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Xash3DArchive/cms_xr/cm_patch.c

1043 lines
26 KiB
C

//=======================================================================
// Copyright XashXT Group 2009 ©
// cm_patch.c - curves collision
//=======================================================================
#include "cm_local.h"
#include "mathlib.h"
int c_totalPatchBlocks;
vec3_t debugBlockPoints[4];
const cSurfaceCollide_t *debugSurfaceCollide;
const cfacet_t *debugFacet;
bool debugBlock;
/*
=================
CM_ClearLevelPatches
=================
*/
void CM_ClearLevelPatches( void )
{
debugSurfaceCollide = NULL;
debugFacet = NULL;
}
/*
================================================================================
GRID SUBDIVISION
================================================================================
*/
/*
=================
CM_NeedsSubdivision
Returns true if the given quadratic curve is not flat enough for our
collision detection purposes
=================
*/
static bool CM_NeedsSubdivision( vec3_t a, vec3_t b, vec3_t c )
{
vec3_t cmid, lmid;
vec3_t delta;
float dist;
int i;
// calculate the linear midpoint
for( i = 0; i < 3; i++ )
lmid[i] = 0.5 * (a[i] + c[i]);
// calculate the exact curve midpoint
for( i = 0; i < 3; i++ )
cmid[i] = 0.5f * (0.5f * (a[i] + b[i]) + 0.5f * (b[i] + c[i]));
// see if the curve is far enough away from the linear mid
VectorSubtract( cmid, lmid, delta );
dist = VectorLength( delta );
return dist >= SUBDIVIDE_DISTANCE;
}
/*
===============
CM_Subdivide
a, b, and c are control points.
the subdivided sequence will be: a, out1, out2, out3, c
===============
*/
static void CM_Subdivide( vec3_t a, vec3_t b, vec3_t c, vec3_t out1, vec3_t out2, vec3_t out3 )
{
int i;
for( i = 0; i < 3; i++ )
{
out1[i] = 0.5f * (a[i] + b[i]);
out3[i] = 0.5f * (b[i] + c[i]);
out2[i] = 0.5f * (out1[i] + out3[i]);
}
}
/*
=================
CM_TransposeGrid
Swaps the rows and columns in place
=================
*/
static void CM_TransposeGrid( cgrid_t *grid )
{
int i, j, l;
vec3_t temp;
bool tempWrap;
if( grid->width > grid->height )
{
for( i = 0; i < grid->height; i++ )
{
for( j = i + 1; j < grid->width; j++ )
{
if( j < grid->height )
{
// swap the value
VectorCopy( grid->points[i][j], temp );
VectorCopy( grid->points[j][i], grid->points[i][j] );
VectorCopy( temp, grid->points[j][i] );
}
else
{
// just copy
VectorCopy( grid->points[j][i], grid->points[i][j] );
}
}
}
}
else
{
for( i = 0; i < grid->width; i++ )
{
for( j = i + 1; j < grid->height; j++ )
{
if( j < grid->width )
{
// swap the value
VectorCopy( grid->points[j][i], temp );
VectorCopy( grid->points[i][j], grid->points[j][i] );
VectorCopy( temp, grid->points[i][j] );
}
else
{
// just copy
VectorCopy( grid->points[i][j], grid->points[j][i] );
}
}
}
}
l = grid->width;
grid->width = grid->height;
grid->height = l;
tempWrap = grid->wrapWidth;
grid->wrapWidth = grid->wrapHeight;
grid->wrapHeight = tempWrap;
}
/*
===================
CM_SetGridWrapWidth
If the left and right columns are exactly equal, set grid->wrapWidth true
===================
*/
static void CM_SetGridWrapWidth( cgrid_t *grid )
{
int i, j;
float d;
for( i = 0; i < grid->height; i++ )
{
for( j = 0; j < 3; j++ )
{
d = grid->points[0][i][j] - grid->points[grid->width - 1][i][j];
if( d < -WRAP_POINT_EPSILON || d > WRAP_POINT_EPSILON )
break;
}
if( j != 3 ) break;
}
if( i == grid->height )
grid->wrapWidth = true;
else grid->wrapWidth = false;
}
/*
=================
CM_SubdivideGridColumns
Adds columns as necessary to the grid until
all the aproximating points are within SUBDIVIDE_DISTANCE
from the true curve
=================
*/
static void CM_SubdivideGridColumns( cgrid_t *grid )
{
int i, j, k;
for( i = 0; i < grid->width - 2; )
{
// grid->points[i][x] is an interpolating control point
// grid->points[i+1][x] is an aproximating control point
// grid->points[i+2][x] is an interpolating control point
// first see if we can collapse the aproximating collumn away
for( j = 0; j < grid->height; j++ )
{
if( CM_NeedsSubdivision( grid->points[i][j], grid->points[i + 1][j], grid->points[i + 2][j] ))
break;
}
if( j == grid->height )
{
// all of the points were close enough to the linear midpoints
// that we can collapse the entire column away
for( j = 0; j < grid->height; j++ )
{
// remove the column
for( k = i + 2; k < grid->width; k++ )
VectorCopy( grid->points[k][j], grid->points[k - 1][j] );
}
grid->width--;
// go to the next curve segment
i++;
continue;
}
// we need to subdivide the curve
for( j = 0; j < grid->height; j++ )
{
vec3_t prev, mid, next;
// save the control points now
VectorCopy( grid->points[i][j], prev );
VectorCopy( grid->points[i + 1][j], mid );
VectorCopy( grid->points[i + 2][j], next );
// make room for two additional columns in the grid
// columns i+1 will be replaced, column i+2 will become i+4
// i+1, i+2, and i+3 will be generated
for( k = grid->width - 1; k > i + 1; k-- )
VectorCopy( grid->points[k][j], grid->points[k + 2][j] );
// generate the subdivided points
CM_Subdivide( prev, mid, next, grid->points[i+1][j], grid->points[i+2][j], grid->points[i+3][j] );
}
grid->width += 2;
// the new aproximating point at i+1 may need to be removed
// or subdivided farther, so don't advance i
}
}
/*
======================
CM_ComparePoints
======================
*/
static bool CM_ComparePoints( float *a, float *b )
{
float d;
d = a[0] - b[0];
if( d < -ON_EPSILON || d > ON_EPSILON )
return false;
d = a[1] - b[1];
if( d < -ON_EPSILON || d > ON_EPSILON )
return false;
d = a[2] - b[2];
if( d < -ON_EPSILON || d > ON_EPSILON )
return false;
return true;
}
/*
=================
CM_RemoveDegenerateColumns
If there are any identical columns, remove them
=================
*/
static void CM_RemoveDegenerateColumns( cgrid_t *grid )
{
int i, j, k;
for( i = 0; i < grid->width - 1; i++ )
{
for( j = 0; j < grid->height; j++ )
{
if(!CM_ComparePoints( grid->points[i][j], grid->points[i + 1][j] ))
break;
}
if( j != grid->height )
continue; // not degenerate
for( j = 0; j < grid->height; j++ )
{
// remove the column
for( k = i + 2; k < grid->width; k++ )
VectorCopy( grid->points[k][j], grid->points[k-1][j] );
}
grid->width--;
// check against the next column
i--;
}
}
/*
================================================================================
PATCH COLLIDE GENERATION
================================================================================
*/
static int numPlanes;
static cmplane_t planes[MAX_PATCH_PLANES];
static int numFacets;
static cfacet_t facets[MAX_PATCH_PLANES]; // maybe MAX_FACETS ??
/*
==================
CM_FindPlane2
==================
*/
static int CM_FindPlane2( float plane[4], int *flipped )
{
int i;
// see if the points are close enough to an existing plane
for( i = 0; i < numPlanes; i++ )
{
if( CM_PlaneEqual( &planes[i], plane, flipped ))
return i;
}
// add a new plane
if( numPlanes == MAX_PATCH_PLANES )
Host_Error( "CM_FindPlane2: MAX_PATCH_PLANES limit exceeded\n" );
Vector4Copy( plane, planes[numPlanes].plane );
planes[numPlanes].signbits = SignbitsForPlane( plane );
numPlanes++;
*flipped = false;
return numPlanes - 1;
}
/*
==================
CM_FindPlane
==================
*/
static int CM_FindPlane( float *p1, float *p2, float *p3 )
{
float d, plane[4];
int i;
if( !CM_PlaneFromPoints( plane, p1, p2, p3 ))
return -1;
// see if the points are close enough to an existing plane
for( i = 0; i < numPlanes; i++ )
{
if( DotProduct( plane, planes[i].plane ) < 0.0f )
continue; // allow backwards planes?
d = DotProduct( p1, planes[i].plane ) - planes[i].plane[3];
if( d < -PLANE_TRI_EPSILON || d > PLANE_TRI_EPSILON )
continue;
d = DotProduct( p2, planes[i].plane) - planes[i].plane[3];
if( d < -PLANE_TRI_EPSILON || d > PLANE_TRI_EPSILON )
continue;
d = DotProduct( p3, planes[i].plane) - planes[i].plane[3];
if( d < -PLANE_TRI_EPSILON || d > PLANE_TRI_EPSILON )
continue;
// found it
return i;
}
// add a new plane
if( numPlanes == MAX_PATCH_PLANES )
Host_Error( "MAX_PATCH_PLANES limit exceeded\n" );
Vector4Copy(plane, planes[numPlanes].plane);
planes[numPlanes].signbits = SignbitsForPlane(plane);
numPlanes++;
return numPlanes - 1;
}
/*
==================
CM_PointOnPlaneSide
==================
*/
static int CM_PointOnPlaneSide( float *p, int planeNum )
{
float d, *plane;
if( planeNum == -1 )
return SIDE_ON;
plane = planes[planeNum].plane;
d = DotProduct( p, plane ) - plane[3];
if( d > PLANE_TRI_EPSILON )
return SIDE_FRONT;
if( d < -PLANE_TRI_EPSILON )
return SIDE_BACK;
return SIDE_ON;
}
/*
==================
CM_GridPlane
==================
*/
static int CM_GridPlane( int gridPlanes[MAX_GRID_SIZE][MAX_GRID_SIZE][2], int i, int j, int tri )
{
int p;
p = gridPlanes[i][j][tri];
if( p != -1 )
return p;
p = gridPlanes[i][j][!tri];
if( p != -1 )
return p;
// should never happen
MsgDev( D_WARN, "CM_GridPlane: unresolvable\n" );
return -1;
}
/*
==================
CM_EdgePlaneNum
==================
*/
static int CM_EdgePlaneNum( cgrid_t *grid, int gridPlanes[MAX_GRID_SIZE][MAX_GRID_SIZE][2], int i, int j, int k )
{
float *p1, *p2;
vec3_t up;
int p;
switch( k )
{
case 0: // top border
p1 = grid->points[i][j];
p2 = grid->points[i+1][j];
p = CM_GridPlane(gridPlanes, i, j, 0 );
VectorMA( p1, 4, planes[p].plane, up );
return CM_FindPlane( p1, p2, up );
case 2: // bottom border
p1 = grid->points[i][j+1];
p2 = grid->points[i+1][j+1];
p = CM_GridPlane( gridPlanes, i, j, 1 );
VectorMA( p1, 4, planes[p].plane, up );
return CM_FindPlane( p2, p1, up );
case 3: // left border
p1 = grid->points[i][j];
p2 = grid->points[i][j+1];
p = CM_GridPlane( gridPlanes, i, j, 1 );
VectorMA( p1, 4, planes[p].plane, up );
return CM_FindPlane( p2, p1, up );
case 1: // right border
p1 = grid->points[i+1][j];
p2 = grid->points[i+1][j+1];
p = CM_GridPlane( gridPlanes, i, j, 0 );
VectorMA( p1, 4, planes[p].plane, up );
return CM_FindPlane( p1, p2, up );
case 4: // diagonal out of triangle 0
p1 = grid->points[i+1][j+1];
p2 = grid->points[i][j];
p = CM_GridPlane( gridPlanes, i, j, 0 );
VectorMA( p1, 4, planes[p].plane, up );
return CM_FindPlane( p1, p2, up );
case 5: // diagonal out of triangle 1
p1 = grid->points[i][j];
p2 = grid->points[i+1][j+1];
p = CM_GridPlane( gridPlanes, i, j, 1 );
VectorMA( p1, 4, planes[p].plane, up );
return CM_FindPlane( p1, p2, up );
}
Host_Error( "CM_EdgePlaneNum: bad planenum %i\n", k );
return -1;
}
/*
===================
CM_SetBorderInward
===================
*/
static void CM_SetBorderInward( cfacet_t *facet, cgrid_t *grid, int gridPlanes[MAX_GRID_SIZE][MAX_GRID_SIZE][2], int i, int j, int which )
{
int k, l;
float *points[4];
int numPoints;
switch( which )
{
case -1:
points[0] = grid->points[i][j];
points[1] = grid->points[i+1][j];
points[2] = grid->points[i+1][j+1];
points[3] = grid->points[i][j+1];
numPoints = 4;
break;
case 0:
points[0] = grid->points[i][j];
points[1] = grid->points[i+1][j];
points[2] = grid->points[i+1][j+1];
numPoints = 3;
break;
case 1:
points[0] = grid->points[i+1][j+1];
points[1] = grid->points[i][j+1];
points[2] = grid->points[i][j];
numPoints = 3;
break;
default:
Host_Error( "CM_SetBorderInward: bad parameter %i\n", which );
numPoints = 0;
break;
}
for( k = 0; k < facet->numBorders; k++ )
{
int front, back;
front = 0;
back = 0;
for( l = 0; l < numPoints; l++ )
{
int side;
side = CM_PointOnPlaneSide( points[l], facet->borderPlanes[k] );
if( side == SIDE_FRONT ) front++;
if( side == SIDE_BACK ) back++;
}
if( front && !back )
facet->borderInward[k] = true;
else if( back && !front )
facet->borderInward[k] = false;
else if( !front && !back )
facet->borderPlanes[k] = -1; // flat side border
else
{
// bisecting side border
MsgDev( D_WARN, "CM_SetBorderInward: mixed plane sides\n" );
facet->borderInward[k] = false;
if( !debugBlock )
{
debugBlock = true;
VectorCopy( grid->points[i][j], debugBlockPoints[0] );
VectorCopy( grid->points[i+1][j], debugBlockPoints[1] );
VectorCopy( grid->points[i+1][j+1], debugBlockPoints[2] );
VectorCopy( grid->points[i][j+1], debugBlockPoints[3] );
}
}
}
}
/*
==================
CM_ValidateFacet
If the facet isn't bounded by its borders, we screwed up.
==================
*/
static bool CM_ValidateFacet( cfacet_t *facet )
{
int j;
cwinding_t *w;
float plane[4];
vec3_t bounds[2];
if( facet->surfacePlane == -1 )
return false;
Vector4Copy( planes[facet->surfacePlane].plane, plane );
w = CM_BaseWindingForPlane( plane, plane[3] );
for( j = 0; j < facet->numBorders && w; j++ )
{
if( facet->borderPlanes[j] == -1 )
{
CM_FreeWinding( w );
return false;
}
Vector4Copy( planes[facet->borderPlanes[j]].plane, plane );
if( !facet->borderInward[j] )
{
VectorSubtract( vec3_origin, plane, plane );
plane[3] = -plane[3];
}
CM_ChopWindingInPlace( &w, plane, plane[3], ON_EPSILON );
}
if( !w ) return false; // winding was completely chopped away
// see if the facet is unreasonably large
CM_WindingBounds( w, bounds[0], bounds[1] );
CM_FreeWinding( w );
for( j = 0; j < 3; j++ )
{
if( bounds[1][j] - bounds[0][j] > MAX_WORLD_COORD )
return false; // we must be missing a plane
if( bounds[0][j] >= MAX_WORLD_COORD )
return false;
if( bounds[1][j] <= MIN_WORLD_COORD )
return false;
}
return true; // winding is fine
}
/*
==================
CM_AddFacetBevels
==================
*/
static void CM_AddFacetBevels( cfacet_t *facet )
{
int i, j, k, l;
int axis, dir, order, flipped;
float plane[4], d, newplane[4];
vec3_t mins, maxs, vec, vec2;
cwinding_t *w, *w2;
Vector4Copy( planes[facet->surfacePlane].plane, plane );
w = CM_BaseWindingForPlane( plane, plane[3] );
for( j = 0; j < facet->numBorders && w; j++ )
{
if( facet->borderPlanes[j] == facet->surfacePlane )
continue;
Vector4Copy( planes[facet->borderPlanes[j]].plane, plane );
if( !facet->borderInward[j] )
{
VectorSubtract( vec3_origin, plane, plane );
plane[3] = -plane[3];
}
CM_ChopWindingInPlace( &w, plane, plane[3], ON_EPSILON );
}
if( !w ) return;
CM_WindingBounds( w, mins, maxs );
// add the axial planes
order = 0;
for( axis = 0; axis < 3; axis++ )
{
for( dir = -1; dir <= 1; dir += 2, order++ )
{
VectorClear( plane );
plane[axis] = dir;
if( dir == 1 ) plane[3] = maxs[axis];
else plane[3] = -mins[axis];
// if it's the surface plane
if( CM_PlaneEqual( &planes[facet->surfacePlane], plane, &flipped ))
continue;
// see if the plane is allready present
for( i = 0; i < facet->numBorders; i++ )
{
if( CM_PlaneEqual( &planes[facet->borderPlanes[i]], plane, &flipped ))
break;
}
if( i == facet->numBorders )
{
if( facet->numBorders > MAX_FACET_BEVELS )
MsgDev( D_ERROR, "CM_AddFacetBevels: too many bevels\n" );
facet->borderPlanes[facet->numBorders] = CM_FindPlane2( plane, &flipped );
facet->borderNoAdjust[facet->numBorders] = 0;
facet->borderInward[facet->numBorders] = flipped;
facet->numBorders++;
}
}
}
// add the edge bevels
// test the non-axial plane edges
for( j = 0; j < w->numpoints; j++ )
{
k = (j + 1) % w->numpoints;
VectorSubtract( w->p[j], w->p[k], vec );
// if it's a degenerate edge
if( VectorNormalizeLength( vec ) < 0.5f )
continue;
CM_SnapVector( vec );
for( k = 0; k < 3; k++ )
{
if( vec[k] == -1 || vec[k] == 1 )
break; // axial
}
if( k < 3 ) continue; // only test non-axial edges
// try the six possible slanted axials from this edge
for( axis = 0; axis < 3; axis++ )
{
for( dir = -1; dir <= 1; dir += 2 )
{
// construct a plane
VectorClear( vec2 );
vec2[axis] = dir;
CrossProduct( vec, vec2, plane );
if( VectorNormalizeLength( plane ) < 0.5f )
continue;
plane[3] = DotProduct( w->p[j], plane );
// if all the points of the facet winding are
// behind this plane, it is a proper edge bevel
for( l = 0; l < w->numpoints; l++ )
{
d = DotProduct( w->p[l], plane ) - plane[3];
if( d > ON_EPSILON ) break; // point in front
}
if( l < w->numpoints ) continue;
//if it's the surface plane
if( CM_PlaneEqual( &planes[facet->surfacePlane], plane, &flipped ))
continue;
// see if the plane is allready present
for( i = 0; i < facet->numBorders; i++ )
{
if( CM_PlaneEqual( &planes[facet->borderPlanes[i]], plane, &flipped ))
break;
}
if( i == facet->numBorders )
{
if( facet->numBorders > MAX_FACET_BEVELS )
MsgDev( D_ERROR, "CM_AddFacetBevels: too many bevels\n" );
facet->borderPlanes[facet->numBorders] = CM_FindPlane2( plane, &flipped );
for( k = 0; k < facet->numBorders; k++ )
{
if( facet->borderPlanes[facet->numBorders] == facet->borderPlanes[k] )
MsgDev( D_WARN, "CM_AddFacetBevels: bevel plane already used\n" );
}
facet->borderNoAdjust[facet->numBorders] = 0;
facet->borderInward[facet->numBorders] = flipped;
w2 = CM_CopyWinding( w );
Vector4Copy( planes[facet->borderPlanes[facet->numBorders]].plane, newplane );
if( !facet->borderInward[facet->numBorders] )
{
VectorNegate( newplane, newplane );
newplane[3] = -newplane[3];
}
CM_ChopWindingInPlace( &w2, newplane, newplane[3], ON_EPSILON );
if( !w2 )
{
cm.numInvalidBevels++;
continue;
}
else CM_FreeWinding( w2 );
facet->numBorders++;
// already got a bevel
}
}
}
}
CM_FreeWinding( w );
// add opposite plane
facet->borderPlanes[facet->numBorders] = facet->surfacePlane;
facet->borderNoAdjust[facet->numBorders] = 0;
facet->borderInward[facet->numBorders] = true;
facet->numBorders++;
}
typedef enum
{
EN_TOP,
EN_RIGHT,
EN_BOTTOM,
EN_LEFT
} edgeName_t;
/*
==================
CM_PatchCollideFromGrid
==================
*/
static void CM_SurfaceCollideFromGrid( cgrid_t *grid, cSurfaceCollide_t *sc )
{
int i, j;
float *p1, *p2, *p3;
int gridPlanes[MAX_GRID_SIZE][MAX_GRID_SIZE][2];
cfacet_t *facet;
int borders[4];
int noAdjust[4];
numPlanes = 0;
numFacets = 0;
// find the planes for each triangle of the grid
for( i = 0; i < grid->width - 1; i++ )
{
for( j = 0; j < grid->height - 1; j++ )
{
p1 = grid->points[i][j];
p2 = grid->points[i+1][j];
p3 = grid->points[i+1][j+1];
gridPlanes[i][j][0] = CM_FindPlane( p1, p2, p3 );
p1 = grid->points[i+1][j+1];
p2 = grid->points[i][j+1];
p3 = grid->points[i][j];
gridPlanes[i][j][1] = CM_FindPlane( p1, p2, p3 );
}
}
// create the borders for each facet
for( i = 0; i < grid->width - 1; i++ )
{
for( j = 0; j < grid->height - 1; j++ )
{
borders[EN_TOP] = -1;
if( j > 0 ) borders[EN_TOP] = gridPlanes[i][j-1][1];
else if( grid->wrapHeight ) borders[EN_TOP] = gridPlanes[i][grid->height-2][1];
noAdjust[EN_TOP] = (borders[EN_TOP] == gridPlanes[i][j][0]);
if( borders[EN_TOP] == -1 || noAdjust[EN_TOP] )
borders[EN_TOP] = CM_EdgePlaneNum( grid, gridPlanes, i, j, 0 );
borders[EN_BOTTOM] = -1;
if( j < grid->height - 2 ) borders[EN_BOTTOM] = gridPlanes[i][j+1][0];
else if( grid->wrapHeight ) borders[EN_BOTTOM] = gridPlanes[i][0][0];
noAdjust[EN_BOTTOM] = (borders[EN_BOTTOM] == gridPlanes[i][j][1]);
if( borders[EN_BOTTOM] == -1 || noAdjust[EN_BOTTOM] )
borders[EN_BOTTOM] = CM_EdgePlaneNum( grid, gridPlanes, i, j, 2 );
borders[EN_LEFT] = -1;
if( i > 0 ) borders[EN_LEFT] = gridPlanes[i - 1][j][0];
else if( grid->wrapWidth ) borders[EN_LEFT] = gridPlanes[grid->width-2][j][0];
noAdjust[EN_LEFT] = (borders[EN_LEFT] == gridPlanes[i][j][1]);
if( borders[EN_LEFT] == -1 || noAdjust[EN_LEFT] )
borders[EN_LEFT] = CM_EdgePlaneNum( grid, gridPlanes, i, j, 3 );
borders[EN_RIGHT] = -1;
if( i < grid->width - 2 ) borders[EN_RIGHT] = gridPlanes[i+1][j][1];
else if( grid->wrapWidth ) borders[EN_RIGHT] = gridPlanes[0][j][1];
noAdjust[EN_RIGHT] = (borders[EN_RIGHT] == gridPlanes[i][j][0]);
if( borders[EN_RIGHT] == -1 || noAdjust[EN_RIGHT] )
borders[EN_RIGHT] = CM_EdgePlaneNum( grid, gridPlanes, i, j, 1 );
if( numFacets == MAX_FACETS )
Host_Error( "MAX_FACETS limit exceeded\n" );
facet = &facets[numFacets];
Mem_Set( facet, 0, sizeof( *facet ));
if( gridPlanes[i][j][0] == gridPlanes[i][j][1] )
{
if( gridPlanes[i][j][0] == -1 )
continue; // degenrate
facet->surfacePlane = gridPlanes[i][j][0];
facet->numBorders = 4;
facet->borderPlanes[0] = borders[EN_TOP];
facet->borderNoAdjust[0] = noAdjust[EN_TOP];
facet->borderPlanes[1] = borders[EN_RIGHT];
facet->borderNoAdjust[1] = noAdjust[EN_RIGHT];
facet->borderPlanes[2] = borders[EN_BOTTOM];
facet->borderNoAdjust[2] = noAdjust[EN_BOTTOM];
facet->borderPlanes[3] = borders[EN_LEFT];
facet->borderNoAdjust[3] = noAdjust[EN_LEFT];
CM_SetBorderInward( facet, grid, gridPlanes, i, j, -1 );
if( CM_ValidateFacet( facet ))
{
CM_AddFacetBevels( facet );
numFacets++;
}
}
else
{
// two seperate triangles
facet->surfacePlane = gridPlanes[i][j][0];
facet->numBorders = 3;
facet->borderPlanes[0] = borders[EN_TOP];
facet->borderNoAdjust[0] = noAdjust[EN_TOP];
facet->borderPlanes[1] = borders[EN_RIGHT];
facet->borderNoAdjust[1] = noAdjust[EN_RIGHT];
facet->borderPlanes[2] = gridPlanes[i][j][1];
if( facet->borderPlanes[2] == -1 )
{
facet->borderPlanes[2] = borders[EN_BOTTOM];
if( facet->borderPlanes[2] == -1 )
facet->borderPlanes[2] = CM_EdgePlaneNum( grid, gridPlanes, i, j, 4 );
}
CM_SetBorderInward( facet, grid, gridPlanes, i, j, 0 );
if( CM_ValidateFacet( facet ))
{
CM_AddFacetBevels( facet );
numFacets++;
}
if( numFacets == MAX_FACETS )
Host_Error( "MAX_FACETS limit exceeded\n" );
facet = &facets[numFacets];
Mem_Set( facet, 0, sizeof( *facet ));
facet->surfacePlane = gridPlanes[i][j][1];
facet->numBorders = 3;
facet->borderPlanes[0] = borders[EN_BOTTOM];
facet->borderNoAdjust[0] = noAdjust[EN_BOTTOM];
facet->borderPlanes[1] = borders[EN_LEFT];
facet->borderNoAdjust[1] = noAdjust[EN_LEFT];
facet->borderPlanes[2] = gridPlanes[i][j][0];
if( facet->borderPlanes[2] == -1 )
{
facet->borderPlanes[2] = borders[EN_TOP];
if( facet->borderPlanes[2] == -1 )
facet->borderPlanes[2] = CM_EdgePlaneNum( grid, gridPlanes, i, j, 5 );
}
CM_SetBorderInward( facet, grid, gridPlanes, i, j, 1 );
if( CM_ValidateFacet( facet ))
{
CM_AddFacetBevels( facet );
numFacets++;
}
}
}
}
// copy the results out
sc->numPlanes = numPlanes;
sc->numFacets = numFacets;
sc->facets = Mem_Alloc( cms.mempool, numFacets * sizeof( *sc->facets ));
Mem_Copy( sc->facets, facets, numFacets * sizeof( *sc->facets ));
sc->planes = Mem_Alloc( cms.mempool, numPlanes * sizeof( *sc->planes ));
Mem_Copy( sc->planes, planes, numPlanes * sizeof( *sc->planes ));
}
/*
===================
CM_GeneratePatchCollide
Creates an internal structure that will be used to perform
collision detection with a patch mesh.
Points is packed as concatenated rows.
===================
*/
cSurfaceCollide_t *CM_GeneratePatchCollide( int width, int height, vec3_t *points )
{
cSurfaceCollide_t *sc;
static cgrid_t grid;
int i, j;
if( width <= 2 || height <= 2 || !points )
{
Host_Error( "CM_GeneratePatchCollide: bad params: (%i, %i)\n", width, height );
}
if( !( width & 1 ) || !( height & 1 ))
Host_Error( "CM_GeneratePatchCollide: even sizes are invalid for quadratic meshes\n" );
if( width > MAX_GRID_SIZE || height > MAX_GRID_SIZE )
Host_Error( "CM_GeneratePatchCollide: source is > MAX_GRID_SIZE\n" );
// build a grid
grid.width = width;
grid.height = height;
grid.wrapWidth = false;
grid.wrapHeight = false;
for( i = 0; i < width; i++ )
{
for( j = 0; j < height; j++ )
VectorCopy(points[j*width+i], grid.points[i][j]);
}
// subdivide the grid
CM_SetGridWrapWidth( &grid );
CM_SubdivideGridColumns( &grid );
CM_RemoveDegenerateColumns( &grid );
CM_TransposeGrid( &grid );
CM_SetGridWrapWidth( &grid );
CM_SubdivideGridColumns( &grid );
CM_RemoveDegenerateColumns( &grid );
// we now have a grid of points exactly on the curve
// the aproximate surface defined by these points will be
// collided against
sc = Mem_Alloc( cms.mempool, sizeof( *sc ));
ClearBounds( sc->bounds[0], sc->bounds[1] );
for( i = 0; i < grid.width; i++ )
{
for( j = 0; j < grid.height; j++ )
AddPointToBounds( grid.points[i][j], sc->bounds[0], sc->bounds[1] );
}
c_totalPatchBlocks += (grid.width - 1) * (grid.height - 1);
// generate a bsp tree for the surface
CM_SurfaceCollideFromGrid( &grid, sc );
// expand by one unit for epsilon purposes
sc->bounds[0][0] -= 1;
sc->bounds[0][1] -= 1;
sc->bounds[0][2] -= 1;
sc->bounds[1][0] += 1;
sc->bounds[1][1] += 1;
sc->bounds[1][2] += 1;
return sc;
}