tr_bsp.c

3D 游戏界的大牛人 John Carmack 终于放出了 Q3 的源代码

			else
				out->children[j] = s_worldData.nodes + numNodes + (-1 - p);
		}
	}
	
	// load leafs
	inLeaf = (void *)(fileBase + leafLump->fileofs);
	for ( i=0 ; i<numLeafs ; i++, inLeaf++, out++)
	{
		for (j=0 ; j<3 ; j++)
		{
			out->mins[j] = LittleLong (inLeaf->mins[j]);
			out->maxs[j] = LittleLong (inLeaf->maxs[j]);
		}

		out->cluster = LittleLong(inLeaf->cluster);
		out->area = LittleLong(inLeaf->area);

		if ( out->cluster >= s_worldData.numClusters ) {
			s_worldData.numClusters = out->cluster + 1;
		}

		out->firstmarksurface = s_worldData.marksurfaces +
			LittleLong(inLeaf->firstLeafSurface);
		out->nummarksurfaces = LittleLong(inLeaf->numLeafSurfaces);
	}	

	// chain decendants
	R_SetParent (s_worldData.nodes, NULL);
}

//=============================================================================

/*
=================
R_LoadShaders
=================
*/
static	void R_LoadShaders( lump_t *l ) {	
	int		i, count;
	dshader_t	*in, *out;
	
	in = (void *)(fileBase + l->fileofs);
	if (l->filelen % sizeof(*in))
		ri.Error (ERR_DROP, "LoadMap: funny lump size in %s",s_worldData.name);
	count = l->filelen / sizeof(*in);
	out = ri.Hunk_Alloc ( count*sizeof(*out), h_low );

	s_worldData.shaders = out;
	s_worldData.numShaders = count;

	Com_Memcpy( out, in, count*sizeof(*out) );

	for ( i=0 ; i<count ; i++ ) {
		out[i].surfaceFlags = LittleLong( out[i].surfaceFlags );
		out[i].contentFlags = LittleLong( out[i].contentFlags );
	}
}


/*
=================
R_LoadMarksurfaces
=================
*/
static	void R_LoadMarksurfaces (lump_t *l)
{	
	int		i, j, count;
	int		*in;
	msurface_t **out;
	
	in = (void *)(fileBase + l->fileofs);
	if (l->filelen % sizeof(*in))
		ri.Error (ERR_DROP, "LoadMap: funny lump size in %s",s_worldData.name);
	count = l->filelen / sizeof(*in);
	out = ri.Hunk_Alloc ( count*sizeof(*out), h_low);	

	s_worldData.marksurfaces = out;
	s_worldData.nummarksurfaces = count;

	for ( i=0 ; i<count ; i++)
	{
		j = LittleLong(in[i]);
		out[i] = s_worldData.surfaces + j;
	}
}


/*
=================
R_LoadPlanes
=================
*/
static	void R_LoadPlanes( lump_t *l ) {
	int			i, j;
	cplane_t	*out;
	dplane_t 	*in;
	int			count;
	int			bits;
	
	in = (void *)(fileBase + l->fileofs);
	if (l->filelen % sizeof(*in))
		ri.Error (ERR_DROP, "LoadMap: funny lump size in %s",s_worldData.name);
	count = l->filelen / sizeof(*in);
	out = ri.Hunk_Alloc ( count*2*sizeof(*out), h_low);	
	
	s_worldData.planes = out;
	s_worldData.numplanes = count;

	for ( i=0 ; i<count ; i++, in++, out++) {
		bits = 0;
		for (j=0 ; j<3 ; j++) {
			out->normal[j] = LittleFloat (in->normal[j]);
			if (out->normal[j] < 0) {
				bits |= 1<<j;
			}
		}

		out->dist = LittleFloat (in->dist);
		out->type = PlaneTypeForNormal( out->normal );
		out->signbits = bits;
	}
}

/*
=================
R_LoadFogs

=================
*/
static	void R_LoadFogs( lump_t *l, lump_t *brushesLump, lump_t *sidesLump ) {
	int			i;
	fog_t		*out;
	dfog_t		*fogs;
	dbrush_t 	*brushes, *brush;
	dbrushside_t	*sides;
	int			count, brushesCount, sidesCount;
	int			sideNum;
	int			planeNum;
	shader_t	*shader;
	float		d;
	int			firstSide;

	fogs = (void *)(fileBase + l->fileofs);
	if (l->filelen % sizeof(*fogs)) {
		ri.Error (ERR_DROP, "LoadMap: funny lump size in %s",s_worldData.name);
	}
	count = l->filelen / sizeof(*fogs);

	// create fog strucutres for them
	s_worldData.numfogs = count + 1;
	s_worldData.fogs = ri.Hunk_Alloc ( s_worldData.numfogs*sizeof(*out), h_low);
	out = s_worldData.fogs + 1;

	if ( !count ) {
		return;
	}

	brushes = (void *)(fileBase + brushesLump->fileofs);
	if (brushesLump->filelen % sizeof(*brushes)) {
		ri.Error (ERR_DROP, "LoadMap: funny lump size in %s",s_worldData.name);
	}
	brushesCount = brushesLump->filelen / sizeof(*brushes);

	sides = (void *)(fileBase + sidesLump->fileofs);
	if (sidesLump->filelen % sizeof(*sides)) {
		ri.Error (ERR_DROP, "LoadMap: funny lump size in %s",s_worldData.name);
	}
	sidesCount = sidesLump->filelen / sizeof(*sides);

	for ( i=0 ; i<count ; i++, fogs++) {
		out->originalBrushNumber = LittleLong( fogs->brushNum );

		if ( (unsigned)out->originalBrushNumber >= brushesCount ) {
			ri.Error( ERR_DROP, "fog brushNumber out of range" );
		}
		brush = brushes + out->originalBrushNumber;

		firstSide = LittleLong( brush->firstSide );

			if ( (unsigned)firstSide > sidesCount - 6 ) {
			ri.Error( ERR_DROP, "fog brush sideNumber out of range" );
		}

		// brushes are always sorted with the axial sides first
		sideNum = firstSide + 0;
		planeNum = LittleLong( sides[ sideNum ].planeNum );
		out->bounds[0][0] = -s_worldData.planes[ planeNum ].dist;

		sideNum = firstSide + 1;
		planeNum = LittleLong( sides[ sideNum ].planeNum );
		out->bounds[1][0] = s_worldData.planes[ planeNum ].dist;

		sideNum = firstSide + 2;
		planeNum = LittleLong( sides[ sideNum ].planeNum );
		out->bounds[0][1] = -s_worldData.planes[ planeNum ].dist;

		sideNum = firstSide + 3;
		planeNum = LittleLong( sides[ sideNum ].planeNum );
		out->bounds[1][1] = s_worldData.planes[ planeNum ].dist;

		sideNum = firstSide + 4;
		planeNum = LittleLong( sides[ sideNum ].planeNum );
		out->bounds[0][2] = -s_worldData.planes[ planeNum ].dist;

		sideNum = firstSide + 5;
		planeNum = LittleLong( sides[ sideNum ].planeNum );
		out->bounds[1][2] = s_worldData.planes[ planeNum ].dist;

		// get information from the shader for fog parameters
		shader = R_FindShader( fogs->shader, LIGHTMAP_NONE, qtrue );

		out->parms = shader->fogParms;

		out->colorInt = ColorBytes4 ( shader->fogParms.color[0] * tr.identityLight, 
			                          shader->fogParms.color[1] * tr.identityLight, 
			                          shader->fogParms.color[2] * tr.identityLight, 1.0 );

		d = shader->fogParms.depthForOpaque < 1 ? 1 : shader->fogParms.depthForOpaque;
		out->tcScale = 1.0f / ( d * 8 );

		// set the gradient vector
		sideNum = LittleLong( fogs->visibleSide );

		if ( sideNum == -1 ) {
			out->hasSurface = qfalse;
		} else {
			out->hasSurface = qtrue;
			planeNum = LittleLong( sides[ firstSide + sideNum ].planeNum );
			VectorSubtract( vec3_origin, s_worldData.planes[ planeNum ].normal, out->surface );
			out->surface[3] = -s_worldData.planes[ planeNum ].dist;
		}

		out++;
	}

}


/*
================
R_LoadLightGrid

================
*/
void R_LoadLightGrid( lump_t *l ) {
	int		i;
	vec3_t	maxs;
	int		numGridPoints;
	world_t	*w;
	float	*wMins, *wMaxs;

	w = &s_worldData;

	w->lightGridInverseSize[0] = 1.0f / w->lightGridSize[0];
	w->lightGridInverseSize[1] = 1.0f / w->lightGridSize[1];
	w->lightGridInverseSize[2] = 1.0f / w->lightGridSize[2];

	wMins = w->bmodels[0].bounds[0];
	wMaxs = w->bmodels[0].bounds[1];

	for ( i = 0 ; i < 3 ; i++ ) {
		w->lightGridOrigin[i] = w->lightGridSize[i] * ceil( wMins[i] / w->lightGridSize[i] );
		maxs[i] = w->lightGridSize[i] * floor( wMaxs[i] / w->lightGridSize[i] );
		w->lightGridBounds[i] = (maxs[i] - w->lightGridOrigin[i])/w->lightGridSize[i] + 1;
	}

	numGridPoints = w->lightGridBounds[0] * w->lightGridBounds[1] * w->lightGridBounds[2];

	if ( l->filelen != numGridPoints * 8 ) {
		ri.Printf( PRINT_WARNING, "WARNING: light grid mismatch\n" );
		w->lightGridData = NULL;
		return;
	}

	w->lightGridData = ri.Hunk_Alloc( l->filelen, h_low );
	Com_Memcpy( w->lightGridData, (void *)(fileBase + l->fileofs), l->filelen );

	// deal with overbright bits
	for ( i = 0 ; i < numGridPoints ; i++ ) {
		R_ColorShiftLightingBytes( &w->lightGridData[i*8], &w->lightGridData[i*8] );
		R_ColorShiftLightingBytes( &w->lightGridData[i*8+3], &w->lightGridData[i*8+3] );
	}
}

/*
================
R_LoadEntities
================
*/
void R_LoadEntities( lump_t *l ) {
	char *p, *token, *s;
	char keyname[MAX_TOKEN_CHARS];
	char value[MAX_TOKEN_CHARS];
	world_t	*w;

	w = &s_worldData;
	w->lightGridSize[0] = 64;
	w->lightGridSize[1] = 64;
	w->lightGridSize[2] = 128;

	p = (char *)(fileBase + l->fileofs);

	// store for reference by the cgame
	w->entityString = ri.Hunk_Alloc( l->filelen + 1, h_low );
	strcpy( w->entityString, p );
	w->entityParsePoint = w->entityString;

	token = COM_ParseExt( &p, qtrue );
	if (!*token || *token != '{') {
		return;
	}

	// only parse the world spawn
	while ( 1 ) {	
		// parse key
		token = COM_ParseExt( &p, qtrue );

		if ( !*token || *token == '}' ) {
			break;
		}
		Q_strncpyz(keyname, token, sizeof(keyname));

		// parse value
		token = COM_ParseExt( &p, qtrue );

		if ( !*token || *token == '}' ) {
			break;
		}
		Q_strncpyz(value, token, sizeof(value));

		// check for remapping of shaders for vertex lighting
		s = "vertexremapshader";
		if (!Q_strncmp(keyname, s, strlen(s)) ) {
			s = strchr(value, ';');
			if (!s) {
				ri.Printf( PRINT_WARNING, "WARNING: no semi colon in vertexshaderremap '%s'\n", value );
				break;
			}
			*s++ = 0;
			if (r_vertexLight->integer) {
				R_RemapShader(value, s, "0");
			}
			continue;
		}
		// check for remapping of shaders
		s = "remapshader";
		if (!Q_strncmp(keyname, s, strlen(s)) ) {
			s = strchr(value, ';');
			if (!s) {
				ri.Printf( PRINT_WARNING, "WARNING: no semi colon in shaderremap '%s'\n", value );
				break;
			}
			*s++ = 0;
			R_RemapShader(value, s, "0");
			continue;
		}
		// check for a different grid size
		if (!Q_stricmp(keyname, "gridsize")) {
			sscanf(value, "%f %f %f", &w->lightGridSize[0], &w->lightGridSize[1], &w->lightGridSize[2] );
			continue;
		}
	}
}

/*
=================
R_GetEntityToken
=================
*/
qboolean R_GetEntityToken( char *buffer, int size ) {
	const char	*s;

	s = COM_Parse( &s_worldData.entityParsePoint );
	Q_strncpyz( buffer, s, size );
	if ( !s_worldData.entityParsePoint || !s[0] ) {
		s_worldData.entityParsePoint = s_worldData.entityString;
		return qfalse;
	} else {
		return qtrue;
	}
}

/*
=================
RE_LoadWorldMap

Called directly from cgame
=================
*/
void RE_LoadWorldMap( const char *name ) {
	int			i;
	dheader_t	*header;
	byte		*buffer;
	byte		*startMarker;

	if ( tr.worldMapLoaded ) {
		ri.Error( ERR_DROP, "ERROR: attempted to redundantly load world map\n" );
	}

	// set default sun direction to be used if it isn't
	// overridden by a shader
	tr.sunDirection[0] = 0.45f;
	tr.sunDirection[1] = 0.3f;
	tr.sunDirection[2] = 0.9f;

	VectorNormalize( tr.sunDirection );

	tr.worldMapLoaded = qtrue;

	// load it
    ri.FS_ReadFile( name, (void **)&buffer );
	if ( !buffer ) {
		ri.Error (ERR_DROP, "RE_LoadWorldMap: %s not found", name);
	}

	// clear tr.world so if the level fails to load, the next
	// try will not look at the partially loaded version
	tr.world = NULL;

	Com_Memset( &s_worldData, 0, sizeof( s_worldData ) );
	Q_strncpyz( s_worldData.name, name, sizeof( s_worldData.name ) );

	Q_strncpyz( s_worldData.baseName, COM_SkipPath( s_worldData.name ), sizeof( s_worldData.name ) );
	COM_StripExtension( s_worldData.baseName, s_worldData.baseName );

	startMarker = ri.Hunk_Alloc(0, h_low);
	c_gridVerts = 0;

	header = (dheader_t *)buffer;
	fileBase = (byte *)header;

	i = LittleLong (header->version);
	if ( i != BSP_VERSION ) {
		ri.Error (ERR_DROP, "RE_LoadWorldMap: %s has wrong version number (%i should be %i)", 
			name, i, BSP_VERSION);
	}

	// swap all the lumps
	for (i=0 ; i<sizeof(dheader_t)/4 ; i++) {
		((int *)header)[i] = LittleLong ( ((int *)header)[i]);
	}

	// load into heap
	R_LoadShaders( &header->lumps[LUMP_SHADERS] );
	R_LoadLightmaps( &header->lumps[LUMP_LIGHTMAPS] );
	R_LoadPlanes (&header->lumps[LUMP_PLANES]);
	R_LoadFogs( &header->lumps[LUMP_FOGS], &header->lumps[LUMP_BRUSHES], &header->lumps[LUMP_BRUSHSIDES] );
	R_LoadSurfaces( &header->lumps[LUMP_SURFACES], &header->lumps[LUMP_DRAWVERTS], &header->lumps[LUMP_DRAWINDEXES] );
	R_LoadMarksurfaces (&header->lumps[LUMP_LEAFSURFACES]);
	R_LoadNodesAndLeafs (&header->lumps[LUMP_NODES], &header->lumps[LUMP_LEAFS]);
	R_LoadSubmodels (&header->lumps[LUMP_MODELS]);
	R_LoadVisibility( &header->lumps[LUMP_VISIBILITY] );
	R_LoadEntities( &header->lumps[LUMP_ENTITIES] );
	R_LoadLightGrid( &header->lumps[LUMP_LIGHTGRID] );

	s_worldData.dataSize = (byte *)ri.Hunk_Alloc(0, h_low) - startMarker;

	// only set tr.world now that we know the entire level has loaded properly
	tr.world = &s_worldData;

    ri.FS_FreeFile( buffer );
}