[3] | 1 | /* |
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| 2 | ----------------------------------------------------------------------------- |
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| 3 | This source file is part of OGRE |
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| 4 | (Object-oriented Graphics Rendering Engine) |
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| 5 | For the latest info, see http://www.ogre3d.org/ |
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| 6 | |
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| 7 | Copyright (c) 2000-2006 Torus Knot Software Ltd |
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| 8 | Copyright (c) 2006 Matthias Fink, netAllied GmbH <matthias.fink@web.de> |
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| 9 | Also see acknowledgements in Readme.html |
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| 10 | |
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| 11 | This program is free software; you can redistribute it and/or modify it under |
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| 12 | the terms of the GNU Lesser General Public License as published by the Free Software |
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| 13 | Foundation; either version 2 of the License, or (at your option) any later |
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| 14 | version. |
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| 15 | |
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| 16 | This program is distributed in the hope that it will be useful, but WITHOUT |
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| 17 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS |
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| 18 | FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. |
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| 19 | |
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| 20 | You should have received a copy of the GNU Lesser General Public License along with |
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| 21 | this program; if not, write to the Free Software Foundation, Inc., 59 Temple |
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| 22 | Place - Suite 330, Boston, MA 02111-1307, USA, or go to |
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| 23 | http://www.gnu.org/copyleft/lesser.txt. |
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| 24 | |
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| 25 | You may alternatively use this source under the terms of a specific version of |
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| 26 | the OGRE Unrestricted License provided you have obtained such a license from |
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| 27 | Torus Knot Software Ltd. |
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| 28 | ----------------------------------------------------------------------------- |
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| 29 | */ |
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| 30 | #include "OgreStableHeaders.h" |
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| 31 | #include "OgreConvexBody.h" |
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| 32 | #include "OgreException.h" |
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| 33 | #include "OgreVector3.h" |
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| 34 | #include <OgreLogManager.h> |
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| 35 | #include <OgreRay.h> |
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| 36 | #include <OgreFrustum.h> |
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| 37 | #include <OgreAxisAlignedBox.h> |
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| 38 | |
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| 39 | |
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| 40 | namespace Ogre |
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| 41 | { |
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| 42 | |
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| 43 | |
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| 44 | //----------------------------------------------------------------------- |
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| 45 | // Statics |
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| 46 | //----------------------------------------------------------------------- |
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| 47 | ConvexBody::PolygonList ConvexBody::msFreePolygons; |
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| 48 | #if OGRE_THREAD_SUPPORT |
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| 49 | boost::recursive_mutex ConvexBody::msFreePolygonsMutex; |
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| 50 | #endif |
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| 51 | //----------------------------------------------------------------------- |
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| 52 | void ConvexBody::_initialisePool() |
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| 53 | { |
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| 54 | OGRE_LOCK_MUTEX(msFreePolygonsMutex) |
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| 55 | |
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| 56 | if (msFreePolygons.empty()) |
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| 57 | { |
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| 58 | const size_t initialSize = 30; |
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| 59 | |
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| 60 | // Initialise polygon pool with 30 polys |
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| 61 | msFreePolygons.resize(initialSize); |
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| 62 | for (size_t i = 0; i < initialSize; ++i) |
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| 63 | { |
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| 64 | msFreePolygons[i] = new Polygon(); |
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| 65 | } |
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| 66 | } |
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| 67 | } |
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| 68 | //----------------------------------------------------------------------- |
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| 69 | void ConvexBody::_destroyPool() |
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| 70 | { |
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| 71 | OGRE_LOCK_MUTEX(msFreePolygonsMutex) |
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| 72 | |
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| 73 | for (PolygonList::iterator i = msFreePolygons.begin(); |
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| 74 | i != msFreePolygons.end(); ++i) |
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| 75 | { |
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| 76 | delete *i; |
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| 77 | } |
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| 78 | msFreePolygons.clear(); |
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| 79 | } |
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| 80 | //----------------------------------------------------------------------- |
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| 81 | Polygon* ConvexBody::allocatePolygon() |
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| 82 | { |
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| 83 | OGRE_LOCK_MUTEX(msFreePolygonsMutex) |
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| 84 | |
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| 85 | if (msFreePolygons.empty()) |
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| 86 | { |
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| 87 | // if we ran out of polys to use, create a new one |
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| 88 | // hopefully this one will return to the pool in due course |
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| 89 | return new Polygon(); |
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| 90 | } |
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| 91 | else |
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| 92 | { |
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| 93 | Polygon* ret = msFreePolygons.back(); |
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| 94 | ret->reset(); |
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| 95 | |
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| 96 | msFreePolygons.pop_back(); |
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| 97 | |
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| 98 | return ret; |
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| 99 | |
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| 100 | } |
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| 101 | } |
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| 102 | //----------------------------------------------------------------------- |
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| 103 | void ConvexBody::freePolygon(Polygon* poly) |
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| 104 | { |
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| 105 | OGRE_LOCK_MUTEX(msFreePolygonsMutex) |
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| 106 | msFreePolygons.push_back(poly); |
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| 107 | } |
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| 108 | //----------------------------------------------------------------------- |
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| 109 | //----------------------------------------------------------------------- |
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| 110 | ConvexBody::ConvexBody() |
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| 111 | { |
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| 112 | // Reserve space for 8 polys, normally 6 faces plus a couple of clips |
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| 113 | mPolygons.reserve(8); |
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| 114 | |
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| 115 | } |
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| 116 | //----------------------------------------------------------------------- |
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| 117 | ConvexBody::~ConvexBody() |
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| 118 | { |
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| 119 | reset(); |
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| 120 | } |
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| 121 | //----------------------------------------------------------------------- |
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| 122 | ConvexBody::ConvexBody( const ConvexBody& cpy ) |
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| 123 | { |
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| 124 | for ( size_t i = 0; i < cpy.getPolygonCount(); ++i ) |
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| 125 | { |
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| 126 | Polygon *p = allocatePolygon(); |
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| 127 | *p = cpy.getPolygon( i ); |
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| 128 | mPolygons.push_back( p ); |
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| 129 | } |
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| 130 | } |
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| 131 | //----------------------------------------------------------------------- |
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| 132 | void ConvexBody::define(const Frustum& frustum) |
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| 133 | { |
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| 134 | // ordering of the points: |
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| 135 | // near (0-3), far (4-7); each (top-right, top-left, bottom-left, bottom-right) |
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| 136 | // 5-----4 |
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| 137 | // /| /| |
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| 138 | // / | / | |
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| 139 | // 1-----0 | |
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| 140 | // | 6--|--7 |
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| 141 | // | / | / |
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| 142 | // |/ |/ |
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| 143 | // 2-----3 |
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| 144 | |
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| 145 | const Vector3 *pts = frustum.getWorldSpaceCorners(); |
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| 146 | |
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| 147 | /// reset ConvexBody |
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| 148 | reset(); |
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| 149 | |
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| 150 | /// update vertices: near, far, left, right, bottom, top; fill in ccw |
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| 151 | Polygon *poly; |
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| 152 | |
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| 153 | // near |
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| 154 | poly = allocatePolygon(); |
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| 155 | poly->insertVertex( pts[0] ); |
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| 156 | poly->insertVertex( pts[1] ); |
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| 157 | poly->insertVertex( pts[2] ); |
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| 158 | poly->insertVertex( pts[3] ); |
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| 159 | mPolygons.push_back( poly ); |
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| 160 | |
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| 161 | // far |
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| 162 | poly = allocatePolygon(); |
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| 163 | poly->insertVertex( pts[5] ); |
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| 164 | poly->insertVertex( pts[4] ); |
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| 165 | poly->insertVertex( pts[7] ); |
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| 166 | poly->insertVertex( pts[6] ); |
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| 167 | mPolygons.push_back( poly ); |
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| 168 | |
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| 169 | // left |
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| 170 | poly = allocatePolygon(); |
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| 171 | poly->insertVertex( pts[5] ); |
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| 172 | poly->insertVertex( pts[6] ); |
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| 173 | poly->insertVertex( pts[2] ); |
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| 174 | poly->insertVertex( pts[1] ); |
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| 175 | mPolygons.push_back( poly ); |
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| 176 | |
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| 177 | // right |
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| 178 | poly = allocatePolygon(); |
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| 179 | poly->insertVertex( pts[4] ); |
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| 180 | poly->insertVertex( pts[0] ); |
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| 181 | poly->insertVertex( pts[3] ); |
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| 182 | poly->insertVertex( pts[7] ); |
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| 183 | mPolygons.push_back( poly ); |
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| 184 | |
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| 185 | // bottom |
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| 186 | poly = allocatePolygon(); |
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| 187 | poly->insertVertex( pts[6] ); |
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| 188 | poly->insertVertex( pts[7] ); |
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| 189 | poly->insertVertex( pts[3] ); |
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| 190 | poly->insertVertex( pts[2] ); |
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| 191 | mPolygons.push_back( poly ); |
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| 192 | |
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| 193 | // top |
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| 194 | poly = allocatePolygon(); |
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| 195 | poly->insertVertex( pts[4] ); |
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| 196 | poly->insertVertex( pts[5] ); |
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| 197 | poly->insertVertex( pts[1] ); |
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| 198 | poly->insertVertex( pts[0] ); |
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| 199 | mPolygons.push_back( poly ); |
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| 200 | } |
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| 201 | //----------------------------------------------------------------------- |
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| 202 | void ConvexBody::define(const AxisAlignedBox& aab) |
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| 203 | { |
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| 204 | // ordering of the AAB points: |
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| 205 | // 1-----2 |
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| 206 | // /| /| |
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| 207 | // / | / | |
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| 208 | // 5-----4 | |
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| 209 | // | 0--|--3 |
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| 210 | // | / | / |
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| 211 | // |/ |/ |
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| 212 | // 6-----7 |
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| 213 | |
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| 214 | const Vector3& min = aab.getMinimum(); |
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| 215 | const Vector3& max = aab.getMaximum(); |
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| 216 | |
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| 217 | Vector3 currentVertex = min; |
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| 218 | |
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| 219 | Polygon *poly; |
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| 220 | |
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| 221 | // reset body |
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| 222 | reset(); |
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| 223 | |
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| 224 | // far |
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| 225 | poly = allocatePolygon(); |
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| 226 | poly->insertVertex( currentVertex ); // 0 |
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| 227 | currentVertex.y = max.y; |
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| 228 | poly->insertVertex( currentVertex ); // 1 |
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| 229 | currentVertex.x = max.x; |
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| 230 | poly->insertVertex( currentVertex ); // 2 |
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| 231 | currentVertex.y = min.y; |
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| 232 | poly->insertVertex( currentVertex ); // 3 |
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| 233 | insertPolygon( poly ); |
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| 234 | |
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| 235 | // right |
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| 236 | poly = allocatePolygon(); |
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| 237 | poly->insertVertex( currentVertex ); // 3 |
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| 238 | currentVertex.y = max.y; |
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| 239 | poly->insertVertex( currentVertex ); // 2 |
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| 240 | currentVertex.z = max.z; |
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| 241 | poly->insertVertex( currentVertex ); // 4 |
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| 242 | currentVertex.y = min.y; |
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| 243 | poly->insertVertex( currentVertex ); // 7 |
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| 244 | insertPolygon( poly ); |
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| 245 | |
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| 246 | // near |
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| 247 | poly = allocatePolygon(); |
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| 248 | poly->insertVertex( currentVertex ); // 7 |
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| 249 | currentVertex.y = max.y; |
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| 250 | poly->insertVertex( currentVertex ); // 4 |
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| 251 | currentVertex.x = min.x; |
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| 252 | poly->insertVertex( currentVertex ); // 5 |
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| 253 | currentVertex.y = min.y; |
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| 254 | poly->insertVertex( currentVertex ); // 6 |
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| 255 | insertPolygon( poly ); |
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| 256 | |
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| 257 | // left |
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| 258 | poly = allocatePolygon(); |
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| 259 | poly->insertVertex( currentVertex ); // 6 |
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| 260 | currentVertex.y = max.y; |
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| 261 | poly->insertVertex( currentVertex ); // 5 |
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| 262 | currentVertex.z = min.z; |
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| 263 | poly->insertVertex( currentVertex ); // 1 |
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| 264 | currentVertex.y = min.y; |
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| 265 | poly->insertVertex( currentVertex ); // 0 |
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| 266 | insertPolygon( poly ); |
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| 267 | |
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| 268 | // bottom |
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| 269 | poly = allocatePolygon(); |
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| 270 | poly->insertVertex( currentVertex ); // 0 |
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| 271 | currentVertex.x = max.x; |
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| 272 | poly->insertVertex( currentVertex ); // 3 |
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| 273 | currentVertex.z = max.z; |
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| 274 | poly->insertVertex( currentVertex ); // 7 |
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| 275 | currentVertex.x = min.x; |
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| 276 | poly->insertVertex( currentVertex ); // 6 |
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| 277 | insertPolygon( poly ); |
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| 278 | |
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| 279 | // top |
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| 280 | poly = allocatePolygon(); |
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| 281 | currentVertex = max; |
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| 282 | poly->insertVertex( currentVertex ); // 4 |
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| 283 | currentVertex.z = min.z; |
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| 284 | poly->insertVertex( currentVertex ); // 2 |
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| 285 | currentVertex.x = min.x; |
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| 286 | poly->insertVertex( currentVertex ); // 1 |
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| 287 | currentVertex.z = max.z; |
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| 288 | poly->insertVertex( currentVertex ); // 5 |
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| 289 | insertPolygon( poly ); |
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| 290 | |
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| 291 | } |
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| 292 | //----------------------------------------------------------------------- |
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| 293 | void ConvexBody::clip(const AxisAlignedBox& aab) |
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| 294 | { |
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| 295 | // ordering of the AAB points: |
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| 296 | // 1-----2 |
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| 297 | // /| /| |
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| 298 | // / | / | |
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| 299 | // 5-----4 | |
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| 300 | // | 0--|--3 |
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| 301 | // | / | / |
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| 302 | // |/ |/ |
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| 303 | // 6-----7 |
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| 304 | |
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| 305 | const Vector3& min = aab.getMinimum(); |
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| 306 | const Vector3& max = aab.getMaximum(); |
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| 307 | |
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| 308 | // clip object for each plane of the AAB |
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| 309 | Plane p; |
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| 310 | |
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| 311 | |
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| 312 | // front |
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| 313 | p.redefine(Vector3::UNIT_Z, max); |
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| 314 | clip(p); |
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| 315 | |
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| 316 | // back |
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| 317 | p.redefine(Vector3::NEGATIVE_UNIT_Z, min); |
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| 318 | clip(p); |
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| 319 | |
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| 320 | // left |
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| 321 | p.redefine(Vector3::NEGATIVE_UNIT_X, min); |
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| 322 | clip(p); |
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| 323 | |
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| 324 | // right |
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| 325 | p.redefine(Vector3::UNIT_X, max); |
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| 326 | clip(p); |
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| 327 | |
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| 328 | // bottom |
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| 329 | p.redefine(Vector3::NEGATIVE_UNIT_Y, min); |
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| 330 | clip(p); |
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| 331 | |
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| 332 | // top |
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| 333 | p.redefine(Vector3::UNIT_Y, max); |
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| 334 | clip(p); |
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| 335 | |
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| 336 | } |
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| 337 | //----------------------------------------------------------------------- |
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| 338 | void ConvexBody::clip(const Frustum& fr) |
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| 339 | { |
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| 340 | // clip the body with each plane |
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| 341 | for ( unsigned short i = 0; i < 6; ++i ) |
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| 342 | { |
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| 343 | // clip, but keep positive space this time since frustum planes are |
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| 344 | // the opposite to other cases (facing inwards rather than outwards) |
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| 345 | clip(fr.getFrustumPlane(i), false); |
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| 346 | } |
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| 347 | } |
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| 348 | //----------------------------------------------------------------------- |
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| 349 | void ConvexBody::clip(const ConvexBody& body) |
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| 350 | { |
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| 351 | if ( this == &body ) |
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| 352 | return; |
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| 353 | |
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| 354 | // for each polygon; clip 'this' with each plane of 'body' |
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| 355 | // front vertex representation is ccw |
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| 356 | |
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| 357 | Plane pl; |
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| 358 | |
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| 359 | for ( size_t iPoly = 0; iPoly < body.getPolygonCount(); ++iPoly ) |
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| 360 | { |
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| 361 | const Polygon& p = body.getPolygon( iPoly ); |
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| 362 | |
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| 363 | OgreAssert( p.getVertexCount() >= 3, "A valid polygon must contain at least three vertices." ); |
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| 364 | |
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| 365 | // set up plane with first three vertices of the polygon (a polygon is always planar) |
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| 366 | pl.redefine( p.getVertex( 0 ), p.getVertex( 1 ), p.getVertex( 2 ) ); |
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| 367 | |
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| 368 | clip(pl); |
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| 369 | } |
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| 370 | } |
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| 371 | //----------------------------------------------------------------------- |
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| 372 | void ConvexBody::extend(const Vector3& pt) |
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| 373 | { |
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| 374 | // Erase all polygons facing towards the point. For all edges that |
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| 375 | // are not removed twice (once in AB and once BA direction) build a |
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| 376 | // convex polygon (triangle) with the point. |
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| 377 | Polygon::EdgeMap edgeMap; |
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| 378 | |
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| 379 | for ( size_t i = 0; i < getPolygonCount(); ++i ) |
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| 380 | { |
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| 381 | const Vector3& normal = getNormal( i ); |
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| 382 | // direction of the point in regard to the polygon |
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| 383 | // the polygon is planar so we can take an arbitrary vertex |
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| 384 | Vector3 ptDir = pt - getVertex( i, 0 ); |
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| 385 | ptDir.normalise(); |
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| 386 | |
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| 387 | // remove polygon if dot product is greater or equals null. |
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| 388 | if ( normal.dotProduct( ptDir ) >= 0 ) |
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| 389 | { |
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| 390 | // store edges (copy them because if the polygon is deleted |
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| 391 | // its vertices are also deleted) |
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| 392 | storeEdgesOfPolygon( i, &edgeMap ); |
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| 393 | |
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| 394 | // remove polygon |
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| 395 | deletePolygon( i ); |
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| 396 | |
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| 397 | // decrement iterator because of deleted polygon |
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| 398 | --i; |
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| 399 | } |
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| 400 | } |
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| 401 | |
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| 402 | // point is already a part of the hull (point lies inside) |
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| 403 | if ( edgeMap.empty() ) |
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| 404 | return; |
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| 405 | |
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| 406 | // remove the edges that are twice in the list (once from each side: AB,BA) |
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| 407 | |
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| 408 | Polygon::EdgeMap::iterator it; |
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| 409 | // iterate from first to the element before the last one |
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| 410 | for (Polygon::EdgeMap::iterator itStart = edgeMap.begin(); |
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| 411 | itStart != edgeMap.end(); ) |
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| 412 | { |
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| 413 | // compare with iterator + 1 to end |
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| 414 | // don't need to skip last entry in itStart since omitted in inner loop |
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| 415 | it = itStart; |
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| 416 | ++it; |
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| 417 | |
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| 418 | bool erased = false; |
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| 419 | // iterate from itStart+1 to the element before the last one |
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| 420 | for ( ; it != edgeMap.end(); ++it ) |
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| 421 | { |
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| 422 | if (itStart->first.positionEquals(it->second) && |
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| 423 | itStart->second.positionEquals(it->first)) |
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| 424 | { |
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| 425 | edgeMap.erase(it); |
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| 426 | // increment itStart before deletion (iterator invalidation) |
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| 427 | Polygon::EdgeMap::iterator delistart = itStart++; |
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| 428 | edgeMap.erase(delistart); |
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| 429 | erased = true; |
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| 430 | |
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| 431 | break; // found and erased |
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| 432 | } |
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| 433 | } |
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| 434 | // increment itStart if we didn't do it when erasing |
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| 435 | if (!erased) |
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| 436 | ++itStart; |
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| 437 | |
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| 438 | } |
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| 439 | |
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| 440 | // use the remaining edges to build triangles with the point |
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| 441 | // the vertices of the edges are in ccw order (edgePtA-edgePtB-point |
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| 442 | // to form a ccw polygon) |
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| 443 | while ( !edgeMap.empty() ) |
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| 444 | { |
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| 445 | Polygon::EdgeMap::iterator it = edgeMap.begin(); |
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| 446 | |
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| 447 | // build polygon it.first, it.second, point |
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| 448 | Polygon *p = allocatePolygon(); |
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| 449 | |
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| 450 | p->insertVertex(it->first); |
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| 451 | p->insertVertex(it->second); |
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| 452 | |
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| 453 | p->insertVertex( pt ); |
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| 454 | // attach polygon to body |
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| 455 | insertPolygon( p ); |
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| 456 | |
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| 457 | // erase the vertices from the list |
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| 458 | // pointers are now held by the polygon |
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| 459 | edgeMap.erase( it ); |
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| 460 | } |
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| 461 | } |
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| 462 | //----------------------------------------------------------------------- |
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| 463 | void ConvexBody::reset( void ) |
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| 464 | { |
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| 465 | for (PolygonList::iterator it = mPolygons.begin(); |
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| 466 | it != mPolygons.end(); ++it) |
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| 467 | { |
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| 468 | freePolygon(*it); |
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| 469 | } |
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| 470 | mPolygons.clear(); |
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| 471 | } |
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| 472 | //----------------------------------------------------------------------- |
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| 473 | size_t ConvexBody::getPolygonCount( void ) const |
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| 474 | { |
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| 475 | return mPolygons.size(); |
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| 476 | } |
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| 477 | //----------------------------------------------------------------------- |
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| 478 | size_t ConvexBody::getVertexCount( size_t poly ) const |
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| 479 | { |
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| 480 | OgreAssert(poly < getPolygonCount(), "Search position out of range" ); |
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| 481 | |
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| 482 | return mPolygons[ poly ]->getVertexCount(); |
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| 483 | } |
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| 484 | //----------------------------------------------------------------------- |
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| 485 | bool ConvexBody::hasClosedHull( void ) const |
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| 486 | { |
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| 487 | // if this map is returned empty, the body is closed |
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| 488 | Polygon::EdgeMap edgeMap = getSingleEdges(); |
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| 489 | |
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| 490 | return edgeMap.empty(); |
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| 491 | } |
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| 492 | //----------------------------------------------------------------------- |
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| 493 | void ConvexBody::mergePolygons( void ) |
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| 494 | { |
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| 495 | // Merge all polygons that lay in the same plane as one big polygon. |
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| 496 | // A convex body does not have two seperate regions (seperated by polygons |
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| 497 | // with different normals) where the same normal occurs, so we can simply |
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| 498 | // search all similar normals of a polygon. Two different options are |
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| 499 | // possible when the normals fit: |
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| 500 | // - the two polygons are neighbors |
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| 501 | // - the two polygons aren't neighbors (but a third, fourth,.. polygon lays |
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| 502 | // in between) |
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| 503 | |
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| 504 | // Signals if the body holds polygons which aren't neighbors but have the same |
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| 505 | // normal. That means another step has to be processed. |
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| 506 | bool bDirty = false; |
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| 507 | |
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| 508 | for ( size_t iPolyA = 0; iPolyA < getPolygonCount(); ++iPolyA ) |
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| 509 | { |
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| 510 | // ?? |
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| 511 | OgreAssert( iPolyA >= 0, "strange..." ); |
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| 512 | |
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| 513 | for ( size_t iPolyB = iPolyA+1; iPolyB < getPolygonCount(); ++iPolyB ) |
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| 514 | { |
---|
| 515 | const Vector3& n1 = getNormal( iPolyA ); |
---|
| 516 | const Vector3& n2 = getNormal( iPolyB ); |
---|
| 517 | |
---|
| 518 | // if the normals point into the same direction |
---|
| 519 | if ( n1.directionEquals( n2, Radian( Degree( 0.00001 ) ) ) ) |
---|
| 520 | { |
---|
| 521 | // indicates if a neighbor has been found and joined |
---|
| 522 | bool bFound = false; |
---|
| 523 | |
---|
| 524 | // search the two fitting vertices (if there are any) for the common edge |
---|
| 525 | const size_t numVerticesA = getVertexCount( iPolyA ); |
---|
| 526 | for ( size_t iVertexA = 0; iVertexA < numVerticesA; ++iVertexA ) |
---|
| 527 | { |
---|
| 528 | const size_t numVerticesB = getVertexCount( iPolyB ); |
---|
| 529 | for ( size_t iVertexB = 0; iVertexB < numVerticesB; ++iVertexB ) |
---|
| 530 | { |
---|
| 531 | const Vector3& aCurrent = getVertex( iPolyA, iVertexA ); |
---|
| 532 | const Vector3& aNext = getVertex( iPolyA, (iVertexA + 1) % getVertexCount( iPolyA ) ); |
---|
| 533 | const Vector3& bCurrent = getVertex( iPolyB, iVertexB ); |
---|
| 534 | const Vector3& bNext = getVertex( iPolyB, (iVertexB + 1) % getVertexCount( iPolyB ) ); |
---|
| 535 | |
---|
| 536 | // if the edge is the same the current vertex of A has to be equal to the next of B and the other |
---|
| 537 | // way round |
---|
| 538 | if ( aCurrent.positionEquals(bNext) && |
---|
| 539 | bCurrent.positionEquals(aNext)) |
---|
| 540 | { |
---|
| 541 | // polygons are neighbors, assemble new one |
---|
| 542 | Polygon *pNew = allocatePolygon(); |
---|
| 543 | |
---|
| 544 | // insert all vertices of A up to the join (including the common vertex, ignoring |
---|
| 545 | // whether the first vertex of A may be a shared vertex) |
---|
| 546 | for ( size_t i = 0; i <= iVertexA; ++i ) |
---|
| 547 | { |
---|
| 548 | pNew->insertVertex( getVertex( iPolyA, i%numVerticesA ) ); |
---|
| 549 | } |
---|
| 550 | |
---|
| 551 | // insert all vertices of B _after_ the join to the end |
---|
| 552 | for ( size_t i = iVertexB + 2; i < numVerticesB; ++i ) |
---|
| 553 | { |
---|
| 554 | pNew->insertVertex( getVertex( iPolyB, i ) ); |
---|
| 555 | } |
---|
| 556 | |
---|
| 557 | // insert all vertices of B from the beginning up to the join (including the common vertex |
---|
| 558 | // and excluding the first vertex if the first is part of the shared edge) |
---|
| 559 | for ( size_t i = 0; i <= iVertexB; ++i ) |
---|
| 560 | { |
---|
| 561 | pNew->insertVertex( getVertex( iPolyB, i%numVerticesB ) ); |
---|
| 562 | } |
---|
| 563 | |
---|
| 564 | // insert all vertices of A _after_ the join to the end |
---|
| 565 | for ( size_t i = iVertexA + 2; i < numVerticesA; ++i ) |
---|
| 566 | { |
---|
| 567 | pNew->insertVertex( getVertex( iPolyA, i ) ); |
---|
| 568 | } |
---|
| 569 | |
---|
| 570 | // in case there are double vertices (in special cases), remove them |
---|
| 571 | for ( size_t i = 0; i < pNew->getVertexCount(); ++i ) |
---|
| 572 | { |
---|
| 573 | const Vector3& a = pNew->getVertex( i ); |
---|
| 574 | const Vector3& b = pNew->getVertex( (i + 1) % pNew->getVertexCount() ); |
---|
| 575 | |
---|
| 576 | // if the two vertices are the same... |
---|
| 577 | if (a.positionEquals(b)) |
---|
| 578 | { |
---|
| 579 | // remove a |
---|
| 580 | pNew->deleteVertex( i ); |
---|
| 581 | |
---|
| 582 | // decrement counter |
---|
| 583 | --i; |
---|
| 584 | } |
---|
| 585 | } |
---|
| 586 | |
---|
| 587 | // delete the two old ones |
---|
| 588 | OgreAssert( iPolyA != iPolyB, "PolyA and polyB are the same!" ); |
---|
| 589 | |
---|
| 590 | // polyB is always higher than polyA, so delete polyB first |
---|
| 591 | deletePolygon( iPolyB ); |
---|
| 592 | deletePolygon( iPolyA ); |
---|
| 593 | |
---|
| 594 | // continue with next (current is deleted, so don't jump to the next after the next) |
---|
| 595 | --iPolyA; |
---|
| 596 | --iPolyB; |
---|
| 597 | |
---|
| 598 | // insert new polygon |
---|
| 599 | insertPolygon( pNew ); |
---|
| 600 | |
---|
| 601 | bFound = true; |
---|
| 602 | break; |
---|
| 603 | } |
---|
| 604 | } |
---|
| 605 | |
---|
| 606 | if ( bFound ) |
---|
| 607 | { |
---|
| 608 | break; |
---|
| 609 | } |
---|
| 610 | } |
---|
| 611 | |
---|
| 612 | if ( bFound == false ) |
---|
| 613 | { |
---|
| 614 | // there are two polygons available with the same normal direction, but they |
---|
| 615 | // could not be merged into one single because of no shared edge |
---|
| 616 | bDirty = true; |
---|
| 617 | break; |
---|
| 618 | } |
---|
| 619 | } |
---|
| 620 | } |
---|
| 621 | } |
---|
| 622 | |
---|
| 623 | // recursion to merge the previous non-neighbors |
---|
| 624 | if ( bDirty ) |
---|
| 625 | { |
---|
| 626 | mergePolygons(); |
---|
| 627 | } |
---|
| 628 | } |
---|
| 629 | //----------------------------------------------------------------------- |
---|
| 630 | const Vector3& ConvexBody::getNormal( size_t poly ) |
---|
| 631 | { |
---|
| 632 | OgreAssert( poly >= 0 && poly < getPolygonCount(), "Search position out of range" ); |
---|
| 633 | |
---|
| 634 | return mPolygons[ poly ]->getNormal(); |
---|
| 635 | } |
---|
| 636 | //----------------------------------------------------------------------- |
---|
| 637 | AxisAlignedBox ConvexBody::getAABB( void ) const |
---|
| 638 | { |
---|
| 639 | AxisAlignedBox aab; |
---|
| 640 | |
---|
| 641 | for ( size_t i = 0; i < getPolygonCount(); ++i ) |
---|
| 642 | { |
---|
| 643 | for ( size_t j = 0; j < getVertexCount( i ); ++j ) |
---|
| 644 | { |
---|
| 645 | aab.merge( getVertex( i, j ) ); |
---|
| 646 | } |
---|
| 647 | } |
---|
| 648 | |
---|
| 649 | return aab; |
---|
| 650 | } |
---|
| 651 | //----------------------------------------------------------------------- |
---|
| 652 | bool ConvexBody::operator == ( const ConvexBody& rhs ) const |
---|
| 653 | { |
---|
| 654 | if ( getPolygonCount() != rhs.getPolygonCount() ) |
---|
| 655 | return false; |
---|
| 656 | |
---|
| 657 | // Compare the polygons. They may not be in correct order. |
---|
| 658 | // A correct convex body does not have identical polygons in its body. |
---|
| 659 | bool *bChecked = new bool[ getPolygonCount() ]; |
---|
| 660 | for ( size_t i=0; i<getPolygonCount(); ++i ) |
---|
| 661 | { |
---|
| 662 | bChecked[ i ] = false; |
---|
| 663 | } |
---|
| 664 | |
---|
| 665 | for ( size_t i=0; i<getPolygonCount(); ++i ) |
---|
| 666 | { |
---|
| 667 | bool bFound = false; |
---|
| 668 | |
---|
| 669 | for ( size_t j=0; j<getPolygonCount(); ++j ) |
---|
| 670 | { |
---|
| 671 | const Polygon& pA = getPolygon( i ); |
---|
| 672 | const Polygon& pB = rhs.getPolygon( j ); |
---|
| 673 | |
---|
| 674 | if ( pA == pB ) |
---|
| 675 | { |
---|
| 676 | bFound = true; |
---|
| 677 | bChecked[ i ] = true; |
---|
| 678 | break; |
---|
| 679 | } |
---|
| 680 | } |
---|
| 681 | |
---|
| 682 | if ( bFound == false ) |
---|
| 683 | { |
---|
| 684 | OGRE_DELETE_ARRAY( bChecked ); |
---|
| 685 | return false; |
---|
| 686 | } |
---|
| 687 | } |
---|
| 688 | |
---|
| 689 | for ( size_t i=0; i<getPolygonCount(); ++i ) |
---|
| 690 | { |
---|
| 691 | if ( bChecked[ i ] != true ) |
---|
| 692 | { |
---|
| 693 | OGRE_DELETE_ARRAY( bChecked ); |
---|
| 694 | return false; |
---|
| 695 | } |
---|
| 696 | } |
---|
| 697 | |
---|
| 698 | OGRE_DELETE_ARRAY( bChecked ); |
---|
| 699 | return true; |
---|
| 700 | } |
---|
| 701 | //----------------------------------------------------------------------- |
---|
| 702 | std::ostream& operator<< ( std::ostream& strm, const ConvexBody& body ) |
---|
| 703 | { |
---|
| 704 | strm << "POLYGON INFO (" << body.getPolygonCount() << ")" << std::endl; |
---|
| 705 | |
---|
| 706 | for ( size_t i = 0; i < body.getPolygonCount(); ++i ) |
---|
| 707 | { |
---|
| 708 | strm << "POLYGON " << i << ", "; |
---|
| 709 | strm << body.getPolygon( i ); |
---|
| 710 | } |
---|
| 711 | |
---|
| 712 | return strm; |
---|
| 713 | } |
---|
| 714 | //----------------------------------------------------------------------- |
---|
| 715 | void ConvexBody::insertPolygon(Polygon* pdata, size_t poly ) |
---|
| 716 | { |
---|
| 717 | OgreAssert(poly <= getPolygonCount(), "Insert position out of range" ); |
---|
| 718 | OgreAssert( pdata != NULL, "Polygon is NULL" ); |
---|
| 719 | |
---|
| 720 | PolygonList::iterator it = mPolygons.begin(); |
---|
| 721 | std::advance(it, poly); |
---|
| 722 | |
---|
| 723 | mPolygons.insert( it, pdata ); |
---|
| 724 | |
---|
| 725 | } |
---|
| 726 | //----------------------------------------------------------------------- |
---|
| 727 | void ConvexBody::insertPolygon(Polygon* pdata) |
---|
| 728 | { |
---|
| 729 | OgreAssert( pdata != NULL, "Polygon is NULL" ); |
---|
| 730 | |
---|
| 731 | mPolygons.push_back( pdata ); |
---|
| 732 | |
---|
| 733 | } |
---|
| 734 | //----------------------------------------------------------------------- |
---|
| 735 | void ConvexBody::insertVertex(size_t poly, const Vector3& vdata, size_t vertex ) |
---|
| 736 | { |
---|
| 737 | OgreAssert(poly < getPolygonCount(), "Search position (polygon) out of range" ); |
---|
| 738 | |
---|
| 739 | mPolygons[poly]->insertVertex(vdata, vertex); |
---|
| 740 | } |
---|
| 741 | //----------------------------------------------------------------------- |
---|
| 742 | void ConvexBody::insertVertex(size_t poly, const Vector3& vdata) |
---|
| 743 | { |
---|
| 744 | OgreAssert(poly < getPolygonCount(), "Search position (polygon) out of range" ); |
---|
| 745 | |
---|
| 746 | mPolygons[poly]->insertVertex(vdata); |
---|
| 747 | } |
---|
| 748 | //----------------------------------------------------------------------- |
---|
| 749 | void ConvexBody::deletePolygon(size_t poly) |
---|
| 750 | { |
---|
| 751 | OgreAssert(poly < getPolygonCount(), "Search position out of range" ); |
---|
| 752 | |
---|
| 753 | PolygonList::iterator it = mPolygons.begin(); |
---|
| 754 | std::advance(it, poly); |
---|
| 755 | |
---|
| 756 | freePolygon(*it); |
---|
| 757 | mPolygons.erase(it); |
---|
| 758 | } |
---|
| 759 | //----------------------------------------------------------------------- |
---|
| 760 | Polygon* ConvexBody::unlinkPolygon(size_t poly) |
---|
| 761 | { |
---|
| 762 | OgreAssert( poly >= 0 && poly < getPolygonCount(), "Search position out of range" ); |
---|
| 763 | |
---|
| 764 | PolygonList::iterator it = mPolygons.begin(); |
---|
| 765 | std::advance(it, poly); |
---|
| 766 | |
---|
| 767 | // safe address |
---|
| 768 | Polygon *pRet = *it; |
---|
| 769 | |
---|
| 770 | // delete entry |
---|
| 771 | mPolygons.erase(it); |
---|
| 772 | |
---|
| 773 | // return polygon pointer |
---|
| 774 | |
---|
| 775 | return pRet; |
---|
| 776 | } |
---|
| 777 | //----------------------------------------------------------------------- |
---|
| 778 | void ConvexBody::moveDataFromBody(ConvexBody& body) |
---|
| 779 | { |
---|
| 780 | body.mPolygons.swap(this->mPolygons); |
---|
| 781 | } |
---|
| 782 | //----------------------------------------------------------------------- |
---|
| 783 | void ConvexBody::deleteVertex(size_t poly, size_t vertex) |
---|
| 784 | { |
---|
| 785 | OgreAssert(poly < getPolygonCount(), "Search position out of range" ); |
---|
| 786 | |
---|
| 787 | mPolygons[poly]->deleteVertex(vertex); |
---|
| 788 | } |
---|
| 789 | //----------------------------------------------------------------------- |
---|
| 790 | const Polygon& ConvexBody::getPolygon(size_t poly) const |
---|
| 791 | { |
---|
| 792 | OgreAssert(poly < getPolygonCount(), "Search position out of range"); |
---|
| 793 | |
---|
| 794 | return *mPolygons[poly]; |
---|
| 795 | } |
---|
| 796 | //----------------------------------------------------------------------- |
---|
| 797 | void ConvexBody::setPolygon(Polygon* pdata, size_t poly) |
---|
| 798 | { |
---|
| 799 | OgreAssert(poly < getPolygonCount(), "Search position out of range" ); |
---|
| 800 | OgreAssert(pdata != NULL, "Polygon is NULL" ); |
---|
| 801 | |
---|
| 802 | if (pdata != mPolygons[poly]) |
---|
| 803 | { |
---|
| 804 | // delete old polygon |
---|
| 805 | freePolygon(mPolygons[ poly ]); |
---|
| 806 | |
---|
| 807 | // set new polygon |
---|
| 808 | mPolygons[poly] = pdata; |
---|
| 809 | } |
---|
| 810 | } |
---|
| 811 | //----------------------------------------------------------------------- |
---|
| 812 | const Vector3& ConvexBody::getVertex(size_t poly, size_t vertex) const |
---|
| 813 | { |
---|
| 814 | OgreAssert( poly >= 0 && poly < getPolygonCount(), "Search position out of range" ); |
---|
| 815 | |
---|
| 816 | return mPolygons[poly]->getVertex(vertex); |
---|
| 817 | } |
---|
| 818 | //----------------------------------------------------------------------- |
---|
| 819 | void ConvexBody::setVertex(size_t poly, const Vector3& vdata, size_t vertex) |
---|
| 820 | { |
---|
| 821 | OgreAssert(poly < getPolygonCount(), "Search position out of range"); |
---|
| 822 | |
---|
| 823 | mPolygons[poly]->setVertex(vdata, vertex); |
---|
| 824 | } |
---|
| 825 | //----------------------------------------------------------------------- |
---|
| 826 | void ConvexBody::storeEdgesOfPolygon(size_t poly, Polygon::EdgeMap *edgeMap ) const |
---|
| 827 | { |
---|
| 828 | OgreAssert(poly <= getPolygonCount(), "Search position out of range" ); |
---|
| 829 | OgreAssert( edgeMap != NULL, "TEdgeMap ptr is NULL" ); |
---|
| 830 | |
---|
| 831 | mPolygons[poly]->storeEdges(edgeMap); |
---|
| 832 | } |
---|
| 833 | //----------------------------------------------------------------------- |
---|
| 834 | Polygon::EdgeMap ConvexBody::getSingleEdges() const |
---|
| 835 | { |
---|
| 836 | Polygon::EdgeMap edgeMap; |
---|
| 837 | |
---|
| 838 | // put all edges of all polygons into a list every edge has to be |
---|
| 839 | // walked in each direction once |
---|
| 840 | for ( size_t i = 0; i < getPolygonCount(); ++i ) |
---|
| 841 | { |
---|
| 842 | const Polygon& p = getPolygon( i ); |
---|
| 843 | |
---|
| 844 | for ( size_t j = 0; j < p.getVertexCount(); ++j ) |
---|
| 845 | { |
---|
| 846 | const Vector3& a = p.getVertex( j ); |
---|
| 847 | const Vector3& b = p.getVertex( ( j + 1 ) % p.getVertexCount() ); |
---|
| 848 | |
---|
| 849 | edgeMap.insert( Polygon::Edge( a, b ) ); |
---|
| 850 | } |
---|
| 851 | } |
---|
| 852 | |
---|
| 853 | // search corresponding parts |
---|
| 854 | Polygon::EdgeMap::iterator it; |
---|
| 855 | Polygon::EdgeMap::iterator itStart; |
---|
| 856 | Polygon::EdgeMap::const_iterator itEnd; |
---|
| 857 | while( !edgeMap.empty() ) |
---|
| 858 | { |
---|
| 859 | it = edgeMap.begin(); ++it; // start one element after itStart |
---|
| 860 | itStart = edgeMap.begin(); // the element to be compared with the others |
---|
| 861 | itEnd = edgeMap.end(); // beyond the last element |
---|
| 862 | |
---|
| 863 | bool bFound = false; |
---|
| 864 | |
---|
| 865 | for ( ; it != itEnd; ++it ) |
---|
| 866 | { |
---|
| 867 | if (itStart->first.positionEquals(it->second) && |
---|
| 868 | itStart->second.positionEquals(it->first)) |
---|
| 869 | { |
---|
| 870 | // erase itStart and it |
---|
| 871 | edgeMap.erase( it ); |
---|
| 872 | edgeMap.erase( itStart ); |
---|
| 873 | |
---|
| 874 | bFound = true; |
---|
| 875 | |
---|
| 876 | break; // found |
---|
| 877 | } |
---|
| 878 | } |
---|
| 879 | |
---|
| 880 | if ( bFound == false ) |
---|
| 881 | { |
---|
| 882 | break; // not all edges could be matched |
---|
| 883 | // body is not closed |
---|
| 884 | } |
---|
| 885 | } |
---|
| 886 | |
---|
| 887 | return edgeMap; |
---|
| 888 | } |
---|
| 889 | //----------------------------------------------------------------------- |
---|
| 890 | void ConvexBody::allocateSpace( size_t numPolygons, size_t numVertices ) |
---|
| 891 | { |
---|
| 892 | reset(); |
---|
| 893 | |
---|
| 894 | // allocate numPolygons polygons with each numVertices vertices |
---|
| 895 | for ( size_t iPoly = 0; iPoly < numPolygons; ++iPoly ) |
---|
| 896 | { |
---|
| 897 | Polygon *poly = allocatePolygon(); |
---|
| 898 | |
---|
| 899 | for ( size_t iVertex = 0; iVertex < numVertices; ++iVertex ) |
---|
| 900 | { |
---|
| 901 | poly->insertVertex( Vector3::ZERO ); |
---|
| 902 | } |
---|
| 903 | |
---|
| 904 | mPolygons.push_back( poly ); |
---|
| 905 | } |
---|
| 906 | } |
---|
| 907 | //----------------------------------------------------------------------- |
---|
| 908 | void ConvexBody::clip( const Plane& pl, bool keepNegative ) |
---|
| 909 | { |
---|
| 910 | if ( getPolygonCount() == 0 ) |
---|
| 911 | return; |
---|
| 912 | |
---|
| 913 | // current will be used as the reference body |
---|
| 914 | ConvexBody current; |
---|
| 915 | current.moveDataFromBody(*this); |
---|
| 916 | |
---|
| 917 | OgreAssert( this->getPolygonCount() == 0, "Body not empty!" ); |
---|
| 918 | OgreAssert( current.getPolygonCount() != 0, "Body empty!" ); |
---|
| 919 | |
---|
| 920 | // holds all intersection edges for the different polygons |
---|
| 921 | Polygon::EdgeMap intersectionEdges; |
---|
| 922 | |
---|
| 923 | // clip all polygons by the intersection plane |
---|
| 924 | // add only valid or intersected polygons to *this |
---|
| 925 | for ( size_t iPoly = 0; iPoly < current.getPolygonCount(); ++iPoly ) |
---|
| 926 | { |
---|
| 927 | |
---|
| 928 | // fetch vertex count and ignore polygons with less than three vertices |
---|
| 929 | // the polygon is not valid and won't be added |
---|
| 930 | const size_t vertexCount = current.getVertexCount( iPoly ); |
---|
| 931 | if ( vertexCount < 3 ) |
---|
| 932 | continue; |
---|
| 933 | |
---|
| 934 | // current polygon |
---|
| 935 | const Polygon& p = current.getPolygon( iPoly ); |
---|
| 936 | |
---|
| 937 | // the polygon to assemble |
---|
| 938 | Polygon *pNew = allocatePolygon(); |
---|
| 939 | |
---|
| 940 | // the intersection polygon (indeed it's an edge or it's empty) |
---|
| 941 | Polygon *pIntersect = allocatePolygon(); |
---|
| 942 | |
---|
| 943 | // check if polygons lie inside or outside (or on the plane) |
---|
| 944 | // for each vertex check where it is situated in regard to the plane |
---|
| 945 | // three possibilities appear: |
---|
| 946 | Plane::Side clipSide = keepNegative ? Plane::POSITIVE_SIDE : Plane::NEGATIVE_SIDE; |
---|
| 947 | // - side is clipSide: vertex will be clipped |
---|
| 948 | // - side is !clipSide: vertex will be untouched |
---|
| 949 | // - side is NOSIDE: vertex will be untouched |
---|
| 950 | Plane::Side *side = new Plane::Side[ vertexCount ]; |
---|
| 951 | for ( size_t iVertex = 0; iVertex < vertexCount; ++iVertex ) |
---|
| 952 | { |
---|
| 953 | side[ iVertex ] = pl.getSide( p.getVertex( iVertex ) ); |
---|
| 954 | } |
---|
| 955 | |
---|
| 956 | // now we check the side combinations for the current and the next vertex |
---|
| 957 | // four different combinations exist: |
---|
| 958 | // - both points inside (or on the plane): keep the second (add it to the body) |
---|
| 959 | // - both points outside: discard both (don't add them to the body) |
---|
| 960 | // - first vertex is inside, second is outside: add the intersection point |
---|
| 961 | // - first vertex is outside, second is inside: add the intersection point, then the second |
---|
| 962 | for ( size_t iVertex = 0; iVertex < vertexCount; ++iVertex ) |
---|
| 963 | { |
---|
| 964 | // determine the next vertex |
---|
| 965 | size_t iNextVertex = ( iVertex + 1 ) % vertexCount; |
---|
| 966 | |
---|
| 967 | const Vector3& vCurrent = p.getVertex( iVertex ); |
---|
| 968 | const Vector3& vNext = p.getVertex( iNextVertex ); |
---|
| 969 | |
---|
| 970 | // case 1: both points inside (store next) |
---|
| 971 | if ( side[ iVertex ] != clipSide && // NEGATIVE or NONE |
---|
| 972 | side[ iNextVertex ] != clipSide ) // NEGATIVE or NONE |
---|
| 973 | { |
---|
| 974 | // keep the second |
---|
| 975 | pNew->insertVertex( vNext ); |
---|
| 976 | } |
---|
| 977 | |
---|
| 978 | // case 3: inside -> outside (store intersection) |
---|
| 979 | else if ( side[ iVertex ] != clipSide && |
---|
| 980 | side[ iNextVertex ] == clipSide ) |
---|
| 981 | { |
---|
| 982 | // Do an intersection with the plane. We use a ray with a start point and a direction. |
---|
| 983 | // The ray is forced to hit the plane with any option available (eigher current or next |
---|
| 984 | // is the starting point) |
---|
| 985 | |
---|
| 986 | // intersect from the outside vertex towards the inside one |
---|
| 987 | Vector3 vDirection = vCurrent - vNext; |
---|
| 988 | vDirection.normalise(); |
---|
| 989 | Ray ray( vNext, vDirection ); |
---|
| 990 | std::pair< bool, Real > intersect = ray.intersects( pl ); |
---|
| 991 | |
---|
| 992 | // store intersection |
---|
| 993 | if ( intersect.first ) |
---|
| 994 | { |
---|
| 995 | // convert distance to vector |
---|
| 996 | Vector3 vIntersect = ray.getPoint( intersect.second ); |
---|
| 997 | |
---|
| 998 | // store intersection |
---|
| 999 | pNew->insertVertex( vIntersect ); |
---|
| 1000 | pIntersect->insertVertex( vIntersect ); |
---|
| 1001 | } |
---|
| 1002 | } |
---|
| 1003 | |
---|
| 1004 | // case 4: outside -> inside (store intersection, store next) |
---|
| 1005 | else if ( side[ iVertex ] == clipSide && |
---|
| 1006 | side[ iNextVertex ] != clipSide ) |
---|
| 1007 | { |
---|
| 1008 | // Do an intersection with the plane. We use a ray with a start point and a direction. |
---|
| 1009 | // The ray is forced to hit the plane with any option available (eigher current or next |
---|
| 1010 | // is the starting point) |
---|
| 1011 | |
---|
| 1012 | // intersect from the outside vertex towards the inside one |
---|
| 1013 | Vector3 vDirection = vNext - vCurrent; |
---|
| 1014 | vDirection.normalise(); |
---|
| 1015 | Ray ray( vCurrent, vDirection ); |
---|
| 1016 | std::pair< bool, Real > intersect = ray.intersects( pl ); |
---|
| 1017 | |
---|
| 1018 | // store intersection |
---|
| 1019 | if ( intersect.first ) |
---|
| 1020 | { |
---|
| 1021 | // convert distance to vector |
---|
| 1022 | Vector3 vIntersect = ray.getPoint( intersect.second ); |
---|
| 1023 | |
---|
| 1024 | // store intersection |
---|
| 1025 | pNew->insertVertex( vIntersect ); |
---|
| 1026 | pIntersect->insertVertex( vIntersect ); |
---|
| 1027 | } |
---|
| 1028 | |
---|
| 1029 | pNew->insertVertex( vNext ); |
---|
| 1030 | |
---|
| 1031 | } |
---|
| 1032 | // else: |
---|
| 1033 | // case 2: both outside (do nothing) |
---|
| 1034 | |
---|
| 1035 | } |
---|
| 1036 | |
---|
| 1037 | // insert the polygon only, if at least three vertices are present |
---|
| 1038 | if ( pNew->getVertexCount() >= 3 ) |
---|
| 1039 | { |
---|
| 1040 | // in case there are double vertices, remove them |
---|
| 1041 | pNew->removeDuplicates(); |
---|
| 1042 | |
---|
| 1043 | // in case there are still at least three vertices, insert the polygon |
---|
| 1044 | if ( pNew->getVertexCount() >= 3 ) |
---|
| 1045 | { |
---|
| 1046 | this->insertPolygon( pNew ); |
---|
| 1047 | } |
---|
| 1048 | else |
---|
| 1049 | { |
---|
| 1050 | // delete pNew because it's empty or invalid |
---|
| 1051 | freePolygon(pNew); |
---|
| 1052 | pNew = 0; |
---|
| 1053 | } |
---|
| 1054 | } |
---|
| 1055 | else |
---|
| 1056 | { |
---|
| 1057 | // delete pNew because it's empty or invalid |
---|
| 1058 | freePolygon(pNew); |
---|
| 1059 | pNew = 0; |
---|
| 1060 | } |
---|
| 1061 | |
---|
| 1062 | // insert intersection polygon only, if there are two vertices present |
---|
| 1063 | if ( pIntersect->getVertexCount() == 2 ) |
---|
| 1064 | { |
---|
| 1065 | intersectionEdges.insert( Polygon::Edge( pIntersect->getVertex( 0 ), |
---|
| 1066 | pIntersect->getVertex( 1 ) ) ); |
---|
| 1067 | } |
---|
| 1068 | |
---|
| 1069 | // delete intersection polygon |
---|
| 1070 | // vertices were copied (if there were any) |
---|
| 1071 | freePolygon(pIntersect); |
---|
| 1072 | pIntersect = 0; |
---|
| 1073 | |
---|
| 1074 | // delete side info |
---|
| 1075 | OGRE_DELETE_ARRAY( side ); |
---|
| 1076 | } |
---|
| 1077 | |
---|
| 1078 | // if the polygon was partially clipped, close it |
---|
| 1079 | // at least three edges are needed for a polygon |
---|
| 1080 | if ( intersectionEdges.size() >= 3 ) |
---|
| 1081 | { |
---|
| 1082 | Polygon *pClosing = allocatePolygon(); |
---|
| 1083 | |
---|
| 1084 | // Analyze the intersection list and insert the intersection points in ccw order |
---|
| 1085 | // Each point is twice in the list because of the fact that we have a convex body |
---|
| 1086 | // with convex polygons. All we have to do is order the edges (an even-odd pair) |
---|
| 1087 | // in a ccw order. The plane normal shows us the direction. |
---|
| 1088 | Polygon::EdgeMap::iterator it = intersectionEdges.begin(); |
---|
| 1089 | |
---|
| 1090 | // check the cross product of the first two edges |
---|
| 1091 | const Vector3& vFirst = it->first; |
---|
| 1092 | const Vector3& vSecond = it->second; |
---|
| 1093 | |
---|
| 1094 | // remove inserted edge |
---|
| 1095 | intersectionEdges.erase( it ); |
---|
| 1096 | |
---|
| 1097 | Vector3 vNext; |
---|
| 1098 | |
---|
| 1099 | // find mating edge |
---|
| 1100 | if (findAndEraseEdgePair(vSecond, intersectionEdges, vNext)) |
---|
| 1101 | { |
---|
| 1102 | // detect the orientation |
---|
| 1103 | // the polygon must have the same normal direction as the plane and then n |
---|
| 1104 | Vector3 vCross = ( vFirst - vSecond ).crossProduct( vNext - vSecond ); |
---|
| 1105 | bool frontside = ( pl.normal ).directionEquals( vCross, Degree( 1 ) ); |
---|
| 1106 | |
---|
| 1107 | // first inserted vertex |
---|
| 1108 | Vector3 firstVertex; |
---|
| 1109 | // currently inserted vertex |
---|
| 1110 | Vector3 currentVertex; |
---|
| 1111 | // direction equals -> front side (walk ccw) |
---|
| 1112 | if ( frontside ) |
---|
| 1113 | { |
---|
| 1114 | // start with next as first vertex, then second, then first and continue with first to walk ccw |
---|
| 1115 | pClosing->insertVertex( vNext ); |
---|
| 1116 | pClosing->insertVertex( vSecond ); |
---|
| 1117 | pClosing->insertVertex( vFirst ); |
---|
| 1118 | firstVertex = vNext; |
---|
| 1119 | currentVertex = vFirst; |
---|
| 1120 | |
---|
| 1121 | #ifdef _DEBUG_INTERSECTION_LIST |
---|
| 1122 | std::cout << "Plane: n=" << pl.normal << ", d=" << pl.d << std::endl; |
---|
| 1123 | std::cout << "First inserted vertex: " << *next << std::endl; |
---|
| 1124 | std::cout << "Second inserted vertex: " << *vSecond << std::endl; |
---|
| 1125 | std::cout << "Third inserted vertex: " << *vFirst << std::endl; |
---|
| 1126 | #endif |
---|
| 1127 | } |
---|
| 1128 | // direction does not equal -> back side (walk cw) |
---|
| 1129 | else |
---|
| 1130 | { |
---|
| 1131 | // start with first as first vertex, then second, then next and continue with next to walk ccw |
---|
| 1132 | pClosing->insertVertex( vFirst ); |
---|
| 1133 | pClosing->insertVertex( vSecond ); |
---|
| 1134 | pClosing->insertVertex( vNext ); |
---|
| 1135 | firstVertex = vFirst; |
---|
| 1136 | currentVertex = vNext; |
---|
| 1137 | |
---|
| 1138 | #ifdef _DEBUG_INTERSECTION_LIST |
---|
| 1139 | std::cout << "Plane: n=" << pl.normal << ", d=" << pl.d << std::endl; |
---|
| 1140 | std::cout << "First inserted vertex: " << *vFirst << std::endl; |
---|
| 1141 | std::cout << "Second inserted vertex: " << *vSecond << std::endl; |
---|
| 1142 | std::cout << "Third inserted vertex: " << *next << std::endl; |
---|
| 1143 | #endif |
---|
| 1144 | } |
---|
| 1145 | |
---|
| 1146 | // search mating edges that have a point in common |
---|
| 1147 | // continue this operation as long as edges are present |
---|
| 1148 | while ( !intersectionEdges.empty() ) |
---|
| 1149 | { |
---|
| 1150 | |
---|
| 1151 | if (findAndEraseEdgePair(currentVertex, intersectionEdges, vNext)) |
---|
| 1152 | { |
---|
| 1153 | // insert only if it's not the last (which equals the first) vertex |
---|
| 1154 | if ( !intersectionEdges.empty() ) |
---|
| 1155 | { |
---|
| 1156 | currentVertex = vNext; |
---|
| 1157 | pClosing->insertVertex( vNext ); |
---|
| 1158 | } |
---|
| 1159 | } |
---|
| 1160 | else |
---|
| 1161 | { |
---|
| 1162 | // degenerated... |
---|
| 1163 | break; |
---|
| 1164 | } |
---|
| 1165 | |
---|
| 1166 | } // while intersectionEdges not empty |
---|
| 1167 | |
---|
| 1168 | // insert polygon (may be degenerated!) |
---|
| 1169 | this->insertPolygon( pClosing ); |
---|
| 1170 | |
---|
| 1171 | } |
---|
| 1172 | // mating intersection edge NOT found! |
---|
| 1173 | else |
---|
| 1174 | { |
---|
| 1175 | freePolygon(pClosing); |
---|
| 1176 | } |
---|
| 1177 | |
---|
| 1178 | } // if intersectionEdges contains more than three elements |
---|
| 1179 | } |
---|
| 1180 | //----------------------------------------------------------------------- |
---|
| 1181 | bool ConvexBody::findAndEraseEdgePair(const Vector3& vec, |
---|
| 1182 | Polygon::EdgeMap& intersectionEdges, Vector3& vNext ) const |
---|
| 1183 | { |
---|
| 1184 | Polygon::EdgeMap::iterator it = intersectionEdges.begin(); |
---|
| 1185 | |
---|
| 1186 | for (Polygon::EdgeMap::iterator it = intersectionEdges.begin(); |
---|
| 1187 | it != intersectionEdges.end(); ++it) |
---|
| 1188 | { |
---|
| 1189 | if (it->first.positionEquals(vec)) |
---|
| 1190 | { |
---|
| 1191 | vNext = it->second; |
---|
| 1192 | |
---|
| 1193 | // erase found edge |
---|
| 1194 | intersectionEdges.erase( it ); |
---|
| 1195 | |
---|
| 1196 | return true; // found! |
---|
| 1197 | } |
---|
| 1198 | else if (it->second.positionEquals(vec)) |
---|
| 1199 | { |
---|
| 1200 | vNext = it->first; |
---|
| 1201 | |
---|
| 1202 | // erase found edge |
---|
| 1203 | intersectionEdges.erase( it ); |
---|
| 1204 | |
---|
| 1205 | return true; // found! |
---|
| 1206 | } |
---|
| 1207 | } |
---|
| 1208 | |
---|
| 1209 | return false; // not found! |
---|
| 1210 | } |
---|
| 1211 | //----------------------------------------------------------------------- |
---|
| 1212 | void ConvexBody::logInfo( void ) const |
---|
| 1213 | { |
---|
| 1214 | std::stringstream ssOut( std::stringstream::out ); |
---|
| 1215 | ssOut << *this; |
---|
| 1216 | |
---|
| 1217 | Ogre::LogManager::getSingleton().logMessage( Ogre::LML_NORMAL, ssOut.str() ); |
---|
| 1218 | } |
---|
| 1219 | } |
---|
| 1220 | |
---|