue= (GRCONSTANTCOLORVALUE)GetProcAddress(hGlide,"_grConstantColorValue@4");
//		Glide_grDrawPoint         = (GRDRAWPOINT)GetProcAddress(hGlide,"_grDrawPoint@4");
	}

	if(gl_driver_fog && strlen(gl_driver_fog->string))
		strcpy(GL_Lib,gl_driver_fog->string);
	else
		strcpy(GL_Lib,"opengl32");
	strcat(GL_Lib,".dll");
	hOpenGL = LoadLibrary(GL_Lib);
	if(hOpenGL)
	{
		GL_glClearColor = (GLCLEARCOLOR)GetProcAddress(hOpenGL,"glClearColor");
		GL_glDisable    = (GLDISABLE)GetProcAddress(hOpenGL,"glDisable");
		GL_glEnable     = (GLENABLE)GetProcAddress(hOpenGL,"glEnable");
		GL_glFogf       = (GLFOGF)GetProcAddress(hOpenGL,"glFogf");
		GL_glFogfv      = (GLFOGFV)GetProcAddress(hOpenGL,"glFogfv");
		GL_glFogi       = (GLFOGI)GetProcAddress(hOpenGL,"glFogi");
		GL_glHint       = (GLHINT)GetProcAddress(hOpenGL,"glHint");
	}

	gfogs[0].Color[0] = gfogs[0].Color[1] = gfogs[0].Color[2] = 0.5;
	gfogs[0].GlideColor[0] = gfogs[0].GlideColor[1] = gfogs[0].GlideColor[2] = 127.;
	gfogs[0].Model    = 1;
	gfogs[0].GL_Model = GLModels[1];
	gfogs[0].Density  = 20.;
	gfogs[0].Trigger  = false;
}


void fog_fade (edict_t *self)
{
	float	frames;
	int		index;

	if(level.framenum <= self->goal_frame)
	{
		index = self->fog_index-1;
		frames = self->goal_frame - level.framenum + 1;
		if(fade_fog.Model == 0)
		{
			fade_fog.Near += (gfogs[index].Near - fade_fog.Near)/frames;
			fade_fog.Far  += (gfogs[index].Far  - fade_fog.Far )/frames;
		}
		else
		{
			fade_fog.Density  += (gfogs[index].Density  - fade_fog.Density) /frames;
			fade_fog.Density1 += (gfogs[index].Density1 - fade_fog.Density1)/frames;
			fade_fog.Density2 += (gfogs[index].Density2 - fade_fog.Density2)/frames;
		}
		fade_fog.Color[0] += (gfogs[index].Color[0] - fade_fog.Color[0])/frames;
		fade_fog.Color[1] += (gfogs[index].Color[1] - fade_fog.Color[1])/frames;
		fade_fog.Color[2] += (gfogs[index].Color[2] - fade_fog.Color[2])/frames;
		VectorScale(fade_fog.Color,255,fade_fog.GlideColor);
		fade_fog.GL_Model = GLModels[fade_fog.Model];
		self->nextthink = level.time + FRAMETIME;
		if(!InTriggerFog)
			memcpy(&level.fog,&fade_fog,sizeof(fog_t));
		fogtable_generated = false;
		gi.linkentity(self);
	}
	else
	{
//		if(!(self->spawnflags & FOG_ON))
		if(self->spawnflags & FOG_TURNOFF)
			level.active_fog = level.active_target_fog = 0;
	}
}

void target_fog_use (edict_t *self, edict_t *other, edict_t *activator)
{
	int		i;
	int		index;
	edict_t *e;

	self->count--;
	if(!self->count) {
		self->think = G_FreeEdict;
		self->nextthink = level.time + self->delay + 1;
	}

	if((self->spawnflags & FOG_ON) && (self->spawnflags & FOG_TOGGLE))
	{
		self->spawnflags &= ~FOG_ON;
		return;
	}
	else
		self->spawnflags |= FOG_ON;

	index = self->fog_index-1;

	InTriggerFog = false;

	// scan for other target_fog's that are currently "thinking", iow
	// the target_fog has a delay and is ramping. If found, stop the ramp for those fogs
	for(i=1, e=g_edicts+i; i<globals.num_edicts; i++, e++)
	{
		if(!e->inuse) continue;
		if(e->think == fog_fade)
		{
			e->nextthink = 0;
			gi.linkentity(e);
		}
	}

	if(self->spawnflags & FOG_TURNOFF)
	{
		// Fog is "turn off" only

		if( self->delay && level.active_fog )
		{
			gfogs[index].Far       = 5000.0;
			gfogs[index].Near      = 4999.0;
			gfogs[index].Density   = 0.0;
			gfogs[index].Density1  = 0.0;
			gfogs[index].Density2  = 0.0;
			VectorCopy(level.fog.Color,gfogs[index].Color);
			VectorScale(level.fog.Color,255,gfogs[index].GlideColor);
			self->goal_frame  = level.framenum + self->delay*10 + 1;
			self->think       = fog_fade;
			self->nextthink   = level.time + FRAMETIME;
			level.active_fog = level.active_target_fog = self->fog_index;
			memcpy(&fade_fog,&level.fog,sizeof(fog_t));
		}
		else
			level.active_fog = level.active_target_fog = 0;
	}
	else
	{
		if(self->delay)
		{
			if(!level.active_fog)
			{
				// Fog isn't currently on
				memcpy(&level.fog,&gfogs[index],sizeof(fog_t));
				level.fog.Near     = 4999.;
				level.fog.Far      = 5000.;
				level.fog.Density  = 0.0;
				level.fog.Density1 = 0.0;
				level.fog.Density2 = 0.0;
			}
			VectorCopy(self->fog_color,gfogs[index].Color);
			VectorScale(self->fog_color,255,gfogs[index].GlideColor);
			gfogs[index].Near      = self->fog_near;
			gfogs[index].Far       = self->fog_far;
			gfogs[index].Density   = self->fog_density;
			gfogs[index].Density1  = self->fog_density;
			gfogs[index].Density2  = self->density;
			self->goal_frame = level.framenum + self->delay*10 + 1;
			self->think      = fog_fade;
			self->nextthink  = level.time + FRAMETIME;
			memcpy(&fade_fog,&level.fog,sizeof(fog_t));
		} else {
			memcpy(&level.fog,&gfogs[index],sizeof(fog_t));
		}
		level.active_fog = level.active_target_fog = self->fog_index;
	}
}

void SP_target_fog (edict_t *self)
{
	fog_t *fog;

	if( !allow_fog->value )
	{
		G_FreeEdict(self);
		return;
	}
	if(deathmatch->value || coop->value)
	{
		G_FreeEdict(self);
		return;
	}

	if(!level.fogs) level.fogs = 1;   // 1st fog reserved for console commands

	if(level.fogs >= MAX_FOGS)
	{
		gi.dprintf("Maximum number of fogs exceeded!\n");
		G_FreeEdict(self);
		return;
	}

	if( self->delay < 0.)
		self->delay = 0.;

	self->fog_index = level.fogs+1;
	fog = &gfogs[level.fogs];
	fog->Trigger = false;
	fog->Model   = self->fog_model;
	if(fog->Model < 0 || fog->Model > 2) fog->Model = 0;
	fog->GL_Model = GLModels[fog->Model];
	VectorCopy(self->fog_color,fog->Color);
	VectorScale(self->fog_color,255,fog->GlideColor);
	if(self->spawnflags & FOG_TURNOFF) {
		fog->Near     = 4999;
		fog->Far      = 5000;
		fog->Density  = 0;
		fog->Density1 = 0;
		fog->Density2 = 0;
	} else {
		fog->Near     = self->fog_near;
		fog->Far      = self->fog_far;
		fog->Density  = self->fog_density;
		fog->Density1 = self->fog_density;
		if(self->density == 0.)
			self->density = self->fog_density;
		else if(self->density < 0.)
			self->density = 0.;
		fog->Density2= self->density;
	}
	AngleVectors(self->s.angles,fog->Dir,0,0);
	fog->ent = self;
	level.fogs++;
	self->use = target_fog_use;
	gi.linkentity(self);

	if(self->spawnflags & FOG_ON)
	{
		self->spawnflags &= ~FOG_ON;
		target_fog_use(self,NULL,NULL);
	}
}

void trigger_fog_use (edict_t *self, edict_t *other, edict_t *activator)
{
	if((self->spawnflags & FOG_ON) && (self->spawnflags & FOG_TOGGLE))
	{
		self->spawnflags &= ~FOG_ON;
		self->count--;
		if(!self->count)
		{
			self->think = G_FreeEdict;
			self->nextthink = level.time + FRAMETIME;
		}
	}
	else
	{
		self->spawnflags |= FOG_ON;
	}
}

void SP_trigger_fog (edict_t *self)
{
	fog_t *fog;

	if( !allow_fog->value )
	{
		G_FreeEdict(self);
		return;
	}
	if(deathmatch->value || coop->value)
	{
		G_FreeEdict(self);
		return;
	}
	if(!level.fogs) level.fogs = 1;   // 1st fog reserved for console commands

	if(level.fogs >= MAX_FOGS)
	{
		gi.dprintf("Maximum number of fogs exceeded!\n");
		G_FreeEdict(self);
		return;
	}

	self->fog_index = level.fogs+1;
	fog = &gfogs[level.fogs];
	fog->Trigger = true;
	fog->Model   = self->fog_model;
	if(fog->Model < 0 || fog->Model > 2) fog->Model = 0;
	fog->GL_Model = GLModels[fog->Model];
	VectorCopy(self->fog_color,fog->Color);
	VectorScale(self->fog_color,255,fog->GlideColor);
	if(self->spawnflags & FOG_TURNOFF) {
		fog->Near    = 4999;
		fog->Far     = 5000;
		fog->Density = 0;
		fog->Density1 = 0;
		fog->Density2 = 0;
	} else {
		fog->Near    = self->fog_near;
		fog->Far     = self->fog_far;
		fog->Density = self->fog_density;
		fog->Density1 = self->fog_density;
		if(self->density == 0.)
			self->density = self->fog_density;
		else if(self->density < 0.)
			self->density = 0.;
		fog->Density2= self->density;
	}
	if(!(self->spawnflags & FOG_STARTOFF))
		self->spawnflags |= FOG_ON;

	AngleVectors(self->s.angles,fog->Dir,0,0);
	VectorClear(self->s.angles);
	fog->ent     = self;
	level.fogs++;
	level.trigger_fogs++;
	self->movetype = MOVETYPE_NONE;
	self->svflags |= SVF_NOCLIENT;
	self->solid = SOLID_NOT;
	gi.setmodel (self, self->model);
	gi.linkentity(self);
}
#endif

/*
void SetChromakey()
{
	if(!gl_driver || !vid_ref)
		return;

	if(stricmp(vid_ref->string,"gl"))
		return;

	if(!strcmp(gl_driver->string,"3dfxgl"))
	{
		Glide_grChromakeyMode(GR_CHROMAKEY_ENABLE);
		Glide_grChromakeyValue(0xFF);
	}
	else
	{
	}
}
*/