755 lines
16 KiB
C++
755 lines
16 KiB
C++
/*
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===========================================================================
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Doom 3 GPL Source Code
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Copyright (C) 1999-2011 id Software LLC, a ZeniMax Media company.
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This file is part of the Doom 3 GPL Source Code (?Doom 3 Source Code?).
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Doom 3 Source Code is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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Doom 3 Source Code is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with Doom 3 Source Code. If not, see <http://www.gnu.org/licenses/>.
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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.
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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.
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===========================================================================
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*/
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#include "../precompiled.h"
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#pragma hdrstop
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#include "Winding2D.h"
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/*
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============
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GetAxialBevel
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============
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*/
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bool GetAxialBevel( const idVec3 &plane1, const idVec3 &plane2, const idVec2 &point, idVec3 &bevel ) {
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if ( FLOATSIGNBITSET( plane1.x ) ^ FLOATSIGNBITSET( plane2.x ) ) {
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if ( idMath::Fabs( plane1.x ) > 0.1f && idMath::Fabs( plane2.x ) > 0.1f ) {
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bevel.x = 0.0f;
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if ( FLOATSIGNBITSET( plane1.y ) ) {
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bevel.y = -1.0f;
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}
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else {
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bevel.y = 1.0f;
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}
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bevel.z = - ( point.x * bevel.x + point.y * bevel.y );
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return true;
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}
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}
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if ( FLOATSIGNBITSET( plane1.y ) ^ FLOATSIGNBITSET( plane2.y ) ) {
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if ( idMath::Fabs( plane1.y ) > 0.1f && idMath::Fabs( plane2.y ) > 0.1f ) {
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bevel.y = 0.0f;
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if ( FLOATSIGNBITSET( plane1.x ) ) {
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bevel.x = -1.0f;
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}
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else {
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bevel.x = 1.0f;
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}
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bevel.z = - ( point.x * bevel.x + point.y * bevel.y );
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return true;
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}
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}
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return false;
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}
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/*
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============
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idWinding2D::ExpandForAxialBox
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============
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*/
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void idWinding2D::ExpandForAxialBox( const idVec2 bounds[2] ) {
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int i, j, numPlanes;
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idVec2 v;
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idVec3 planes[MAX_POINTS_ON_WINDING_2D], plane, bevel;
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// get planes for the edges and add bevels
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for ( numPlanes = i = 0; i < numPoints; i++ ) {
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j = (i+1) % numPoints;
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if ( ( p[j] - p[i] ).LengthSqr() < 0.01f ) {
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continue;
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}
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plane = Plane2DFromPoints( p[i], p[j], true );
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if ( i ) {
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if ( GetAxialBevel( planes[numPlanes-1], plane, p[i], bevel ) ) {
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planes[numPlanes++] = bevel;
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}
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}
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assert( numPlanes < MAX_POINTS_ON_WINDING_2D );
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planes[numPlanes++] = plane;
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}
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if ( GetAxialBevel( planes[numPlanes-1], planes[0], p[0], bevel ) ) {
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planes[numPlanes++] = bevel;
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}
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// expand the planes
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for ( i = 0; i < numPlanes; i++ ) {
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v.x = bounds[ FLOATSIGNBITSET( planes[i].x ) ].x;
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v.y = bounds[ FLOATSIGNBITSET( planes[i].y ) ].y;
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planes[i].z += v.x * planes[i].x + v.y * planes[i].y;
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}
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// get intersection points of the planes
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for ( numPoints = i = 0; i < numPlanes; i++ ) {
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if ( Plane2DIntersection( planes[(i+numPlanes-1) % numPlanes], planes[i], p[numPoints] ) ) {
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numPoints++;
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}
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}
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}
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/*
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============
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idWinding2D::Expand
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============
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*/
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void idWinding2D::Expand( const float d ) {
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int i;
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idVec2 edgeNormals[MAX_POINTS_ON_WINDING_2D];
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for ( i = 0; i < numPoints; i++ ) {
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idVec2 &start = p[i];
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idVec2 &end = p[(i+1)%numPoints];
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edgeNormals[i].x = start.y - end.y;
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edgeNormals[i].y = end.x - start.x;
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edgeNormals[i].Normalize();
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edgeNormals[i] *= d;
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}
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for ( i = 0; i < numPoints; i++ ) {
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p[i] += edgeNormals[i] + edgeNormals[(i+numPoints-1)%numPoints];
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}
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}
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/*
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=============
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idWinding2D::Split
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=============
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*/
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int idWinding2D::Split( const idVec3 &plane, const float epsilon, idWinding2D **front, idWinding2D **back ) const {
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float dists[MAX_POINTS_ON_WINDING_2D];
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byte sides[MAX_POINTS_ON_WINDING_2D];
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int counts[3];
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float dot;
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int i, j;
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const idVec2 * p1, *p2;
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idVec2 mid;
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idWinding2D * f;
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idWinding2D * b;
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int maxpts;
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counts[0] = counts[1] = counts[2] = 0;
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// determine sides for each point
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for ( i = 0; i < numPoints; i++ ) {
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dists[i] = dot = plane.x * p[i].x + plane.y * p[i].y + plane.z;
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if ( dot > epsilon ) {
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sides[i] = SIDE_FRONT;
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} else if ( dot < -epsilon ) {
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sides[i] = SIDE_BACK;
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} else {
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sides[i] = SIDE_ON;
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}
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counts[sides[i]]++;
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}
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sides[i] = sides[0];
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dists[i] = dists[0];
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*front = *back = NULL;
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// if nothing at the front of the clipping plane
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if ( !counts[SIDE_FRONT] ) {
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*back = Copy();
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return SIDE_BACK;
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}
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// if nothing at the back of the clipping plane
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if ( !counts[SIDE_BACK] ) {
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*front = Copy();
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return SIDE_FRONT;
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}
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maxpts = numPoints+4; // cant use counts[0]+2 because of fp grouping errors
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*front = f = new idWinding2D;
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*back = b = new idWinding2D;
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for ( i = 0; i < numPoints; i++ ) {
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p1 = &p[i];
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if ( sides[i] == SIDE_ON ) {
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f->p[f->numPoints] = *p1;
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f->numPoints++;
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b->p[b->numPoints] = *p1;
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b->numPoints++;
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continue;
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}
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if ( sides[i] == SIDE_FRONT ) {
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f->p[f->numPoints] = *p1;
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f->numPoints++;
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}
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if ( sides[i] == SIDE_BACK ) {
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b->p[b->numPoints] = *p1;
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b->numPoints++;
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}
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if ( sides[i+1] == SIDE_ON || sides[i+1] == sides[i] ) {
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continue;
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}
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// generate a split point
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p2 = &p[(i+1)%numPoints];
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// always calculate the split going from the same side
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// or minor epsilon issues can happen
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if ( sides[i] == SIDE_FRONT ) {
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dot = dists[i] / ( dists[i] - dists[i+1] );
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for ( j = 0; j < 2; j++ ) {
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// avoid round off error when possible
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if ( plane[j] == 1.0f ) {
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mid[j] = plane.z;
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} else if ( plane[j] == -1.0f ) {
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mid[j] = -plane.z;
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} else {
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mid[j] = (*p1)[j] + dot * ((*p2)[j] - (*p1)[j]);
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}
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}
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} else {
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dot = dists[i+1] / ( dists[i+1] - dists[i] );
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for ( j = 0; j < 2; j++ ) {
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// avoid round off error when possible
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if ( plane[j] == 1.0f ) {
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mid[j] = plane.z;
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} else if ( plane[j] == -1.0f ) {
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mid[j] = -plane.z;
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} else {
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mid[j] = (*p2)[j] + dot * ( (*p1)[j] - (*p2)[j] );
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}
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}
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}
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f->p[f->numPoints] = mid;
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f->numPoints++;
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b->p[b->numPoints] = mid;
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b->numPoints++;
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}
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return SIDE_CROSS;
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}
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/*
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============
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idWinding2D::ClipInPlace
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============
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*/
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bool idWinding2D::ClipInPlace( const idVec3 &plane, const float epsilon, const bool keepOn ) {
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int i, j, maxpts, newNumPoints;
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int sides[MAX_POINTS_ON_WINDING_2D+1], counts[3];
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float dot, dists[MAX_POINTS_ON_WINDING_2D+1];
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idVec2 *p1, *p2, mid, newPoints[MAX_POINTS_ON_WINDING_2D+4];
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counts[SIDE_FRONT] = counts[SIDE_BACK] = counts[SIDE_ON] = 0;
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for ( i = 0; i < numPoints; i++ ) {
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dists[i] = dot = plane.x * p[i].x + plane.y * p[i].y + plane.z;
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if ( dot > epsilon ) {
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sides[i] = SIDE_FRONT;
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} else if ( dot < -epsilon ) {
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sides[i] = SIDE_BACK;
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} else {
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sides[i] = SIDE_ON;
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}
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counts[sides[i]]++;
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}
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sides[i] = sides[0];
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dists[i] = dists[0];
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// if the winding is on the plane and we should keep it
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if ( keepOn && !counts[SIDE_FRONT] && !counts[SIDE_BACK] ) {
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return true;
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}
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if ( !counts[SIDE_FRONT] ) {
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numPoints = 0;
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return false;
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}
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if ( !counts[SIDE_BACK] ) {
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return true;
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}
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maxpts = numPoints + 4; // cant use counts[0]+2 because of fp grouping errors
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newNumPoints = 0;
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for ( i = 0; i < numPoints; i++ ) {
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p1 = &p[i];
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if ( newNumPoints+1 > maxpts ) {
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return true; // can't split -- fall back to original
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}
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if ( sides[i] == SIDE_ON ) {
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newPoints[newNumPoints] = *p1;
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newNumPoints++;
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continue;
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}
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if ( sides[i] == SIDE_FRONT ) {
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newPoints[newNumPoints] = *p1;
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newNumPoints++;
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}
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if ( sides[i+1] == SIDE_ON || sides[i+1] == sides[i] ) {
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continue;
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}
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if ( newNumPoints+1 > maxpts ) {
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return true; // can't split -- fall back to original
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}
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// generate a split point
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p2 = &p[(i+1)%numPoints];
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dot = dists[i] / (dists[i] - dists[i+1]);
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for ( j = 0; j < 2; j++ ) {
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// avoid round off error when possible
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if ( plane[j] == 1.0f ) {
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mid[j] = plane.z;
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} else if ( plane[j] == -1.0f ) {
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mid[j] = -plane.z;
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} else {
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mid[j] = (*p1)[j] + dot * ((*p2)[j] - (*p1)[j]);
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}
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}
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newPoints[newNumPoints] = mid;
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newNumPoints++;
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}
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if ( newNumPoints >= MAX_POINTS_ON_WINDING_2D ) {
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return true;
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}
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numPoints = newNumPoints;
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memcpy( p, newPoints, newNumPoints * sizeof(idVec2) );
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return true;
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}
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/*
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=============
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idWinding2D::Copy
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=============
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*/
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idWinding2D *idWinding2D::Copy( void ) const {
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idWinding2D *w;
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w = new idWinding2D;
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w->numPoints = numPoints;
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memcpy( w->p, p, numPoints * sizeof( p[0] ) );
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return w;
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}
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/*
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=============
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idWinding2D::Reverse
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=============
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*/
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idWinding2D *idWinding2D::Reverse( void ) const {
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idWinding2D *w;
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int i;
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w = new idWinding2D;
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w->numPoints = numPoints;
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for ( i = 0; i < numPoints; i++ ) {
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w->p[ numPoints - i - 1 ] = p[i];
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}
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return w;
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}
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/*
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============
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idWinding2D::GetArea
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============
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*/
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float idWinding2D::GetArea( void ) const {
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int i;
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idVec2 d1, d2;
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float total;
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total = 0.0f;
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for ( i = 2; i < numPoints; i++ ) {
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d1 = p[i-1] - p[0];
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d2 = p[i] - p[0];
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total += d1.x * d2.y - d1.y * d2.x;
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}
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return total * 0.5f;
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}
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/*
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============
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idWinding2D::GetCenter
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============
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*/
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idVec2 idWinding2D::GetCenter( void ) const {
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int i;
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idVec2 center;
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center.Zero();
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for ( i = 0; i < numPoints; i++ ) {
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center += p[i];
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}
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center *= ( 1.0f / numPoints );
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return center;
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}
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/*
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============
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idWinding2D::GetRadius
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============
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*/
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float idWinding2D::GetRadius( const idVec2 ¢er ) const {
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int i;
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float radius, r;
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idVec2 dir;
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radius = 0.0f;
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for ( i = 0; i < numPoints; i++ ) {
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dir = p[i] - center;
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r = dir * dir;
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if ( r > radius ) {
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radius = r;
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}
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}
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return idMath::Sqrt( radius );
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}
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/*
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============
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idWinding2D::GetBounds
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============
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*/
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void idWinding2D::GetBounds( idVec2 bounds[2] ) const {
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int i;
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if ( !numPoints ) {
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bounds[0].x = bounds[0].y = idMath::INFINITY;
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bounds[1].x = bounds[1].y = -idMath::INFINITY;
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return;
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}
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bounds[0] = bounds[1] = p[0];
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for ( i = 1; i < numPoints; i++ ) {
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if ( p[i].x < bounds[0].x ) {
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bounds[0].x = p[i].x;
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} else if ( p[i].x > bounds[1].x ) {
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bounds[1].x = p[i].x;
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}
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if ( p[i].y < bounds[0].y ) {
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bounds[0].y = p[i].y;
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} else if ( p[i].y > bounds[1].y ) {
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bounds[1].y = p[i].y;
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}
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}
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}
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/*
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=============
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idWinding2D::IsTiny
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=============
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*/
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#define EDGE_LENGTH 0.2f
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bool idWinding2D::IsTiny( void ) const {
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int i;
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float len;
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idVec2 delta;
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int edges;
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edges = 0;
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for ( i = 0; i < numPoints; i++ ) {
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delta = p[(i+1)%numPoints] - p[i];
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len = delta.Length();
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if ( len > EDGE_LENGTH ) {
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if ( ++edges == 3 ) {
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return false;
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}
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}
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}
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return true;
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}
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/*
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=============
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idWinding2D::IsHuge
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=============
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*/
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bool idWinding2D::IsHuge( void ) const {
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int i, j;
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for ( i = 0; i < numPoints; i++ ) {
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for ( j = 0; j < 2; j++ ) {
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if ( p[i][j] <= MIN_WORLD_COORD || p[i][j] >= MAX_WORLD_COORD ) {
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return true;
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}
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}
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}
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return false;
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}
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/*
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=============
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idWinding2D::Print
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=============
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*/
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void idWinding2D::Print( void ) const {
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int i;
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for ( i = 0; i < numPoints; i++ ) {
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idLib::common->Printf( "(%5.1f, %5.1f)\n", p[i][0], p[i][1] );
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}
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}
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/*
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=============
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idWinding2D::PlaneDistance
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=============
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*/
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float idWinding2D::PlaneDistance( const idVec3 &plane ) const {
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int i;
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float d, min, max;
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|
|
|
min = idMath::INFINITY;
|
|
max = -min;
|
|
for ( i = 0; i < numPoints; i++ ) {
|
|
d = plane.x * p[i].x + plane.y * p[i].y + plane.z;
|
|
if ( d < min ) {
|
|
min = d;
|
|
if ( FLOATSIGNBITSET( min ) & FLOATSIGNBITNOTSET( max ) ) {
|
|
return 0.0f;
|
|
}
|
|
}
|
|
if ( d > max ) {
|
|
max = d;
|
|
if ( FLOATSIGNBITSET( min ) & FLOATSIGNBITNOTSET( max ) ) {
|
|
return 0.0f;
|
|
}
|
|
}
|
|
}
|
|
if ( FLOATSIGNBITNOTSET( min ) ) {
|
|
return min;
|
|
}
|
|
if ( FLOATSIGNBITSET( max ) ) {
|
|
return max;
|
|
}
|
|
return 0.0f;
|
|
}
|
|
|
|
/*
|
|
=============
|
|
idWinding2D::PlaneSide
|
|
=============
|
|
*/
|
|
int idWinding2D::PlaneSide( const idVec3 &plane, const float epsilon ) const {
|
|
bool front, back;
|
|
int i;
|
|
float d;
|
|
|
|
front = false;
|
|
back = false;
|
|
for ( i = 0; i < numPoints; i++ ) {
|
|
d = plane.x * p[i].x + plane.y * p[i].y + plane.z;
|
|
if ( d < -epsilon ) {
|
|
if ( front ) {
|
|
return SIDE_CROSS;
|
|
}
|
|
back = true;
|
|
continue;
|
|
}
|
|
else if ( d > epsilon ) {
|
|
if ( back ) {
|
|
return SIDE_CROSS;
|
|
}
|
|
front = true;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
if ( back ) {
|
|
return SIDE_BACK;
|
|
}
|
|
if ( front ) {
|
|
return SIDE_FRONT;
|
|
}
|
|
return SIDE_ON;
|
|
}
|
|
|
|
/*
|
|
============
|
|
idWinding2D::PointInside
|
|
============
|
|
*/
|
|
bool idWinding2D::PointInside( const idVec2 &point, const float epsilon ) const {
|
|
int i;
|
|
float d;
|
|
idVec3 plane;
|
|
|
|
for ( i = 0; i < numPoints; i++ ) {
|
|
plane = Plane2DFromPoints( p[i], p[(i+1) % numPoints] );
|
|
d = plane.x * point.x + plane.y * point.y + plane.z;
|
|
if ( d > epsilon ) {
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
============
|
|
idWinding2D::LineIntersection
|
|
============
|
|
*/
|
|
bool idWinding2D::LineIntersection( const idVec2 &start, const idVec2 &end ) const {
|
|
int i, numEdges;
|
|
int sides[MAX_POINTS_ON_WINDING_2D+1], counts[3];
|
|
float d1, d2, epsilon = 0.1f;
|
|
idVec3 plane, edges[2];
|
|
|
|
counts[SIDE_FRONT] = counts[SIDE_BACK] = counts[SIDE_ON] = 0;
|
|
|
|
plane = Plane2DFromPoints( start, end );
|
|
for ( i = 0; i < numPoints; i++ ) {
|
|
d1 = plane.x * p[i].x + plane.y * p[i].y + plane.z;
|
|
if ( d1 > epsilon ) {
|
|
sides[i] = SIDE_FRONT;
|
|
}
|
|
else if ( d1 < -epsilon ) {
|
|
sides[i] = SIDE_BACK;
|
|
}
|
|
else {
|
|
sides[i] = SIDE_ON;
|
|
}
|
|
counts[sides[i]]++;
|
|
}
|
|
sides[i] = sides[0];
|
|
|
|
if ( !counts[SIDE_FRONT] ) {
|
|
return false;
|
|
}
|
|
if ( !counts[SIDE_BACK] ) {
|
|
return false;
|
|
}
|
|
|
|
numEdges = 0;
|
|
for ( i = 0; i < numPoints; i++ ) {
|
|
if ( sides[i] != sides[i+1] && sides[i+1] != SIDE_ON ) {
|
|
edges[numEdges++] = Plane2DFromPoints( p[i], p[(i+1)%numPoints] );
|
|
if ( numEdges >= 2 ) {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if ( numEdges < 2 ) {
|
|
return false;
|
|
}
|
|
|
|
d1 = edges[0].x * start.x + edges[0].y * start.y + edges[0].z;
|
|
d2 = edges[0].x * end.x + edges[0].y * end.y + edges[0].z;
|
|
if ( FLOATSIGNBITNOTSET( d1 ) & FLOATSIGNBITNOTSET( d2 ) ) {
|
|
return false;
|
|
}
|
|
d1 = edges[1].x * start.x + edges[1].y * start.y + edges[1].z;
|
|
d2 = edges[1].x * end.x + edges[1].y * end.y + edges[1].z;
|
|
if ( FLOATSIGNBITNOTSET( d1 ) & FLOATSIGNBITNOTSET( d2 ) ) {
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
============
|
|
idWinding2D::RayIntersection
|
|
============
|
|
*/
|
|
bool idWinding2D::RayIntersection( const idVec2 &start, const idVec2 &dir, float &scale1, float &scale2, int *edgeNums ) const {
|
|
int i, numEdges, localEdgeNums[2];
|
|
int sides[MAX_POINTS_ON_WINDING_2D+1], counts[3];
|
|
float d1, d2, epsilon = 0.1f;
|
|
idVec3 plane, edges[2];
|
|
|
|
scale1 = scale2 = 0.0f;
|
|
counts[SIDE_FRONT] = counts[SIDE_BACK] = counts[SIDE_ON] = 0;
|
|
|
|
plane = Plane2DFromVecs( start, dir );
|
|
for ( i = 0; i < numPoints; i++ ) {
|
|
d1 = plane.x * p[i].x + plane.y * p[i].y + plane.z;
|
|
if ( d1 > epsilon ) {
|
|
sides[i] = SIDE_FRONT;
|
|
}
|
|
else if ( d1 < -epsilon ) {
|
|
sides[i] = SIDE_BACK;
|
|
}
|
|
else {
|
|
sides[i] = SIDE_ON;
|
|
}
|
|
counts[sides[i]]++;
|
|
}
|
|
sides[i] = sides[0];
|
|
|
|
if ( !counts[SIDE_FRONT] ) {
|
|
return false;
|
|
}
|
|
if ( !counts[SIDE_BACK] ) {
|
|
return false;
|
|
}
|
|
|
|
numEdges = 0;
|
|
for ( i = 0; i < numPoints; i++ ) {
|
|
if ( sides[i] != sides[i+1] && sides[i+1] != SIDE_ON ) {
|
|
localEdgeNums[numEdges] = i;
|
|
edges[numEdges++] = Plane2DFromPoints( p[i], p[(i+1)%numPoints] );
|
|
if ( numEdges >= 2 ) {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if ( numEdges < 2 ) {
|
|
return false;
|
|
}
|
|
|
|
d1 = edges[0].x * start.x + edges[0].y * start.y + edges[0].z;
|
|
d2 = - ( edges[0].x * dir.x + edges[0].y * dir.y );
|
|
if ( d2 == 0.0f ) {
|
|
return false;
|
|
}
|
|
scale1 = d1 / d2;
|
|
d1 = edges[1].x * start.x + edges[1].y * start.y + edges[1].z;
|
|
d2 = - ( edges[1].x * dir.x + edges[1].y * dir.y );
|
|
if ( d2 == 0.0f ) {
|
|
return false;
|
|
}
|
|
scale2 = d1 / d2;
|
|
|
|
if ( idMath::Fabs( scale1 ) > idMath::Fabs( scale2 ) ) {
|
|
idSwap( scale1, scale2 );
|
|
idSwap( localEdgeNums[0], localEdgeNums[1] );
|
|
}
|
|
|
|
if ( edgeNums ) {
|
|
edgeNums[0] = localEdgeNums[0];
|
|
edgeNums[1] = localEdgeNums[1];
|
|
}
|
|
return true;
|
|
}
|