tr_bsp.c

3D 游戏界的大牛人 John Carmack 终于放出了 Q3 的源代码

				//
					v1 = grid1->verts[k + offset1].xyz;
					v2 = grid2->verts[l + offset2].xyz;
					if ( fabs(v1[0] - v2[0]) > .1)
						continue;
					if ( fabs(v1[1] - v2[1]) > .1)
						continue;
					if ( fabs(v1[2] - v2[2]) > .1)
						continue;

					v1 = grid1->verts[k - 2 + offset1].xyz;
					v2 = grid2->verts[l + 1 + offset2].xyz;
					if ( fabs(v1[0] - v2[0]) > .1)
						continue;
					if ( fabs(v1[1] - v2[1]) > .1)
						continue;
					if ( fabs(v1[2] - v2[2]) > .1)
						continue;
					//
					v1 = grid2->verts[l + offset2].xyz;
					v2 = grid2->verts[(l + 1) + offset2].xyz;
					if ( fabs(v1[0] - v2[0]) < .01 &&
							fabs(v1[1] - v2[1]) < .01 &&
							fabs(v1[2] - v2[2]) < .01)
						continue;
					//
					//ri.Printf( PRINT_ALL, "found highest LoD crack between two patches\n" );
					// insert column into grid2 right after after column l
					if (m) row = grid2->height-1;
					else row = 0;
					grid2 = R_GridInsertColumn( grid2, l+1, row,
										grid1->verts[k - 1 + offset1].xyz, grid1->widthLodError[k+1]);
					grid2->lodStitched = qfalse;
					s_worldData.surfaces[grid2num].data = (void *) grid2;
					return qtrue;
				}
			}
			for (m = 0; m < 2; m++) {

				if (grid2->height >= MAX_GRID_SIZE)
					break;
				if (m) offset2 = grid2->width-1;
				else offset2 = 0;
				for ( l = 0; l < grid2->height-1; l++) {
				//
					v1 = grid1->verts[k + offset1].xyz;
					v2 = grid2->verts[grid2->width * l + offset2].xyz;
					if ( fabs(v1[0] - v2[0]) > .1)
						continue;
					if ( fabs(v1[1] - v2[1]) > .1)
						continue;
					if ( fabs(v1[2] - v2[2]) > .1)
						continue;

					v1 = grid1->verts[k - 2 + offset1].xyz;
					v2 = grid2->verts[grid2->width * (l + 1) + offset2].xyz;
					if ( fabs(v1[0] - v2[0]) > .1)
						continue;
					if ( fabs(v1[1] - v2[1]) > .1)
						continue;
					if ( fabs(v1[2] - v2[2]) > .1)
						continue;
					//
					v1 = grid2->verts[grid2->width * l + offset2].xyz;
					v2 = grid2->verts[grid2->width * (l + 1) + offset2].xyz;
					if ( fabs(v1[0] - v2[0]) < .01 &&
							fabs(v1[1] - v2[1]) < .01 &&
							fabs(v1[2] - v2[2]) < .01)
						continue;
					//
					//ri.Printf( PRINT_ALL, "found highest LoD crack between two patches\n" );
					// insert row into grid2 right after after row l
					if (m) column = grid2->width-1;
					else column = 0;
					grid2 = R_GridInsertRow( grid2, l+1, column,
										grid1->verts[k - 1 + offset1].xyz, grid1->widthLodError[k+1]);
					if (!grid2)
						break;
					grid2->lodStitched = qfalse;
					s_worldData.surfaces[grid2num].data = (void *) grid2;
					return qtrue;
				}
			}
		}
	}
	for (n = 0; n < 2; n++) {
		//
		if (n) offset1 = grid1->width-1;
		else offset1 = 0;
		if (R_MergedHeightPoints(grid1, offset1))
			continue;
		for (k = grid1->height-1; k > 1; k -= 2) {
			for (m = 0; m < 2; m++) {

				if ( grid2->width >= MAX_GRID_SIZE )
					break;
				if (m) offset2 = (grid2->height-1) * grid2->width;
				else offset2 = 0;
				for ( l = 0; l < grid2->width-1; l++) {
				//
					v1 = grid1->verts[grid1->width * k + offset1].xyz;
					v2 = grid2->verts[l + offset2].xyz;
					if ( fabs(v1[0] - v2[0]) > .1)
						continue;
					if ( fabs(v1[1] - v2[1]) > .1)
						continue;
					if ( fabs(v1[2] - v2[2]) > .1)
						continue;

					v1 = grid1->verts[grid1->width * (k - 2) + offset1].xyz;
					v2 = grid2->verts[l + 1 + offset2].xyz;
					if ( fabs(v1[0] - v2[0]) > .1)
						continue;
					if ( fabs(v1[1] - v2[1]) > .1)
						continue;
					if ( fabs(v1[2] - v2[2]) > .1)
						continue;
					//
					v1 = grid2->verts[l + offset2].xyz;
					v2 = grid2->verts[(l + 1) + offset2].xyz;
					if ( fabs(v1[0] - v2[0]) < .01 &&
							fabs(v1[1] - v2[1]) < .01 &&
							fabs(v1[2] - v2[2]) < .01)
						continue;
					//
					//ri.Printf( PRINT_ALL, "found highest LoD crack between two patches\n" );
					// insert column into grid2 right after after column l
					if (m) row = grid2->height-1;
					else row = 0;
					grid2 = R_GridInsertColumn( grid2, l+1, row,
										grid1->verts[grid1->width * (k - 1) + offset1].xyz, grid1->heightLodError[k+1]);
					grid2->lodStitched = qfalse;
					s_worldData.surfaces[grid2num].data = (void *) grid2;
					return qtrue;
				}
			}
			for (m = 0; m < 2; m++) {

				if (grid2->height >= MAX_GRID_SIZE)
					break;
				if (m) offset2 = grid2->width-1;
				else offset2 = 0;
				for ( l = 0; l < grid2->height-1; l++) {
				//
					v1 = grid1->verts[grid1->width * k + offset1].xyz;
					v2 = grid2->verts[grid2->width * l + offset2].xyz;
					if ( fabs(v1[0] - v2[0]) > .1)
						continue;
					if ( fabs(v1[1] - v2[1]) > .1)
						continue;
					if ( fabs(v1[2] - v2[2]) > .1)
						continue;

					v1 = grid1->verts[grid1->width * (k - 2) + offset1].xyz;
					v2 = grid2->verts[grid2->width * (l + 1) + offset2].xyz;
					if ( fabs(v1[0] - v2[0]) > .1)
						continue;
					if ( fabs(v1[1] - v2[1]) > .1)
						continue;
					if ( fabs(v1[2] - v2[2]) > .1)
						continue;
					//
					v1 = grid2->verts[grid2->width * l + offset2].xyz;
					v2 = grid2->verts[grid2->width * (l + 1) + offset2].xyz;
					if ( fabs(v1[0] - v2[0]) < .01 &&
							fabs(v1[1] - v2[1]) < .01 &&
							fabs(v1[2] - v2[2]) < .01)
						continue;
					//
					//ri.Printf( PRINT_ALL, "found highest LoD crack between two patches\n" );
					// insert row into grid2 right after after row l
					if (m) column = grid2->width-1;
					else column = 0;
					grid2 = R_GridInsertRow( grid2, l+1, column,
										grid1->verts[grid1->width * (k - 1) + offset1].xyz, grid1->heightLodError[k+1]);
					grid2->lodStitched = qfalse;
					s_worldData.surfaces[grid2num].data = (void *) grid2;
					return qtrue;
				}
			}
		}
	}
	return qfalse;
}

/*
===============
R_TryStitchPatch

This function will try to stitch patches in the same LoD group together for the highest LoD.

Only single missing vertice cracks will be fixed.

Vertices will be joined at the patch side a crack is first found, at the other side
of the patch (on the same row or column) the vertices will not be joined and cracks
might still appear at that side.
===============
*/
int R_TryStitchingPatch( int grid1num ) {
	int j, numstitches;
	srfGridMesh_t *grid1, *grid2;

	numstitches = 0;
	grid1 = (srfGridMesh_t *) s_worldData.surfaces[grid1num].data;
	for ( j = 0; j < s_worldData.numsurfaces; j++ ) {
		//
		grid2 = (srfGridMesh_t *) s_worldData.surfaces[j].data;
		// if this surface is not a grid
		if ( grid2->surfaceType != SF_GRID ) continue;
		// grids in the same LOD group should have the exact same lod radius
		if ( grid1->lodRadius != grid2->lodRadius ) continue;
		// grids in the same LOD group should have the exact same lod origin
		if ( grid1->lodOrigin[0] != grid2->lodOrigin[0] ) continue;
		if ( grid1->lodOrigin[1] != grid2->lodOrigin[1] ) continue;
		if ( grid1->lodOrigin[2] != grid2->lodOrigin[2] ) continue;
		//
		while (R_StitchPatches(grid1num, j))
		{
			numstitches++;
		}
	}
	return numstitches;
}

/*
===============
R_StitchAllPatches
===============
*/
void R_StitchAllPatches( void ) {
	int i, stitched, numstitches;
	srfGridMesh_t *grid1;

	numstitches = 0;
	do
	{
		stitched = qfalse;
		for ( i = 0; i < s_worldData.numsurfaces; i++ ) {
			//
			grid1 = (srfGridMesh_t *) s_worldData.surfaces[i].data;
			// if this surface is not a grid
			if ( grid1->surfaceType != SF_GRID )
				continue;
			//
			if ( grid1->lodStitched )
				continue;
			//
			grid1->lodStitched = qtrue;
			stitched = qtrue;
			//
			numstitches += R_TryStitchingPatch( i );
		}
	}
	while (stitched);
	ri.Printf( PRINT_ALL, "stitched %d LoD cracks\n", numstitches );
}

/*
===============
R_MovePatchSurfacesToHunk
===============
*/
void R_MovePatchSurfacesToHunk(void) {
	int i, size;
	srfGridMesh_t *grid, *hunkgrid;

	for ( i = 0; i < s_worldData.numsurfaces; i++ ) {
		//
		grid = (srfGridMesh_t *) s_worldData.surfaces[i].data;
		// if this surface is not a grid
		if ( grid->surfaceType != SF_GRID )
			continue;
		//
		size = (grid->width * grid->height - 1) * sizeof( drawVert_t ) + sizeof( *grid );
		hunkgrid = ri.Hunk_Alloc( size, h_low );
		Com_Memcpy(hunkgrid, grid, size);

		hunkgrid->widthLodError = ri.Hunk_Alloc( grid->width * 4, h_low );
		Com_Memcpy( hunkgrid->widthLodError, grid->widthLodError, grid->width * 4 );

		hunkgrid->heightLodError = ri.Hunk_Alloc( grid->height * 4, h_low );
		Com_Memcpy( grid->heightLodError, grid->heightLodError, grid->height * 4 );

		R_FreeSurfaceGridMesh( grid );

		s_worldData.surfaces[i].data = (void *) hunkgrid;
	}
}

/*
===============
R_LoadSurfaces
===============
*/
static	void R_LoadSurfaces( lump_t *surfs, lump_t *verts, lump_t *indexLump ) {
	dsurface_t	*in;
	msurface_t	*out;
	drawVert_t	*dv;
	int			*indexes;
	int			count;
	int			numFaces, numMeshes, numTriSurfs, numFlares;
	int			i;

	numFaces = 0;
	numMeshes = 0;
	numTriSurfs = 0;
	numFlares = 0;

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

	dv = (void *)(fileBase + verts->fileofs);
	if (verts->filelen % sizeof(*dv))
		ri.Error (ERR_DROP, "LoadMap: funny lump size in %s",s_worldData.name);

	indexes = (void *)(fileBase + indexLump->fileofs);
	if ( indexLump->filelen % sizeof(*indexes))
		ri.Error (ERR_DROP, "LoadMap: funny lump size in %s",s_worldData.name);

	out = ri.Hunk_Alloc ( count * sizeof(*out), h_low );	

	s_worldData.surfaces = out;
	s_worldData.numsurfaces = count;

	for ( i = 0 ; i < count ; i++, in++, out++ ) {
		switch ( LittleLong( in->surfaceType ) ) {
		case MST_PATCH:
			ParseMesh ( in, dv, out );
			numMeshes++;
			break;
		case MST_TRIANGLE_SOUP:
			ParseTriSurf( in, dv, out, indexes );
			numTriSurfs++;
			break;
		case MST_PLANAR:
			ParseFace( in, dv, out, indexes );
			numFaces++;
			break;
		case MST_FLARE:
			ParseFlare( in, dv, out, indexes );
			numFlares++;
			break;
		default:
			ri.Error( ERR_DROP, "Bad surfaceType" );
		}
	}

#ifdef PATCH_STITCHING
	R_StitchAllPatches();
#endif

	R_FixSharedVertexLodError();

#ifdef PATCH_STITCHING
	R_MovePatchSurfacesToHunk();
#endif

	ri.Printf( PRINT_ALL, "...loaded %d faces, %i meshes, %i trisurfs, %i flares\n", 
		numFaces, numMeshes, numTriSurfs, numFlares );
}



/*
=================
R_LoadSubmodels
=================
*/
static	void R_LoadSubmodels( lump_t *l ) {
	dmodel_t	*in;
	bmodel_t	*out;
	int			i, j, count;

	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);

	s_worldData.bmodels = out = ri.Hunk_Alloc( count * sizeof(*out), h_low );

	for ( i=0 ; i<count ; i++, in++, out++ ) {
		model_t *model;

		model = R_AllocModel();

		assert( model != NULL );			// this should never happen

		model->type = MOD_BRUSH;
		model->bmodel = out;
		Com_sprintf( model->name, sizeof( model->name ), "*%d", i );

		for (j=0 ; j<3 ; j++) {
			out->bounds[0][j] = LittleFloat (in->mins[j]);
			out->bounds[1][j] = LittleFloat (in->maxs[j]);
		}

		out->firstSurface = s_worldData.surfaces + LittleLong( in->firstSurface );
		out->numSurfaces = LittleLong( in->numSurfaces );
	}
}



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

/*
=================
R_SetParent
=================
*/
static	void R_SetParent (mnode_t *node, mnode_t *parent)
{
	node->parent = parent;
	if (node->contents != -1)
		return;
	R_SetParent (node->children[0], node);
	R_SetParent (node->children[1], node);
}

/*
=================
R_LoadNodesAndLeafs
=================
*/
static	void R_LoadNodesAndLeafs (lump_t *nodeLump, lump_t *leafLump) {
	int			i, j, p;
	dnode_t		*in;
	dleaf_t		*inLeaf;
	mnode_t 	*out;
	int			numNodes, numLeafs;

	in = (void *)(fileBase + nodeLump->fileofs);
	if (nodeLump->filelen % sizeof(dnode_t) ||
		leafLump->filelen % sizeof(dleaf_t) ) {
		ri.Error (ERR_DROP, "LoadMap: funny lump size in %s",s_worldData.name);
	}
	numNodes = nodeLump->filelen / sizeof(dnode_t);
	numLeafs = leafLump->filelen / sizeof(dleaf_t);

	out = ri.Hunk_Alloc ( (numNodes + numLeafs) * sizeof(*out), h_low);	

	s_worldData.nodes = out;
	s_worldData.numnodes = numNodes + numLeafs;
	s_worldData.numDecisionNodes = numNodes;

	// load nodes
	for ( i=0 ; i<numNodes; i++, in++, out++)
	{
		for (j=0 ; j<3 ; j++)
		{
			out->mins[j] = LittleLong (in->mins[j]);
			out->maxs[j] = LittleLong (in->maxs[j]);
		}
	
		p = LittleLong(in->planeNum);
		out->plane = s_worldData.planes + p;

		out->contents = CONTENTS_NODE;	// differentiate from leafs

		for (j=0 ; j<2 ; j++)
		{
			p = LittleLong (in->children[j]);
			if (p >= 0)
				out->children[j] = s_worldData.nodes + p;