/*
===============
R_GridInsertRow
===============
*/
srfGridMesh_t *R_GridInsertRow(srfGridMesh_t *grid, int row, int column, vec3_t point, float loderror)
{
int i, j;
int width, height, oldheight;
MAC_STATIC drawVert_t ctrl[MAX_GRID_SIZE][MAX_GRID_SIZE];
float errorTable[2][MAX_GRID_SIZE];
float lodRadius;
vec3_t lodOrigin;
oldheight = 0;
width = grid->width;
height = grid->height + 1;
if (height > MAX_GRID_SIZE)
{
return NULL;
}
for (i = 0; i < height; i++)
{
if (i == row)
{
//insert new row
for (j = 0; j < grid->width; j++)
{
LerpDrawVert(&grid->verts[(i - 1) * grid->width + j], &grid->verts[i * grid->width + j], &ctrl[i][j]);
if (j == column)
{
VectorCopy(point, ctrl[i][j].xyz);
}
}
errorTable[1][i] = loderror;
continue;
}
errorTable[1][i] = grid->heightLodError[oldheight];
for (j = 0; j < grid->width; j++)
{
ctrl[i][j] = grid->verts[oldheight * grid->width + j];
}
oldheight++;
}
for (j = 0; j < grid->width; j++)
{
errorTable[0][j] = grid->widthLodError[j];
}
// put all the aproximating points on the curve
//PutPointsOnCurve( ctrl, width, height );
// calculate normals
MakeMeshNormals(width, height, ctrl);
VectorCopy(grid->lodOrigin, lodOrigin);
lodRadius = grid->lodRadius;
// free the old grid
R_FreeSurfaceGridMesh(grid);
// create a new grid
grid = R_CreateSurfaceGridMesh(width, height, ctrl, errorTable);
grid->lodRadius = lodRadius;
VectorCopy(lodOrigin, grid->lodOrigin);
return grid;
}
/*
* R_GridInsertRow
*/
srfGridMesh_t *
R_GridInsertRow(srfGridMesh_t *grid, int row, int column, Vec3 point, float loderror)
{
int i, j;
int width, height, oldheight;
Drawvert ctrl[MAX_GRID_SIZE][MAX_GRID_SIZE];
float errorTable[2][MAX_GRID_SIZE];
float lodRadius;
Vec3 lodOrigin;
oldheight = 0;
width = grid->width;
height = grid->height + 1;
if(height > MAX_GRID_SIZE)
return NULL;
for(i = 0; i < height; i++){
if(i == row){
/* insert new row */
for(j = 0; j < grid->width; j++){
LerpDrawVert(&grid->verts[(i-1) * grid->width + j],
&grid->verts[i * grid->width + j], &ctrl[i][j]);
if(j == column)
copyv3(point, ctrl[i][j].xyz);
}
errorTable[1][i] = loderror;
continue;
}
errorTable[1][i] = grid->heightLodError[oldheight];
for(j = 0; j < grid->width; j++)
ctrl[i][j] = grid->verts[oldheight * grid->width + j];
oldheight++;
}
for(j = 0; j < grid->width; j++)
errorTable[0][j] = grid->widthLodError[j];
/* put all the aproximating points on the curve
* PutPointsOnCurve( ctrl, width, height );
* calculate normals */
MakeMeshNormals(width, height, ctrl);
copyv3(grid->lodOrigin, lodOrigin);
lodRadius = grid->lodRadius;
/* free the old grid */
R_FreeSurfaceGridMesh(grid);
/* create a new grid */
grid = R_CreateSurfaceGridMesh(width, height, ctrl, errorTable);
grid->lodRadius = lodRadius;
copyv3(lodOrigin, grid->lodOrigin);
return grid;
}
bool R_GridInsertRow( class idSurfaceGrid* grid, int row, int column, const idVec3& point, float loderror ) {
int oldheight = 0;
int width = grid->width;
int height = grid->height + 1;
if ( height > MAX_GRID_SIZE ) {
return false;
}
idWorldVertex ctrl[ MAX_GRID_SIZE ][ MAX_GRID_SIZE ];
float errorTable[ 2 ][ MAX_GRID_SIZE ];
for ( int i = 0; i < height; i++ ) {
if ( i == row ) {
//insert new row
for ( int j = 0; j < grid->width; j++ ) {
ctrl[ i ][ j ] = LerpDrawVert( grid->vertexes[ ( i - 1 ) * grid->width + j ], grid->vertexes[ i * grid->width + j ] );
if ( j == column ) {
ctrl[ i ][ j ].xyz = point;
}
}
errorTable[ 1 ][ i ] = loderror;
continue;
}
errorTable[ 1 ][ i ] = grid->heightLodError[ oldheight ];
for ( int j = 0; j < grid->width; j++ ) {
ctrl[ i ][ j ] = grid->vertexes[ oldheight * grid->width + j ];
}
oldheight++;
}
for ( int j = 0; j < grid->width; j++ ) {
errorTable[ 0 ][ j ] = grid->widthLodError[ j ];
}
// put all the aproximating points on the curve
//PutPointsOnCurve( ctrl, width, height );
// calculate normals
MakeMeshNormals( width, height, ctrl );
// free the old grid
R_FreeSurfaceGridMeshAndVertexes( grid );
// create a new grid
R_CreateSurfaceGridMesh( grid, width, height, ctrl, errorTable );
return true;
}
/*
=================
R_SubdividePatchToGrid
=================
*/
srfGridMesh_t *R_SubdividePatchToGrid(int width, int height,
drawVert_t points[MAX_PATCH_SIZE * MAX_PATCH_SIZE])
{
int i, j, k, l;
drawVert_t prev, next, mid;
float len, maxLen;
int dir;
int t;
MAC_STATIC drawVert_t ctrl[MAX_GRID_SIZE][MAX_GRID_SIZE];
float errorTable[2][MAX_GRID_SIZE];
for (i = 0 ; i < width ; i++)
{
for (j = 0 ; j < height ; j++)
{
ctrl[j][i] = points[j * width + i];
}
}
for (dir = 0 ; dir < 2 ; dir++)
{
for (j = 0 ; j < MAX_GRID_SIZE ; j++)
{
errorTable[dir][j] = 0;
}
// horizontal subdivisions
for (j = 0 ; j + 2 < width ; j += 2)
{
// check subdivided midpoints against control points
// FIXME: also check midpoints of adjacent patches against the control points
// this would basically stitch all patches in the same LOD group together.
maxLen = 0;
for (i = 0 ; i < height ; i++)
{
vec3_t midxyz;
vec3_t dir;
vec3_t projected;
float d;
// calculate the point on the curve
for (l = 0 ; l < 3 ; l++)
{
midxyz[l] = (ctrl[i][j].xyz[l] + ctrl[i][j + 1].xyz[l] * 2
+ ctrl[i][j + 2].xyz[l]) * 0.25f;
}
// see how far off the line it is
// using dist-from-line will not account for internal
// texture warping, but it gives a lot less polygons than
// dist-from-midpoint
VectorSubtract(midxyz, ctrl[i][j].xyz, midxyz);
VectorSubtract(ctrl[i][j + 2].xyz, ctrl[i][j].xyz, dir);
VectorNormalize(dir);
d = DotProduct(midxyz, dir);
VectorScale(dir, d, projected);
VectorSubtract(midxyz, projected, midxyz);
len = VectorLengthSquared(midxyz); // we will do the sqrt later
if (len > maxLen)
{
maxLen = len;
}
}
maxLen = sqrt(maxLen);
// if all the points are on the lines, remove the entire columns
if (maxLen < 0.1f)
{
errorTable[dir][j + 1] = 999;
continue;
}
// see if we want to insert subdivided columns
if (width + 2 > MAX_GRID_SIZE)
{
errorTable[dir][j + 1] = 1.0f / maxLen;
continue; // can't subdivide any more
}
if (maxLen <= r_subdivisions->value)
{
errorTable[dir][j + 1] = 1.0f / maxLen;
continue; // didn't need subdivision
}
errorTable[dir][j + 2] = 1.0f / maxLen;
// insert two columns and replace the peak
width += 2;
for (i = 0 ; i < height ; i++)
{
LerpDrawVert(&ctrl[i][j], &ctrl[i][j + 1], &prev);
LerpDrawVert(&ctrl[i][j + 1], &ctrl[i][j + 2], &next);
LerpDrawVert(&prev, &next, &mid);
for (k = width - 1 ; k > j + 3 ; k--)
{
ctrl[i][k] = ctrl[i][k - 2];
}
ctrl[i][j + 1] = prev;
ctrl[i][j + 2] = mid;
ctrl[i][j + 3] = next;
}
// back up and recheck this set again, it may need more subdivision
j -= 2;
}
Transpose(width, height, ctrl);
t = width;
width = height;
height = t;
}
// put all the aproximating points on the curve
PutPointsOnCurve(ctrl, width, height);
// cull out any rows or columns that are colinear
for (i = 1 ; i < width - 1 ; i++)
{
if (errorTable[0][i] != 999)
{
continue;
}
for (j = i + 1 ; j < width ; j++)
{
for (k = 0 ; k < height ; k++)
{
ctrl[k][j - 1] = ctrl[k][j];
}
errorTable[0][j - 1] = errorTable[0][j];
}
width--;
}
for (i = 1 ; i < height - 1 ; i++)
{
if (errorTable[1][i] != 999)
{
continue;
}
for (j = i + 1 ; j < height ; j++)
{
for (k = 0 ; k < width ; k++)
{
ctrl[j - 1][k] = ctrl[j][k];
}
errorTable[1][j - 1] = errorTable[1][j];
}
height--;
}
// flip for longest tristrips as an optimization
// the results should be visually identical with or
// without this step
if (height > width)
{
Transpose(width, height, ctrl);
InvertErrorTable(errorTable, width, height);
t = width;
width = height;
height = t;
InvertCtrl(width, height, ctrl);
}
// calculate normals
MakeMeshNormals(width, height, ctrl);
return R_CreateSurfaceGridMesh(width, height, ctrl, errorTable);
}
srfGridMesh_t *R_GridInsertRow(srfGridMesh_t *grid, int row, int column, vec3_t point, float loderror)
{
int i, j;
int width = grid->width, height = grid->height + 1, oldheight = 0;
static srfVert_t ctrl[MAX_GRID_SIZE][MAX_GRID_SIZE];
float errorTable[2][MAX_GRID_SIZE];
float lodRadius;
vec3_t lodOrigin;
int numTriangles;
static srfTriangle_t triangles[SHADER_MAX_TRIANGLES];
if (height > MAX_GRID_SIZE)
{
return NULL;
}
for (i = 0; i < height; i++)
{
if (i == row)
{
//insert new row
for (j = 0; j < grid->width; j++)
{
LerpSurfaceVert(&grid->verts[(i - 1) * grid->width + j], &grid->verts[i * grid->width + j], &ctrl[i][j]);
if (j == column)
{
VectorCopy(point, ctrl[i][j].xyz);
}
}
errorTable[1][i] = loderror;
continue;
}
errorTable[1][i] = grid->heightLodError[oldheight];
for (j = 0; j < grid->width; j++)
{
ctrl[i][j] = grid->verts[oldheight * grid->width + j];
}
oldheight++;
}
for (j = 0; j < grid->width; j++)
{
errorTable[0][j] = grid->widthLodError[j];
}
// put all the aproximating points on the curve
//PutPointsOnCurve( ctrl, width, height );
// calculate triangles
numTriangles = MakeMeshTriangles(width, height, ctrl, triangles);
// calculate normals
MakeMeshNormals(width, height, ctrl);
MakeMeshTangentVectors(width, height, ctrl, numTriangles, triangles);
// calculate tangent spaces
//MakeTangentSpaces(width, height, ctrl, numTriangles, triangles);
VectorCopy(grid->lodOrigin, lodOrigin);
lodRadius = grid->lodRadius;
// free the old grid
R_FreeSurfaceGridMesh(grid);
// create a new grid
grid = R_CreateSurfaceGridMesh(width, height, ctrl, errorTable, numTriangles, triangles);
grid->lodRadius = lodRadius;
VectorCopy(lodOrigin, grid->lodOrigin);
return grid;
}
/*
* R_SubdividePatchToGrid
*/
srfGridMesh_t *
R_SubdividePatchToGrid(int width, int height,
Drawvert points[MAX_PATCH_SIZE*MAX_PATCH_SIZE])
{
int i, j, k, l;
drawVert_t_cleared(prev);
drawVert_t_cleared(next);
drawVert_t_cleared(mid);
float len, maxLen;
int dir;
int t;
Drawvert ctrl[MAX_GRID_SIZE][MAX_GRID_SIZE];
float errorTable[2][MAX_GRID_SIZE];
for(i = 0; i < width; i++)
for(j = 0; j < height; j++)
ctrl[j][i] = points[j*width+i];
for(dir = 0; dir < 2; dir++){
for(j = 0; j < MAX_GRID_SIZE; j++)
errorTable[dir][j] = 0;
/* horizontal subdivisions */
for(j = 0; j + 2 < width; j += 2){
/* check subdivided midpoints against control points */
/* FIXME: also check midpoints of adjacent patches against the control points
* this would basically stitch all patches in the same LOD group together. */
maxLen = 0;
for(i = 0; i < height; i++){
Vec3 midxyz;
Vec3 midxyz2;
Vec3 dir;
Vec3 projected;
float d;
/* calculate the point on the curve */
for(l = 0; l < 3; l++)
midxyz[l] = (ctrl[i][j].xyz[l] + ctrl[i][j+1].xyz[l] * 2
+ ctrl[i][j+2].xyz[l]) * 0.25f;
/* see how far off the line it is
* using dist-from-line will not account for internal
* texture warping, but it gives a lot less polygons than
* dist-from-midpoint */
subv3(midxyz, ctrl[i][j].xyz, midxyz);
subv3(ctrl[i][j+2].xyz, ctrl[i][j].xyz, dir);
normv3(dir);
d = dotv3(midxyz, dir);
scalev3(dir, d, projected);
subv3(midxyz, projected, midxyz2);
len = lensqrv3(midxyz2); /* we will do the sqrt later */
if(len > maxLen){
maxLen = len;
}
}
maxLen = sqrt(maxLen);
/* if all the points are on the lines, remove the entire columns */
if(maxLen < 0.1f){
errorTable[dir][j+1] = 999;
continue;
}
/* see if we want to insert subdivided columns */
if(width + 2 > MAX_GRID_SIZE){
errorTable[dir][j+1] = 1.0f/maxLen;
continue; /* can't subdivide any more */
}
if(maxLen <= r_subdivisions->value){
errorTable[dir][j+1] = 1.0f/maxLen;
continue; /* didn't need subdivision */
}
errorTable[dir][j+2] = 1.0f/maxLen;
/* insert two columns and replace the peak */
width += 2;
for(i = 0; i < height; i++){
LerpDrawVert(&ctrl[i][j], &ctrl[i][j+1], &prev);
LerpDrawVert(&ctrl[i][j+1], &ctrl[i][j+2], &next);
LerpDrawVert(&prev, &next, &mid);
for(k = width - 1; k > j + 3; k--)
ctrl[i][k] = ctrl[i][k-2];
ctrl[i][j + 1] = prev;
ctrl[i][j + 2] = mid;
ctrl[i][j + 3] = next;
}
/* back up and recheck this set again, it may need more subdivision */
j -= 2;
}
Transpose(width, height, ctrl);
t = width;
width = height;
height = t;
}
/* put all the aproximating points on the curve */
PutPointsOnCurve(ctrl, width, height);
/* cull out any rows or columns that are colinear */
for(i = 1; i < width-1; i++){
if(errorTable[0][i] != 999){
continue;
}
for(j = i+1; j < width; j++){
for(k = 0; k < height; k++)
ctrl[k][j-1] = ctrl[k][j];
errorTable[0][j-1] = errorTable[0][j];
}
width--;
}
for(i = 1; i < height-1; i++){
if(errorTable[1][i] != 999){
continue;
}
for(j = i+1; j < height; j++){
for(k = 0; k < width; k++)
ctrl[j-1][k] = ctrl[j][k];
errorTable[1][j-1] = errorTable[1][j];
}
height--;
}
#if 1
/* flip for longest tristrips as an optimization
* the results should be visually identical with or
* without this step */
if(height > width){
Transpose(width, height, ctrl);
InvertErrorTable(errorTable, width, height);
t = width;
width = height;
height = t;
InvertCtrl(width, height, ctrl);
}
#endif
/* calculate normals */
MakeMeshNormals(width, height, ctrl);
return R_CreateSurfaceGridMesh(width, height, ctrl, errorTable);
}
void R_SubdividePatchToGrid( idSurfaceGrid* surf, int width, int height, idWorldVertex points[ MAX_PATCH_SIZE * MAX_PATCH_SIZE ] ) {
idWorldVertex ctrl[ MAX_GRID_SIZE ][ MAX_GRID_SIZE ];
for ( int i = 0; i < width; i++ ) {
for ( int j = 0; j < height; j++ ) {
ctrl[ j ][ i ] = points[ j * width + i ];
}
}
float errorTable[ 2 ][ MAX_GRID_SIZE ];
for ( int dir = 0; dir < 2; dir++ ) {
for ( int j = 0; j < MAX_GRID_SIZE; j++ ) {
errorTable[ dir ][ j ] = 0;
}
// horizontal subdivisions
for ( int j = 0; j + 2 < width; j += 2 ) {
// check subdivided midpoints against control points
// FIXME: also check midpoints of adjacent patches against the control points
// this would basically stitch all patches in the same LOD group together.
float maxLen = 0;
for ( int i = 0; i < height; i++ ) {
// calculate the point on the curve
idVec3 midxyz = ( ctrl[ i ][ j ].xyz + ctrl[ i ][ j + 1 ].xyz * 2 + ctrl[ i ][ j + 2 ].xyz ) * 0.25f;
// see how far off the line it is
// using dist-from-line will not account for internal
// texture warping, but it gives a lot less polygons than
// dist-from-midpoint
midxyz = midxyz - ctrl[ i ][ j ].xyz;
idVec3 dir = ctrl[ i ][ j + 2 ].xyz - ctrl[ i ][ j ].xyz;
dir.Normalize();
float d = midxyz * dir;
idVec3 projected = dir * d;
idVec3 midxyz2 = midxyz - projected;
float len = midxyz2.LengthSqr(); // we will do the sqrt later
if ( len > maxLen ) {
maxLen = len;
}
}
maxLen = sqrt( maxLen );
// if all the points are on the lines, remove the entire columns
if ( maxLen < 0.1f ) {
errorTable[ dir ][ j + 1 ] = 999;
continue;
}
// see if we want to insert subdivided columns
if ( width + 2 > MAX_GRID_SIZE ) {
errorTable[ dir ][ j + 1 ] = 1.0f / maxLen;
continue; // can't subdivide any more
}
if ( maxLen <= r_subdivisions->value ) {
errorTable[ dir ][ j + 1 ] = 1.0f / maxLen;
continue; // didn't need subdivision
}
errorTable[ dir ][ j + 2 ] = 1.0f / maxLen;
// insert two columns and replace the peak
width += 2;
for ( int i = 0; i < height; i++ ) {
idWorldVertex prev = LerpDrawVert( ctrl[ i ][ j ], ctrl[ i ][ j + 1 ] );
idWorldVertex next = LerpDrawVert( ctrl[ i ][ j + 1 ], ctrl[ i ][ j + 2 ] );
idWorldVertex mid = LerpDrawVert( prev, next );
for ( int k = width - 1; k > j + 3; k-- ) {
ctrl[ i ][ k ] = ctrl[ i ][ k - 2 ];
}
ctrl[ i ][ j + 1 ] = prev;
ctrl[ i ][ j + 2 ] = mid;
ctrl[ i ][ j + 3 ] = next;
}
// back up and recheck this set again, it may need more subdivision
j -= 2;
}
Transpose( width, height, ctrl );
int t = width;
width = height;
height = t;
}
// put all the aproximating points on the curve
PutPointsOnCurve( ctrl, width, height );
// cull out any rows or columns that are colinear
for ( int i = 1; i < width - 1; i++ ) {
if ( errorTable[ 0 ][ i ] != 999 ) {
continue;
}
for ( int j = i + 1; j < width; j++ ) {
for ( int k = 0; k < height; k++ ) {
ctrl[ k ][ j - 1 ] = ctrl[ k ][ j ];
}
errorTable[ 0 ][ j - 1 ] = errorTable[ 0 ][ j ];
}
width--;
}
for ( int i = 1; i < height - 1; i++ ) {
if ( errorTable[ 1 ][ i ] != 999 ) {
continue;
}
for ( int j = i + 1; j < height; j++ ) {
for ( int k = 0; k < width; k++ ) {
ctrl[ j - 1 ][ k ] = ctrl[ j ][ k ];
}
errorTable[ 1 ][ j - 1 ] = errorTable[ 1 ][ j ];
}
height--;
}
#if 1
// flip for longest tristrips as an optimization
// the results should be visually identical with or
// without this step
if ( height > width ) {
Transpose( width, height, ctrl );
InvertErrorTable( errorTable, width, height );
int t = width;
width = height;
height = t;
InvertCtrl( width, height, ctrl );
}
#endif
// calculate normals
MakeMeshNormals( width, height, ctrl );
R_CreateSurfaceGridMesh( surf, width, height, ctrl, errorTable );
}
/*
===============
R_GridInsertRow
===============
*/
srfGridMesh_t *R_GridInsertRow( srfGridMesh_t *grid, int row, int column, vec3_t point, float loderror )
{
int i, j;
int width, height, oldheight;
float errorTable[ 2 ][ MAX_GRID_SIZE ];
float lodRadius;
vec3_t lodOrigin;
int numTriangles;
oldheight = 0;
width = grid->width;
height = grid->height + 1;
if ( height > MAX_GRID_SIZE )
{
return nullptr;
}
for ( i = 0; i < height; i++ )
{
if ( i == row )
{
//insert new row
for ( j = 0; j < grid->width; j++ )
{
LerpSurfaceVert( &grid->verts[( i - 1 ) * grid->width + j ], &grid->verts[ i * grid->width + j ], &gridctrl[ i ][ j ] );
if ( j == column )
{
VectorCopy( point, gridctrl[ i ][ j ].xyz );
}
}
errorTable[ 1 ][ i ] = loderror;
continue;
}
errorTable[ 1 ][ i ] = grid->heightLodError[ oldheight ];
for ( j = 0; j < grid->width; j++ )
{
gridctrl[ i ][ j ] = grid->verts[ oldheight * grid->width + j ];
}
oldheight++;
}
for ( j = 0; j < grid->width; j++ )
{
errorTable[ 0 ][ j ] = grid->widthLodError[ j ];
}
// calculate triangles
numTriangles = MakeMeshTriangles( width, height, gridctrl, gridtriangles );
// calculate normals
MakeMeshNormals( width, height, gridctrl );
VectorCopy( grid->lodOrigin, lodOrigin );
lodRadius = grid->lodRadius;
// free the old grid
R_FreeSurfaceGridMesh( grid );
// create a new grid
grid = R_CreateSurfaceGridMesh( width, height, gridctrl, errorTable, numTriangles, gridtriangles );
grid->lodRadius = lodRadius;
VectorCopy( lodOrigin, grid->lodOrigin );
return grid;
}
/*
===============
R_GridInsertColumn
===============
*/
srfGridMesh_t *R_GridInsertColumn(srfGridMesh_t *grid, int column, int row, vec3_t point, float loderror)
{
int i, j;
int width, height, oldwidth;
srfVert_t ctrl[MAX_GRID_SIZE][MAX_GRID_SIZE];
float errorTable[2][MAX_GRID_SIZE];
float lodRadius;
vec3_t lodOrigin;
int numTriangles;
static srfTriangle_t triangles[(MAX_GRID_SIZE - 1) * (MAX_GRID_SIZE - 1) * 2];
oldwidth = 0;
width = grid->width + 1;
if (width > MAX_GRID_SIZE)
{
return NULL;
}
height = grid->height;
for (i = 0; i < width; i++)
{
if (i == column)
{
//insert new column
for (j = 0; j < grid->height; j++)
{
LerpDrawVert(&grid->verts[j * grid->width + i - 1], &grid->verts[j * grid->width + i], &ctrl[j][i]);
if (j == row)
{
VectorCopy(point, ctrl[j][i].xyz);
}
}
errorTable[0][i] = loderror;
continue;
}
errorTable[0][i] = grid->widthLodError[oldwidth];
for (j = 0; j < grid->height; j++)
{
ctrl[j][i] = grid->verts[j * grid->width + oldwidth];
}
oldwidth++;
}
for (j = 0; j < grid->height; j++)
{
errorTable[1][j] = grid->heightLodError[j];
}
// put all the aproximating points on the curve
//PutPointsOnCurve( ctrl, width, height );
// calculate triangles
numTriangles = MakeMeshTriangles(width, height, ctrl, triangles);
// calculate normals
MakeMeshNormals(width, height, ctrl);
VectorCopy(grid->lodOrigin, lodOrigin);
lodRadius = grid->lodRadius;
// free the old grid
R_FreeSurfaceGridMesh(grid);
// create a new grid
grid = R_CreateSurfaceGridMesh(width, height, ctrl, errorTable, numTriangles, triangles);
grid->lodRadius = lodRadius;
VectorCopy(lodOrigin, grid->lodOrigin);
return grid;
}