doom3-bfg/neo/cm/CollisionModel_trace.cpp
2012-11-26 12:58:24 -06:00

257 lines
7.6 KiB
C++

/*
===========================================================================
Doom 3 BFG Edition GPL Source Code
Copyright (C) 1993-2012 id Software LLC, a ZeniMax Media company.
This file is part of the Doom 3 BFG Edition GPL Source Code ("Doom 3 BFG Edition Source Code").
Doom 3 BFG Edition 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 3 of the License, or
(at your option) any later version.
Doom 3 BFG Edition 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 Doom 3 BFG Edition Source Code. If not, see <http://www.gnu.org/licenses/>.
In addition, the Doom 3 BFG Edition Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the Doom 3 BFG Edition Source Code. If not, please request a copy in writing from id Software at the address below.
If you have questions concerning this license or the applicable additional terms, you may contact in writing id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.
===========================================================================
*/
/*
===============================================================================
Trace model vs. polygonal model collision detection.
===============================================================================
*/
#pragma hdrstop
#include "../idlib/precompiled.h"
#include "CollisionModel_local.h"
/*
===============================================================================
Trace through the spatial subdivision
===============================================================================
*/
/*
================
idCollisionModelManagerLocal::TraceTrmThroughNode
================
*/
void idCollisionModelManagerLocal::TraceTrmThroughNode( cm_traceWork_t *tw, cm_node_t *node ) {
cm_polygonRef_t *pref;
cm_brushRef_t *bref;
// position test
if ( tw->positionTest ) {
// if already stuck in solid
if ( tw->trace.fraction == 0.0f ) {
return;
}
// test if any of the trm vertices is inside a brush
for ( bref = node->brushes; bref; bref = bref->next ) {
if ( idCollisionModelManagerLocal::TestTrmVertsInBrush( tw, bref->b ) ) {
return;
}
}
// if just testing a point we're done
if ( tw->pointTrace ) {
return;
}
// test if the trm is stuck in any polygons
for ( pref = node->polygons; pref; pref = pref->next ) {
if ( idCollisionModelManagerLocal::TestTrmInPolygon( tw, pref->p ) ) {
return;
}
}
}
else if ( tw->rotation ) {
// rotate through all polygons in this leaf
for ( pref = node->polygons; pref; pref = pref->next ) {
if ( idCollisionModelManagerLocal::RotateTrmThroughPolygon( tw, pref->p ) ) {
return;
}
}
}
else {
// trace through all polygons in this leaf
for ( pref = node->polygons; pref; pref = pref->next ) {
if ( idCollisionModelManagerLocal::TranslateTrmThroughPolygon( tw, pref->p ) ) {
return;
}
}
}
}
/*
================
idCollisionModelManagerLocal::TraceThroughAxialBSPTree_r
================
*/
//#define NO_SPATIAL_SUBDIVISION
void idCollisionModelManagerLocal::TraceThroughAxialBSPTree_r( cm_traceWork_t *tw, cm_node_t *node, float p1f, float p2f, idVec3 &p1, idVec3 &p2) {
float t1, t2, offset;
float frac, frac2;
float idist;
idVec3 mid;
int side;
float midf;
if ( !node ) {
return;
}
if ( tw->quickExit ) {
return; // stop immediately
}
if ( tw->trace.fraction <= p1f ) {
return; // already hit something nearer
}
// if we need to test this node for collisions
if ( node->polygons || (tw->positionTest && node->brushes) ) {
// trace through node with collision data
idCollisionModelManagerLocal::TraceTrmThroughNode( tw, node );
}
// if already stuck in solid
if ( tw->positionTest && tw->trace.fraction == 0.0f ) {
return;
}
// if this is a leaf node
if ( node->planeType == -1 ) {
return;
}
#ifdef NO_SPATIAL_SUBDIVISION
idCollisionModelManagerLocal::TraceThroughAxialBSPTree_r( tw, node->children[0], p1f, p2f, p1, p2 );
idCollisionModelManagerLocal::TraceThroughAxialBSPTree_r( tw, node->children[1], p1f, p2f, p1, p2 );
return;
#endif
// distance from plane for trace start and end
t1 = p1[node->planeType] - node->planeDist;
t2 = p2[node->planeType] - node->planeDist;
// adjust the plane distance appropriately for mins/maxs
offset = tw->extents[node->planeType];
// see which sides we need to consider
if ( t1 >= offset && t2 >= offset ) {
idCollisionModelManagerLocal::TraceThroughAxialBSPTree_r( tw, node->children[0], p1f, p2f, p1, p2 );
return;
}
if ( t1 < -offset && t2 < -offset ) {
idCollisionModelManagerLocal::TraceThroughAxialBSPTree_r( tw, node->children[1], p1f, p2f, p1, p2 );
return;
}
if ( t1 < t2 ) {
idist = 1.0f / (t1-t2);
side = 1;
frac2 = (t1 + offset) * idist;
frac = (t1 - offset) * idist;
} else if (t1 > t2) {
idist = 1.0f / (t1-t2);
side = 0;
frac2 = (t1 - offset) * idist;
frac = (t1 + offset) * idist;
} else {
side = 0;
frac = 1.0f;
frac2 = 0.0f;
}
// move up to the node
if ( frac < 0.0f ) {
frac = 0.0f;
}
else if ( frac > 1.0f ) {
frac = 1.0f;
}
midf = p1f + (p2f - p1f)*frac;
mid[0] = p1[0] + frac*(p2[0] - p1[0]);
mid[1] = p1[1] + frac*(p2[1] - p1[1]);
mid[2] = p1[2] + frac*(p2[2] - p1[2]);
idCollisionModelManagerLocal::TraceThroughAxialBSPTree_r( tw, node->children[side], p1f, midf, p1, mid );
// go past the node
if ( frac2 < 0.0f ) {
frac2 = 0.0f;
}
else if ( frac2 > 1.0f ) {
frac2 = 1.0f;
}
midf = p1f + (p2f - p1f)*frac2;
mid[0] = p1[0] + frac2*(p2[0] - p1[0]);
mid[1] = p1[1] + frac2*(p2[1] - p1[1]);
mid[2] = p1[2] + frac2*(p2[2] - p1[2]);
idCollisionModelManagerLocal::TraceThroughAxialBSPTree_r( tw, node->children[side^1], midf, p2f, mid, p2 );
}
/*
================
idCollisionModelManagerLocal::TraceThroughModel
================
*/
void idCollisionModelManagerLocal::TraceThroughModel( cm_traceWork_t *tw ) {
float d;
int i, numSteps;
idVec3 start, end;
idRotation rot;
if ( !tw->rotation ) {
// trace through spatial subdivision and then through leafs
idCollisionModelManagerLocal::TraceThroughAxialBSPTree_r( tw, tw->model->node, 0, 1, tw->start, tw->end );
}
else {
// approximate the rotation with a series of straight line movements
// total length covered along circle
d = tw->radius * DEG2RAD( tw->angle );
// if more than one step
if ( d > CIRCLE_APPROXIMATION_LENGTH ) {
// number of steps for the approximation
numSteps = (int) (CIRCLE_APPROXIMATION_LENGTH / d);
// start of approximation
start = tw->start;
// trace circle approximation steps through the BSP tree
for ( i = 0; i < numSteps; i++ ) {
// calculate next point on approximated circle
rot.Set( tw->origin, tw->axis, tw->angle * ((float) (i+1) / numSteps) );
end = start * rot;
// trace through spatial subdivision and then through leafs
idCollisionModelManagerLocal::TraceThroughAxialBSPTree_r( tw, tw->model->node, 0, 1, start, end );
// no need to continue if something was hit already
if ( tw->trace.fraction < 1.0f ) {
return;
}
start = end;
}
}
else {
start = tw->start;
}
// last step of the approximation
idCollisionModelManagerLocal::TraceThroughAxialBSPTree_r( tw, tw->model->node, 0, 1, start, tw->end );
}
}