/*
	gl_rmain.c

	(description)

	Copyright (C) 1996-1997  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:

		Free Software Foundation, Inc.
		59 Temple Place - Suite 330
		Boston, MA  02111-1307, USA

	$Id$
*/

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#ifdef HAVE_STRING_H
# include <string.h>
#endif
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif

#include <math.h>
#include <stdio.h>
#include <stdlib.h>

#include "QF/console.h"
#include "QF/cvar.h"
#include "QF/locs.h"
#include "QF/mathlib.h"
#include "QF/qargs.h"
#include "QF/render.h"
#include "QF/skin.h"
#include "QF/sound.h"
#include "QF/sys.h"
#include "QF/vid.h"
#include "QF/GL/defines.h"
#include "QF/GL/funcs.h"
#include "QF/GL/qf_rlight.h"
#include "QF/GL/qf_rsurf.h"
#include "QF/GL/qf_screen.h"
#include "QF/GL/qf_vid.h"

#include "compat.h"
#include "r_cvar.h"
#include "r_dynamic.h"
#include "r_local.h"
#include "view.h"

typedef struct {
	vec3_t      vert;
	float       lightdot;
} blended_vert_t;

typedef struct {
	blended_vert_t *verts;
	int        *order;
} vert_order_t;

entity_t    r_worldentity;

qboolean    r_cache_thrash;				// compatability

vec3_t      modelorg, r_entorigin;
entity_t   *currententity;

int         r_visframecount;			// bumped when going to a new PVS
int         r_framecount;				// used for dlight push checking

int         c_brush_polys, c_alias_polys;

qboolean    envmap;						// true during envmap command capture

int         mirrortexturenum;			// quake texturenum, not gltexturenum
qboolean    mirror;
mplane_t   *mirror_plane;

// view origin
vec3_t      vup;
vec3_t      vpn;
vec3_t      vright;
vec3_t      r_origin;

float       r_world_matrix[16];
float       r_base_world_matrix[16];

// screen size info
refdef_t    r_refdef;

mleaf_t    *r_viewleaf, *r_oldviewleaf;

int         d_lightstylevalue[256];		// 8.8 fraction of base light value

vec3_t		shadecolor;					// Ender (Extend) Colormod
float		modelalpha;					// Ender (Extend) Alpha

void        R_MarkLeaves (void);

//qboolean R_CullBlocked (vec3_t mins, vec3_t maxs, vec3_t org);


void
glrmain_init (void)
{
	// LordHavoc: place for gl_rmain setup code
}

inline void
R_RotateForEntity (entity_t *e)
{
	qfglTranslatef (e->origin[0], e->origin[1], e->origin[2]);

	qfglRotatef (e->angles[1], 0, 0, 1);
	qfglRotatef (-e->angles[0], 0, 1, 0);
	// ZOID: fixed z angle
	qfglRotatef (e->angles[2], 1, 0, 0);
}

static mspriteframe_t *
R_GetSpriteFrame (entity_t *currententity)
{
	float           fullinterval, targettime, time;
	float          *pintervals;
	int             frame, numframes, i;
	msprite_t      *psprite;
	mspriteframe_t *pspriteframe;
	mspritegroup_t *pspritegroup;

	psprite = currententity->model->cache.data;
	frame = currententity->frame;

	if ((frame >= psprite->numframes) || (frame < 0)) {
		Con_Printf ("R_DrawSprite: no such frame %d\n", frame);
		frame = 0;
	}

	if (psprite->frames[frame].type == SPR_SINGLE) {
		pspriteframe = psprite->frames[frame].frameptr;
	} else {
		pspritegroup = (mspritegroup_t *) psprite->frames[frame].frameptr;
		pintervals = pspritegroup->intervals;
		numframes = pspritegroup->numframes;
		fullinterval = pintervals[numframes - 1];

		time = r_realtime + currententity->syncbase;

		// when loading in Mod_LoadSpriteGroup, we guaranteed all interval
		// values
		// are positive, so we don't have to worry about division by 0
		targettime = time - ((int) (time / fullinterval)) * fullinterval;

		for (i = 0; i < (numframes - 1); i++) {
			if (pintervals[i] > targettime)
				break;
		}

		pspriteframe = pspritegroup->frames[i];
	}

	return pspriteframe;
}

static void
R_DrawSpriteModel (entity_t *e)
{
	float      *up, *right;
	msprite_t  *psprite;
	mspriteframe_t *frame;
	vec3_t      point, v_forward, v_right, v_up;

	// don't even bother culling, because it's just a single
	// polygon without a surface cache
	frame = R_GetSpriteFrame (e);
	psprite = currententity->model->cache.data;

	if (psprite->type == SPR_ORIENTED) {	// bullet marks on walls
		AngleVectors (currententity->angles, v_forward, v_right, v_up);
		up = v_up;
		right = v_right;
	} else {							// normal sprite
		up = vup;
		right = vright;
	}

	qfglBindTexture (GL_TEXTURE_2D, frame->gl_texturenum);

	qfglEnable (GL_ALPHA_TEST);
	qfglBegin (GL_QUADS);

	qfglTexCoord2f (0, 1);
	VectorMA (e->origin, frame->down, up, point);
	VectorMA (point, frame->left, right, point);
	qfglVertex3fv (point);

	qfglTexCoord2f (0, 0);
	VectorMA (e->origin, frame->up, up, point);
	VectorMA (point, frame->left, right, point);
	qfglVertex3fv (point);

	qfglTexCoord2f (1, 0);
	VectorMA (e->origin, frame->up, up, point);
	VectorMA (point, frame->right, right, point);
	qfglVertex3fv (point);

	qfglTexCoord2f (1, 1);
	VectorMA (e->origin, frame->down, up, point);
	VectorMA (point, frame->right, right, point);
	qfglVertex3fv (point);

	qfglEnd ();

	qfglDisable (GL_ALPHA_TEST);
}

/* ALIAS MODELS */

#define NUMVERTEXNORMALS	162

float       r_avertexnormals[NUMVERTEXNORMALS][3] = {
#include "anorms.h"
};

// precalculated dot products for quantized angles
#define SHADEDOT_QUANT 16
float   r_avertexnormal_dots[SHADEDOT_QUANT][256] =
	#include "anorm_dots.h"
		;

float       shadelight;
float      *shadedots = r_avertexnormal_dots[0];
int         lastposenum, lastposenum0;
vec3_t      shadevector;

static void
GL_DrawAliasFrame (vert_order_t *vo, qboolean fb)
{
	float           color[4];
	float           l;
	int             count;
	int            *order;
	blended_vert_t *verts;

	verts = vo->verts;
	order = vo->order;

	color[3] = modelalpha;

	if (modelalpha != 1.0)
		qfglDepthMask (GL_FALSE);

	if (fb) {
		color_white[3] = modelalpha * 255;
		qfglColor4ubv (color_white);
	}

	while ((count = *order++)) {
		// get the vertex count and primitive type
		if (count < 0) {
			count = -count;
			qfglBegin (GL_TRIANGLE_FAN);
		} else {
			qfglBegin (GL_TRIANGLE_STRIP);
		}

		do {
			// texture coordinates come from the draw list
			qfglTexCoord2fv ((float *) order);
			order += 2;

			if (!fb) {
				// normals and vertexes come from the frame list
				l = shadelight * verts->lightdot;
				VectorScale (shadecolor, l, color);

				qfglColor4fv (color);
			}

			qfglVertex3fv (verts->vert);
			verts++;
		} while (--count);

		qfglEnd ();
	}

	if (modelalpha != 1.0)
		qfglDepthMask (GL_TRUE);

}

extern vec3_t lightspot;

/*
	GL_DrawAliasShadow

	Standard shadow drawing
*/
static void
GL_DrawAliasShadow (aliashdr_t *paliashdr, int posenum)
{
	float       height, lheight;
	int         count;
	int        *order;
	vec3_t      point;
	trivertx_t *verts;

	lheight = currententity->origin[2] - lightspot[2];

	height = 0;
	verts = (trivertx_t *) ((byte *) paliashdr + paliashdr->posedata);
	verts += posenum * paliashdr->poseverts;
	order = (int *) ((byte *) paliashdr + paliashdr->commands);

	height = -lheight + 1.0;

	while ((count = *order++)) {
		// get the vertex count and primitive type

		if (count < 0) {
			count = -count;
			qfglBegin (GL_TRIANGLE_FAN);
		} else
			qfglBegin (GL_TRIANGLE_STRIP);

		do {
			// texture coordinates come from the draw list
			// (skipped for shadows) qfglTexCoord2fv ((float *)order);
			order += 2;

			// normals and vertexes come from the frame list
			point[0] =
				verts->v[0] * paliashdr->mdl.scale[0] +
				paliashdr->mdl.scale_origin[0];
			point[1] =
				verts->v[1] * paliashdr->mdl.scale[1] +
				paliashdr->mdl.scale_origin[1];
			point[2] =
				verts->v[2] * paliashdr->mdl.scale[2] +
				paliashdr->mdl.scale_origin[2];

			point[0] -= shadevector[0] * (point[2] + lheight);
			point[1] -= shadevector[1] * (point[2] + lheight);
			point[2] = height;
//			height -= 0.001;
			qfglVertex3fv (point);

			verts++;
		} while (--count);

		qfglEnd ();
	}
}

/*
	GL_DrawAliasBlendedShadow
         
	Interpolated shadow drawing
*/
void
GL_DrawAliasBlendedShadow (aliashdr_t *paliashdr, int pose1, int pose2,
						   entity_t *e)
{
	float       blend, height, lheight, lerp;
	int         count;
	int 	   *order;
	trivertx_t *verts1, *verts2;
	vec3_t		point1, point2;

	blend = (r_realtime - e->frame_start_time) / e->frame_interval;
	blend = min (blend, 1);
	lerp = 1 - blend;

	lheight = e->origin[2] - lightspot[2];
	height = -lheight + 1.0;

	verts2 = verts1 = (trivertx_t *) ((byte *) paliashdr +
									  paliashdr->posedata);

	verts1 += pose1 * paliashdr->poseverts;
	verts2 += pose2 * paliashdr->poseverts;

	order = (int *) ((byte *) paliashdr + paliashdr->commands);

	while ((count = *order++)) {
		// get the vertex count and primitive type
		if (count < 0) {
			count = -count;
			qfglBegin (GL_TRIANGLE_FAN);
		} else {
			qfglBegin (GL_TRIANGLE_STRIP);
		}

		do {
			order += 2;

			point1[0] =	verts1->v[0] * paliashdr->mdl.scale[0] +
				paliashdr->mdl.scale_origin[0];
			point1[1] =	verts1->v[1] * paliashdr->mdl.scale[1] +
				paliashdr->mdl.scale_origin[1];
			point1[2] =	verts1->v[2] * paliashdr->mdl.scale[2] +
				paliashdr->mdl.scale_origin[2];

			point1[0] -= shadevector[0] * (point1[2] + lheight);
			point1[1] -= shadevector[1] * (point1[2] + lheight);

			point2[0] =	verts2->v[0] * paliashdr->mdl.scale[0] +
				paliashdr->mdl.scale_origin[0];
			point2[1] =	verts2->v[1] * paliashdr->mdl.scale[1] +
				paliashdr->mdl.scale_origin[1];
			point2[2] =	verts2->v[2] * paliashdr->mdl.scale[2] +
				paliashdr->mdl.scale_origin[2];

			point2[0] -= shadevector[0] * (point2[2] + lheight);
			point2[1] -= shadevector[1] * (point2[2] + lheight);

			qfglVertex3f ((point1[0] * lerp) + (point2[0] * blend),
						(point1[1] * lerp) + (point2[1] * blend),
						height);

			verts1++;
			verts2++;
		} while (--count);
		qfglEnd ();
	}
}

vert_order_t *
GL_GetAliasFrameVerts (int frame, aliashdr_t *paliashdr, entity_t *e)
{
	float       interval;
	int         count, numposes, pose, i;
	trivertx_t *verts;
	vert_order_t *vo;

	if ((frame >= paliashdr->mdl.numframes) || (frame < 0)) {
		Con_DPrintf ("R_AliasSetupFrame: no such frame %d\n", frame);
		frame = 0;
	}

	pose = paliashdr->frames[frame].firstpose;
	numposes = paliashdr->frames[frame].numposes;

	verts = (trivertx_t *) ((byte *) paliashdr + paliashdr->posedata);

	count = paliashdr->poseverts;
	vo = Hunk_TempAlloc (sizeof (*vo) + count * sizeof (blended_vert_t));
	vo->order = (int *) ((byte *) paliashdr + paliashdr->commands);
	vo->verts = (blended_vert_t*)&vo[1];

	if (numposes > 1) {
		interval = paliashdr->frames[frame].interval;
		pose += (int) (r_realtime / interval) % numposes;
	} else {
		/*
			One tenth of a second is good for most Quake animations. If
			the nextthink is longer then the animation is usually meant
			to pause (e.g. check out the shambler magic animation in
			shambler.qc).  If its shorter then things will still be
			smoothed partly, and the jumps will be less noticable
			because of the shorter time.  So, this is probably a good
			assumption.
		*/
		interval = 0.1;
	}

	if (gl_lerp_anim->int_val) {
		trivertx_t *verts1, *verts2;
		float       blend, lerp;

		e->frame_interval = interval;

		if (e->pose2 != pose) {
			e->frame_start_time = r_realtime;
			if (e->pose2 == -1) {
				e->pose1 = pose;
			} else {
				e->pose1 = e->pose2;
			}
			e->pose2 = pose;
			blend = 0;
		} else {
			blend = (r_realtime - e->frame_start_time) / e->frame_interval;
		}

		// wierd things start happening if blend passes 1
		if (r_paused || blend > 1)
			blend = 1;
		lerp = 1 - blend;

		verts1 = verts + e->pose1 * count;
		verts2 = verts + e->pose2 * count;

		if (!blend) {
			verts = verts1;
		} else if (blend == 1) {
			verts = verts2;
		} else {
			for (i = 0; i < count; i++) {
				vo->verts[i].vert[0] = verts1[i].v[0] * lerp
										+ verts2[i].v[0] * blend;
				vo->verts[i].vert[1] = verts1[i].v[1] * lerp
										+ verts2[i].v[1] * blend;
				vo->verts[i].vert[2] = verts1[i].v[2] * lerp
										+ verts2[i].v[2] * blend;
				vo->verts[i].lightdot =
					shadedots[verts1[i].lightnormalindex] * lerp
					+ shadedots[verts2[i].lightnormalindex] * blend;
			}
			lastposenum0 = e->pose1;
			lastposenum = e->pose2;
			return vo;
		}
	}
	for (i = 0; i < count; i++) {
		vo->verts[i].vert[0] = verts[i].v[0];
		vo->verts[i].vert[1] = verts[i].v[1];
		vo->verts[i].vert[2] = verts[i].v[2];
		vo->verts[i].lightdot = shadedots[verts[i].lightnormalindex];
	}
	lastposenum = pose;
	return vo;
}

static void
R_DrawAliasModel (entity_t *e, qboolean cull)
{
	float       add, an;
	int         anim, lnum, skinnum, texture;
	int         fb_texture = 0;
	aliashdr_t *paliashdr;
	model_t    *clmodel;
	qboolean	modelIsFullbright = false;
	vec3_t      dist, mins, maxs;
	vert_order_t *vo;

	clmodel = currententity->model;

	VectorAdd (currententity->origin, clmodel->mins, mins);
	VectorAdd (currententity->origin, clmodel->maxs, maxs);

	if (cull && R_CullBox (mins, maxs))
		return;

	/*
	if (cull && R_CullBlocked(mins, maxs, currententity->origin))
		return;
		*/

	// FIXME: shadecolor is supposed to be the lighting for the model, not
	// just colormod
	shadecolor[0] = currententity->colormod[0] * 2.0;
	shadecolor[1] = currententity->colormod[1] * 2.0;
	shadecolor[2] = currententity->colormod[2] * 2.0;

	VectorCopy (currententity->origin, r_entorigin);
	VectorSubtract (r_origin, r_entorigin, modelorg);

	// get lighting information
	shadelight = R_LightPoint (currententity->origin);

	// always give the gun some light
	if (e == r_view_model)
		shadelight = max (shadelight, 24);

	for (lnum = 0; lnum < MAX_DLIGHTS; lnum++) {
		if (r_dlights[lnum].die >= r_realtime) {
			VectorSubtract (currententity->origin, r_dlights[lnum].origin,
							dist);
			add = (r_dlights[lnum].radius * r_dlights[lnum].radius * 8) /
				(DotProduct (dist, dist));	// FIXME Deek

			if (add > 0)
				shadelight += add;
		}
	}

	// clamp lighting so it doesn't overbright as much
	shadelight = min (shadelight, 100); // was 200

	// never allow players to go totally black
	if (strequal (clmodel->name, "progs/player.mdl")) {
		shadelight = max (shadelight, 8);
	}
	
	if (strnequal (clmodel->name, "progs/flame", 11)
			|| strnequal (clmodel->name, "progs/bolt", 10)) {
		modelIsFullbright = true;
		shadelight = 255;	// make certain models full brightness always
	}

	shadedots = r_avertexnormal_dots[(int) (e->angles[1] *
											(SHADEDOT_QUANT / 360.0)) &
									 (SHADEDOT_QUANT - 1)];
	shadelight /= 200.0;

	an = e->angles[1] / 180 * M_PI;
	shadevector[0] = cos (-an);
	shadevector[1] = sin (-an);
	shadevector[2] = 1;
	VectorNormalize (shadevector);

	// locate the proper data
	paliashdr = Cache_Get (&currententity->model->cache);
	c_alias_polys += paliashdr->mdl.numtris;

	// draw all the triangles
	qfglPushMatrix ();
	R_RotateForEntity (e);

	if (strequal (clmodel->name, "progs/eyes.mdl")) {
		qfglTranslatef (paliashdr->mdl.scale_origin[0],
					  paliashdr->mdl.scale_origin[1],
					  paliashdr->mdl.scale_origin[2] - (22 + 8));
		// double size of eyes, since they are really hard to see in GL
		qfglScalef (paliashdr->mdl.scale[0] * 2, paliashdr->mdl.scale[1] * 2,
				  paliashdr->mdl.scale[2] * 2);
	} else {
		qfglTranslatef (paliashdr->mdl.scale_origin[0],
					  paliashdr->mdl.scale_origin[1],
					  paliashdr->mdl.scale_origin[2]);
		qfglScalef (paliashdr->mdl.scale[0], paliashdr->mdl.scale[1],
				  paliashdr->mdl.scale[2]);
	}

	anim = (int) (r_realtime * 10) & 3;

	skinnum = currententity->skinnum;
	if ((skinnum >= paliashdr->mdl.numskins) || (skinnum < 0)) {
		Con_DPrintf ("R_AliasSetupSkin: no such skin # %d\n", skinnum);
		skinnum = 0;
	}

	texture = paliashdr->gl_texturenum[skinnum][anim];
	if (gl_fb_models->int_val && !modelIsFullbright)
		fb_texture = paliashdr->gl_fb_texturenum[skinnum][anim];

	// we can't dynamically colormap textures, so they are cached
	// seperately for the players.  Heads are just uncolored.
	if (currententity->skin && !gl_nocolors->int_val) {
		skin_t *skin = currententity->skin;

		texture = skin->texture;
		if (gl_fb_models->int_val) {
			fb_texture = skin->fb_texture;
		}
	}

	qfglBindTexture (GL_TEXTURE_2D, texture);

	if (gl_affinemodels->int_val)
		qfglHint (GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);

	vo = GL_GetAliasFrameVerts (currententity->frame, paliashdr,
								currententity);

	GL_DrawAliasFrame (vo, false);

	// This block is GL fullbright support for objects...
	if (fb_texture) {
		qfglBindTexture (GL_TEXTURE_2D, fb_texture);
		GL_DrawAliasFrame (vo, true);
	}

	if (gl_affinemodels->int_val)
		qfglHint (GL_PERSPECTIVE_CORRECTION_HINT, GL_DONT_CARE);

	qfglPopMatrix ();

	if (r_shadows->int_val) {
		// torches, grenades, and lightning bolts do not have shadows
		if (modelIsFullbright)
			return;
		if (strequal (clmodel->name, "progs/grenade.mdl"))
			return;

		qfglPushMatrix ();
		R_RotateForEntity (e);

		qfglDisable (GL_TEXTURE_2D);
		color_black[3] = 128;
		qfglColor4ubv (color_black);

		if (gl_lerp_anim->int_val) {
			GL_DrawAliasBlendedShadow (paliashdr, lastposenum0, lastposenum,
									   currententity);
		} else {
			GL_DrawAliasShadow (paliashdr, lastposenum);
		}

		qfglEnable (GL_TEXTURE_2D);
		qfglPopMatrix ();
	}

	Cache_Release (&currententity->model->cache);
}

/*
	R_ShowNearestLoc

	Display the nearest symbolic location (.loc files)
*/
static void
R_ShowNearestLoc (void)
{
	dlight_t	*dl;
	location_t	*nearloc;
	vec3_t		 trueloc;

	if (r_drawentities->int_val)
		return;

	nearloc = locs_find (r_origin);

	if (nearloc) {
		dl = R_AllocDlight (4096);
		VectorCopy (nearloc->loc, dl->origin);
		dl->radius = 200;
		dl->die = r_realtime + 0.1;
		dl->color[0] = 0;
		dl->color[1] = 1;
		dl->color[2] = 0;

		VectorCopy (nearloc->loc, trueloc);
		R_RunSpikeEffect (trueloc, 7);
	}
}

/*
	R_DrawEntitiesOnList

	Draw all the entities we have information on.
*/
static void
R_DrawEntitiesOnList (void)
{
	int         i;

	if (!r_drawentities->int_val) {
		R_ShowNearestLoc();
		return;
	}

	// LordHavoc: split into 3 loops to simplify state changes
	for (i = 0; i < r_numvisedicts; i++) {
		if (r_visedicts[i]->model->type != mod_brush)
			continue;
		currententity = r_visedicts[i];
		modelalpha = currententity->alpha;

		R_DrawBrushModel (currententity);
	}

	for (i = 0; i < r_numvisedicts; i++) {
		if (r_visedicts[i]->model->type != mod_alias)
			continue;
		currententity = r_visedicts[i];
		modelalpha = currententity->alpha;

		if (currententity == r_player_entity)
			currententity->angles[PITCH] *= 0.3;

		R_DrawAliasModel (currententity, true);
	}
	qfglColor3ubv (color_white);

	for (i = 0; i < r_numvisedicts; i++) {
		if (r_visedicts[i]->model->type != mod_sprite)
			continue;
		currententity = r_visedicts[i];
		modelalpha = currententity->alpha;

		R_DrawSpriteModel (currententity);
	}
}

static void
R_DrawViewModel (void)
{
	currententity = r_view_model;
	if (r_inhibit_viewmodel
		|| !r_drawviewmodel->int_val
		|| envmap
		|| !r_drawentities->int_val
		|| !currententity->model)
		return;

	// this is a HACK!  --KB
	modelalpha = currententity->alpha;

	// hack the depth range to prevent view model from poking into walls
	qfglDepthRange (gldepthmin, gldepthmin + 0.3 * (gldepthmax - gldepthmin));
	R_DrawAliasModel (currententity, false);
	qfglDepthRange (gldepthmin, gldepthmax);
	qfglColor3ubv (color_white);
}

inline static int
SignbitsForPlane (mplane_t *out)
{
	int         bits, j;

	// for fast box on planeside test

	bits = 0;
	for (j = 0; j < 3; j++) {
		if (out->normal[j] < 0)
			bits |= 1 << j;
	}
	return bits;
}

static void
R_SetFrustum (void)
{
	int         i;

	if (r_refdef.fov_x == 90) {
		// front side is visible

		VectorAdd (vpn, vright, frustum[0].normal);
		VectorSubtract (vpn, vright, frustum[1].normal);

		VectorAdd (vpn, vup, frustum[2].normal);
		VectorSubtract (vpn, vup, frustum[3].normal);
	} else {

		// rotate VPN right by FOV_X/2 degrees
		RotatePointAroundVector (frustum[0].normal, vup, vpn,
								 -(90 - r_refdef.fov_x / 2));
		// rotate VPN left by FOV_X/2 degrees
		RotatePointAroundVector (frustum[1].normal, vup, vpn,
								 90 - r_refdef.fov_x / 2);
		// rotate VPN up by FOV_X/2 degrees
		RotatePointAroundVector (frustum[2].normal, vright, vpn,
								 90 - r_refdef.fov_y / 2);
		// rotate VPN down by FOV_X/2 degrees
		RotatePointAroundVector (frustum[3].normal, vright, vpn,
								 -(90 - r_refdef.fov_y / 2));
	}

	for (i = 0; i < 4; i++) {
		frustum[i].type = PLANE_ANYZ;
		frustum[i].dist = DotProduct (r_origin, frustum[i].normal);
		frustum[i].signbits = SignbitsForPlane (&frustum[i]);
	}
}

void
R_SetupFrame (void)
{
	R_AnimateLight ();

	r_framecount++;

	// build the transformation matrix for the given view angles
	VectorCopy (r_refdef.vieworg, r_origin);

	AngleVectors (r_refdef.viewangles, vpn, vright, vup);

	// current viewleaf
	r_oldviewleaf = r_viewleaf;
	r_viewleaf = Mod_PointInLeaf (r_origin, r_worldentity.model);

	V_SetContentsColor (r_viewleaf->contents);

	r_cache_thrash = false;

	c_brush_polys = 0;
	c_alias_polys = 0;

}

static void
MYgluPerspective (GLdouble fovy, GLdouble aspect, GLdouble zNear, GLdouble zFar)
{
	GLdouble    xmin, xmax, ymin, ymax;

	ymax = zNear * tan (fovy * M_PI / 360.0);
	ymin = -ymax;

	xmin = ymin * aspect;
	xmax = ymax * aspect;

	qfglFrustum (xmin, xmax, ymin, ymax, zNear, zFar);
}

static void
R_SetupGL (void)
{
	float		screenaspect;
	int			x, x2, y2, y, w, h;
	extern int	glwidth, glheight;

	// set up viewpoint
	qfglMatrixMode (GL_PROJECTION);
	qfglLoadIdentity ();
	x = r_refdef.vrect.x * glwidth / vid.width;
	x2 = (r_refdef.vrect.x + r_refdef.vrect.width) * glwidth / vid.width;
	y = (vid.height - r_refdef.vrect.y) * glheight / vid.height;
	y2 = (vid.height - (r_refdef.vrect.y + r_refdef.vrect.height)) * glheight
		/ vid.height;

	// fudge around because of frac screen scale
	if (x > 0)
		x--;
	if (x2 < glwidth)
		x2++;
	if (y2 < 0)
		y2--;
	if (y < glheight)
		y++;

	w = x2 - x;
	h = y - y2;

	if (envmap) {
		x = y2 = 0;
		w = h = 256;
	}

	qfglViewport (glx + x, gly + y2, w, h);
	screenaspect = (float) r_refdef.vrect.width / r_refdef.vrect.height;
	MYgluPerspective (r_refdef.fov_y, screenaspect, 4, 4096);

	if (mirror) {
		if (mirror_plane->normal[2])
			qfglScalef (1, -1, 1);
		else
			qfglScalef (-1, 1, 1);
		qfglCullFace (GL_BACK);
	} else
		qfglCullFace (GL_FRONT);

	qfglMatrixMode (GL_MODELVIEW);
	qfglLoadIdentity ();

	qfglRotatef (-90, 1, 0, 0);			// put Z going up
	qfglRotatef (90, 0, 0, 1);			// put Z going up
	qfglRotatef (-r_refdef.viewangles[2], 1, 0, 0);
	qfglRotatef (-r_refdef.viewangles[0], 0, 1, 0);
	qfglRotatef (-r_refdef.viewangles[1], 0, 0, 1);
	qfglTranslatef (-r_refdef.vieworg[0], -r_refdef.vieworg[1],
				  -r_refdef.vieworg[2]);

	qfglGetFloatv (GL_MODELVIEW_MATRIX, r_world_matrix);

	// set drawing parms
	qfglEnable (GL_CULL_FACE);
	qfglDisable (GL_ALPHA_TEST);
	qfglAlphaFunc (GL_GREATER, 0.5);
	qfglEnable (GL_DEPTH_TEST);
	if (gl_dlight_smooth->int_val)
		qfglShadeModel (GL_SMOOTH);
	else
		qfglShadeModel (GL_FLAT);
}

static void
R_Clear (void)
{
	if (gl_clear->int_val)
		qfglClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	else
		qfglClear (GL_DEPTH_BUFFER_BIT);
	gldepthmin = 0;
	gldepthmax = 1;
	qfglDepthFunc (GL_LEQUAL);

	qfglDepthRange (gldepthmin, gldepthmax);
}

void
R_RenderScene (void)
{
	if (r_timegraph->int_val || r_speeds->int_val || r_dspeeds->int_val)
		r_time1 = Sys_DoubleTime ();

	R_SetupFrame ();

	R_SetFrustum ();

	R_SetupGL ();

	R_MarkLeaves ();			// done here so we know if we're in water

	R_PushDlights (vec3_origin);

	R_DrawWorld ();				// adds static entities to the list

	S_ExtraUpdate ();			// don't let sound get messed up if going slow

	R_DrawEntitiesOnList ();

	R_RenderDlights ();
}

void R_RenderBrushPoly (msurface_t *fa);

void
R_Mirror (void)
{
	float        d;
	entity_t   **ent;
	msurface_t  *s;

	if (!mirror)
		return;

	memcpy (r_base_world_matrix, r_world_matrix, sizeof (r_base_world_matrix));

	d = DotProduct (r_refdef.vieworg, mirror_plane->normal) -
		mirror_plane->dist;
	VectorMA (r_refdef.vieworg, -2 * d, mirror_plane->normal,
			  r_refdef.vieworg);

	d = DotProduct (vpn, mirror_plane->normal);
	VectorMA (vpn, -2 * d, mirror_plane->normal, vpn);

	r_refdef.viewangles[0] = -asin (vpn[2]) / M_PI * 180;
	r_refdef.viewangles[1] = atan2 (vpn[1], vpn[0]) / M_PI * 180;
	r_refdef.viewangles[2] = -r_refdef.viewangles[2];

	ent = R_NewEntity();
	if (ent)
		*ent = r_player_entity;

	gldepthmin = 0.5;
	gldepthmax = 1;
	qfglDepthRange (gldepthmin, gldepthmax);
	qfglDepthFunc (GL_LEQUAL);

	R_RenderScene ();
	R_DrawWaterSurfaces ();

	gldepthmin = 0;
	gldepthmax = 1;								// XXX 0.5;
	qfglDepthRange (gldepthmin, gldepthmax);
	qfglDepthFunc (GL_LEQUAL);

	// blend on top
	qfglMatrixMode (GL_PROJECTION);
	if (mirror_plane->normal[2])
		qfglScalef (1, -1, 1);
	else
		qfglScalef (-1, 1, 1);
	qfglCullFace (GL_FRONT);
	qfglMatrixMode (GL_MODELVIEW);

	qfglLoadMatrixf (r_base_world_matrix);

	color_white[2] = r_mirroralpha->value * 255;
	qfglColor4ubv (color_white);
	s = r_worldentity.model->textures[mirrortexturenum]->texturechain;
	for (; s; s = s->texturechain)
		R_RenderBrushPoly (s);
	r_worldentity.model->textures[mirrortexturenum]->texturechain = NULL;
	qfglColor3ubv (color_white);
}

/*
	R_RenderView

	r_refdef must be set before the first call
*/
void
R_RenderView (void)
{
	if (r_norefresh->int_val)
		return;

	if (!r_worldentity.model)
		Sys_Error ("R_RenderView: NULL worldmodel");

//	qfglFinish ();

	mirror = false;

	R_Clear ();

	// render normal view
	R_RenderScene ();

	R_DrawWaterSurfaces ();

	R_UpdateFires ();

	R_DrawParticles ();

	R_DrawViewModel ();

	// render mirror view
	R_Mirror ();

	if (r_timegraph->int_val)
		R_TimeGraph ();

	if (r_zgraph->int_val)
		R_ZGraph ();
}

#if 0
qboolean
R_CullBlocked (vec3_t mins, vec3_t maxs, vec3_t org)
{
	float   rad;
	static struct trace_t  trace;
	vec3_t  point;

	if (!gl_occlusion->int_val)
		return false;

	// Check the origin first
	if ( Mod_PointInLeaf(org, cl.worldmodel)->contents != CONTENTS_SOLID)
	{
		if (SV_RecursiveHullCheck (cl.worldmodel->hulls, 0, 0, 1,
								   r_refdef.vieworg, org, &trace))
			return false;
	}

	rad = sqrt((maxs[0]-org[0])*(maxs[0]-org[0]) +
			(maxs[1]-org[1])*(maxs[1]-org[1]) +
			(maxs[2]-org[2])*(maxs[2]-org[2]) );

	// Check a few points on the bounding sphere to catch rotating objects
	// Raise the origin a bit to catch droptofloor models
	point[0] = org[0]; point[1] = org[1]+rad; point[2] = org[2]+4;
	if ( Mod_PointInLeaf(point, cl.worldmodel)->contents != CONTENTS_SOLID)
	{
		if (SV_RecursiveHullCheck (cl.worldmodel->hulls, 0, 0, 1,
								   r_refdef.vieworg, point, &trace))
			return false;
	}
	point[0] = org[0]+rad; point[1] = org[1]; point[2] = org[2]+4;
	if ( Mod_PointInLeaf(point, cl.worldmodel)->contents != CONTENTS_SOLID)
	{
		if (SV_RecursiveHullCheck (cl.worldmodel->hulls, 0, 0, 1,
								   r_refdef.vieworg, point, &trace))
			return false;
	}
	point[0] = org[0]; point[1] = org[1]-rad; point[2] = org[2]+4;
	if ( Mod_PointInLeaf(point, cl.worldmodel)->contents != CONTENTS_SOLID)
	{
		if (SV_RecursiveHullCheck (cl.worldmodel->hulls, 0, 0, 1,
								   r_refdef.vieworg, point, &trace))
			return false;
	}
	point[0] = org[0]-rad; point[1] = org[1]; point[2] = org[2]+4;
	if ( Mod_PointInLeaf(point, cl.worldmodel)->contents != CONTENTS_SOLID)
	{
		if (SV_RecursiveHullCheck (cl.worldmodel->hulls, 0, 0, 1,
								   r_refdef.vieworg, point, &trace))
			return false;
	}

	// Check the poles of the sphere (can catch ents on ledges that would
	// otherwise be missed)
	point[0] = org[0]; point[1] = org[1]; point[2] = org[2]+rad;
	if ( Mod_PointInLeaf(point, cl.worldmodel)->contents != CONTENTS_SOLID)
	{
		if (SV_RecursiveHullCheck (cl.worldmodel->hulls, 0, 0, 1,
								   r_refdef.vieworg, point, &trace))
			return false;
	}
	point[0] = org[0]; point[1] = org[1]; point[2] = org[2]-rad;
	if ( Mod_PointInLeaf(point, cl.worldmodel)->contents != CONTENTS_SOLID)
	{
		if (SV_RecursiveHullCheck (cl.worldmodel->hulls, 0, 0, 1,
								   r_refdef.vieworg, point, &trace))
			return false;
	}


	// Check the corners...
	if ( Mod_PointInLeaf(maxs, cl.worldmodel)->contents != CONTENTS_SOLID)
	{
		if (SV_RecursiveHullCheck (cl.worldmodel->hulls, 0, 0, 1,
								   r_refdef.vieworg, maxs, &trace))
			return false;
	}
	point[0] = mins[0]; point[1] = maxs[1]; point[2] = maxs[2];
	if ( Mod_PointInLeaf(point, cl.worldmodel)->contents != CONTENTS_SOLID)
	{
		if (SV_RecursiveHullCheck (cl.worldmodel->hulls, 0, 0, 1,
								   r_refdef.vieworg, point, &trace))
			return false;
	}
	point[0] = mins[0]; point[1] = mins[1]; point[2] = maxs[2];
	if ( Mod_PointInLeaf(point, cl.worldmodel)->contents != CONTENTS_SOLID)
	{
		if (SV_RecursiveHullCheck (cl.worldmodel->hulls, 0, 0, 1,
								   r_refdef.vieworg, point, &trace))
			return false;
	}
	point[0] = maxs[0]; point[1] = mins[1]; point[2] = maxs[2];
	if ( Mod_PointInLeaf(point, cl.worldmodel)->contents != CONTENTS_SOLID)
	{
		if (SV_RecursiveHullCheck (cl.worldmodel->hulls, 0, 0, 1,
								   r_refdef.vieworg, point, &trace))
			return false;
	}
	if ( Mod_PointInLeaf(mins, cl.worldmodel)->contents != CONTENTS_SOLID)
	{
		if (SV_RecursiveHullCheck (cl.worldmodel->hulls, 0, 0, 1,
								   r_refdef.vieworg, mins, &trace))
			return false;
	}
	point[0] = mins[0]; point[1] = maxs[1]; point[2] = mins[2]+4;
	if ( Mod_PointInLeaf(point, cl.worldmodel)->contents != CONTENTS_SOLID)
	{
		if (SV_RecursiveHullCheck (cl.worldmodel->hulls, 0, 0, 1,
								   r_refdef.vieworg, point, &trace))
			return false;
	}
	point[0] = maxs[0]; point[1] = mins[1]; point[2] = mins[2]+4;
	if ( Mod_PointInLeaf(point, cl.worldmodel)->contents != CONTENTS_SOLID)
	{
		if (SV_RecursiveHullCheck (cl.worldmodel->hulls, 0, 0, 1,
								   r_refdef.vieworg, point, &trace))
			return false;
	}
	point[0] = maxs[0]; point[1] = maxs[1]; point[2] = mins[2]+4;
	if ( Mod_PointInLeaf(point, cl.worldmodel)->contents != CONTENTS_SOLID)
	{
		if (SV_RecursiveHullCheck (cl.worldmodel->hulls, 0, 0, 1,
								   r_refdef.vieworg, point, &trace))
			return false;
	}

	// Model is blocked (probably)
	return true;
}
#endif