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243f400ee2
Signed-off-by: RevoluPowered <gordon@gordonite.tech> Signed-off-by: K. S. Ernest (iFIre) Lee <ernest.lee@chibifire.com>
508 lines
17 KiB
C++
508 lines
17 KiB
C++
/*
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Open Asset Import Library (assimp)
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----------------------------------------------------------------------
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Copyright (c) 2006-2019, assimp team
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All rights reserved.
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Redistribution and use of this software in source and binary forms,
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with or without modification, are permitted provided that the
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following conditions are met:
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* Redistributions of source code must retain the above
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copyright notice, this list of conditions and the
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following disclaimer.
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* Redistributions in binary form must reproduce the above
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copyright notice, this list of conditions and the
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following disclaimer in the documentation and/or other
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materials provided with the distribution.
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* Neither the name of the assimp team, nor the names of its
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contributors may be used to endorse or promote products
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derived from this software without specific prior
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written permission of the assimp team.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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----------------------------------------------------------------------
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*/
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/** @file StandardShapes.cpp
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* @brief Implementation of the StandardShapes class
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*
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* The primitive geometry data comes from
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* http://geometrictools.com/Documentation/PlatonicSolids.pdf.
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*/
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#include <assimp/StandardShapes.h>
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#include <assimp/StringComparison.h>
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#include <stddef.h>
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#include <assimp/Defines.h>
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#include <assimp/mesh.h>
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namespace Assimp {
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# define ADD_TRIANGLE(n0,n1,n2) \
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positions.push_back(n0); \
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positions.push_back(n1); \
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positions.push_back(n2);
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# define ADD_PENTAGON(n0,n1,n2,n3,n4) \
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if (polygons) \
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{ \
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positions.push_back(n0); \
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positions.push_back(n1); \
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positions.push_back(n2); \
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positions.push_back(n3); \
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positions.push_back(n4); \
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} \
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else \
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{ \
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ADD_TRIANGLE(n0, n1, n2) \
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ADD_TRIANGLE(n0, n2, n3) \
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ADD_TRIANGLE(n0, n3, n4) \
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}
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# define ADD_QUAD(n0,n1,n2,n3) \
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if (polygons) \
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{ \
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positions.push_back(n0); \
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positions.push_back(n1); \
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positions.push_back(n2); \
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positions.push_back(n3); \
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} \
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else \
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{ \
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ADD_TRIANGLE(n0, n1, n2) \
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ADD_TRIANGLE(n0, n2, n3) \
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}
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// ------------------------------------------------------------------------------------------------
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// Fast subdivision for a mesh whose verts have a magnitude of 1
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void Subdivide(std::vector<aiVector3D>& positions)
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{
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// assume this to be constant - (fixme: must be 1.0? I think so)
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const ai_real fl1 = positions[0].Length();
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unsigned int origSize = (unsigned int)positions.size();
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for (unsigned int i = 0 ; i < origSize ; i+=3)
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{
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aiVector3D& tv0 = positions[i];
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aiVector3D& tv1 = positions[i+1];
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aiVector3D& tv2 = positions[i+2];
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aiVector3D a = tv0, b = tv1, c = tv2;
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aiVector3D v1 = aiVector3D(a.x+b.x, a.y+b.y, a.z+b.z).Normalize()*fl1;
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aiVector3D v2 = aiVector3D(a.x+c.x, a.y+c.y, a.z+c.z).Normalize()*fl1;
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aiVector3D v3 = aiVector3D(b.x+c.x, b.y+c.y, b.z+c.z).Normalize()*fl1;
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tv0 = v1; tv1 = v3; tv2 = v2; // overwrite the original
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ADD_TRIANGLE(v1, v2, a);
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ADD_TRIANGLE(v2, v3, c);
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ADD_TRIANGLE(v3, v1, b);
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}
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}
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// ------------------------------------------------------------------------------------------------
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// Construct a mesh from given vertex positions
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aiMesh* StandardShapes::MakeMesh(const std::vector<aiVector3D>& positions,
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unsigned int numIndices)
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{
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if (positions.empty() || !numIndices) return NULL;
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// Determine which kinds of primitives the mesh consists of
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aiMesh* out = new aiMesh();
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switch (numIndices) {
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case 1:
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out->mPrimitiveTypes = aiPrimitiveType_POINT;
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break;
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case 2:
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out->mPrimitiveTypes = aiPrimitiveType_LINE;
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break;
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case 3:
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out->mPrimitiveTypes = aiPrimitiveType_TRIANGLE;
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break;
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default:
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out->mPrimitiveTypes = aiPrimitiveType_POLYGON;
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break;
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};
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out->mNumFaces = (unsigned int)positions.size() / numIndices;
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out->mFaces = new aiFace[out->mNumFaces];
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for (unsigned int i = 0, a = 0; i < out->mNumFaces;++i) {
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aiFace& f = out->mFaces[i];
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f.mNumIndices = numIndices;
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f.mIndices = new unsigned int[numIndices];
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for (unsigned int j = 0; i < numIndices; ++i, ++a) {
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f.mIndices[j] = a;
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}
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}
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out->mNumVertices = (unsigned int)positions.size();
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out->mVertices = new aiVector3D[out->mNumVertices];
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::memcpy(out->mVertices,&positions[0],out->mNumVertices*sizeof(aiVector3D));
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return out;
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}
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// ------------------------------------------------------------------------------------------------
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// Construct a mesh with a specific shape (callback)
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aiMesh* StandardShapes::MakeMesh ( unsigned int (*GenerateFunc)(
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std::vector<aiVector3D>&))
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{
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std::vector<aiVector3D> temp;
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unsigned num = (*GenerateFunc)(temp);
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return MakeMesh(temp,num);
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}
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// ------------------------------------------------------------------------------------------------
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// Construct a mesh with a specific shape (callback)
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aiMesh* StandardShapes::MakeMesh ( unsigned int (*GenerateFunc)(
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std::vector<aiVector3D>&, bool))
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{
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std::vector<aiVector3D> temp;
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unsigned num = (*GenerateFunc)(temp,true);
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return MakeMesh(temp,num);
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}
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// ------------------------------------------------------------------------------------------------
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// Construct a mesh with a specific shape (callback)
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aiMesh* StandardShapes::MakeMesh (unsigned int num, void (*GenerateFunc)(
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unsigned int,std::vector<aiVector3D>&))
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{
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std::vector<aiVector3D> temp;
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(*GenerateFunc)(num,temp);
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return MakeMesh(temp,3);
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}
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// ------------------------------------------------------------------------------------------------
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// Build an incosahedron with points.magnitude == 1
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unsigned int StandardShapes::MakeIcosahedron(std::vector<aiVector3D>& positions)
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{
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positions.reserve(positions.size()+60);
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const ai_real t = ( ai_real( 1.0 )+ ai_real( 2.236067977 ) ) / ai_real( 2.0 );
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const ai_real s = std::sqrt(ai_real(1.0) + t*t);
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const aiVector3D v0 = aiVector3D(t,1.0, 0.0)/s;
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const aiVector3D v1 = aiVector3D(-t,1.0, 0.0)/s;
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const aiVector3D v2 = aiVector3D(t,-1.0, 0.0)/s;
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const aiVector3D v3 = aiVector3D(-t,-1.0, 0.0)/s;
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const aiVector3D v4 = aiVector3D(1.0, 0.0, t)/s;
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const aiVector3D v5 = aiVector3D(1.0, 0.0,-t)/s;
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const aiVector3D v6 = aiVector3D(-1.0, 0.0,t)/s;
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const aiVector3D v7 = aiVector3D(-1.0, 0.0,-t)/s;
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const aiVector3D v8 = aiVector3D(0.0, t, 1.0)/s;
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const aiVector3D v9 = aiVector3D(0.0,-t, 1.0)/s;
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const aiVector3D v10 = aiVector3D(0.0, t,-1.0)/s;
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const aiVector3D v11 = aiVector3D(0.0,-t,-1.0)/s;
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ADD_TRIANGLE(v0,v8,v4);
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ADD_TRIANGLE(v0,v5,v10);
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ADD_TRIANGLE(v2,v4,v9);
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ADD_TRIANGLE(v2,v11,v5);
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ADD_TRIANGLE(v1,v6,v8);
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ADD_TRIANGLE(v1,v10,v7);
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ADD_TRIANGLE(v3,v9,v6);
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ADD_TRIANGLE(v3,v7,v11);
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ADD_TRIANGLE(v0,v10,v8);
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ADD_TRIANGLE(v1,v8,v10);
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ADD_TRIANGLE(v2,v9,v11);
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ADD_TRIANGLE(v3,v11,v9);
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ADD_TRIANGLE(v4,v2,v0);
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ADD_TRIANGLE(v5,v0,v2);
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ADD_TRIANGLE(v6,v1,v3);
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ADD_TRIANGLE(v7,v3,v1);
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ADD_TRIANGLE(v8,v6,v4);
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ADD_TRIANGLE(v9,v4,v6);
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ADD_TRIANGLE(v10,v5,v7);
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ADD_TRIANGLE(v11,v7,v5);
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return 3;
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}
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// ------------------------------------------------------------------------------------------------
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// Build a dodecahedron with points.magnitude == 1
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unsigned int StandardShapes::MakeDodecahedron(std::vector<aiVector3D>& positions,
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bool polygons /*= false*/)
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{
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positions.reserve(positions.size()+108);
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const ai_real a = ai_real( 1.0 ) / ai_real(1.7320508);
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const ai_real b = std::sqrt(( ai_real( 3.0 )- ai_real( 2.23606797))/ ai_real( 6.0) );
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const ai_real c = std::sqrt(( ai_real( 3.0 )+ ai_real( 2.23606797f))/ ai_real( 6.0) );
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const aiVector3D v0 = aiVector3D(a,a,a);
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const aiVector3D v1 = aiVector3D(a,a,-a);
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const aiVector3D v2 = aiVector3D(a,-a,a);
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const aiVector3D v3 = aiVector3D(a,-a,-a);
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const aiVector3D v4 = aiVector3D(-a,a,a);
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const aiVector3D v5 = aiVector3D(-a,a,-a);
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const aiVector3D v6 = aiVector3D(-a,-a,a);
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const aiVector3D v7 = aiVector3D(-a,-a,-a);
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const aiVector3D v8 = aiVector3D(b,c,0.0);
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const aiVector3D v9 = aiVector3D(-b,c,0.0);
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const aiVector3D v10 = aiVector3D(b,-c,0.0);
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const aiVector3D v11 = aiVector3D(-b,-c,0.0);
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const aiVector3D v12 = aiVector3D(c, 0.0, b);
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const aiVector3D v13 = aiVector3D(c, 0.0, -b);
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const aiVector3D v14 = aiVector3D(-c, 0.0, b);
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const aiVector3D v15 = aiVector3D(-c, 0.0, -b);
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const aiVector3D v16 = aiVector3D(0.0, b, c);
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const aiVector3D v17 = aiVector3D(0.0, -b, c);
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const aiVector3D v18 = aiVector3D(0.0, b, -c);
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const aiVector3D v19 = aiVector3D(0.0, -b, -c);
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ADD_PENTAGON(v0, v8, v9, v4, v16);
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ADD_PENTAGON(v0, v12, v13, v1, v8);
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ADD_PENTAGON(v0, v16, v17, v2, v12);
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ADD_PENTAGON(v8, v1, v18, v5, v9);
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ADD_PENTAGON(v12, v2, v10, v3, v13);
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ADD_PENTAGON(v16, v4, v14, v6, v17);
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ADD_PENTAGON(v9, v5, v15, v14, v4);
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ADD_PENTAGON(v6, v11, v10, v2, v17);
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ADD_PENTAGON(v3, v19, v18, v1, v13);
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ADD_PENTAGON(v7, v15, v5, v18, v19);
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ADD_PENTAGON(v7, v11, v6, v14, v15);
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ADD_PENTAGON(v7, v19, v3, v10, v11);
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return (polygons ? 5 : 3);
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}
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// ------------------------------------------------------------------------------------------------
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// Build an octahedron with points.magnitude == 1
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unsigned int StandardShapes::MakeOctahedron(std::vector<aiVector3D>& positions)
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{
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positions.reserve(positions.size()+24);
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const aiVector3D v0 = aiVector3D(1.0, 0.0, 0.0) ;
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const aiVector3D v1 = aiVector3D(-1.0, 0.0, 0.0);
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const aiVector3D v2 = aiVector3D(0.0, 1.0, 0.0);
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const aiVector3D v3 = aiVector3D(0.0, -1.0, 0.0);
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const aiVector3D v4 = aiVector3D(0.0, 0.0, 1.0);
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const aiVector3D v5 = aiVector3D(0.0, 0.0, -1.0);
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ADD_TRIANGLE(v4,v0,v2);
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ADD_TRIANGLE(v4,v2,v1);
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ADD_TRIANGLE(v4,v1,v3);
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ADD_TRIANGLE(v4,v3,v0);
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ADD_TRIANGLE(v5,v2,v0);
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ADD_TRIANGLE(v5,v1,v2);
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ADD_TRIANGLE(v5,v3,v1);
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ADD_TRIANGLE(v5,v0,v3);
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return 3;
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}
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// ------------------------------------------------------------------------------------------------
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// Build a tetrahedron with points.magnitude == 1
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unsigned int StandardShapes::MakeTetrahedron(std::vector<aiVector3D>& positions)
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{
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positions.reserve(positions.size()+9);
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const ai_real invThree = ai_real( 1.0 ) / ai_real( 3.0 );
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const ai_real a = ai_real( 1.41421 ) * invThree;
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const ai_real b = ai_real( 2.4494 ) * invThree;
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const aiVector3D v0 = aiVector3D(0.0,0.0,1.0);
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const aiVector3D v1 = aiVector3D(2*a,0,-invThree );
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const aiVector3D v2 = aiVector3D(-a,b,-invThree );
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const aiVector3D v3 = aiVector3D(-a,-b,-invThree );
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ADD_TRIANGLE(v0,v1,v2);
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ADD_TRIANGLE(v0,v2,v3);
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ADD_TRIANGLE(v0,v3,v1);
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ADD_TRIANGLE(v1,v3,v2);
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return 3;
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}
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// ------------------------------------------------------------------------------------------------
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// Build a hexahedron with points.magnitude == 1
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unsigned int StandardShapes::MakeHexahedron(std::vector<aiVector3D>& positions,
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bool polygons /*= false*/)
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{
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positions.reserve(positions.size()+36);
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const ai_real length = ai_real(1.0)/ai_real(1.73205080);
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const aiVector3D v0 = aiVector3D(-1.0,-1.0,-1.0)*length;
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const aiVector3D v1 = aiVector3D(1.0,-1.0,-1.0)*length;
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const aiVector3D v2 = aiVector3D(1.0,1.0,-1.0)*length;
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const aiVector3D v3 = aiVector3D(-1.0,1.0,-1.0)*length;
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const aiVector3D v4 = aiVector3D(-1.0,-1.0,1.0)*length;
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const aiVector3D v5 = aiVector3D(1.0,-1.0,1.0)*length;
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const aiVector3D v6 = aiVector3D(1.0,1.0,1.0)*length;
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const aiVector3D v7 = aiVector3D(-1.0,1.0,1.0)*length;
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ADD_QUAD(v0,v3,v2,v1);
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ADD_QUAD(v0,v1,v5,v4);
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ADD_QUAD(v0,v4,v7,v3);
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ADD_QUAD(v6,v5,v1,v2);
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ADD_QUAD(v6,v2,v3,v7);
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ADD_QUAD(v6,v7,v4,v5);
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return (polygons ? 4 : 3);
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}
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// Cleanup ...
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#undef ADD_TRIANGLE
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#undef ADD_QUAD
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#undef ADD_PENTAGON
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// ------------------------------------------------------------------------------------------------
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// Create a subdivision sphere
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void StandardShapes::MakeSphere(unsigned int tess,
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std::vector<aiVector3D>& positions)
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{
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// Reserve enough storage. Every subdivision
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// splits each triangle in 4, the icosahedron consists of 60 verts
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positions.reserve(positions.size()+60 * integer_pow(4, tess));
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// Construct an icosahedron to start with
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MakeIcosahedron(positions);
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// ... and subdivide it until the requested output
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// tessellation is reached
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for (unsigned int i = 0; i<tess;++i)
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Subdivide(positions);
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}
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// ------------------------------------------------------------------------------------------------
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// Build a cone
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void StandardShapes::MakeCone(ai_real height,ai_real radius1,
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ai_real radius2,unsigned int tess,
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std::vector<aiVector3D>& positions,bool bOpen /*= false */)
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{
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// Sorry, a cone with less than 3 segments makes ABSOLUTELY NO SENSE
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if (tess < 3 || !height)
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return;
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size_t old = positions.size();
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// No negative radii
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radius1 = std::fabs(radius1);
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radius2 = std::fabs(radius2);
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ai_real halfHeight = height / ai_real(2.0);
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// radius1 is always the smaller one
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if (radius2 > radius1)
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{
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std::swap(radius2,radius1);
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halfHeight = -halfHeight;
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}
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else old = SIZE_MAX;
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// Use a large epsilon to check whether the cone is pointy
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if (radius1 < (radius2-radius1)*10e-3)radius1 = 0.0;
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// We will need 3*2 verts per segment + 3*2 verts per segment
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// if the cone is closed
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const unsigned int mem = tess*6 + (!bOpen ? tess*3 * (radius1 ? 2 : 1) : 0);
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positions.reserve(positions.size () + mem);
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// Now construct all segments
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const ai_real angle_delta = (ai_real)AI_MATH_TWO_PI / tess;
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const ai_real angle_max = (ai_real)AI_MATH_TWO_PI;
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ai_real s = 1.0; // std::cos(angle == 0);
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ai_real t = 0.0; // std::sin(angle == 0);
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for (ai_real angle = 0.0; angle < angle_max; )
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|
{
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const aiVector3D v1 = aiVector3D (s * radius1, -halfHeight, t * radius1 );
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const aiVector3D v2 = aiVector3D (s * radius2, halfHeight, t * radius2 );
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|
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const ai_real next = angle + angle_delta;
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ai_real s2 = std::cos(next);
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ai_real t2 = std::sin(next);
|
|
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const aiVector3D v3 = aiVector3D (s2 * radius2, halfHeight, t2 * radius2 );
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const aiVector3D v4 = aiVector3D (s2 * radius1, -halfHeight, t2 * radius1 );
|
|
|
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positions.push_back(v1);
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positions.push_back(v2);
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|
positions.push_back(v3);
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|
positions.push_back(v4);
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|
positions.push_back(v1);
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|
positions.push_back(v3);
|
|
|
|
if (!bOpen)
|
|
{
|
|
// generate the end 'cap'
|
|
positions.push_back(aiVector3D(s * radius2, halfHeight, t * radius2 ));
|
|
positions.push_back(aiVector3D(s2 * radius2, halfHeight, t2 * radius2 ));
|
|
positions.push_back(aiVector3D(0.0, halfHeight, 0.0));
|
|
|
|
|
|
if (radius1)
|
|
{
|
|
// generate the other end 'cap'
|
|
positions.push_back(aiVector3D(s * radius1, -halfHeight, t * radius1 ));
|
|
positions.push_back(aiVector3D(s2 * radius1, -halfHeight, t2 * radius1 ));
|
|
positions.push_back(aiVector3D(0.0, -halfHeight, 0.0));
|
|
|
|
}
|
|
}
|
|
s = s2;
|
|
t = t2;
|
|
angle = next;
|
|
}
|
|
|
|
// Need to flip face order?
|
|
if ( SIZE_MAX != old ) {
|
|
for (size_t p = old; p < positions.size();p += 3) {
|
|
std::swap(positions[p],positions[p+1]);
|
|
}
|
|
}
|
|
}
|
|
|
|
// ------------------------------------------------------------------------------------------------
|
|
// Build a circle
|
|
void StandardShapes::MakeCircle(ai_real radius, unsigned int tess,
|
|
std::vector<aiVector3D>& positions)
|
|
{
|
|
// Sorry, a circle with less than 3 segments makes ABSOLUTELY NO SENSE
|
|
if (tess < 3 || !radius)
|
|
return;
|
|
|
|
radius = std::fabs(radius);
|
|
|
|
// We will need 3 vertices per segment
|
|
positions.reserve(positions.size()+tess*3);
|
|
|
|
const ai_real angle_delta = (ai_real)AI_MATH_TWO_PI / tess;
|
|
const ai_real angle_max = (ai_real)AI_MATH_TWO_PI;
|
|
|
|
ai_real s = 1.0; // std::cos(angle == 0);
|
|
ai_real t = 0.0; // std::sin(angle == 0);
|
|
|
|
for (ai_real angle = 0.0; angle < angle_max; )
|
|
{
|
|
positions.push_back(aiVector3D(s * radius,0.0,t * radius));
|
|
angle += angle_delta;
|
|
s = std::cos(angle);
|
|
t = std::sin(angle);
|
|
positions.push_back(aiVector3D(s * radius,0.0,t * radius));
|
|
|
|
positions.push_back(aiVector3D(0.0,0.0,0.0));
|
|
}
|
|
}
|
|
|
|
} // ! Assimp
|