/*
Copyright (C) 1996-2001 Id Software, Inc.
Copyright (C) 2002-2009 John Fitzgibbons and others
Copyright (C) 2010-2014 QuakeSpasm developers

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.

*/
// r_main.c

#include "q_defs.h"

bool    r_cache_thrash;         // compatability

vec3_t          modelorg, r_entorigin;
entity_t        *currententity;

int32_t                 r_visframecount;        // bumped when going to a new PVS
int32_t                 r_framecount;           // used for dlight push checking

mplane_t        frustum[4];

//johnfitz -- rendering statistics
int32_t rs_brushpolys, rs_aliaspolys, rs_skypolys, rs_particles, rs_fogpolys;
int32_t rs_dynamiclightmaps, rs_brushpasses, rs_aliaspasses, rs_skypasses;
float rs_megatexels;

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

float r_fovx, r_fovy; //johnfitz -- rendering fov may be different becuase of r_waterwarp and r_stereo

//
// screen size info
//
refdef_t        r_refdef;

mleaf_t         *r_viewleaf, *r_oldviewleaf;

int32_t         d_lightstylevalue[256]; // 8.8 fraction of base light value


cvar_t  r_norefresh = {"r_norefresh", "0", CVAR_NONE};
cvar_t  r_drawentities = {"r_drawentities", "1", CVAR_NONE};
cvar_t  r_drawviewmodel = {"r_drawviewmodel", "1", CVAR_NONE};
cvar_t  r_speeds = {"r_speeds", "0", CVAR_NONE};
cvar_t  r_pos = {"r_pos", "0", CVAR_NONE};
cvar_t  r_fullbright = {"r_fullbright", "0", CVAR_NONE};
cvar_t  r_lightmap = {"r_lightmap", "0", CVAR_NONE};
cvar_t  r_shadows = {"r_shadows", "0", CVAR_ARCHIVE};
cvar_t  r_wateralpha = {"r_wateralpha", "1", CVAR_ARCHIVE};
cvar_t  r_dynamic = {"r_dynamic", "1", CVAR_ARCHIVE};
cvar_t  r_novis = {"r_novis", "0", CVAR_ARCHIVE};

cvar_t  gl_finish = {"gl_finish", "0", CVAR_NONE};
cvar_t  gl_clear = {"gl_clear", "1", CVAR_NONE};
cvar_t  gl_cull = {"gl_cull", "1", CVAR_NONE};
cvar_t  gl_smoothmodels = {"gl_smoothmodels", "1", CVAR_NONE};
cvar_t  gl_affinemodels = {"gl_affinemodels", "0", CVAR_NONE};
cvar_t  gl_polyblend = {"gl_polyblend", "1", CVAR_NONE};
cvar_t  gl_flashblend = {"gl_flashblend", "0", CVAR_ARCHIVE};
cvar_t  gl_playermip = {"gl_playermip", "0", CVAR_NONE};
cvar_t  gl_nocolors = {"gl_nocolors", "0", CVAR_NONE};

//johnfitz -- new cvars
cvar_t  r_stereo = {"r_stereo", "0", CVAR_NONE};
cvar_t  r_stereodepth = {"r_stereodepth", "128", CVAR_NONE};
cvar_t  r_clearcolor = {"r_clearcolor", "2", CVAR_ARCHIVE};
cvar_t  r_drawflat = {"r_drawflat", "0", CVAR_NONE};
cvar_t  r_flatlightstyles = {"r_flatlightstyles", "0", CVAR_NONE};
cvar_t  gl_fullbrights = {"gl_fullbrights", "1", CVAR_ARCHIVE};
cvar_t  gl_farclip = {"gl_farclip", "16384", CVAR_ARCHIVE};
cvar_t  gl_overbright = {"gl_overbright", "1", CVAR_ARCHIVE};
cvar_t  gl_overbright_models = {"gl_overbright_models", "1", CVAR_ARCHIVE};
cvar_t  r_oldskyleaf = {"r_oldskyleaf", "0", CVAR_NONE};
cvar_t  r_drawworld = {"r_drawworld", "1", CVAR_NONE};
cvar_t  r_showtris = {"r_showtris", "0", CVAR_NONE};
cvar_t  r_showbboxes = {"r_showbboxes", "0", CVAR_NONE};
cvar_t  r_lerpmodels = {"r_lerpmodels", "1", CVAR_NONE};
cvar_t  r_lerpmove = {"r_lerpmove", "1", CVAR_NONE};
cvar_t  r_nolerp_list = {"r_nolerp_list", "progs/flame.mdl,progs/flame2.mdl,progs/braztall.mdl,progs/brazshrt.mdl,progs/longtrch.mdl,progs/flame_pyre.mdl,progs/v_saw.mdl,progs/v_xfist.mdl,progs/h2stuff/newfire.mdl", CVAR_NONE};
cvar_t  r_noshadow_list = {"r_noshadow_list", "progs/flame2.mdl,progs/flame.mdl,progs/bolt1.mdl,progs/bolt2.mdl,progs/bolt3.mdl,progs/laser.mdl", CVAR_NONE};

extern cvar_t   r_vfog;
//johnfitz

cvar_t  gl_zfix = {"gl_zfix", "0", CVAR_NONE}; // QuakeSpasm z-fighting fix

cvar_t  r_lavaalpha = {"r_lavaalpha", "0", CVAR_NONE};
cvar_t  r_telealpha = {"r_telealpha", "0", CVAR_NONE};
cvar_t  r_slimealpha = {"r_slimealpha", "0", CVAR_NONE};

float   map_wateralpha, map_lavaalpha, map_telealpha, map_slimealpha;

bool r_drawflat_cheatsafe, r_fullbright_cheatsafe, r_lightmap_cheatsafe, r_drawworld_cheatsafe; //johnfitz

cvar_t  r_scale = {"r_scale", "1", CVAR_ARCHIVE};

//==============================================================================
//
// GLSL GAMMA CORRECTION
//
//==============================================================================

static GLuint r_gamma_texture;
static GLuint r_gamma_program;
static int32_t r_gamma_texture_width, r_gamma_texture_height;

// uniforms used in gamma shader
static GLuint gammaLoc;
static GLuint contrastLoc;
static GLuint textureLoc;

/*
=============
GLSLGamma_DeleteTexture
=============
*/
void GLSLGamma_DeleteTexture(void)
{
	glDeleteTextures(1, &r_gamma_texture);
	r_gamma_texture = 0;
	r_gamma_program = 0; // deleted in R_DeleteShaders
}

/*
=============
GLSLGamma_CreateShaders
=============
*/
static void GLSLGamma_CreateShaders(void)
{
	const GLchar *vertSource = \
	                           "#version 110\n"
	                           "\n"
	                           "void main(void) {\n"
	                           "	gl_Position = vec4(gl_Vertex.xy, 0.0, 1.0);\n"
	                           "	gl_TexCoord[0] = gl_MultiTexCoord0;\n"
	                           "}\n";

	const GLchar *fragSource = \
	                           "#version 110\n"
	                           "\n"
	                           "uniform sampler2D GammaTexture;\n"
	                           "uniform float GammaValue;\n"
	                           "uniform float ContrastValue;\n"
	                           "\n"
	                           "void main(void) {\n"
	                           "	  vec4 frag = texture2D(GammaTexture, gl_TexCoord[0].xy);\n"
	                           "	  frag.rgb = frag.rgb * ContrastValue;\n"
	                           "	  gl_FragColor = vec4(pow(frag.rgb, vec3(GammaValue)), 1.0);\n"
	                           "}\n";

	if(!gl_glsl_gamma_able)
		return;

	r_gamma_program = GL_CreateProgram(vertSource, fragSource, 0, NULL);

// get uniform locations
	gammaLoc = GL_GetUniformLocation(&r_gamma_program, "GammaValue");
	contrastLoc = GL_GetUniformLocation(&r_gamma_program, "ContrastValue");
	textureLoc = GL_GetUniformLocation(&r_gamma_program, "GammaTexture");
}

/*
=============
GLSLGamma_GammaCorrect
=============
*/
void GLSLGamma_GammaCorrect(void)
{
	float smax, tmax;

	if(!gl_glsl_gamma_able)
		return;

	if(vid_gamma.value == 1 && vid_contrast.value == 1)
		return;

// create render-to-texture texture if needed
	if(!r_gamma_texture)
	{
		glGenTextures(1, &r_gamma_texture);
		glBindTexture(GL_TEXTURE_2D, r_gamma_texture);

		r_gamma_texture_width = glwidth;
		r_gamma_texture_height = glheight;

		if(!gl_texture_NPOT)
		{
			r_gamma_texture_width = TexMgr_Pad(r_gamma_texture_width);
			r_gamma_texture_height = TexMgr_Pad(r_gamma_texture_height);
		}

		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, r_gamma_texture_width, r_gamma_texture_height, 0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, NULL);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
	}

// create shader if needed
	if(!r_gamma_program)
	{
		GLSLGamma_CreateShaders();
		if(!r_gamma_program)
		{
			Sys_Error("GLSLGamma_CreateShaders failed");
		}
	}

// copy the framebuffer to the texture
	GL_DisableMultitexture();
	glBindTexture(GL_TEXTURE_2D, r_gamma_texture);
	glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, glx, gly, glwidth, glheight);

// draw the texture back to the framebuffer with a fragment shader
	GL_UseProgramFunc(r_gamma_program);
	GL_Uniform1fFunc(gammaLoc, vid_gamma.value);
	GL_Uniform1fFunc(contrastLoc, q_min(2.0, q_max(1.0, vid_contrast.value)));
	GL_Uniform1iFunc(textureLoc, 0);  // use texture unit 0

	glDisable(GL_ALPHA_TEST);
	glDisable(GL_DEPTH_TEST);

	glViewport(glx, gly, glwidth, glheight);

	smax = glwidth / (float)r_gamma_texture_width;
	tmax = glheight / (float)r_gamma_texture_height;

	glBegin(GL_QUADS);
	glTexCoord2f(0, 0);
	glVertex2f(-1, -1);
	glTexCoord2f(smax, 0);
	glVertex2f(1, -1);
	glTexCoord2f(smax, tmax);
	glVertex2f(1, 1);
	glTexCoord2f(0, tmax);
	glVertex2f(-1, 1);
	glEnd();

	GL_UseProgramFunc(0);

// clear cached binding
	GL_ClearBindings();
}

/*
=================
R_CullBox -- johnfitz -- replaced with new function from lordhavoc

Returns true if the box is completely outside the frustum
=================
*/
bool R_CullBox(vec3_t emins, vec3_t emaxs)
{
	int32_t i;
	mplane_t *p;
	for(i = 0; i < 4; i++)
	{
		p = frustum + i;
		switch(p->signbits)
		{
		default:
		case 0:
			if(p->normal[0]*emaxs[0] + p->normal[1]*emaxs[1] + p->normal[2]*emaxs[2] < p->dist)
				return true;
			break;
		case 1:
			if(p->normal[0]*emins[0] + p->normal[1]*emaxs[1] + p->normal[2]*emaxs[2] < p->dist)
				return true;
			break;
		case 2:
			if(p->normal[0]*emaxs[0] + p->normal[1]*emins[1] + p->normal[2]*emaxs[2] < p->dist)
				return true;
			break;
		case 3:
			if(p->normal[0]*emins[0] + p->normal[1]*emins[1] + p->normal[2]*emaxs[2] < p->dist)
				return true;
			break;
		case 4:
			if(p->normal[0]*emaxs[0] + p->normal[1]*emaxs[1] + p->normal[2]*emins[2] < p->dist)
				return true;
			break;
		case 5:
			if(p->normal[0]*emins[0] + p->normal[1]*emaxs[1] + p->normal[2]*emins[2] < p->dist)
				return true;
			break;
		case 6:
			if(p->normal[0]*emaxs[0] + p->normal[1]*emins[1] + p->normal[2]*emins[2] < p->dist)
				return true;
			break;
		case 7:
			if(p->normal[0]*emins[0] + p->normal[1]*emins[1] + p->normal[2]*emins[2] < p->dist)
				return true;
			break;
		}
	}
	return false;
}
/*
===============
R_CullModelForEntity -- johnfitz -- uses correct bounds based on rotation
===============
*/
bool R_CullModelForEntity(entity_t *e)
{
	vec3_t mins, maxs;

	if(e->angles[0] || e->angles[2])  //pitch or roll
	{
		VectorAdd(e->origin, e->model->rmins, mins);
		VectorAdd(e->origin, e->model->rmaxs, maxs);
	}
	else if(e->angles[1])  //yaw
	{
		VectorAdd(e->origin, e->model->ymins, mins);
		VectorAdd(e->origin, e->model->ymaxs, maxs);
	}
	else //no rotation
	{
		VectorAdd(e->origin, e->model->mins, mins);
		VectorAdd(e->origin, e->model->maxs, maxs);
	}

	return R_CullBox(mins, maxs);
}

/*
===============
R_RotateForEntity -- johnfitz -- modified to take origin and angles instead of pointer to entity
===============
*/
void R_RotateForEntity(vec3_t origin, vec3_t angles)
{
	glTranslatef(origin[0],  origin[1],  origin[2]);
	glRotatef(angles[1],  0, 0, 1);
	glRotatef(-angles[0],  0, 1, 0);
	glRotatef(angles[2],  1, 0, 0);
}

/*
=============
GL_PolygonOffset -- johnfitz

negative offset moves polygon closer to camera
=============
*/
void GL_PolygonOffset(int32_t offset)
{
	if(offset > 0)
	{
		glEnable(GL_POLYGON_OFFSET_FILL);
		glEnable(GL_POLYGON_OFFSET_LINE);
		glPolygonOffset(1, offset);
	}
	else if(offset < 0)
	{
		glEnable(GL_POLYGON_OFFSET_FILL);
		glEnable(GL_POLYGON_OFFSET_LINE);
		glPolygonOffset(-1, offset);
	}
	else
	{
		glDisable(GL_POLYGON_OFFSET_FILL);
		glDisable(GL_POLYGON_OFFSET_LINE);
	}
}

//==============================================================================
//
// SETUP FRAME
//
//==============================================================================

int32_t SignbitsForPlane(mplane_t *out)
{
	int32_t 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;
}

/*
===============
TurnVector -- johnfitz

turn forward towards side on the plane defined by forward and side
if angle = 90, the result will be equal to side
assumes side and forward are perpendicular, and normalized
to turn away from side, use a negative angle
===============
*/
#define DEG2RAD( a ) ( (a) * PI_DIV_180 )
void TurnVector(vec3_t out, const vec3_t forward, const vec3_t side, float angle)
{
	float scale_forward, scale_side;

	scale_forward = cos(DEG2RAD(angle));
	scale_side = sin(DEG2RAD(angle));

	out[0] = scale_forward * forward[0] + scale_side * side[0];
	out[1] = scale_forward * forward[1] + scale_side * side[1];
	out[2] = scale_forward * forward[2] + scale_side * side[2];
}

/*
===============
R_SetFrustum -- johnfitz -- rewritten
===============
*/
void R_SetFrustum(float fovx, float fovy)
{
	int32_t         i;

	if(r_stereo.value)
		fovx += 10; //silly hack so that polygons don't drop out becuase of stereo skew

	TurnVector(frustum[0].normal, vpn, vright, fovx / 2 - 90); //left plane
	TurnVector(frustum[1].normal, vpn, vright, 90 - fovx / 2); //right plane
	TurnVector(frustum[2].normal, vpn, vup, 90 - fovy / 2); //bottom plane
	TurnVector(frustum[3].normal, vpn, vup, fovy / 2 - 90); //top plane

	for(i = 0 ; i < 4 ; i++)
	{
		frustum[i].type = PLANE_ANYZ;
		frustum[i].dist = DotProduct(r_origin, frustum[i].normal);  //FIXME: shouldn't this always be zero?
		frustum[i].signbits = SignbitsForPlane(&frustum[i]);
	}
}

/*
=============
GL_SetFrustum -- johnfitz -- written to replace MYgluPerspective
=============
*/
#define NEARCLIP 4
float frustum_skew = 0.0; //used by r_stereo
void GL_SetFrustum(float fovx, float fovy)
{
	float xmax, ymax;
	xmax = NEARCLIP * tan(fovx * PI / 360.0);
	ymax = NEARCLIP * tan(fovy * PI / 360.0);
	glFrustum(-xmax + frustum_skew, xmax + frustum_skew, -ymax, ymax, NEARCLIP, gl_farclip.value);
}

/*
=============
R_SetupGL
=============
*/
void R_SetupGL(void)
{
	int32_t scale;

	//johnfitz -- rewrote this section
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	scale =  CLAMP(1, (int32_t)r_scale.value, 4); // ericw -- see R_ScaleView
	glViewport(glx + r_refdef.vrect.x,
	           gly + glheight - r_refdef.vrect.y - r_refdef.vrect.height,
	           r_refdef.vrect.width / scale,
	           r_refdef.vrect.height / scale);
	//johnfitz

	GL_SetFrustum(r_fovx, r_fovy);  //johnfitz -- use r_fov* vars

	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();

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

	//
	// set drawing parms
	//
	if(gl_cull.value)
		glEnable(GL_CULL_FACE);
	else
		glDisable(GL_CULL_FACE);

	glDisable(GL_BLEND);
	glDisable(GL_ALPHA_TEST);
	glEnable(GL_DEPTH_TEST);
}

/*
=============
R_Clear -- johnfitz -- rewritten and gutted
=============
*/
void R_Clear(void)
{
	uint32_t clearbits;

	clearbits = GL_DEPTH_BUFFER_BIT;
	// from mh -- if we get a stencil buffer, we should clear it, even though we don't use it
	if(gl_stencilbits)
		clearbits |= GL_STENCIL_BUFFER_BIT;
	if(gl_clear.value)
		clearbits |= GL_COLOR_BUFFER_BIT;
	glClear(clearbits);
}

/*
===============
R_SetupScene -- johnfitz -- this is the stuff that needs to be done once per eye in stereo mode
===============
*/
void R_SetupScene(void)
{
	R_PushDlights();
	R_AnimateLight();
	r_framecount++;
	R_SetupGL();
}

/*
===============
R_SetupView -- johnfitz -- this is the stuff that needs to be done once per frame, even in stereo mode
===============
*/
void R_SetupView(void)
{
	Fog_SetupFrame();  //johnfitz

// 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, cl.worldmodel);

	V_SetContentsColor(r_viewleaf->contents);
	V_CalcBlend();

	r_cache_thrash = false;

	//johnfitz -- calculate r_fovx and r_fovy here
	r_fovx = r_refdef.fov_x;
	r_fovy = r_refdef.fov_y;
	if(r_waterwarp.value)
	{
		int32_t contents = Mod_PointInLeaf(r_origin, cl.worldmodel)->contents;
		if(contents == CONTENTS_WATER || contents == CONTENTS_SLIME || contents == CONTENTS_LAVA)
		{
			//variance is a percentage of width, where width = 2 * tan(fov / 2) otherwise the effect is too dramatic at high FOV and too subtle at low FOV.  what a mess!
			r_fovx = atan(tan(DEG2RAD(r_refdef.fov_x) / 2) * (0.97 + sin(cl.time * 1.5) * 0.03)) * 2 / PI_DIV_180;
			r_fovy = atan(tan(DEG2RAD(r_refdef.fov_y) / 2) * (1.03 - sin(cl.time * 1.5) * 0.03)) * 2 / PI_DIV_180;
		}
	}
	//johnfitz

	R_SetFrustum(r_fovx, r_fovy);  //johnfitz -- use r_fov* vars

	R_MarkSurfaces();  //johnfitz -- create texture chains from PVS

	R_CullSurfaces();  //johnfitz -- do after R_SetFrustum and R_MarkSurfaces

	R_UpdateWarpTextures();  //johnfitz -- do this before R_Clear

	R_Clear();

	//johnfitz -- cheat-protect some draw modes
	r_drawflat_cheatsafe = r_fullbright_cheatsafe = r_lightmap_cheatsafe = false;
	r_drawworld_cheatsafe = true;
	if(cl.maxclients == 1)
	{
		if(!r_drawworld.value) r_drawworld_cheatsafe = false;

		if(r_drawflat.value) r_drawflat_cheatsafe = true;
		else if(r_fullbright.value || !cl.worldmodel->lightdata) r_fullbright_cheatsafe = true;
		else if(r_lightmap.value) r_lightmap_cheatsafe = true;
	}
	//johnfitz
}

//==============================================================================
//
// RENDER VIEW
//
//==============================================================================

/*
=============
R_DrawEntitiesOnList
=============
*/
void R_DrawEntitiesOnList(bool alphapass)  //johnfitz -- added parameter
{
	int32_t         i;

	if(!r_drawentities.value)
		return;

	//johnfitz -- sprites are not a special case
	for(i = 0 ; i < cl_numvisedicts ; i++)
	{
		currententity = cl_visedicts[i];

		//johnfitz -- if alphapass is true, draw only alpha entites this time
		//if alphapass is false, draw only nonalpha entities this time
		if((ENTALPHA_DECODE(currententity->alpha) < 1 && !alphapass) ||
		                (ENTALPHA_DECODE(currententity->alpha) == 1 && alphapass))
			continue;

		//johnfitz -- chasecam
		if(currententity == &cl_entities[cl.viewentity])
			currententity->angles[0] *= 0.3;
		//johnfitz

		switch(currententity->model->type)
		{
		case mod_alias:
			R_DrawAliasModel(currententity);
			break;
		case mod_brush:
			R_DrawBrushModel(currententity);
			break;
		case mod_sprite:
			R_DrawSpriteModel(currententity);
			break;
		}
	}
}

/*
=============
R_DrawViewModel -- johnfitz -- gutted
=============
*/
void R_DrawViewModel(void)
{
	if(!r_drawviewmodel.value || !r_drawentities.value || chase_active.value)
		return;

	if(cl.items & IT_INVISIBILITY || cl.stats[STAT_HEALTH] <= 0)
		return;

	currententity = &cl.viewent;
	if(!currententity->model)
		return;

	//johnfitz -- this fixes a crash
	if(currententity->model->type != mod_alias)
		return;
	//johnfitz

	// hack the depth range to prevent view model from poking into walls
	glDepthRange(0, 0.3);
	R_DrawAliasModel(currententity);
	glDepthRange(0, 1);
}

/*
================
R_EmitWirePoint -- johnfitz -- draws a wireframe cross shape for point entities
================
*/
void R_EmitWirePoint(vec3_t origin)
{
	int32_t size = 8;

	glBegin(GL_LINES);
	glVertex3f(origin[0] - size, origin[1], origin[2]);
	glVertex3f(origin[0] + size, origin[1], origin[2]);
	glVertex3f(origin[0], origin[1] - size, origin[2]);
	glVertex3f(origin[0], origin[1] + size, origin[2]);
	glVertex3f(origin[0], origin[1], origin[2] - size);
	glVertex3f(origin[0], origin[1], origin[2] + size);
	glEnd();
}

/*
================
R_EmitWireBox -- johnfitz -- draws one axis aligned bounding box
================
*/
void R_EmitWireBox(vec3_t mins, vec3_t maxs)
{
	glBegin(GL_QUAD_STRIP);
	glVertex3f(mins[0], mins[1], mins[2]);
	glVertex3f(mins[0], mins[1], maxs[2]);
	glVertex3f(maxs[0], mins[1], mins[2]);
	glVertex3f(maxs[0], mins[1], maxs[2]);
	glVertex3f(maxs[0], maxs[1], mins[2]);
	glVertex3f(maxs[0], maxs[1], maxs[2]);
	glVertex3f(mins[0], maxs[1], mins[2]);
	glVertex3f(mins[0], maxs[1], maxs[2]);
	glVertex3f(mins[0], mins[1], mins[2]);
	glVertex3f(mins[0], mins[1], maxs[2]);
	glEnd();
}

/*
================
R_ShowBoundingBoxes -- johnfitz

draw bounding boxes -- the server-side boxes, not the renderer cullboxes
================
*/
void R_ShowBoundingBoxes(void)
{
	extern          edict_t *sv_player;
	vec3_t          mins, maxs;
	edict_t         *ed;
	int32_t                 i;

	if(!r_showbboxes.value || cl.maxclients > 1 || !r_drawentities.value || !sv.active)
		return;

	glDisable(GL_DEPTH_TEST);
	glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
	GL_PolygonOffset(OFFSET_SHOWTRIS);
	glDisable(GL_TEXTURE_2D);
	glDisable(GL_CULL_FACE);
	glColor3f(1, 1, 1);

	for(i = 0, ed = NextEdict(sv.edicts) ; i < sv.num_edicts ; i++, ed = NextEdict(ed))
	{
		if(ed == sv_player)
			continue; //don't draw player's own bbox

//		if (r_showbboxes.value != 2)
//			if (!SV_VisibleToClient (sv_player, ed, sv.worldmodel))
//				continue; //don't draw if not in pvs

		if(ED_Vector(ed, ED_mins)[0] == ED_Vector(ed, ED_maxs)[0] && ED_Vector(ed, ED_mins)[1] == ED_Vector(ed, ED_maxs)[1] && ED_Vector(ed, ED_mins)[2] == ED_Vector(ed, ED_maxs)[2])
		{
			//point entity
			R_EmitWirePoint(ED_Vector(ed, ED_origin));
		}
		else
		{
			//box entity
			VectorAdd(ED_Vector(ed, ED_mins), ED_Vector(ed, ED_origin), mins);
			VectorAdd(ED_Vector(ed, ED_maxs), ED_Vector(ed, ED_origin), maxs);
			R_EmitWireBox(mins, maxs);
		}
	}

	glColor3f(1, 1, 1);
	glEnable(GL_TEXTURE_2D);
	glEnable(GL_CULL_FACE);
	glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
	GL_PolygonOffset(OFFSET_NONE);
	glEnable(GL_DEPTH_TEST);

	Sbar_Changed();  //so we don't get dots collecting on the statusbar
}

/*
================
R_ShowTris -- johnfitz
================
*/
void R_ShowTris(void)
{
	extern cvar_t r_particles;
	int32_t i;

	if(r_showtris.value < 1 || r_showtris.value > 2 || cl.maxclients > 1)
		return;

	if(r_showtris.value == 1)
		glDisable(GL_DEPTH_TEST);
	glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
	GL_PolygonOffset(OFFSET_SHOWTRIS);
	glDisable(GL_TEXTURE_2D);
	glColor3f(1, 1, 1);
//	glEnable (GL_BLEND);
//	glBlendFunc (GL_ONE, GL_ONE);

	if(r_drawworld.value)
	{
		R_DrawWorld_ShowTris();
	}

	if(r_drawentities.value)
	{
		for(i = 0 ; i < cl_numvisedicts ; i++)
		{
			currententity = cl_visedicts[i];

			if(currententity == &cl_entities[cl.viewentity])  // chasecam
				currententity->angles[0] *= 0.3;

			switch(currententity->model->type)
			{
			case mod_brush:
				R_DrawBrushModel_ShowTris(currententity);
				break;
			case mod_alias:
				R_DrawAliasModel_ShowTris(currententity);
				break;
			case mod_sprite:
				R_DrawSpriteModel(currententity);
				break;
			default:
				break;
			}
		}

		// viewmodel
		currententity = &cl.viewent;
		if(r_drawviewmodel.value
		                && !chase_active.value
		                && cl.stats[STAT_HEALTH] > 0
		                && !(cl.items & IT_INVISIBILITY)
		                && currententity->model
		                && currententity->model->type == mod_alias)
		{
			glDepthRange(0, 0.3);
			R_DrawAliasModel_ShowTris(currententity);
			glDepthRange(0, 1);
		}
	}

	if(r_particles.value)
	{
		R_DrawParticles_ShowTris();
	}

//	glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
//	glDisable (GL_BLEND);
	glColor3f(1, 1, 1);
	glEnable(GL_TEXTURE_2D);
	glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
	GL_PolygonOffset(OFFSET_NONE);
	if(r_showtris.value == 1)
		glEnable(GL_DEPTH_TEST);

	Sbar_Changed();  //so we don't get dots collecting on the statusbar
}

/*
================
R_DrawShadows
================
*/
void R_DrawShadows(void)
{
	int32_t i;

	if(!r_shadows.value || !r_drawentities.value || r_drawflat_cheatsafe || r_lightmap_cheatsafe)
		return;

	// Use stencil buffer to prevent self-intersecting shadows, from Baker (MarkV)
	if(gl_stencilbits)
	{
		glClear(GL_STENCIL_BUFFER_BIT);
		glStencilFunc(GL_EQUAL, 0, ~0);
		glStencilOp(GL_KEEP, GL_KEEP, GL_INCR);
		glEnable(GL_STENCIL_TEST);
	}

	for(i = 0 ; i < cl_numvisedicts ; i++)
	{
		currententity = cl_visedicts[i];

		if(currententity->model->type != mod_alias)
			continue;

		if(currententity == &cl.viewent)
			return;

		GL_DrawAliasShadow(currententity);
	}

	if(gl_stencilbits)
	{
		glDisable(GL_STENCIL_TEST);
	}
}

/*
================
R_RenderScene
================
*/
void R_RenderScene(void)
{
	R_SetupScene();  //johnfitz -- this does everything that should be done once per call to RenderScene

	Fog_EnableGFog();  //johnfitz

	Sky_DrawSky();  //johnfitz

	R_DrawWorld();

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

	R_DrawShadows();  //johnfitz -- render entity shadows

	R_DrawEntitiesOnList(false);  //johnfitz -- false means this is the pass for nonalpha entities

	R_DrawWorld_Water();  //johnfitz -- drawn here since they might have transparency

	R_DrawEntitiesOnList(true);  //johnfitz -- true means this is the pass for alpha entities

	R_RenderDlights();  //triangle fan dlights -- johnfitz -- moved after water

	R_DrawParticles();

	Fog_DisableGFog();  //johnfitz

	R_DrawViewModel();  //johnfitz -- moved here from R_RenderView

	R_ShowTris();  //johnfitz

	R_ShowBoundingBoxes();  //johnfitz
}

static GLuint r_scaleview_texture;
static int32_t r_scaleview_texture_width, r_scaleview_texture_height;

/*
=============
R_ScaleView_DeleteTexture
=============
*/
void R_ScaleView_DeleteTexture(void)
{
	glDeleteTextures(1, &r_scaleview_texture);
	r_scaleview_texture = 0;
}

/*
================
R_ScaleView

The r_scale cvar allows rendering the 3D view at 1/2, 1/3, or 1/4 resolution.
This function scales the reduced resolution 3D view back up to fill
r_refdef.vrect. This is for emulating a low-resolution pixellated look,
or possibly as a perforance boost on slow graphics cards.
================
*/
void R_ScaleView(void)
{
	float smax, tmax;
	int32_t scale;
	int32_t srcx, srcy, srcw, srch;

	// copied from R_SetupGL()
	scale = CLAMP(1, (int32_t)r_scale.value, 4);
	srcx = glx + r_refdef.vrect.x;
	srcy = gly + glheight - r_refdef.vrect.y - r_refdef.vrect.height;
	srcw = r_refdef.vrect.width / scale;
	srch = r_refdef.vrect.height / scale;

	if(scale == 1)
		return;

	// make sure texture unit 0 is selected
	GL_DisableMultitexture();

	// create (if needed) and bind the render-to-texture texture
	if(!r_scaleview_texture)
	{
		glGenTextures(1, &r_scaleview_texture);

		r_scaleview_texture_width = 0;
		r_scaleview_texture_height = 0;
	}
	glBindTexture(GL_TEXTURE_2D, r_scaleview_texture);

	// resize render-to-texture texture if needed
	if(r_scaleview_texture_width < srcw
	                || r_scaleview_texture_height < srch)
	{
		r_scaleview_texture_width = srcw;
		r_scaleview_texture_height = srch;

		if(!gl_texture_NPOT)
		{
			r_scaleview_texture_width = TexMgr_Pad(r_scaleview_texture_width);
			r_scaleview_texture_height = TexMgr_Pad(r_scaleview_texture_height);
		}

		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, r_scaleview_texture_width, r_scaleview_texture_height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
	}

	// copy the framebuffer to the texture
	glBindTexture(GL_TEXTURE_2D, r_scaleview_texture);
	glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, srcx, srcy, srcw, srch);

	// draw the texture back to the framebuffer
	glDisable(GL_ALPHA_TEST);
	glDisable(GL_DEPTH_TEST);
	glDisable(GL_CULL_FACE);
	glDisable(GL_BLEND);

	glViewport(srcx, srcy, r_refdef.vrect.width, r_refdef.vrect.height);

	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();

	// correction factor if we lack NPOT textures, normally these are 1.0f
	smax = srcw / (float)r_scaleview_texture_width;
	tmax = srch / (float)r_scaleview_texture_height;

	glBegin(GL_QUADS);
	glTexCoord2f(0, 0);
	glVertex2f(-1, -1);
	glTexCoord2f(smax, 0);
	glVertex2f(1, -1);
	glTexCoord2f(smax, tmax);
	glVertex2f(1, 1);
	glTexCoord2f(0, tmax);
	glVertex2f(-1, 1);
	glEnd();

	// clear cached binding
	GL_ClearBindings();
}

/*
================
R_RenderView
================
*/
void R_RenderView(void)
{
	double  time1, time2;

	if(r_norefresh.value)
		return;

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

	time1 = 0; /* avoid compiler warning */
	if(r_speeds.value)
	{
		glFinish();
		time1 = Sys_DoubleTime();

		//johnfitz -- rendering statistics
		rs_brushpolys = rs_aliaspolys = rs_skypolys = rs_particles = rs_fogpolys = rs_megatexels =
		                                        rs_dynamiclightmaps = rs_aliaspasses = rs_skypasses = rs_brushpasses = 0;
	}
	else if(gl_finish.value)
		glFinish();

	R_SetupView();  //johnfitz -- this does everything that should be done once per frame

	//johnfitz -- stereo rendering -- full of hacky goodness
	if(r_stereo.value)
	{
		float eyesep = CLAMP(-8.0f, r_stereo.value, 8.0f);
		float fdepth = CLAMP(32.0f, r_stereodepth.value, 1024.0f);

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

		//render left eye (red)
		glColorMask(1, 0, 0, 1);
		VectorMA(r_refdef.vieworg, -0.5f * eyesep, vright, r_refdef.vieworg);
		frustum_skew = 0.5 * eyesep * NEARCLIP / fdepth;
		srand((int32_t)(cl.time * 1000));  //sync random stuff between eyes

		R_RenderScene();

		//render right eye (cyan)
		glClear(GL_DEPTH_BUFFER_BIT);
		glColorMask(0, 1, 1, 1);
		VectorMA(r_refdef.vieworg, 1.0f * eyesep, vright, r_refdef.vieworg);
		frustum_skew = -frustum_skew;
		srand((int32_t)(cl.time * 1000));  //sync random stuff between eyes

		R_RenderScene();

		//restore
		glColorMask(1, 1, 1, 1);
		VectorMA(r_refdef.vieworg, -0.5f * eyesep, vright, r_refdef.vieworg);
		frustum_skew = 0.0f;
	}
	else
	{
		R_RenderScene();
	}
	//johnfitz

	R_ScaleView();

	//johnfitz -- modified r_speeds output
	time2 = Sys_DoubleTime();
	if(r_pos.value)
		Con_Printf("x %" PRIi32 " y %" PRIi32 " z %" PRIi32 " (pitch %" PRIi32 " yaw %" PRIi32 " roll %" PRIi32 ")\n",
		           (int32_t)cl_entities[cl.viewentity].origin[0],
		           (int32_t)cl_entities[cl.viewentity].origin[1],
		           (int32_t)cl_entities[cl.viewentity].origin[2],
		           (int32_t)cl.viewangles[PITCH],
		           (int32_t)cl.viewangles[YAW],
		           (int32_t)cl.viewangles[ROLL]);
	else if(r_speeds.value == 2)
		Con_Printf("%3" PRIi32 " ms  %4" PRIi32 "/%4" PRIi32 " wpoly %4" PRIi32 "/%4" PRIi32 " epoly %3" PRIi32 " lmap %4" PRIi32 "%4" PRIi32 "sky %1.1f mtex\n",
		           (int32_t)((time2 - time1) * 1000),
		           rs_brushpolys,
		           rs_brushpasses,
		           rs_aliaspolys,
		           rs_aliaspasses,
		           rs_dynamiclightmaps,
		           rs_skypolys,
		           rs_skypasses,
		           TexMgr_FrameUsage());
	else if(r_speeds.value)
		Con_Printf("%3" PRIi32 " ms  %4" PRIi32 " wpoly %4" PRIi32 " epoly %3" PRIi32 " lmap\n",
		           (int32_t)((time2 - time1) * 1000),
		           rs_brushpolys,
		           rs_aliaspolys,
		           rs_dynamiclightmaps);
	//johnfitz
}