/*
 * 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.
 *
 * =======================================================================
 *
 * Refresher setup and main part of the frame generation
 *
 * =======================================================================
 */

#include "header/local.h"

#define NUM_BEAM_SEGS 6

void R_Clear ( void );
void R_BeginRegistration ( char *map );
struct model_s  *R_RegisterModel ( char *name );
struct image_s  *R_RegisterSkin ( char *name );
void R_SetSky ( char *name, float rotate, vec3_t axis );
void R_EndRegistration ( void );
void R_RenderFrame ( refdef_t *fd );
struct image_s *Draw_FindPic ( char *name );

void    Draw_Pic ( int x, int y, char *name );
void    Draw_Char ( int x, int y, int c );
void    Draw_TileClear ( int x, int y, int w, int h, char *name );
void    Draw_Fill ( int x, int y, int w, int h, int c );
void    Draw_FadeScreen ( void );

viddef_t vid;

refimport_t ri;

int QGL_TEXTURE0, QGL_TEXTURE1;

model_t     *r_worldmodel;

float gldepthmin, gldepthmax;

glconfig_t gl_config;
glstate_t gl_state;

image_t     *r_notexture;       /* use for bad textures */
image_t     *r_particletexture; /* little dot for particles */

entity_t    *currententity;
model_t     *currentmodel;

cplane_t frustum [ 4 ];

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;

float v_blend [ 4 ];            /* final blending color */

void R_Strings ( void );

/* 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_newrefdef;

int r_viewcluster, r_viewcluster2, r_oldviewcluster, r_oldviewcluster2;
extern qboolean have_stencil;
unsigned r_rawpalette [ 256 ];

cvar_t  *gl_norefresh;
cvar_t  *gl_drawentities;
cvar_t  *gl_drawworld;
cvar_t  *gl_speeds;
cvar_t  *gl_fullbright;
cvar_t  *gl_novis;
cvar_t  *gl_nocull;
cvar_t  *gl_lerpmodels;
cvar_t  *gl_lefthand;
cvar_t  *gl_farsee;

cvar_t  *gl_lightlevel;
cvar_t  *gl_overbrightbits;

cvar_t  *gl_nosubimage;
cvar_t  *gl_allow_software;

cvar_t  *gl_vertex_arrays;

cvar_t  *gl_particle_min_size;
cvar_t  *gl_particle_max_size;
cvar_t  *gl_particle_size;
cvar_t  *gl_particle_att_a;
cvar_t  *gl_particle_att_b;
cvar_t  *gl_particle_att_c;

cvar_t  *gl_ext_swapinterval;
cvar_t  *gl_ext_palettedtexture;
cvar_t  *gl_ext_multitexture;
cvar_t  *gl_ext_pointparameters;
cvar_t  *gl_ext_compiled_vertex_array;
cvar_t  *gl_ext_mtexcombine;

cvar_t  *gl_log;
cvar_t  *gl_bitdepth;
cvar_t  *gl_drawbuffer;
cvar_t  *gl_driver;
cvar_t  *gl_lightmap;
cvar_t  *gl_shadows;
cvar_t  *gl_stencilshadow;
cvar_t  *gl_mode;

cvar_t  *gl_customwidth;
cvar_t  *gl_customheight;

cvar_t  *gl_dynamic;
cvar_t  *gl_modulate;
cvar_t  *gl_nobind;
cvar_t  *gl_round_down;
cvar_t  *gl_picmip;
cvar_t  *gl_skymip;
cvar_t  *gl_showtris;
cvar_t  *gl_ztrick;
cvar_t  *gl_finish;
cvar_t  *gl_clear;
cvar_t  *gl_cull;
cvar_t  *gl_polyblend;
cvar_t  *gl_flashblend;
cvar_t  *gl_playermip;
cvar_t  *gl_saturatelighting;
cvar_t  *gl_swapinterval;
cvar_t  *gl_texturemode;
cvar_t  *gl_texturealphamode;
cvar_t  *gl_texturesolidmode;
cvar_t	*gl_anisotropic;
cvar_t	*gl_anisotropic_avail;
cvar_t  *gl_lockpvs;

cvar_t  *vid_fullscreen;
cvar_t  *vid_gamma;
cvar_t  *vid_ref;

/*
 * Returns true if the box is completely outside the frustom
 */
qboolean
R_CullBox ( vec3_t mins, vec3_t maxs )
{
	int i;

	if ( gl_nocull->value )
	{
		return ( false );
	}

	for ( i = 0; i < 4; i++ )
	{
		if ( BOX_ON_PLANE_SIDE( mins, maxs, &frustum [ i ] ) == 2 )
		{
			return ( true );
		}
	}

	return ( false );
}

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

	qglRotatef( e->angles [ 1 ],  0, 0, 1 );
	qglRotatef( -e->angles [ 0 ],  0, 1, 0 );
	qglRotatef( -e->angles [ 2 ],  1, 0, 0 );
}

void
R_DrawSpriteModel ( entity_t *e )
{
	float alpha = 1.0F;
	vec3_t point;
	dsprframe_t *frame;
	float       *up, *right;
	dsprite_t       *psprite;

	/* don't even bother culling, because it's just a single
	 * polygon without a surface cache */
	psprite = (dsprite_t *) currentmodel->extradata;

	e->frame %= psprite->numframes;

	frame = &psprite->frames [ e->frame ];

	{
		/* normal sprite */
		up = vup;
		right = vright;
	}

	if ( e->flags & RF_TRANSLUCENT )
	{
		alpha = e->alpha;
	}

	if ( alpha != 1.0F )
	{
		qglEnable( GL_BLEND );
	}

	qglColor4f( 1, 1, 1, alpha );

	R_Bind( currentmodel->skins [ e->frame ]->texnum );

	R_TexEnv( GL_MODULATE );

	if ( alpha == 1.0 )
	{
		qglEnable( GL_ALPHA_TEST );
	}
	else
	{
		qglDisable( GL_ALPHA_TEST );
	}

	qglBegin( GL_QUADS );

	qglTexCoord2f( 0, 1 );
	VectorMA( e->origin, -frame->origin_y, up, point );
	VectorMA( point, -frame->origin_x, right, point );
	qglVertex3fv( point );

	qglTexCoord2f( 0, 0 );
	VectorMA( e->origin, frame->height - frame->origin_y, up, point );
	VectorMA( point, -frame->origin_x, right, point );
	qglVertex3fv( point );

	qglTexCoord2f( 1, 0 );
	VectorMA( e->origin, frame->height - frame->origin_y, up, point );
	VectorMA( point, frame->width - frame->origin_x, right, point );
	qglVertex3fv( point );

	qglTexCoord2f( 1, 1 );
	VectorMA( e->origin, -frame->origin_y, up, point );
	VectorMA( point, frame->width - frame->origin_x, right, point );
	qglVertex3fv( point );

	qglEnd();

	qglDisable( GL_ALPHA_TEST );
	R_TexEnv( GL_REPLACE );

	if ( alpha != 1.0F )
	{
		qglDisable( GL_BLEND );
	}

	qglColor4f( 1, 1, 1, 1 );
}

void
R_DrawNullModel ( void )
{
	vec3_t shadelight;
	int i;

	if ( currententity->flags & RF_FULLBRIGHT )
	{
		shadelight [ 0 ] = shadelight [ 1 ] = shadelight [ 2 ] = 1.0F;
	}
	else
	{
		R_LightPoint( currententity->origin, shadelight );
	}

	qglPushMatrix();
	R_RotateForEntity( currententity );

	qglDisable( GL_TEXTURE_2D );
	qglColor3fv( shadelight );

	qglBegin( GL_TRIANGLE_FAN );
	qglVertex3f( 0, 0, -16 );

	for ( i = 0; i <= 4; i++ )
	{
		qglVertex3f( 16 * cos( i * M_PI / 2 ), 16 * sin( i * M_PI / 2 ), 0 );
	}

	qglEnd();

	qglBegin( GL_TRIANGLE_FAN );
	qglVertex3f( 0, 0, 16 );

	for ( i = 4; i >= 0; i-- )
	{
		qglVertex3f( 16 * cos( i * M_PI / 2 ), 16 * sin( i * M_PI / 2 ), 0 );
	}

	qglEnd();

	qglColor3f( 1, 1, 1 );
	qglPopMatrix();
	qglEnable( GL_TEXTURE_2D );
}

void
R_DrawEntitiesOnList ( void )
{
	int i;

	if ( !gl_drawentities->value )
	{
		return;
	}

	/* draw non-transparent first */
	for ( i = 0; i < r_newrefdef.num_entities; i++ )
	{
		currententity = &r_newrefdef.entities [ i ];

		if ( currententity->flags & RF_TRANSLUCENT )
		{
			continue; /* solid */
		}

		if ( currententity->flags & RF_BEAM )
		{
			R_DrawBeam( currententity );
		}
		else
		{
			currentmodel = currententity->model;

			if ( !currentmodel )
			{
				R_DrawNullModel();
				continue;
			}

			switch ( currentmodel->type )
			{
				case mod_alias:
					R_DrawAliasModel( currententity );
					break;
				case mod_brush:
					R_DrawBrushModel( currententity );
					break;
				case mod_sprite:
					R_DrawSpriteModel( currententity );
					break;
				default:
					ri.Sys_Error( ERR_DROP, "Bad modeltype" );
					break;
			}
		}
	}

	/* draw transparent entities
	 * we could sort these if it ever
	 * becomes a problem... */
	qglDepthMask( 0 ); /* no z writes */

	for ( i = 0; i < r_newrefdef.num_entities; i++ )
	{
		currententity = &r_newrefdef.entities [ i ];

		if ( !( currententity->flags & RF_TRANSLUCENT ) )
		{
			continue; /* solid */
		}

		if ( currententity->flags & RF_BEAM )
		{
			R_DrawBeam( currententity );
		}
		else
		{
			currentmodel = currententity->model;

			if ( !currentmodel )
			{
				R_DrawNullModel();
				continue;
			}

			switch ( currentmodel->type )
			{
				case mod_alias:
					R_DrawAliasModel( currententity );
					break;
				case mod_brush:
					R_DrawBrushModel( currententity );
					break;
				case mod_sprite:
					R_DrawSpriteModel( currententity );
					break;
				default:
					ri.Sys_Error( ERR_DROP, "Bad modeltype" );
					break;
			}
		}
	}

	qglDepthMask( 1 ); /* back to writing */
}

void
R_DrawParticles2 ( int num_particles, const particle_t particles[], const unsigned colortable [ 768 ] )
{
	const particle_t *p;
	int i;
	vec3_t up, right;
	float scale;
	byte color [ 4 ];

	R_Bind( r_particletexture->texnum );
	qglDepthMask( GL_FALSE ); /* no z buffering */
	qglEnable( GL_BLEND );
	R_TexEnv( GL_MODULATE );
	qglBegin( GL_TRIANGLES );

	VectorScale( vup, 1.5, up );
	VectorScale( vright, 1.5, right );

	for ( p = particles, i = 0; i < num_particles; i++, p++ )
	{
		/* hack a scale up to keep particles from disapearing */
		scale = ( p->origin [ 0 ] - r_origin [ 0 ] ) * vpn [ 0 ] +
				( p->origin [ 1 ] - r_origin [ 1 ] ) * vpn [ 1 ] +
				( p->origin [ 2 ] - r_origin [ 2 ] ) * vpn [ 2 ];

		if ( scale < 20 )
		{
			scale = 1;
		}
		else
		{
			scale = 1 + scale * 0.004;
		}

		*(int *) color = colortable [ p->color ];
		color [ 3 ] = p->alpha * 255;

		qglColor4ubv( color );

		qglTexCoord2f( 0.0625, 0.0625 );
		qglVertex3fv( p->origin );

		qglTexCoord2f( 1.0625, 0.0625 );
		qglVertex3f( p->origin [ 0 ] + up [ 0 ] * scale,
				p->origin [ 1 ] + up [ 1 ] * scale,
				p->origin [ 2 ] + up [ 2 ] * scale );

		qglTexCoord2f( 0.0625, 1.0625 );
		qglVertex3f( p->origin [ 0 ] + right [ 0 ] * scale,
				p->origin [ 1 ] + right [ 1 ] * scale,
				p->origin [ 2 ] + right [ 2 ] * scale );
	}

	qglEnd();
	qglDisable( GL_BLEND );
	qglColor4f( 1, 1, 1, 1 );
	qglDepthMask( 1 ); /* back to normal Z buffering */
	R_TexEnv( GL_REPLACE );
}

void
R_DrawParticles ( void )
{
	if ( gl_ext_pointparameters->value && qglPointParameterfEXT )
	{
		int i;
		unsigned char color [ 4 ];
		const particle_t *p;

		qglDepthMask( GL_FALSE );
		qglEnable( GL_BLEND );
		qglDisable( GL_TEXTURE_2D );

		qglPointSize( gl_particle_size->value );

		qglBegin( GL_POINTS );

		for ( i = 0, p = r_newrefdef.particles; i < r_newrefdef.num_particles; i++, p++ )
		{
			*(int *) color = d_8to24table [ p->color & 0xFF ];
			color [ 3 ] = p->alpha * 255;
			qglColor4ubv( color );
			qglVertex3fv( p->origin );
		}

		qglEnd();

		qglDisable( GL_BLEND );
		qglColor4f( 1.0F, 1.0F, 1.0F, 1.0F );
		qglDepthMask( GL_TRUE );
		qglEnable( GL_TEXTURE_2D );
	}
	else
	{
		R_DrawParticles2( r_newrefdef.num_particles, r_newrefdef.particles, d_8to24table );
	}
}

void
R_PolyBlend ( void )
{
	if ( !gl_polyblend->value )
	{
		return;
	}

	if ( !v_blend [ 3 ] )
	{
		return;
	}

	qglDisable( GL_ALPHA_TEST );
	qglEnable( GL_BLEND );
	qglDisable( GL_DEPTH_TEST );
	qglDisable( GL_TEXTURE_2D );

	qglLoadIdentity();

	qglRotatef( -90,  1, 0, 0 ); /* put Z going up */
	qglRotatef( 90,  0, 0, 1 ); /* put Z going up */

	qglColor4fv( v_blend );

	qglBegin( GL_QUADS );

	qglVertex3f( 10, 100, 100 );
	qglVertex3f( 10, -100, 100 );
	qglVertex3f( 10, -100, -100 );
	qglVertex3f( 10, 100, -100 );
	qglEnd();

	qglDisable( GL_BLEND );
	qglEnable( GL_TEXTURE_2D );
	qglEnable( GL_ALPHA_TEST );

	qglColor4f( 1, 1, 1, 1 );
}

int
R_SignbitsForPlane ( cplane_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 );
}

void
R_SetFrustum ( void )
{
	int i;

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

void
R_SetupFrame ( void )
{
	int i;
	mleaf_t *leaf;

	r_framecount++;

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

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

	/* current viewcluster */
	if ( !( r_newrefdef.rdflags & RDF_NOWORLDMODEL ) )
	{
		r_oldviewcluster = r_viewcluster;
		r_oldviewcluster2 = r_viewcluster2;
		leaf = Mod_PointInLeaf( r_origin, r_worldmodel );
		r_viewcluster = r_viewcluster2 = leaf->cluster;

		/* check above and below so crossing solid water doesn't draw wrong */
		if ( !leaf->contents )
		{   /* look down a bit */
			vec3_t temp;

			VectorCopy( r_origin, temp );
			temp [ 2 ] -= 16;
			leaf = Mod_PointInLeaf( temp, r_worldmodel );

			if ( !( leaf->contents & CONTENTS_SOLID ) &&
				 ( leaf->cluster != r_viewcluster2 ) )
			{
				r_viewcluster2 = leaf->cluster;
			}
		}
		else
		{
			/* look up a bit */
			vec3_t temp;

			VectorCopy( r_origin, temp );
			temp [ 2 ] += 16;
			leaf = Mod_PointInLeaf( temp, r_worldmodel );

			if ( !( leaf->contents & CONTENTS_SOLID ) &&
				 ( leaf->cluster != r_viewcluster2 ) )
			{
				r_viewcluster2 = leaf->cluster;
			}
		}
	}

	for ( i = 0; i < 4; i++ )
	{
		v_blend [ i ] = r_newrefdef.blend [ i ];
	}

	c_brush_polys = 0;
	c_alias_polys = 0;

	/* clear out the portion of the screen that the NOWORLDMODEL defines */
	if ( r_newrefdef.rdflags & RDF_NOWORLDMODEL )
	{
		qglEnable( GL_SCISSOR_TEST );
		qglClearColor( 0.3, 0.3, 0.3, 1 );
		qglScissor( r_newrefdef.x, vid.height - r_newrefdef.height - r_newrefdef.y, r_newrefdef.width, r_newrefdef.height );
		qglClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
		qglClearColor( 1, 0, 0.5, 0.5 );
		qglDisable( GL_SCISSOR_TEST );
	}
}

void
R_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;

	xmin += -( 2 * gl_state.camera_separation ) / zNear;
	xmax += -( 2 * gl_state.camera_separation ) / zNear;

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

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

	/* set up viewport */
	x = floor( r_newrefdef.x * vid.width / vid.width );
	x2 = ceil( ( r_newrefdef.x + r_newrefdef.width ) * vid.width / vid.width );
	y = floor( vid.height - r_newrefdef.y * vid.height / vid.height );
	y2 = ceil( vid.height - ( r_newrefdef.y + r_newrefdef.height ) * vid.height / vid.height );

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

	qglViewport( x, y2, w, h );

	/* set up projection matrix */
	screenaspect = (float) r_newrefdef.width / r_newrefdef.height;
	qglMatrixMode( GL_PROJECTION );
	qglLoadIdentity();
	if (gl_farsee->value == 0) {
		R_MYgluPerspective( r_newrefdef.fov_y,  screenaspect,  4,  4096 );
	} else {
		R_MYgluPerspective( r_newrefdef.fov_y,  screenaspect,  4,  8192 );
	}

	qglCullFace( GL_FRONT );

	qglMatrixMode( GL_MODELVIEW );
	qglLoadIdentity();

	qglRotatef( -90,  1, 0, 0 ); /* put Z going up */
	qglRotatef( 90,  0, 0, 1 ); /* put Z going up */
	qglRotatef( -r_newrefdef.viewangles [ 2 ],  1, 0, 0 );
	qglRotatef( -r_newrefdef.viewangles [ 0 ],  0, 1, 0 );
	qglRotatef( -r_newrefdef.viewangles [ 1 ],  0, 0, 1 );
	qglTranslatef( -r_newrefdef.vieworg [ 0 ],  -r_newrefdef.vieworg [ 1 ],  -r_newrefdef.vieworg [ 2 ] );

	qglGetFloatv( GL_MODELVIEW_MATRIX, r_world_matrix );

	/* set drawing parms */
	if ( gl_cull->value )
	{
		qglEnable( GL_CULL_FACE );
	}
	else
	{
		qglDisable( GL_CULL_FACE );
	}

	qglDisable( GL_BLEND );
	qglDisable( GL_ALPHA_TEST );
	qglEnable( GL_DEPTH_TEST );
}

void
R_Clear ( void )
{
	if ( gl_ztrick->value )
	{
		static int trickframe;

		if ( gl_clear->value )
		{
			qglClear( GL_COLOR_BUFFER_BIT );
		}

		trickframe++;

		if ( trickframe & 1 )
		{
			gldepthmin = 0;
			gldepthmax = 0.49999;
			qglDepthFunc( GL_LEQUAL );
		}
		else
		{
			gldepthmin = 1;
			gldepthmax = 0.5;
			qglDepthFunc( GL_GEQUAL );
		}
	}
	else
	{
		if ( gl_clear->value )
		{
			qglClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
		}
		else
		{
			qglClear( GL_DEPTH_BUFFER_BIT );
		}

		gldepthmin = 0;
		gldepthmax = 1;
		qglDepthFunc( GL_LEQUAL );
	}

	qglDepthRange( gldepthmin, gldepthmax );

	/* stencilbuffer shadows */
	if ( gl_shadows->value && have_stencil && gl_stencilshadow->value )
	{
		qglClearStencil( 1 );
		qglClear( GL_STENCIL_BUFFER_BIT );
	}
}

void
R_Flash ( void )
{
	R_PolyBlend();
}

/*
 * r_newrefdef must be set before the first call
 */
void
R_RenderView ( refdef_t *fd )
{
	if ( gl_norefresh->value )
	{
		return;
	}

	r_newrefdef = *fd;

	if ( !r_worldmodel && !( r_newrefdef.rdflags & RDF_NOWORLDMODEL ) )
	{
		ri.Sys_Error( ERR_DROP, "R_RenderView: NULL worldmodel" );
	}

	if ( gl_speeds->value )
	{
		c_brush_polys = 0;
		c_alias_polys = 0;
	}

	R_PushDlights();

	if ( gl_finish->value )
	{
		qglFinish();
	}

	R_SetupFrame();

	R_SetFrustum();

	R_SetupGL();

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

	R_DrawWorld();

	R_DrawEntitiesOnList();

	R_RenderDlights();

	R_DrawParticles();

	R_DrawAlphaSurfaces();

	R_Flash();

	if ( gl_speeds->value )
	{
		ri.Con_Printf( PRINT_ALL, "%4i wpoly %4i epoly %i tex %i lmaps\n",
				c_brush_polys,
				c_alias_polys,
				c_visible_textures,
				c_visible_lightmaps );
	}
}

void
R_SetGL2D ( void )
{
	/* set 2D virtual screen size */
	qglViewport( 0, 0, vid.width, vid.height );
	qglMatrixMode( GL_PROJECTION );
	qglLoadIdentity();
	qglOrtho( 0, vid.width, vid.height, 0, -99999, 99999 );
	qglMatrixMode( GL_MODELVIEW );
	qglLoadIdentity();
	qglDisable( GL_DEPTH_TEST );
	qglDisable( GL_CULL_FACE );
	qglDisable( GL_BLEND );
	qglEnable( GL_ALPHA_TEST );
	qglColor4f( 1, 1, 1, 1 );
}

void
R_SetLightLevel ( void )
{
	vec3_t shadelight;

	if ( r_newrefdef.rdflags & RDF_NOWORLDMODEL )
	{
		return;
	}

	/* save off light value for server to look at */
	R_LightPoint( r_newrefdef.vieworg, shadelight );

	/* pick the greatest component, which should be the same
	 * as the mono value returned by software */
	if ( shadelight [ 0 ] > shadelight [ 1 ] )
	{
		if ( shadelight [ 0 ] > shadelight [ 2 ] )
		{
			gl_lightlevel->value = 150 * shadelight [ 0 ];
		}
		else
		{
			gl_lightlevel->value = 150 * shadelight [ 2 ];
		}
	}
	else
	{
		if ( shadelight [ 1 ] > shadelight [ 2 ] )
		{
			gl_lightlevel->value = 150 * shadelight [ 1 ];
		}
		else
		{
			gl_lightlevel->value = 150 * shadelight [ 2 ];
		}
	}
}

void
R_RenderFrame ( refdef_t *fd )
{
	R_RenderView( fd );
	R_SetLightLevel();
	R_SetGL2D();
}

void
R_Register ( void )
{
	gl_lefthand = ri.Cvar_Get( "hand", "0", CVAR_USERINFO | CVAR_ARCHIVE );
	gl_farsee = ri.Cvar_Get( "gl_farsee", "0", CVAR_LATCH | CVAR_ARCHIVE );
	gl_norefresh = ri.Cvar_Get( "gl_norefresh", "0", 0 );
	gl_fullbright = ri.Cvar_Get( "gl_fullbright", "0", 0 );
	gl_drawentities = ri.Cvar_Get( "gl_drawentities", "1", 0 );
	gl_drawworld = ri.Cvar_Get( "gl_drawworld", "1", 0 );
	gl_novis = ri.Cvar_Get( "gl_novis", "0", 0 );
	gl_nocull = ri.Cvar_Get( "gl_nocull", "0", 0 );
	gl_lerpmodels = ri.Cvar_Get( "gl_lerpmodels", "1", 0 );
	gl_speeds = ri.Cvar_Get( "gl_speeds", "0", 0 );

	gl_lightlevel = ri.Cvar_Get( "gl_lightlevel", "0", 0 );
	gl_overbrightbits = ri.Cvar_Get( "gl_overbrightbits", "2", CVAR_ARCHIVE );

	gl_nosubimage = ri.Cvar_Get( "gl_nosubimage", "0", 0 );
	gl_allow_software = ri.Cvar_Get( "gl_allow_software", "0", 0 );

	gl_particle_min_size = ri.Cvar_Get( "gl_particle_min_size", "2", CVAR_ARCHIVE );
	gl_particle_max_size = ri.Cvar_Get( "gl_particle_max_size", "40", CVAR_ARCHIVE );
	gl_particle_size = ri.Cvar_Get( "gl_particle_size", "40", CVAR_ARCHIVE );
	gl_particle_att_a = ri.Cvar_Get( "gl_particle_att_a", "0.01", CVAR_ARCHIVE );
	gl_particle_att_b = ri.Cvar_Get( "gl_particle_att_b", "0.0", CVAR_ARCHIVE );
	gl_particle_att_c = ri.Cvar_Get( "gl_particle_att_c", "0.01", CVAR_ARCHIVE );

	gl_modulate = ri.Cvar_Get( "gl_modulate", "1", CVAR_ARCHIVE );
	gl_log = ri.Cvar_Get( "gl_log", "0", 0 );
	gl_bitdepth = ri.Cvar_Get( "gl_bitdepth", "0", 0 );
	gl_mode = ri.Cvar_Get( "gl_mode", "4", CVAR_ARCHIVE );
	gl_lightmap = ri.Cvar_Get( "gl_lightmap", "0", 0 );
	gl_shadows = ri.Cvar_Get( "gl_shadows", "0", CVAR_ARCHIVE );
	gl_stencilshadow = ri.Cvar_Get( "gl_stencilshadow", "0", CVAR_ARCHIVE );
	gl_dynamic = ri.Cvar_Get( "gl_dynamic", "1", 0 );
	gl_nobind = ri.Cvar_Get( "gl_nobind", "0", 0 );
	gl_round_down = ri.Cvar_Get( "gl_round_down", "1", 0 );
	gl_picmip = ri.Cvar_Get( "gl_picmip", "0", 0 );
	gl_skymip = ri.Cvar_Get( "gl_skymip", "0", 0 );
	gl_showtris = ri.Cvar_Get( "gl_showtris", "0", 0 );
	gl_ztrick = ri.Cvar_Get( "gl_ztrick", "0", 0 );
	gl_finish = ri.Cvar_Get( "gl_finish", "0", CVAR_ARCHIVE );
	gl_clear = ri.Cvar_Get( "gl_clear", "0", 0 );
	gl_cull = ri.Cvar_Get( "gl_cull", "1", 0 );
	gl_polyblend = ri.Cvar_Get( "gl_polyblend", "1", 0 );
	gl_flashblend = ri.Cvar_Get( "gl_flashblend", "0", 0 );
	gl_playermip = ri.Cvar_Get( "gl_playermip", "0", 0 );
	gl_driver = ri.Cvar_Get( "gl_driver", "libGL.so.1", CVAR_ARCHIVE );
	gl_texturemode = ri.Cvar_Get( "gl_texturemode", "GL_LINEAR_MIPMAP_NEAREST", CVAR_ARCHIVE );
	gl_texturealphamode = ri.Cvar_Get( "gl_texturealphamode", "default", CVAR_ARCHIVE );
	gl_texturesolidmode = ri.Cvar_Get( "gl_texturesolidmode", "default", CVAR_ARCHIVE );
	gl_anisotropic = ri.Cvar_Get( "gl_anisotropic", "0", CVAR_ARCHIVE );
	gl_anisotropic_avail = ri.Cvar_Get( "gl_anisotropic_avail", "0", 0 );
	gl_lockpvs = ri.Cvar_Get( "gl_lockpvs", "0", 0 );

	gl_vertex_arrays = ri.Cvar_Get( "gl_vertex_arrays", "0", CVAR_ARCHIVE );

	gl_ext_swapinterval = ri.Cvar_Get( "gl_ext_swapinterval", "1", CVAR_ARCHIVE );
	gl_ext_palettedtexture = ri.Cvar_Get( "gl_ext_palettedtexture", "0", CVAR_ARCHIVE );
	gl_ext_multitexture = ri.Cvar_Get( "gl_ext_multitexture", "1", CVAR_ARCHIVE );
	gl_ext_pointparameters = ri.Cvar_Get( "gl_ext_pointparameters", "1", CVAR_ARCHIVE );
	gl_ext_compiled_vertex_array = ri.Cvar_Get( "gl_ext_compiled_vertex_array", "1", CVAR_ARCHIVE );
	gl_ext_mtexcombine = ri.Cvar_Get( "gl_ext_mtexcombine", "1", CVAR_ARCHIVE );

	gl_drawbuffer = ri.Cvar_Get( "gl_drawbuffer", "GL_BACK", 0 );
	gl_swapinterval = ri.Cvar_Get( "gl_swapinterval", "1", CVAR_ARCHIVE );

	gl_saturatelighting = ri.Cvar_Get( "gl_saturatelighting", "0", 0 );

	vid_fullscreen = ri.Cvar_Get( "vid_fullscreen", "0", CVAR_ARCHIVE );
	vid_gamma = ri.Cvar_Get( "vid_gamma", "1.0", CVAR_ARCHIVE );
	vid_ref = ri.Cvar_Get( "vid_ref", "soft", CVAR_ARCHIVE );

	gl_customwidth = ri.Cvar_Get( "gl_customwidth",  "1024", CVAR_ARCHIVE );
	gl_customheight = ri.Cvar_Get( "gl_customheight", "768", CVAR_ARCHIVE );

	ri.Cmd_AddCommand( "imagelist", R_ImageList_f );
	ri.Cmd_AddCommand( "screenshot", R_ScreenShot );
	ri.Cmd_AddCommand( "modellist", Mod_Modellist_f );
	ri.Cmd_AddCommand( "gl_strings", R_Strings );
}

qboolean
R_SetMode ( void )
{
	rserr_t err;
	qboolean fullscreen;

	fullscreen = vid_fullscreen->value;

	vid_fullscreen->modified = false;
	gl_mode->modified = false;

	/* a bit hackish approach to enable custom resolutions:
	 * Glimp_SetMode needs these values set for mode -1 */
	vid.width = gl_customwidth->value;
	vid.height = gl_customheight->value;

	if ( ( err = GLimp_SetMode( &vid.width, &vid.height, gl_mode->value, fullscreen ) ) == rserr_ok )
	{
		if ( gl_mode->value == -1 )
		{
			gl_state.prev_mode = 3; /* safe default for custom mode */
		}
		else
		{
			gl_state.prev_mode = gl_mode->value;
		}
	}
	else
	{
		if ( err == rserr_invalid_fullscreen )
		{
			ri.Cvar_SetValue( "vid_fullscreen", 0 );
			vid_fullscreen->modified = false;
			ri.Con_Printf( PRINT_ALL, "ref_gl::R_SetMode() - fullscreen unavailable in this mode\n" );

			if ( ( err = GLimp_SetMode( &vid.width, &vid.height, gl_mode->value, false ) ) == rserr_ok )
			{
				return ( true );
			}
		}
		else if ( err == rserr_invalid_mode )
		{
			ri.Cvar_SetValue( "gl_mode", gl_state.prev_mode );
			gl_mode->modified = false;
			ri.Con_Printf( PRINT_ALL, "ref_gl::R_SetMode() - invalid mode\n" );
		}

		/* try setting it back to something safe */
		if ( ( err = GLimp_SetMode( &vid.width, &vid.height, gl_state.prev_mode, false ) ) != rserr_ok )
		{
			ri.Con_Printf( PRINT_ALL, "ref_gl::R_SetMode() - could not revert to safe mode\n" );
			return ( false );
		}
	}

	return ( true );
}

int
R_Init ( void *hinstance, void *hWnd )
{
	char renderer_buffer [ 1000 ];
	char vendor_buffer [ 1000 ];
	int err;
	int j;
	extern float r_turbsin [ 256 ];

	for ( j = 0; j < 256; j++ )
	{
		r_turbsin [ j ] *= 0.5;
	}

	ri.Con_Printf( PRINT_ALL, "Refresh: " REF_VERSION "\n" );

	Draw_GetPalette();

	R_Register();

	/* initialize our QGL dynamic bindings */
	if ( !QGL_Init( gl_driver->string ) )
	{
		QGL_Shutdown();
		ri.Con_Printf( PRINT_ALL, "ref_gl::R_Init() - could not load \"%s\"\n", gl_driver->string );
		return ( -1 );
	}

	/* initialize OS-specific parts of OpenGL */
	if ( !GLimp_Init() )
	{
		QGL_Shutdown();
		return ( -1 );
	}

	/* set our "safe" modes */
	gl_state.prev_mode = 3;

	/* create the window and set up the context */
	if ( !R_SetMode() )
	{
		QGL_Shutdown();
		ri.Con_Printf( PRINT_ALL, "ref_gl::R_Init() - could not R_SetMode()\n" );
		return ( -1 );
	}

	ri.Vid_MenuInit();

	/* get our various GL strings */
	ri.Con_Printf( PRINT_ALL, "\nOpenGL setting:\n", gl_config.vendor_string );
	gl_config.vendor_string = (char *) qglGetString( GL_VENDOR );
	ri.Con_Printf( PRINT_ALL, "GL_VENDOR: %s\n", gl_config.vendor_string );
	gl_config.renderer_string = (char *) qglGetString( GL_RENDERER );
	ri.Con_Printf( PRINT_ALL, "GL_RENDERER: %s\n", gl_config.renderer_string );
	gl_config.version_string = (char *) qglGetString( GL_VERSION );
	ri.Con_Printf( PRINT_ALL, "GL_VERSION: %s\n", gl_config.version_string );
	gl_config.extensions_string = (char *) qglGetString( GL_EXTENSIONS );
	ri.Con_Printf( PRINT_ALL, "GL_EXTENSIONS: %s\n", gl_config.extensions_string );

	strncpy( renderer_buffer, gl_config.renderer_string, sizeof ( renderer_buffer ) );
	renderer_buffer [ sizeof ( renderer_buffer ) - 1 ] = 0;
	strlwr( renderer_buffer );

	strncpy( vendor_buffer, gl_config.vendor_string, sizeof ( vendor_buffer ) );
	vendor_buffer [ sizeof ( vendor_buffer ) - 1 ] = 0;
	strlwr( vendor_buffer );

	ri.Cvar_Set( "scr_drawall", "0" );
	gl_config.allow_cds = true;

	ri.Con_Printf( PRINT_ALL, "\n\nProbing for OpenGL extensions:\n" );

	/* grab extensions */
	if ( strstr( gl_config.extensions_string, "GL_EXT_compiled_vertex_array" ) ||
		 strstr( gl_config.extensions_string, "GL_SGI_compiled_vertex_array" ) )
	{
		ri.Con_Printf( PRINT_ALL, "...enabling GL_EXT_compiled_vertex_array\n" );
		qglLockArraysEXT = (void *) qwglGetProcAddress( "glLockArraysEXT" );
		qglUnlockArraysEXT = (void *) qwglGetProcAddress( "glUnlockArraysEXT" );
	}
	else
	{
		ri.Con_Printf( PRINT_ALL, "...GL_EXT_compiled_vertex_array not found\n" );
	}

	if ( strstr( gl_config.extensions_string, "GL_EXT_point_parameters" ) )
	{
		if ( gl_ext_pointparameters->value )
		{
			qglPointParameterfEXT = ( void (APIENTRY *) ( GLenum, GLfloat ) )qwglGetProcAddress( "glPointParameterfEXT" );
			qglPointParameterfvEXT = ( void (APIENTRY *) ( GLenum, const GLfloat * ) )qwglGetProcAddress( "glPointParameterfvEXT" );
			ri.Con_Printf( PRINT_ALL, "...using GL_EXT_point_parameters\n" );
		}
		else
		{
			ri.Con_Printf( PRINT_ALL, "...ignoring GL_EXT_point_parameters\n" );
		}
	}
	else
	{
		ri.Con_Printf( PRINT_ALL, "...GL_EXT_point_parameters not found\n" );
	}

	if ( !qglColorTableEXT &&
		 strstr( gl_config.extensions_string, "GL_EXT_paletted_texture" ) &&
		 strstr( gl_config.extensions_string, "GL_EXT_shared_texture_palette" ) )
	{
		if ( gl_ext_palettedtexture->value )
		{
			ri.Con_Printf( PRINT_ALL, "...using GL_EXT_shared_texture_palette\n" );
			qglColorTableEXT =
				( void (APIENTRY *) ( GLenum, GLenum, GLsizei, GLenum, GLenum, const GLvoid * ) )qwglGetProcAddress(
						"glColorTableEXT" );
		}
		else
		{
			ri.Con_Printf( PRINT_ALL, "...ignoring GL_EXT_shared_texture_palette\n" );
		}
	}
	else
	{
		ri.Con_Printf( PRINT_ALL, "...GL_EXT_shared_texture_palette not found\n" );
	}

	if ( strstr( gl_config.extensions_string, "GL_ARB_multitexture" ) )
	{
		if ( gl_ext_multitexture->value )
		{
			ri.Con_Printf( PRINT_ALL, "...using GL_ARB_multitexture\n" );
			qglMTexCoord2fSGIS = (void *) qwglGetProcAddress( "glMultiTexCoord2fARB" );
			qglActiveTextureARB = (void *) qwglGetProcAddress( "glActiveTextureARB" );
			qglClientActiveTextureARB = (void *) qwglGetProcAddress( "glClientActiveTextureARB" );
			QGL_TEXTURE0 = GL_TEXTURE0_ARB;
			QGL_TEXTURE1 = GL_TEXTURE1_ARB;
		}
		else
		{
			ri.Con_Printf( PRINT_ALL, "...ignoring GL_ARB_multitexture\n" );
		}
	}
	else
	{
		ri.Con_Printf( PRINT_ALL, "...GL_ARB_multitexture not found\n" );
	}

	if ( strstr( gl_config.extensions_string, "GL_SGIS_multitexture" ) )
	{
		if ( qglActiveTextureARB )
		{
			ri.Con_Printf( PRINT_ALL, "...GL_SGIS_multitexture deprecated in favor of ARB_multitexture\n" );
		}
		else if ( gl_ext_multitexture->value )
		{
			ri.Con_Printf( PRINT_ALL, "...using GL_SGIS_multitexture\n" );
			qglMTexCoord2fSGIS = (void *) qwglGetProcAddress( "glMTexCoord2fSGIS" );
			qglSelectTextureSGIS = (void *) qwglGetProcAddress( "glSelectTextureSGIS" );
			QGL_TEXTURE0 = GL_TEXTURE0_SGIS;
			QGL_TEXTURE1 = GL_TEXTURE1_SGIS;
		}
		else
		{
			ri.Con_Printf( PRINT_ALL, "...ignoring GL_SGIS_multitexture\n" );
		}
	}
	else
	{
		ri.Con_Printf( PRINT_ALL, "...GL_SGIS_multitexture not found\n" );
	}

	gl_config.anisotropic = false;

	if ( strstr(gl_config.extensions_string,"GL_EXT_texture_filter_anisotropic") )
	{
		ri.Con_Printf (PRINT_ALL,"...using GL_EXT_texture_filter_anisotropic\n" );
		gl_config.anisotropic = true;
		qglGetFloatv(GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT, &gl_config.max_anisotropy);
		ri.Cvar_SetValue("gl_anisotropic_avail", gl_config.max_anisotropy);
	}
	else
	{
		ri.Con_Printf (PRINT_ALL,"..GL_EXT_texture_filter_anisotropic not found\n" );
		gl_config.anisotropic = false;
		gl_config.max_anisotropy = 0.0;
		ri.Cvar_SetValue("gl_anisotropic_avail", 0.0);
	} 

	gl_config.mtexcombine = false;

	if ( strstr( gl_config.extensions_string, "GL_ARB_texture_env_combine" ) )
	{
		if ( gl_ext_mtexcombine->value )
		{
			Com_Printf( "...using GL_ARB_texture_env_combine\n" );
			gl_config.mtexcombine = true;
		}
		else
		{
			Com_Printf( "...ignoring GL_ARB_texture_env_combine\n" );
		}
	}
	else
	{
		Com_Printf( "...GL_ARB_texture_env_combine not found\n" );
	}

	if ( !gl_config.mtexcombine )
	{
		if ( strstr( gl_config.extensions_string, "GL_EXT_texture_env_combine" ) )
		{
			if ( gl_ext_mtexcombine->value )
			{
				Com_Printf( "...using GL_EXT_texture_env_combine\n" );
				gl_config.mtexcombine = true;
			}
			else
			{
				Com_Printf( "...ignoring GL_EXT_texture_env_combine\n" );
			}
		}
		else
		{
			Com_Printf( "...GL_EXT_texture_env_combine not found\n" );
		}
	}

	R_SetDefaultState();

	R_InitImages();
	Mod_Init();
	R_InitParticleTexture();
	Draw_InitLocal();

	err = qglGetError();

	if ( err != GL_NO_ERROR )
	{
		ri.Con_Printf( PRINT_ALL, "glGetError() = 0x%x\n", err );
	}

	return ( true );
}

void
R_Shutdown ( void )
{
	ri.Cmd_RemoveCommand( "modellist" );
	ri.Cmd_RemoveCommand( "screenshot" );
	ri.Cmd_RemoveCommand( "imagelist" );
	ri.Cmd_RemoveCommand( "gl_strings" );

	Mod_FreeAll();

	R_ShutdownImages();

	/* shut down OS specific OpenGL stuff like contexts, etc.  */
	GLimp_Shutdown();

	/* shutdown our QGL subsystem */
	QGL_Shutdown();
}

extern void UpdateHardwareGamma ();

void
R_BeginFrame ( float camera_separation )
{
	gl_state.camera_separation = camera_separation;

	/* change modes if necessary */
	if ( gl_mode->modified || vid_fullscreen->modified )
	{
		cvar_t  *ref;

		ref = ri.Cvar_Get( "vid_ref", "gl", 0 );
		ref->modified = true;
	}

	if ( gl_log->modified )
	{
		GLimp_EnableLogging( gl_log->value );
		gl_log->modified = false;
	}

	if ( gl_log->value )
	{
		GLimp_LogNewFrame();
	}

	if ( vid_gamma->modified )
	{
		vid_gamma->modified = false;

		if ( gl_state.hwgamma )
		{
			UpdateHardwareGamma();
		}
	}

	/* go into 2D mode */
	qglViewport( 0, 0, vid.width, vid.height );
	qglMatrixMode( GL_PROJECTION );
	qglLoadIdentity();
	qglOrtho( 0, vid.width, vid.height, 0, -99999, 99999 );
	qglMatrixMode( GL_MODELVIEW );
	qglLoadIdentity();
	qglDisable( GL_DEPTH_TEST );
	qglDisable( GL_CULL_FACE );
	qglDisable( GL_BLEND );
	qglEnable( GL_ALPHA_TEST );
	qglColor4f( 1, 1, 1, 1 );

	/* draw buffer stuff */
	if ( gl_drawbuffer->modified )
	{
		gl_drawbuffer->modified = false;

		if ( ( gl_state.camera_separation == 0 ) || !gl_state.stereo_enabled )
		{
			if ( Q_stricmp( gl_drawbuffer->string, "GL_FRONT" ) == 0 )
			{
				qglDrawBuffer( GL_FRONT );
			}
			else
			{
				qglDrawBuffer( GL_BACK );
			}
		}
	}

	/* texturemode stuff */
	if ( gl_texturemode->modified )
	{
		R_TextureMode( gl_texturemode->string );
		gl_texturemode->modified = false;
	}

	if ( gl_texturealphamode->modified )
	{
		R_TextureAlphaMode( gl_texturealphamode->string );
		gl_texturealphamode->modified = false;
	}

	if ( gl_texturesolidmode->modified )
	{
		R_TextureSolidMode( gl_texturesolidmode->string );
		gl_texturesolidmode->modified = false;
	}

	/* swapinterval stuff */
	R_UpdateSwapInterval();

	/* clear screen if desired */
	R_Clear();
}

void
R_SetPalette ( const unsigned char *palette )
{
	int i;

	byte *rp = (byte *) r_rawpalette;

	if ( palette )
	{
		for ( i = 0; i < 256; i++ )
		{
			rp [ i * 4 + 0 ] = palette [ i * 3 + 0 ];
			rp [ i * 4 + 1 ] = palette [ i * 3 + 1 ];
			rp [ i * 4 + 2 ] = palette [ i * 3 + 2 ];
			rp [ i * 4 + 3 ] = 0xff;
		}
	}
	else
	{
		for ( i = 0; i < 256; i++ )
		{
			rp [ i * 4 + 0 ] = LittleLong( d_8to24table [ i ] ) & 0xff;
			rp [ i * 4 + 1 ] = ( LittleLong( d_8to24table [ i ] ) >> 8 ) & 0xff;
			rp [ i * 4 + 2 ] = ( LittleLong( d_8to24table [ i ] ) >> 16 ) & 0xff;
			rp [ i * 4 + 3 ] = 0xff;
		}
	}

	R_SetTexturePalette( r_rawpalette );

	qglClearColor( 0, 0, 0, 0 );
	qglClear( GL_COLOR_BUFFER_BIT );
	qglClearColor( 1, 0, 0.5, 0.5 );
}

/* R_DrawBeam */
void
R_DrawBeam ( entity_t *e )
{
	int i;
	float r, g, b;

	vec3_t perpvec;
	vec3_t direction, normalized_direction;
	vec3_t start_points [ NUM_BEAM_SEGS ], end_points [ NUM_BEAM_SEGS ];
	vec3_t oldorigin, origin;

	oldorigin [ 0 ] = e->oldorigin [ 0 ];
	oldorigin [ 1 ] = e->oldorigin [ 1 ];
	oldorigin [ 2 ] = e->oldorigin [ 2 ];

	origin [ 0 ] = e->origin [ 0 ];
	origin [ 1 ] = e->origin [ 1 ];
	origin [ 2 ] = e->origin [ 2 ];

	normalized_direction [ 0 ] = direction [ 0 ] = oldorigin [ 0 ] - origin [ 0 ];
	normalized_direction [ 1 ] = direction [ 1 ] = oldorigin [ 1 ] - origin [ 1 ];
	normalized_direction [ 2 ] = direction [ 2 ] = oldorigin [ 2 ] - origin [ 2 ];

	if ( VectorNormalize( normalized_direction ) == 0 )
	{
		return;
	}

	PerpendicularVector( perpvec, normalized_direction );
	VectorScale( perpvec, e->frame / 2, perpvec );

	for ( i = 0; i < 6; i++ )
	{
		RotatePointAroundVector( start_points [ i ], normalized_direction, perpvec, ( 360.0 / NUM_BEAM_SEGS ) * i );
		VectorAdd( start_points [ i ], origin, start_points [ i ] );
		VectorAdd( start_points [ i ], direction, end_points [ i ] );
	}

	qglDisable( GL_TEXTURE_2D );
	qglEnable( GL_BLEND );
	qglDepthMask( GL_FALSE );

	r = ( LittleLong( d_8to24table [ e->skinnum & 0xFF ] ) ) & 0xFF;
	g = ( LittleLong( d_8to24table [ e->skinnum & 0xFF ] ) >> 8 ) & 0xFF;
	b = ( LittleLong( d_8to24table [ e->skinnum & 0xFF ] ) >> 16 ) & 0xFF;

	r *= 1 / 255.0F;
	g *= 1 / 255.0F;
	b *= 1 / 255.0F;

	qglColor4f( r, g, b, e->alpha );

	qglBegin( GL_TRIANGLE_STRIP );

	for ( i = 0; i < NUM_BEAM_SEGS; i++ )
	{
		qglVertex3fv( start_points [ i ] );
		qglVertex3fv( end_points [ i ] );
		qglVertex3fv( start_points [ ( i + 1 ) % NUM_BEAM_SEGS ] );
		qglVertex3fv( end_points [ ( i + 1 ) % NUM_BEAM_SEGS ] );
	}

	qglEnd();

	qglEnable( GL_TEXTURE_2D );
	qglDisable( GL_BLEND );
	qglDepthMask( GL_TRUE );
}

refexport_t
R_GetRefAPI ( refimport_t rimp )
{
	refexport_t re;

	ri = rimp;

	re.api_version = API_VERSION;

	re.BeginRegistration = R_BeginRegistration;
	re.RegisterModel = R_RegisterModel;
	re.RegisterSkin = R_RegisterSkin;
	re.RegisterPic = Draw_FindPic;
	re.SetSky = R_SetSky;
	re.EndRegistration = R_EndRegistration;

	re.RenderFrame = R_RenderFrame;

	re.DrawGetPicSize = Draw_GetPicSize;
	re.DrawPic = Draw_Pic;
	re.DrawStretchPic = Draw_StretchPic;
	re.DrawChar = Draw_Char;
	re.DrawTileClear = Draw_TileClear;
	re.DrawFill = Draw_Fill;
	re.DrawFadeScreen = Draw_FadeScreen;

	re.DrawStretchRaw = Draw_StretchRaw;

	re.Init = R_Init;
	re.Shutdown = R_Shutdown;

	re.CinematicSetPalette = R_SetPalette;
	re.BeginFrame = R_BeginFrame;
	re.EndFrame = GLimp_EndFrame;

	re.AppActivate = NULL;

	Swap_Init();

	return ( re );
}

/*
 * this is only here so the functions in
 * q_shared.c can link
 */
void
Sys_Error ( char *error, ... )
{
	va_list argptr;
	char text [ 1024 ];

	va_start( argptr, error );
	vsprintf( text, error, argptr );
	va_end( argptr );

	ri.Sys_Error( ERR_FATAL, "%s", text );
}

void
Com_Printf ( char *fmt, ... )
{
	va_list argptr;
	char text [ 1024 ];

	va_start( argptr, fmt );
	vsprintf( text, fmt, argptr );
	va_end( argptr );

	ri.Con_Printf( PRINT_ALL, "%s", text );
}