ref: bf5dc91f8d7bc2035effd18290c523050fa1b2cd
dir: /code/qcommon/cm_patch.h/
/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.
This file is part of Quake III Arena source code.
Quake III Arena source code 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.
Quake III Arena source code 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 Foobar; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
===========================================================================
*/
//#define CULL_BBOX
/*
This file does not reference any globals, and has these entry points:
void CM_ClearLevelPatches( void );
struct patchCollide_s *CM_GeneratePatchCollide( int width, int height, const vec3_t *points );
void CM_TraceThroughPatchCollide( traceWork_t *tw, const struct patchCollide_s *pc );
qboolean CM_PositionTestInPatchCollide( traceWork_t *tw, const struct patchCollide_s *pc );
void CM_DrawDebugSurface( void (*drawPoly)(int color, int numPoints, flaot *points) );
Issues for collision against curved surfaces:
Surface edges need to be handled differently than surface planes
Plane expansion causes raw surfaces to expand past expanded bounding box
Position test of a volume against a surface is tricky.
Position test of a point against a surface is not well defined, because the surface has no volume.
Tracing leading edge points instead of volumes?
Position test by tracing corner to corner? (8*7 traces -- ouch)
coplanar edges
triangulated patches
degenerate patches
endcaps
degenerate
WARNING: this may misbehave with meshes that have rows or columns that only
degenerate a few triangles. Completely degenerate rows and columns are handled
properly.
*/
#define MAX_FACETS 1024
#define MAX_PATCH_PLANES 2048
typedef struct {
float plane[4];
int signbits; // signx + (signy<<1) + (signz<<2), used as lookup during collision
} patchPlane_t;
typedef struct {
int surfacePlane;
int numBorders; // 3 or four + 6 axial bevels + 4 or 3 * 4 edge bevels
int borderPlanes[4+6+16];
int borderInward[4+6+16];
qboolean borderNoAdjust[4+6+16];
} facet_t;
typedef struct patchCollide_s {
vec3_t bounds[2];
int numPlanes; // surface planes plus edge planes
patchPlane_t *planes;
int numFacets;
facet_t *facets;
} patchCollide_t;
#define MAX_GRID_SIZE 129
typedef struct {
int width;
int height;
qboolean wrapWidth;
qboolean wrapHeight;
vec3_t points[MAX_GRID_SIZE][MAX_GRID_SIZE]; // [width][height]
} cGrid_t;
#define SUBDIVIDE_DISTANCE 16 //4 // never more than this units away from curve
#define PLANE_TRI_EPSILON 0.1
#define WRAP_POINT_EPSILON 0.1
struct patchCollide_s *CM_GeneratePatchCollide( int width, int height, vec3_t *points );