gl_rsurf.c

Quake 2 Source code for students by Theerthan You can also download from idsoftwares.com

							  fa->light_s, fa->light_t, 
							  smax, tmax, 
							  GL_LIGHTMAP_FORMAT, 
							  GL_UNSIGNED_BYTE, temp );

			fa->lightmapchain = gl_lms.lightmap_surfaces[fa->lightmaptexturenum];
			gl_lms.lightmap_surfaces[fa->lightmaptexturenum] = fa;
		}
		else
		{
			fa->lightmapchain = gl_lms.lightmap_surfaces[0];
			gl_lms.lightmap_surfaces[0] = fa;
		}
	}
	else
	{
		fa->lightmapchain = gl_lms.lightmap_surfaces[fa->lightmaptexturenum];
		gl_lms.lightmap_surfaces[fa->lightmaptexturenum] = fa;
	}
}


/*
================
R_DrawAlphaSurfaces

Draw water surfaces and windows.
The BSP tree is waled front to back, so unwinding the chain
of alpha_surfaces will draw back to front, giving proper ordering.
================
*/
void R_DrawAlphaSurfaces (void)
{
	msurface_t	*s;
	float		intens;

	//
	// go back to the world matrix
	//
    qglLoadMatrixf (r_world_matrix);

	qglEnable (GL_BLEND);
	GL_TexEnv( GL_MODULATE );

	// the textures are prescaled up for a better lighting range,
	// so scale it back down
	intens = gl_state.inverse_intensity;

	for (s=r_alpha_surfaces ; s ; s=s->texturechain)
	{
		GL_Bind(s->texinfo->image->texnum);
		c_brush_polys++;
		if (s->texinfo->flags & SURF_TRANS33)
			qglColor4f (intens,intens,intens,0.33);
		else if (s->texinfo->flags & SURF_TRANS66)
			qglColor4f (intens,intens,intens,0.66);
		else
			qglColor4f (intens,intens,intens,1);
		if (s->flags & SURF_DRAWTURB)
			EmitWaterPolys (s);
		else if(s->texinfo->flags & SURF_FLOWING)			// PGM	9/16/98
			DrawGLFlowingPoly (s);							// PGM
		else
			DrawGLPoly (s->polys);
	}

	GL_TexEnv( GL_REPLACE );
	qglColor4f (1,1,1,1);
	qglDisable (GL_BLEND);

	r_alpha_surfaces = NULL;
}

/*
================
DrawTextureChains
================
*/
void DrawTextureChains (void)
{
	int		i;
	msurface_t	*s;
	image_t		*image;

	c_visible_textures = 0;

//	GL_TexEnv( GL_REPLACE );

	if ( !qglSelectTextureSGIS && !qglActiveTextureARB )
	{
		for ( i = 0, image=gltextures ; i<numgltextures ; i++,image++)
		{
			if (!image->registration_sequence)
				continue;
			s = image->texturechain;
			if (!s)
				continue;
			c_visible_textures++;

			for ( ; s ; s=s->texturechain)
				R_RenderBrushPoly (s);

			image->texturechain = NULL;
		}
	}
	else
	{
		for ( i = 0, image=gltextures ; i<numgltextures ; i++,image++)
		{
			if (!image->registration_sequence)
				continue;
			if (!image->texturechain)
				continue;
			c_visible_textures++;

			for ( s = image->texturechain; s ; s=s->texturechain)
			{
				if ( !( s->flags & SURF_DRAWTURB ) )
					R_RenderBrushPoly (s);
			}
		}

		GL_EnableMultitexture( false );
		for ( i = 0, image=gltextures ; i<numgltextures ; i++,image++)
		{
			if (!image->registration_sequence)
				continue;
			s = image->texturechain;
			if (!s)
				continue;

			for ( ; s ; s=s->texturechain)
			{
				if ( s->flags & SURF_DRAWTURB )
					R_RenderBrushPoly (s);
			}

			image->texturechain = NULL;
		}
//		GL_EnableMultitexture( true );
	}

	GL_TexEnv( GL_REPLACE );
}


static void GL_RenderLightmappedPoly( msurface_t *surf )
{
	int		i, nv = surf->polys->numverts;
	int		map;
	float	*v;
	image_t *image = R_TextureAnimation( surf->texinfo );
	qboolean is_dynamic = false;
	unsigned lmtex = surf->lightmaptexturenum;
	glpoly_t *p;

	for ( map = 0; map < MAXLIGHTMAPS && surf->styles[map] != 255; map++ )
	{
		if ( r_newrefdef.lightstyles[surf->styles[map]].white != surf->cached_light[map] )
			goto dynamic;
	}

	// dynamic this frame or dynamic previously
	if ( ( surf->dlightframe == r_framecount ) )
	{
dynamic:
		if ( gl_dynamic->value )
		{
			if ( !(surf->texinfo->flags & (SURF_SKY|SURF_TRANS33|SURF_TRANS66|SURF_WARP ) ) )
			{
				is_dynamic = true;
			}
		}
	}

	if ( is_dynamic )
	{
		unsigned	temp[128*128];
		int			smax, tmax;

		if ( ( surf->styles[map] >= 32 || surf->styles[map] == 0 ) && ( surf->dlightframe != r_framecount ) )
		{
			smax = (surf->extents[0]>>4)+1;
			tmax = (surf->extents[1]>>4)+1;

			R_BuildLightMap( surf, (void *)temp, smax*4 );
			R_SetCacheState( surf );

			GL_MBind( GL_TEXTURE1, gl_state.lightmap_textures + surf->lightmaptexturenum );

			lmtex = surf->lightmaptexturenum;

			qglTexSubImage2D( GL_TEXTURE_2D, 0,
							  surf->light_s, surf->light_t, 
							  smax, tmax, 
							  GL_LIGHTMAP_FORMAT, 
							  GL_UNSIGNED_BYTE, temp );

		}
		else
		{
			smax = (surf->extents[0]>>4)+1;
			tmax = (surf->extents[1]>>4)+1;

			R_BuildLightMap( surf, (void *)temp, smax*4 );

			GL_MBind( GL_TEXTURE1, gl_state.lightmap_textures + 0 );

			lmtex = 0;

			qglTexSubImage2D( GL_TEXTURE_2D, 0,
							  surf->light_s, surf->light_t, 
							  smax, tmax, 
							  GL_LIGHTMAP_FORMAT, 
							  GL_UNSIGNED_BYTE, temp );

		}

		c_brush_polys++;

		GL_MBind( GL_TEXTURE0, image->texnum );
		GL_MBind( GL_TEXTURE1, gl_state.lightmap_textures + lmtex );

//==========
//PGM
		if (surf->texinfo->flags & SURF_FLOWING)
		{
			float scroll;
		
			scroll = -64 * ( (r_newrefdef.time / 40.0) - (int)(r_newrefdef.time / 40.0) );
			if(scroll == 0.0)
				scroll = -64.0;

			for ( p = surf->polys; p; p = p->chain )
			{
				v = p->verts[0];
				qglBegin (GL_POLYGON);
				for (i=0 ; i< nv; i++, v+= VERTEXSIZE)
				{
					qglMTexCoord2fSGIS( GL_TEXTURE0, (v[3]+scroll), v[4]);
					qglMTexCoord2fSGIS( GL_TEXTURE1, v[5], v[6]);
					qglVertex3fv (v);
				}
				qglEnd ();
			}
		}
		else
		{
			for ( p = surf->polys; p; p = p->chain )
			{
				v = p->verts[0];
				qglBegin (GL_POLYGON);
				for (i=0 ; i< nv; i++, v+= VERTEXSIZE)
				{
					qglMTexCoord2fSGIS( GL_TEXTURE0, v[3], v[4]);
					qglMTexCoord2fSGIS( GL_TEXTURE1, v[5], v[6]);
					qglVertex3fv (v);
				}
				qglEnd ();
			}
		}
//PGM
//==========
	}
	else
	{
		c_brush_polys++;

		GL_MBind( GL_TEXTURE0, image->texnum );
		GL_MBind( GL_TEXTURE1, gl_state.lightmap_textures + lmtex );

//==========
//PGM
		if (surf->texinfo->flags & SURF_FLOWING)
		{
			float scroll;
		
			scroll = -64 * ( (r_newrefdef.time / 40.0) - (int)(r_newrefdef.time / 40.0) );
			if(scroll == 0.0)
				scroll = -64.0;

			for ( p = surf->polys; p; p = p->chain )
			{
				v = p->verts[0];
				qglBegin (GL_POLYGON);
				for (i=0 ; i< nv; i++, v+= VERTEXSIZE)
				{
					qglMTexCoord2fSGIS( GL_TEXTURE0, (v[3]+scroll), v[4]);
					qglMTexCoord2fSGIS( GL_TEXTURE1, v[5], v[6]);
					qglVertex3fv (v);
				}
				qglEnd ();
			}
		}
		else
		{
//PGM
//==========
			for ( p = surf->polys; p; p = p->chain )
			{
				v = p->verts[0];
				qglBegin (GL_POLYGON);
				for (i=0 ; i< nv; i++, v+= VERTEXSIZE)
				{
					qglMTexCoord2fSGIS( GL_TEXTURE0, v[3], v[4]);
					qglMTexCoord2fSGIS( GL_TEXTURE1, v[5], v[6]);
					qglVertex3fv (v);
				}
				qglEnd ();
			}
//==========
//PGM
		}
//PGM
//==========
	}
}

/*
=================
R_DrawInlineBModel
=================
*/
void R_DrawInlineBModel (void)
{
	int			i, k;
	cplane_t	*pplane;
	float		dot;
	msurface_t	*psurf;
	dlight_t	*lt;

	// calculate dynamic lighting for bmodel
	if ( !gl_flashblend->value )
	{
		lt = r_newrefdef.dlights;
		for (k=0 ; k<r_newrefdef.num_dlights ; k++, lt++)
		{
			R_MarkLights (lt, 1<<k, currentmodel->nodes + currentmodel->firstnode);
		}
	}

	psurf = &currentmodel->surfaces[currentmodel->firstmodelsurface];

	if ( currententity->flags & RF_TRANSLUCENT )
	{
		qglEnable (GL_BLEND);
		qglColor4f (1,1,1,0.25);
		GL_TexEnv( GL_MODULATE );
	}

	//
	// draw texture
	//
	for (i=0 ; i<currentmodel->nummodelsurfaces ; i++, psurf++)
	{
	// find which side of the node we are on
		pplane = psurf->plane;

		dot = DotProduct (modelorg, pplane->normal) - pplane->dist;

	// draw the polygon
		if (((psurf->flags & SURF_PLANEBACK) && (dot < -BACKFACE_EPSILON)) ||
			(!(psurf->flags & SURF_PLANEBACK) && (dot > BACKFACE_EPSILON)))
		{
			if (psurf->texinfo->flags & (SURF_TRANS33|SURF_TRANS66) )
			{	// add to the translucent chain
				psurf->texturechain = r_alpha_surfaces;
				r_alpha_surfaces = psurf;
			}
			else if ( qglMTexCoord2fSGIS && !( psurf->flags & SURF_DRAWTURB ) )
			{
				GL_RenderLightmappedPoly( psurf );
			}
			else
			{
				GL_EnableMultitexture( false );
				R_RenderBrushPoly( psurf );
				GL_EnableMultitexture( true );
			}
		}
	}

	if ( !(currententity->flags & RF_TRANSLUCENT) )
	{
		if ( !qglMTexCoord2fSGIS )
			R_BlendLightmaps ();
	}
	else
	{
		qglDisable (GL_BLEND);
		qglColor4f (1,1,1,1);
		GL_TexEnv( GL_REPLACE );
	}
}

/*
=================
R_DrawBrushModel
=================
*/
void R_DrawBrushModel (entity_t *e)
{
	vec3_t		mins, maxs;
	int			i;
	qboolean	rotated;

	if (currentmodel->nummodelsurfaces == 0)
		return;

	currententity = e;
	gl_state.currenttextures[0] = gl_state.currenttextures[1] = -1;

	if (e->angles[0] || e->angles[1] || e->angles[2])
	{
		rotated = true;
		for (i=0 ; i<3 ; i++)
		{
			mins[i] = e->origin[i] - currentmodel->radius;
			maxs[i] = e->origin[i] + currentmodel->radius;
		}
	}
	else
	{
		rotated = false;
		VectorAdd (e->origin, currentmodel->mins, mins);
		VectorAdd (e->origin, currentmodel->maxs, maxs);
	}

	if (R_CullBox (mins, maxs))
		return;

	qglColor3f (1,1,1);
	memset (gl_lms.lightmap_surfaces, 0, sizeof(gl_lms.lightmap_surfaces));

	VectorSubtract (r_newrefdef.vieworg, e->origin, modelorg);
	if (rotated)
	{
		vec3_t	temp;
		vec3_t	forward, right, up;

		VectorCopy (modelorg, temp);
		AngleVectors (e->angles, forward, right, up);
		modelorg[0] = DotProduct (temp, forward);
		modelorg[1] = -DotProduct (temp, right);
		modelorg[2] = DotProduct (temp, up);
	}

    qglPushMatrix ();
e->angles[0] = -e->angles[0];	// stupid quake bug
e->angles[2] = -e->angles[2];	// stupid quake bug
	R_RotateForEntity (e);
e->angles[0] = -e->angles[0];	// stupid quake bug
e->angles[2] = -e->angles[2];	// stupid quake bug

	GL_EnableMultitexture( true );
	GL_SelectTexture( GL_TEXTURE0);
	GL_TexEnv( GL_REPLACE );
	GL_SelectTexture( GL_TEXTURE1);
	GL_TexEnv( GL_MODULATE );

	R_DrawInlineBModel ();
	GL_EnableMultitexture( false );

	qglPopMatrix ();
}

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

	WORLD MODEL

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

/*
================
R_RecursiveWorldNode
================
*/
void R_RecursiveWorldNode (mnode_t *node)
{
	int			c, side, sidebit;
	cplane_t	*plane;
	msurface_t	*surf, **mark;
	mleaf_t		*pleaf;
	float		dot;
	image_t		*image;

	if (node->contents == CONTENTS_SOLID)
		return;		// solid

	if (node->visframe != r_visframecount)
		return;
	if (R_CullBox (node->minmaxs, node->minmaxs+3))
		return;
	
// if a leaf node, draw stuff
	if (node->contents != -1)
	{
		pleaf = (mleaf_t *)node;

		// check for door connected areas
		if (r_newrefdef.areabits)
		{
			if (! (r_newrefdef.areabits[pleaf->area>>3] & (1<<(pleaf->area&7)) ) )
				return;		// not visible
		}

		mark = pleaf->firstmarksurface;
		c = pleaf->nummarksurfaces;

		if (c)
		{
			do
			{
				(*mark)->visframe = r_framecount;
				mark++;
			} while (--c);
		}

		return;
	}

// node is just a decision point, so go down the apropriate sides

// find which side of the node we are on
	plane = node->plane;

	switch (plane->type)
	{
	case PLANE_X:
		dot = modelorg[0] - plane->dist;
		break;
	case PLANE_Y:
		dot = modelorg[1] - plane->dist;
		break;
	case PLANE_Z:
		dot = modelorg[2] - plane->dist;
		break;
	default:
		dot = DotProduct (modelorg, plane->normal) - plane->dist;
		break;
	}

	if (dot >= 0)
	{
		side = 0;
		sidebit = 0;
	}
	else
	{
		side = 1;
		sidebit = SURF_PLANEBACK;
	}