be_aas_file.c

3D 游戏界的大牛人 John Carmack 终于放出了 Q3 的源代码

	//
	if (!length)
	{
		//just alloc a dummy
		return (char *) GetClearedHunkMemory(size+1);
	} //end if
	//seek to the data
	if (offset != *lastoffset)
	{
		botimport.Print(PRT_WARNING, "AAS file not sequentially read\n");
		if (botimport.FS_Seek(fp, offset, FS_SEEK_SET))
		{
			AAS_Error("can't seek to aas lump\n");
			AAS_DumpAASData();
			botimport.FS_FCloseFile(fp);
			return 0;
		} //end if
	} //end if
	//allocate memory
	buf = (char *) GetClearedHunkMemory(length+1);
	//read the data
	if (length)
	{
		botimport.FS_Read(buf, length, fp );
		*lastoffset += length;
	} //end if
	return buf;
} //end of the function AAS_LoadAASLump
//===========================================================================
//
// Parameter:			-
// Returns:				-
// Changes Globals:		-
//===========================================================================
void AAS_DData(unsigned char *data, int size)
{
	int i;

	for (i = 0; i < size; i++)
	{
		data[i] ^= (unsigned char) i * 119;
	} //end for
} //end of the function AAS_DData
//===========================================================================
// load an aas file
//
// Parameter:			-
// Returns:				-
// Changes Globals:		-
//===========================================================================
int AAS_LoadAASFile(char *filename)
{
	fileHandle_t fp;
	aas_header_t header;
	int offset, length, lastoffset;

	botimport.Print(PRT_MESSAGE, "trying to load %s\n", filename);
	//dump current loaded aas file
	AAS_DumpAASData();
	//open the file
	botimport.FS_FOpenFile( filename, &fp, FS_READ );
	if (!fp)
	{
		AAS_Error("can't open %s\n", filename);
		return BLERR_CANNOTOPENAASFILE;
	} //end if
	//read the header
	botimport.FS_Read(&header, sizeof(aas_header_t), fp );
	lastoffset = sizeof(aas_header_t);
	//check header identification
	header.ident = LittleLong(header.ident);
	if (header.ident != AASID)
	{
		AAS_Error("%s is not an AAS file\n", filename);
		botimport.FS_FCloseFile(fp);
		return BLERR_WRONGAASFILEID;
	} //end if
	//check the version
	header.version = LittleLong(header.version);
	//
	if (header.version != AASVERSION_OLD && header.version != AASVERSION)
	{
		AAS_Error("aas file %s is version %i, not %i\n", filename, header.version, AASVERSION);
		botimport.FS_FCloseFile(fp);
		return BLERR_WRONGAASFILEVERSION;
	} //end if
	//
	if (header.version == AASVERSION)
	{
		AAS_DData((unsigned char *) &header + 8, sizeof(aas_header_t) - 8);
	} //end if
	//
	aasworld.bspchecksum = atoi(LibVarGetString( "sv_mapChecksum"));
	if (LittleLong(header.bspchecksum) != aasworld.bspchecksum)
	{
		AAS_Error("aas file %s is out of date\n", filename);
		botimport.FS_FCloseFile(fp);
		return BLERR_WRONGAASFILEVERSION;
	} //end if
	//load the lumps:
	//bounding boxes
	offset = LittleLong(header.lumps[AASLUMP_BBOXES].fileofs);
	length = LittleLong(header.lumps[AASLUMP_BBOXES].filelen);
	aasworld.bboxes = (aas_bbox_t *) AAS_LoadAASLump(fp, offset, length, &lastoffset, sizeof(aas_bbox_t));
	aasworld.numbboxes = length / sizeof(aas_bbox_t);
	if (aasworld.numbboxes && !aasworld.bboxes) return BLERR_CANNOTREADAASLUMP;
	//vertexes
	offset = LittleLong(header.lumps[AASLUMP_VERTEXES].fileofs);
	length = LittleLong(header.lumps[AASLUMP_VERTEXES].filelen);
	aasworld.vertexes = (aas_vertex_t *) AAS_LoadAASLump(fp, offset, length, &lastoffset, sizeof(aas_vertex_t));
	aasworld.numvertexes = length / sizeof(aas_vertex_t);
	if (aasworld.numvertexes && !aasworld.vertexes) return BLERR_CANNOTREADAASLUMP;
	//planes
	offset = LittleLong(header.lumps[AASLUMP_PLANES].fileofs);
	length = LittleLong(header.lumps[AASLUMP_PLANES].filelen);
	aasworld.planes = (aas_plane_t *) AAS_LoadAASLump(fp, offset, length, &lastoffset, sizeof(aas_plane_t));
	aasworld.numplanes = length / sizeof(aas_plane_t);
	if (aasworld.numplanes && !aasworld.planes) return BLERR_CANNOTREADAASLUMP;
	//edges
	offset = LittleLong(header.lumps[AASLUMP_EDGES].fileofs);
	length = LittleLong(header.lumps[AASLUMP_EDGES].filelen);
	aasworld.edges = (aas_edge_t *) AAS_LoadAASLump(fp, offset, length, &lastoffset, sizeof(aas_edge_t));
	aasworld.numedges = length / sizeof(aas_edge_t);
	if (aasworld.numedges && !aasworld.edges) return BLERR_CANNOTREADAASLUMP;
	//edgeindex
	offset = LittleLong(header.lumps[AASLUMP_EDGEINDEX].fileofs);
	length = LittleLong(header.lumps[AASLUMP_EDGEINDEX].filelen);
	aasworld.edgeindex = (aas_edgeindex_t *) AAS_LoadAASLump(fp, offset, length, &lastoffset, sizeof(aas_edgeindex_t));
	aasworld.edgeindexsize = length / sizeof(aas_edgeindex_t);
	if (aasworld.edgeindexsize && !aasworld.edgeindex) return BLERR_CANNOTREADAASLUMP;
	//faces
	offset = LittleLong(header.lumps[AASLUMP_FACES].fileofs);
	length = LittleLong(header.lumps[AASLUMP_FACES].filelen);
	aasworld.faces = (aas_face_t *) AAS_LoadAASLump(fp, offset, length, &lastoffset, sizeof(aas_face_t));
	aasworld.numfaces = length / sizeof(aas_face_t);
	if (aasworld.numfaces && !aasworld.faces) return BLERR_CANNOTREADAASLUMP;
	//faceindex
	offset = LittleLong(header.lumps[AASLUMP_FACEINDEX].fileofs);
	length = LittleLong(header.lumps[AASLUMP_FACEINDEX].filelen);
	aasworld.faceindex = (aas_faceindex_t *) AAS_LoadAASLump(fp, offset, length, &lastoffset, sizeof(aas_faceindex_t));
	aasworld.faceindexsize = length / sizeof(aas_faceindex_t);
	if (aasworld.faceindexsize && !aasworld.faceindex) return BLERR_CANNOTREADAASLUMP;
	//convex areas
	offset = LittleLong(header.lumps[AASLUMP_AREAS].fileofs);
	length = LittleLong(header.lumps[AASLUMP_AREAS].filelen);
	aasworld.areas = (aas_area_t *) AAS_LoadAASLump(fp, offset, length, &lastoffset, sizeof(aas_area_t));
	aasworld.numareas = length / sizeof(aas_area_t);
	if (aasworld.numareas && !aasworld.areas) return BLERR_CANNOTREADAASLUMP;
	//area settings
	offset = LittleLong(header.lumps[AASLUMP_AREASETTINGS].fileofs);
	length = LittleLong(header.lumps[AASLUMP_AREASETTINGS].filelen);
	aasworld.areasettings = (aas_areasettings_t *) AAS_LoadAASLump(fp, offset, length, &lastoffset, sizeof(aas_areasettings_t));
	aasworld.numareasettings = length / sizeof(aas_areasettings_t);
	if (aasworld.numareasettings && !aasworld.areasettings) return BLERR_CANNOTREADAASLUMP;
	//reachability list
	offset = LittleLong(header.lumps[AASLUMP_REACHABILITY].fileofs);
	length = LittleLong(header.lumps[AASLUMP_REACHABILITY].filelen);
	aasworld.reachability = (aas_reachability_t *) AAS_LoadAASLump(fp, offset, length, &lastoffset, sizeof(aas_reachability_t));
	aasworld.reachabilitysize = length / sizeof(aas_reachability_t);
	if (aasworld.reachabilitysize && !aasworld.reachability) return BLERR_CANNOTREADAASLUMP;
	//nodes
	offset = LittleLong(header.lumps[AASLUMP_NODES].fileofs);
	length = LittleLong(header.lumps[AASLUMP_NODES].filelen);
	aasworld.nodes = (aas_node_t *) AAS_LoadAASLump(fp, offset, length, &lastoffset, sizeof(aas_node_t));
	aasworld.numnodes = length / sizeof(aas_node_t);
	if (aasworld.numnodes && !aasworld.nodes) return BLERR_CANNOTREADAASLUMP;
	//cluster portals
	offset = LittleLong(header.lumps[AASLUMP_PORTALS].fileofs);
	length = LittleLong(header.lumps[AASLUMP_PORTALS].filelen);
	aasworld.portals = (aas_portal_t *) AAS_LoadAASLump(fp, offset, length, &lastoffset, sizeof(aas_portal_t));
	aasworld.numportals = length / sizeof(aas_portal_t);
	if (aasworld.numportals && !aasworld.portals) return BLERR_CANNOTREADAASLUMP;
	//cluster portal index
	offset = LittleLong(header.lumps[AASLUMP_PORTALINDEX].fileofs);
	length = LittleLong(header.lumps[AASLUMP_PORTALINDEX].filelen);
	aasworld.portalindex = (aas_portalindex_t *) AAS_LoadAASLump(fp, offset, length, &lastoffset, sizeof(aas_portalindex_t));
	aasworld.portalindexsize = length / sizeof(aas_portalindex_t);
	if (aasworld.portalindexsize && !aasworld.portalindex) return BLERR_CANNOTREADAASLUMP;
	//clusters
	offset = LittleLong(header.lumps[AASLUMP_CLUSTERS].fileofs);
	length = LittleLong(header.lumps[AASLUMP_CLUSTERS].filelen);
	aasworld.clusters = (aas_cluster_t *) AAS_LoadAASLump(fp, offset, length, &lastoffset, sizeof(aas_cluster_t));
	aasworld.numclusters = length / sizeof(aas_cluster_t);
	if (aasworld.numclusters && !aasworld.clusters) return BLERR_CANNOTREADAASLUMP;
	//swap everything
	AAS_SwapAASData();
	//aas file is loaded
	aasworld.loaded = qtrue;
	//close the file
	botimport.FS_FCloseFile(fp);
	//
#ifdef AASFILEDEBUG
	AAS_FileInfo();
#endif //AASFILEDEBUG
	//
	return BLERR_NOERROR;
} //end of the function AAS_LoadAASFile
//===========================================================================
//
// Parameter:				-
// Returns:					-
// Changes Globals:		-
//===========================================================================
static int AAS_WriteAASLump_offset;

int AAS_WriteAASLump(fileHandle_t fp, aas_header_t *h, int lumpnum, void *data, int length)
{
	aas_lump_t *lump;

	lump = &h->lumps[lumpnum];
	
	lump->fileofs = LittleLong(AAS_WriteAASLump_offset);	//LittleLong(ftell(fp));
	lump->filelen = LittleLong(length);

	if (length > 0)
	{
		botimport.FS_Write(data, length, fp );
	} //end if

	AAS_WriteAASLump_offset += length;

	return qtrue;
} //end of the function AAS_WriteAASLump
//===========================================================================
// aas data is useless after writing to file because it is byte swapped
//
// Parameter:				-
// Returns:					-
// Changes Globals:		-
//===========================================================================
qboolean AAS_WriteAASFile(char *filename)
{
	aas_header_t header;
	fileHandle_t fp;

	botimport.Print(PRT_MESSAGE, "writing %s\n", filename);
	//swap the aas data
	AAS_SwapAASData();
	//initialize the file header
	Com_Memset(&header, 0, sizeof(aas_header_t));
	header.ident = LittleLong(AASID);
	header.version = LittleLong(AASVERSION);
	header.bspchecksum = LittleLong(aasworld.bspchecksum);
	//open a new file
	botimport.FS_FOpenFile( filename, &fp, FS_WRITE );
	if (!fp)
	{
		botimport.Print(PRT_ERROR, "error opening %s\n", filename);
		return qfalse;
	} //end if
	//write the header
	botimport.FS_Write(&header, sizeof(aas_header_t), fp);
	AAS_WriteAASLump_offset = sizeof(aas_header_t);
	//add the data lumps to the file
	if (!AAS_WriteAASLump(fp, &header, AASLUMP_BBOXES, aasworld.bboxes,
		aasworld.numbboxes * sizeof(aas_bbox_t))) return qfalse;
	if (!AAS_WriteAASLump(fp, &header, AASLUMP_VERTEXES, aasworld.vertexes,
		aasworld.numvertexes * sizeof(aas_vertex_t))) return qfalse;
	if (!AAS_WriteAASLump(fp, &header, AASLUMP_PLANES, aasworld.planes,
		aasworld.numplanes * sizeof(aas_plane_t))) return qfalse;
	if (!AAS_WriteAASLump(fp, &header, AASLUMP_EDGES, aasworld.edges,
		aasworld.numedges * sizeof(aas_edge_t))) return qfalse;
	if (!AAS_WriteAASLump(fp, &header, AASLUMP_EDGEINDEX, aasworld.edgeindex,
		aasworld.edgeindexsize * sizeof(aas_edgeindex_t))) return qfalse;
	if (!AAS_WriteAASLump(fp, &header, AASLUMP_FACES, aasworld.faces,
		aasworld.numfaces * sizeof(aas_face_t))) return qfalse;
	if (!AAS_WriteAASLump(fp, &header, AASLUMP_FACEINDEX, aasworld.faceindex,
		aasworld.faceindexsize * sizeof(aas_faceindex_t))) return qfalse;
	if (!AAS_WriteAASLump(fp, &header, AASLUMP_AREAS, aasworld.areas,
		aasworld.numareas * sizeof(aas_area_t))) return qfalse;
	if (!AAS_WriteAASLump(fp, &header, AASLUMP_AREASETTINGS, aasworld.areasettings,
		aasworld.numareasettings * sizeof(aas_areasettings_t))) return qfalse;
	if (!AAS_WriteAASLump(fp, &header, AASLUMP_REACHABILITY, aasworld.reachability,
		aasworld.reachabilitysize * sizeof(aas_reachability_t))) return qfalse;
	if (!AAS_WriteAASLump(fp, &header, AASLUMP_NODES, aasworld.nodes,
		aasworld.numnodes * sizeof(aas_node_t))) return qfalse;
	if (!AAS_WriteAASLump(fp, &header, AASLUMP_PORTALS, aasworld.portals,
		aasworld.numportals * sizeof(aas_portal_t))) return qfalse;
	if (!AAS_WriteAASLump(fp, &header, AASLUMP_PORTALINDEX, aasworld.portalindex,
		aasworld.portalindexsize * sizeof(aas_portalindex_t))) return qfalse;
	if (!AAS_WriteAASLump(fp, &header, AASLUMP_CLUSTERS, aasworld.clusters,
		aasworld.numclusters * sizeof(aas_cluster_t))) return qfalse;
	//rewrite the header with the added lumps
	botimport.FS_Seek(fp, 0, FS_SEEK_SET);
	AAS_DData((unsigned char *) &header + 8, sizeof(aas_header_t) - 8);
	botimport.FS_Write(&header, sizeof(aas_header_t), fp);
	//close the file
	botimport.FS_FCloseFile(fp);
	return qtrue;
} //end of the function AAS_WriteAASFile