dhewm3/neo/renderer/tr_trace.cpp
Timothee 'TTimo' Besset fb1609f554 hello world
2011-11-22 15:28:15 -06:00

427 lines
11 KiB
C++

/*
===========================================================================
Doom 3 GPL Source Code
Copyright (C) 1999-2011 id Software LLC, a ZeniMax Media company.
This file is part of the Doom 3 GPL Source Code (?Doom 3 Source Code?).
Doom 3 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 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 Source Code. If not, see <http://www.gnu.org/licenses/>.
In addition, the Doom 3 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 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.
===========================================================================
*/
#include "../idlib/precompiled.h"
#pragma hdrstop
#include "tr_local.h"
//#define TEST_TRACE
/*
=================
R_LocalTrace
If we resort the vertexes so all silverts come first, we can save some work here.
=================
*/
localTrace_t R_LocalTrace( const idVec3 &start, const idVec3 &end, const float radius, const srfTriangles_t *tri ) {
int i, j;
byte * cullBits;
idPlane planes[4];
localTrace_t hit;
int c_testEdges, c_testPlanes, c_intersect;
idVec3 startDir;
byte totalOr;
float radiusSqr;
#ifdef TEST_TRACE
idTimer trace_timer;
trace_timer.Start();
#endif
hit.fraction = 1.0f;
// create two planes orthogonal to each other that intersect along the trace
startDir = end - start;
startDir.Normalize();
startDir.NormalVectors( planes[0].Normal(), planes[1].Normal() );
planes[0][3] = - start * planes[0].Normal();
planes[1][3] = - start * planes[1].Normal();
// create front and end planes so the trace is on the positive sides of both
planes[2] = startDir;
planes[2][3] = - start * planes[2].Normal();
planes[3] = -startDir;
planes[3][3] = - end * planes[3].Normal();
// catagorize each point against the four planes
cullBits = (byte *) _alloca16( tri->numVerts );
SIMDProcessor->TracePointCull( cullBits, totalOr, radius, planes, tri->verts, tri->numVerts );
// if we don't have points on both sides of both the ray planes, no intersection
if ( ( totalOr ^ ( totalOr >> 4 ) ) & 3 ) {
//common->Printf( "nothing crossed the trace planes\n" );
return hit;
}
// if we don't have any points between front and end, no intersection
if ( ( totalOr ^ ( totalOr >> 1 ) ) & 4 ) {
//common->Printf( "trace didn't reach any triangles\n" );
return hit;
}
// scan for triangles that cross both planes
c_testPlanes = 0;
c_testEdges = 0;
c_intersect = 0;
radiusSqr = Square( radius );
startDir = end - start;
if ( !tri->facePlanes || !tri->facePlanesCalculated ) {
R_DeriveFacePlanes( const_cast<srfTriangles_t *>( tri ) );
}
for ( i = 0, j = 0; i < tri->numIndexes; i += 3, j++ ) {
float d1, d2, f, d;
float edgeLengthSqr;
idPlane * plane;
idVec3 point;
idVec3 dir[3];
idVec3 cross;
idVec3 edge;
byte triOr;
// get sidedness info for the triangle
triOr = cullBits[ tri->indexes[i+0] ];
triOr |= cullBits[ tri->indexes[i+1] ];
triOr |= cullBits[ tri->indexes[i+2] ];
// if we don't have points on both sides of both the ray planes, no intersection
if ( ( triOr ^ ( triOr >> 4 ) ) & 3 ) {
continue;
}
// if we don't have any points between front and end, no intersection
if ( ( triOr ^ ( triOr >> 1 ) ) & 4 ) {
continue;
}
c_testPlanes++;
plane = &tri->facePlanes[j];
d1 = plane->Distance( start );
d2 = plane->Distance( end );
if ( d1 <= d2 ) {
continue; // comning at it from behind or parallel
}
if ( d1 < 0.0f ) {
continue; // starts past it
}
if ( d2 > 0.0f ) {
continue; // finishes in front of it
}
f = d1 / ( d1 - d2 );
if ( f < 0.0f ) {
continue; // shouldn't happen
}
if ( f >= hit.fraction ) {
continue; // have already hit something closer
}
c_testEdges++;
// find the exact point of impact with the plane
point = start + f * startDir;
// see if the point is within the three edges
// if radius > 0 the triangle is expanded with a circle in the triangle plane
dir[0] = tri->verts[ tri->indexes[i+0] ].xyz - point;
dir[1] = tri->verts[ tri->indexes[i+1] ].xyz - point;
cross = dir[0].Cross( dir[1] );
d = plane->Normal() * cross;
if ( d > 0.0f ) {
if ( radiusSqr <= 0.0f ) {
continue;
}
edge = tri->verts[ tri->indexes[i+0] ].xyz - tri->verts[ tri->indexes[i+1] ].xyz;
edgeLengthSqr = edge.LengthSqr();
if ( cross.LengthSqr() > edgeLengthSqr * radiusSqr ) {
continue;
}
d = edge * dir[0];
if ( d < 0.0f ) {
edge = tri->verts[ tri->indexes[i+0] ].xyz - tri->verts[ tri->indexes[i+2] ].xyz;
d = edge * dir[0];
if ( d < 0.0f ) {
if ( dir[0].LengthSqr() > radiusSqr ) {
continue;
}
}
} else if ( d > edgeLengthSqr ) {
edge = tri->verts[ tri->indexes[i+1] ].xyz - tri->verts[ tri->indexes[i+2] ].xyz;
d = edge * dir[1];
if ( d < 0.0f ) {
if ( dir[1].LengthSqr() > radiusSqr ) {
continue;
}
}
}
}
dir[2] = tri->verts[ tri->indexes[i+2] ].xyz - point;
cross = dir[1].Cross( dir[2] );
d = plane->Normal() * cross;
if ( d > 0.0f ) {
if ( radiusSqr <= 0.0f ) {
continue;
}
edge = tri->verts[ tri->indexes[i+1] ].xyz - tri->verts[ tri->indexes[i+2] ].xyz;
edgeLengthSqr = edge.LengthSqr();
if ( cross.LengthSqr() > edgeLengthSqr * radiusSqr ) {
continue;
}
d = edge * dir[1];
if ( d < 0.0f ) {
edge = tri->verts[ tri->indexes[i+1] ].xyz - tri->verts[ tri->indexes[i+0] ].xyz;
d = edge * dir[1];
if ( d < 0.0f ) {
if ( dir[1].LengthSqr() > radiusSqr ) {
continue;
}
}
} else if ( d > edgeLengthSqr ) {
edge = tri->verts[ tri->indexes[i+2] ].xyz - tri->verts[ tri->indexes[i+0] ].xyz;
d = edge * dir[2];
if ( d < 0.0f ) {
if ( dir[2].LengthSqr() > radiusSqr ) {
continue;
}
}
}
}
cross = dir[2].Cross( dir[0] );
d = plane->Normal() * cross;
if ( d > 0.0f ) {
if ( radiusSqr <= 0.0f ) {
continue;
}
edge = tri->verts[ tri->indexes[i+2] ].xyz - tri->verts[ tri->indexes[i+0] ].xyz;
edgeLengthSqr = edge.LengthSqr();
if ( cross.LengthSqr() > edgeLengthSqr * radiusSqr ) {
continue;
}
d = edge * dir[2];
if ( d < 0.0f ) {
edge = tri->verts[ tri->indexes[i+2] ].xyz - tri->verts[ tri->indexes[i+1] ].xyz;
d = edge * dir[2];
if ( d < 0.0f ) {
if ( dir[2].LengthSqr() > radiusSqr ) {
continue;
}
}
} else if ( d > edgeLengthSqr ) {
edge = tri->verts[ tri->indexes[i+0] ].xyz - tri->verts[ tri->indexes[i+1] ].xyz;
d = edge * dir[0];
if ( d < 0.0f ) {
if ( dir[0].LengthSqr() > radiusSqr ) {
continue;
}
}
}
}
// we hit it
c_intersect++;
hit.fraction = f;
hit.normal = plane->Normal();
hit.point = point;
hit.indexes[0] = tri->indexes[i];
hit.indexes[1] = tri->indexes[i+1];
hit.indexes[2] = tri->indexes[i+2];
}
#ifdef TEST_TRACE
trace_timer.Stop();
common->Printf( "testVerts:%i c_testPlanes:%i c_testEdges:%i c_intersect:%i msec:%1.4f\n",
tri->numVerts, c_testPlanes, c_testEdges, c_intersect, trace_timer.Milliseconds() );
#endif
return hit;
}
/*
=================
RB_DrawExpandedTriangles
=================
*/
void RB_DrawExpandedTriangles( const srfTriangles_t *tri, const float radius, const idVec3 &vieworg ) {
int i, j, k;
idVec3 dir[6], normal, point;
for ( i = 0; i < tri->numIndexes; i += 3 ) {
idVec3 p[3] = { tri->verts[ tri->indexes[ i + 0 ] ].xyz, tri->verts[ tri->indexes[ i + 1 ] ].xyz, tri->verts[ tri->indexes[ i + 2 ] ].xyz };
dir[0] = p[0] - p[1];
dir[1] = p[1] - p[2];
dir[2] = p[2] - p[0];
normal = dir[0].Cross( dir[1] );
if ( normal * p[0] < normal * vieworg ) {
continue;
}
dir[0] = normal.Cross( dir[0] );
dir[1] = normal.Cross( dir[1] );
dir[2] = normal.Cross( dir[2] );
dir[0].Normalize();
dir[1].Normalize();
dir[2].Normalize();
qglBegin( GL_LINE_LOOP );
for ( j = 0; j < 3; j++ ) {
k = ( j + 1 ) % 3;
dir[4] = ( dir[j] + dir[k] ) * 0.5f;
dir[4].Normalize();
dir[3] = ( dir[j] + dir[4] ) * 0.5f;
dir[3].Normalize();
dir[5] = ( dir[4] + dir[k] ) * 0.5f;
dir[5].Normalize();
point = p[k] + dir[j] * radius;
qglVertex3f( point[0], point[1], point[2] );
point = p[k] + dir[3] * radius;
qglVertex3f( point[0], point[1], point[2] );
point = p[k] + dir[4] * radius;
qglVertex3f( point[0], point[1], point[2] );
point = p[k] + dir[5] * radius;
qglVertex3f( point[0], point[1], point[2] );
point = p[k] + dir[k] * radius;
qglVertex3f( point[0], point[1], point[2] );
}
qglEnd();
}
}
/*
================
RB_ShowTrace
Debug visualization
================
*/
void RB_ShowTrace( drawSurf_t **drawSurfs, int numDrawSurfs ) {
int i;
const srfTriangles_t *tri;
const drawSurf_t *surf;
idVec3 start, end;
idVec3 localStart, localEnd;
localTrace_t hit;
float radius;
if ( r_showTrace.GetInteger() == 0 ) {
return;
}
if ( r_showTrace.GetInteger() == 2 ) {
radius = 5.0f;
} else {
radius = 0.0f;
}
// determine the points of the trace
start = backEnd.viewDef->renderView.vieworg;
end = start + 4000 * backEnd.viewDef->renderView.viewaxis[0];
// check and draw the surfaces
qglDisableClientState( GL_TEXTURE_COORD_ARRAY );
GL_TexEnv( GL_MODULATE );
globalImages->whiteImage->Bind();
// find how many are ambient
for ( i = 0 ; i < numDrawSurfs ; i++ ) {
surf = drawSurfs[i];
tri = surf->geo;
if ( tri == NULL || tri->verts == NULL ) {
continue;
}
// transform the points into local space
R_GlobalPointToLocal( surf->space->modelMatrix, start, localStart );
R_GlobalPointToLocal( surf->space->modelMatrix, end, localEnd );
// check the bounding box
if ( !tri->bounds.Expand( radius ).LineIntersection( localStart, localEnd ) ) {
continue;
}
qglLoadMatrixf( surf->space->modelViewMatrix );
// highlight the surface
GL_State( GLS_SRCBLEND_SRC_ALPHA | GLS_DSTBLEND_ONE_MINUS_SRC_ALPHA );
qglColor4f( 1, 0, 0, 0.25 );
RB_DrawElementsImmediate( tri );
// draw the bounding box
GL_State( GLS_DEPTHFUNC_ALWAYS );
qglColor4f( 1, 1, 1, 1 );
RB_DrawBounds( tri->bounds );
if ( radius != 0.0f ) {
// draw the expanded triangles
qglColor4f( 0.5f, 0.5f, 1.0f, 1.0f );
RB_DrawExpandedTriangles( tri, radius, localStart );
}
// check the exact surfaces
hit = R_LocalTrace( localStart, localEnd, radius, tri );
if ( hit.fraction < 1.0 ) {
qglColor4f( 1, 1, 1, 1 );
RB_DrawBounds( idBounds( hit.point ).Expand( 1 ) );
}
}
}