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-rw-r--r--src/renderer/tr_curve.c627
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diff --git a/src/renderer/tr_curve.c b/src/renderer/tr_curve.c
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+/*
+===========================================================================
+Copyright (C) 1999-2005 Id Software, Inc.
+Copyright (C) 2000-2006 Tim Angus
+
+This file is part of Tremulous.
+
+Tremulous is free software; you can redistribute it
+and/or modify it under the terms of the GNU General Public License as
+published by the Free Software Foundation; either version 2 of the License,
+or (at your option) any later version.
+
+Tremulous is distributed in the hope that it will be
+useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with Tremulous; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+===========================================================================
+*/
+
+#include "tr_local.h"
+
+/*
+
+This file does all of the processing necessary to turn a raw grid of points
+read from the map file into a srfGridMesh_t ready for rendering.
+
+The level of detail solution is direction independent, based only on subdivided
+distance from the true curve.
+
+Only a single entry point:
+
+srfGridMesh_t *R_SubdividePatchToGrid( int width, int height,
+ drawVert_t points[MAX_PATCH_SIZE*MAX_PATCH_SIZE] ) {
+
+*/
+
+
+/*
+============
+LerpDrawVert
+============
+*/
+static void LerpDrawVert( drawVert_t *a, drawVert_t *b, drawVert_t *out ) {
+ out->xyz[0] = 0.5f * (a->xyz[0] + b->xyz[0]);
+ out->xyz[1] = 0.5f * (a->xyz[1] + b->xyz[1]);
+ out->xyz[2] = 0.5f * (a->xyz[2] + b->xyz[2]);
+
+ out->st[0] = 0.5f * (a->st[0] + b->st[0]);
+ out->st[1] = 0.5f * (a->st[1] + b->st[1]);
+
+ out->lightmap[0] = 0.5f * (a->lightmap[0] + b->lightmap[0]);
+ out->lightmap[1] = 0.5f * (a->lightmap[1] + b->lightmap[1]);
+
+ out->color[0] = (a->color[0] + b->color[0]) >> 1;
+ out->color[1] = (a->color[1] + b->color[1]) >> 1;
+ out->color[2] = (a->color[2] + b->color[2]) >> 1;
+ out->color[3] = (a->color[3] + b->color[3]) >> 1;
+}
+
+/*
+============
+Transpose
+============
+*/
+static void Transpose( int width, int height, drawVert_t ctrl[MAX_GRID_SIZE][MAX_GRID_SIZE] ) {
+ int i, j;
+ drawVert_t temp;
+
+ if ( width > height ) {
+ for ( i = 0 ; i < height ; i++ ) {
+ for ( j = i + 1 ; j < width ; j++ ) {
+ if ( j < height ) {
+ // swap the value
+ temp = ctrl[j][i];
+ ctrl[j][i] = ctrl[i][j];
+ ctrl[i][j] = temp;
+ } else {
+ // just copy
+ ctrl[j][i] = ctrl[i][j];
+ }
+ }
+ }
+ } else {
+ for ( i = 0 ; i < width ; i++ ) {
+ for ( j = i + 1 ; j < height ; j++ ) {
+ if ( j < width ) {
+ // swap the value
+ temp = ctrl[i][j];
+ ctrl[i][j] = ctrl[j][i];
+ ctrl[j][i] = temp;
+ } else {
+ // just copy
+ ctrl[i][j] = ctrl[j][i];
+ }
+ }
+ }
+ }
+
+}
+
+
+/*
+=================
+MakeMeshNormals
+
+Handles all the complicated wrapping and degenerate cases
+=================
+*/
+static void MakeMeshNormals( int width, int height, drawVert_t ctrl[MAX_GRID_SIZE][MAX_GRID_SIZE] ) {
+ int i, j, k, dist;
+ vec3_t normal;
+ vec3_t sum;
+ int count = 0;
+ vec3_t base;
+ vec3_t delta;
+ int x, y;
+ drawVert_t *dv;
+ vec3_t around[8], temp;
+ qboolean good[8];
+ qboolean wrapWidth, wrapHeight;
+ float len;
+static int neighbors[8][2] = {
+ {0,1}, {1,1}, {1,0}, {1,-1}, {0,-1}, {-1,-1}, {-1,0}, {-1,1}
+ };
+
+ wrapWidth = qfalse;
+ for ( i = 0 ; i < height ; i++ ) {
+ VectorSubtract( ctrl[i][0].xyz, ctrl[i][width-1].xyz, delta );
+ len = VectorLengthSquared( delta );
+ if ( len > 1.0 ) {
+ break;
+ }
+ }
+ if ( i == height ) {
+ wrapWidth = qtrue;
+ }
+
+ wrapHeight = qfalse;
+ for ( i = 0 ; i < width ; i++ ) {
+ VectorSubtract( ctrl[0][i].xyz, ctrl[height-1][i].xyz, delta );
+ len = VectorLengthSquared( delta );
+ if ( len > 1.0 ) {
+ break;
+ }
+ }
+ if ( i == width) {
+ wrapHeight = qtrue;
+ }
+
+
+ for ( i = 0 ; i < width ; i++ ) {
+ for ( j = 0 ; j < height ; j++ ) {
+ count = 0;
+ dv = &ctrl[j][i];
+ VectorCopy( dv->xyz, base );
+ for ( k = 0 ; k < 8 ; k++ ) {
+ VectorClear( around[k] );
+ good[k] = qfalse;
+
+ for ( dist = 1 ; dist <= 3 ; dist++ ) {
+ x = i + neighbors[k][0] * dist;
+ y = j + neighbors[k][1] * dist;
+ if ( wrapWidth ) {
+ if ( x < 0 ) {
+ x = width - 1 + x;
+ } else if ( x >= width ) {
+ x = 1 + x - width;
+ }
+ }
+ if ( wrapHeight ) {
+ if ( y < 0 ) {
+ y = height - 1 + y;
+ } else if ( y >= height ) {
+ y = 1 + y - height;
+ }
+ }
+
+ if ( x < 0 || x >= width || y < 0 || y >= height ) {
+ break; // edge of patch
+ }
+ VectorSubtract( ctrl[y][x].xyz, base, temp );
+ if ( VectorNormalize2( temp, temp ) == 0 ) {
+ continue; // degenerate edge, get more dist
+ } else {
+ good[k] = qtrue;
+ VectorCopy( temp, around[k] );
+ break; // good edge
+ }
+ }
+ }
+
+ VectorClear( sum );
+ for ( k = 0 ; k < 8 ; k++ ) {
+ if ( !good[k] || !good[(k+1)&7] ) {
+ continue; // didn't get two points
+ }
+ CrossProduct( around[(k+1)&7], around[k], normal );
+ if ( VectorNormalize2( normal, normal ) == 0 ) {
+ continue;
+ }
+ VectorAdd( normal, sum, sum );
+ count++;
+ }
+ if ( count == 0 ) {
+//printf("bad normal\n");
+ count = 1;
+ }
+ VectorNormalize2( sum, dv->normal );
+ }
+ }
+}
+
+
+/*
+============
+InvertCtrl
+============
+*/
+static void InvertCtrl( int width, int height, drawVert_t ctrl[MAX_GRID_SIZE][MAX_GRID_SIZE] ) {
+ int i, j;
+ drawVert_t temp;
+
+ for ( i = 0 ; i < height ; i++ ) {
+ for ( j = 0 ; j < width/2 ; j++ ) {
+ temp = ctrl[i][j];
+ ctrl[i][j] = ctrl[i][width-1-j];
+ ctrl[i][width-1-j] = temp;
+ }
+ }
+}
+
+
+/*
+=================
+InvertErrorTable
+=================
+*/
+static void InvertErrorTable( float errorTable[2][MAX_GRID_SIZE], int width, int height ) {
+ int i;
+ float copy[2][MAX_GRID_SIZE];
+
+ Com_Memcpy( copy, errorTable, sizeof( copy ) );
+
+ for ( i = 0 ; i < width ; i++ ) {
+ errorTable[1][i] = copy[0][i]; //[width-1-i];
+ }
+
+ for ( i = 0 ; i < height ; i++ ) {
+ errorTable[0][i] = copy[1][height-1-i];
+ }
+
+}
+
+/*
+==================
+PutPointsOnCurve
+==================
+*/
+static void PutPointsOnCurve( drawVert_t ctrl[MAX_GRID_SIZE][MAX_GRID_SIZE],
+ int width, int height ) {
+ int i, j;
+ drawVert_t prev, next;
+
+ for ( i = 0 ; i < width ; i++ ) {
+ for ( j = 1 ; j < height ; j += 2 ) {
+ LerpDrawVert( &ctrl[j][i], &ctrl[j+1][i], &prev );
+ LerpDrawVert( &ctrl[j][i], &ctrl[j-1][i], &next );
+ LerpDrawVert( &prev, &next, &ctrl[j][i] );
+ }
+ }
+
+
+ for ( j = 0 ; j < height ; j++ ) {
+ for ( i = 1 ; i < width ; i += 2 ) {
+ LerpDrawVert( &ctrl[j][i], &ctrl[j][i+1], &prev );
+ LerpDrawVert( &ctrl[j][i], &ctrl[j][i-1], &next );
+ LerpDrawVert( &prev, &next, &ctrl[j][i] );
+ }
+ }
+}
+
+/*
+=================
+R_CreateSurfaceGridMesh
+=================
+*/
+srfGridMesh_t *R_CreateSurfaceGridMesh(int width, int height,
+ drawVert_t ctrl[MAX_GRID_SIZE][MAX_GRID_SIZE], float errorTable[2][MAX_GRID_SIZE] ) {
+ int i, j, size;
+ drawVert_t *vert;
+ vec3_t tmpVec;
+ srfGridMesh_t *grid;
+
+ // copy the results out to a grid
+ size = (width * height - 1) * sizeof( drawVert_t ) + sizeof( *grid );
+
+#ifdef PATCH_STITCHING
+ grid = /*ri.Hunk_Alloc*/ ri.Malloc( size );
+ Com_Memset(grid, 0, size);
+
+ grid->widthLodError = /*ri.Hunk_Alloc*/ ri.Malloc( width * 4 );
+ Com_Memcpy( grid->widthLodError, errorTable[0], width * 4 );
+
+ grid->heightLodError = /*ri.Hunk_Alloc*/ ri.Malloc( height * 4 );
+ Com_Memcpy( grid->heightLodError, errorTable[1], height * 4 );
+#else
+ grid = ri.Hunk_Alloc( size );
+ Com_Memset(grid, 0, size);
+
+ grid->widthLodError = ri.Hunk_Alloc( width * 4 );
+ Com_Memcpy( grid->widthLodError, errorTable[0], width * 4 );
+
+ grid->heightLodError = ri.Hunk_Alloc( height * 4 );
+ Com_Memcpy( grid->heightLodError, errorTable[1], height * 4 );
+#endif
+
+ grid->width = width;
+ grid->height = height;
+ grid->surfaceType = SF_GRID;
+ ClearBounds( grid->meshBounds[0], grid->meshBounds[1] );
+ for ( i = 0 ; i < width ; i++ ) {
+ for ( j = 0 ; j < height ; j++ ) {
+ vert = &grid->verts[j*width+i];
+ *vert = ctrl[j][i];
+ AddPointToBounds( vert->xyz, grid->meshBounds[0], grid->meshBounds[1] );
+ }
+ }
+
+ // compute local origin and bounds
+ VectorAdd( grid->meshBounds[0], grid->meshBounds[1], grid->localOrigin );
+ VectorScale( grid->localOrigin, 0.5f, grid->localOrigin );
+ VectorSubtract( grid->meshBounds[0], grid->localOrigin, tmpVec );
+ grid->meshRadius = VectorLength( tmpVec );
+
+ VectorCopy( grid->localOrigin, grid->lodOrigin );
+ grid->lodRadius = grid->meshRadius;
+ //
+ return grid;
+}
+
+/*
+=================
+R_FreeSurfaceGridMesh
+=================
+*/
+void R_FreeSurfaceGridMesh( srfGridMesh_t *grid ) {
+ ri.Free(grid->widthLodError);
+ ri.Free(grid->heightLodError);
+ ri.Free(grid);
+}
+
+/*
+=================
+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_cleared( prev );
+ drawVert_t_cleared( next );
+ drawVert_t_cleared( mid );
+ float len, maxLen;
+ int dir;
+ int t;
+ 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 midxyz2;
+ 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, midxyz2);
+ len = VectorLengthSquared( 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 );
+}
+
+/*
+===============
+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;
+ drawVert_t ctrl[MAX_GRID_SIZE][MAX_GRID_SIZE];
+ float errorTable[2][MAX_GRID_SIZE];
+ float lodRadius;
+ vec3_t lodOrigin;
+
+ 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 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_t point, float loderror ) {
+ int i, j;
+ int width, height, oldheight;
+ 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;
+}
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