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Diffstat (limited to 'libs/assimp/code/AssetLib/Blender/BlenderTessellator.cpp')
| -rw-r--r-- | libs/assimp/code/AssetLib/Blender/BlenderTessellator.cpp | 532 |
1 files changed, 532 insertions, 0 deletions
diff --git a/libs/assimp/code/AssetLib/Blender/BlenderTessellator.cpp b/libs/assimp/code/AssetLib/Blender/BlenderTessellator.cpp new file mode 100644 index 0000000..d3d463e --- /dev/null +++ b/libs/assimp/code/AssetLib/Blender/BlenderTessellator.cpp @@ -0,0 +1,532 @@ +/* +Open Asset Import Library (assimp) +---------------------------------------------------------------------- + +Copyright (c) 2006-2022, assimp team + + +All rights reserved. + +Redistribution and use of this software in source and binary forms, +with or without modification, are permitted provided that the +following conditions are met: + +* Redistributions of source code must retain the above + copyright notice, this list of conditions and the + following disclaimer. + +* Redistributions in binary form must reproduce the above + copyright notice, this list of conditions and the + following disclaimer in the documentation and/or other + materials provided with the distribution. + +* Neither the name of the assimp team, nor the names of its + contributors may be used to endorse or promote products + derived from this software without specific prior + written permission of the assimp team. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +---------------------------------------------------------------------- +*/ + +/** @file BlenderTessellator.cpp + * @brief A simple tessellation wrapper + */ + + +#ifndef ASSIMP_BUILD_NO_BLEND_IMPORTER + +#include "BlenderDNA.h" +#include "BlenderScene.h" +#include "BlenderBMesh.h" +#include "BlenderTessellator.h" + +#include <stddef.h> + +static const unsigned int BLEND_TESS_MAGIC = 0x83ed9ac3; + +#if ASSIMP_BLEND_WITH_GLU_TESSELLATE + +namspace Assimp +{ + template< > const char* LogFunctions< BlenderTessellatorGL >::Prefix() + { + static auto prefix = "BLEND_TESS_GL: "; + return prefix; + } +} + +using namespace Assimp; +using namespace Assimp::Blender; + +#ifndef CALLBACK +#define CALLBACK +#endif + +// ------------------------------------------------------------------------------------------------ +BlenderTessellatorGL::BlenderTessellatorGL( BlenderBMeshConverter& converter ): + converter( &converter ) +{ +} + +// ------------------------------------------------------------------------------------------------ +BlenderTessellatorGL::~BlenderTessellatorGL( ) +{ +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorGL::Tessellate( const MLoop* polyLoop, int vertexCount, const std::vector< MVert >& vertices ) +{ + AssertVertexCount( vertexCount ); + + std::vector< VertexGL > polyLoopGL; + GenerateLoopVerts( polyLoopGL, polyLoop, vertexCount, vertices ); + + TessDataGL tessData; + Tesssellate( polyLoopGL, tessData ); + + TriangulateDrawCalls( tessData ); +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorGL::AssertVertexCount( int vertexCount ) +{ + if ( vertexCount <= 4 ) + { + ThrowException( "Expected more than 4 vertices for tessellation" ); + } +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorGL::GenerateLoopVerts( std::vector< VertexGL >& polyLoopGL, const MLoop* polyLoop, int vertexCount, const std::vector< MVert >& vertices ) +{ + for ( int i = 0; i < vertexCount; ++i ) + { + const MLoop& loopItem = polyLoop[ i ]; + const MVert& vertex = vertices[ loopItem.v ]; + polyLoopGL.push_back( VertexGL( vertex.co[ 0 ], vertex.co[ 1 ], vertex.co[ 2 ], loopItem.v, BLEND_TESS_MAGIC ) ); + } +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorGL::Tesssellate( std::vector< VertexGL >& polyLoopGL, TessDataGL& tessData ) +{ + GLUtesselator* tessellator = gluNewTess( ); + gluTessCallback( tessellator, GLU_TESS_BEGIN_DATA, reinterpret_cast< void ( CALLBACK * )( ) >( TessellateBegin ) ); + gluTessCallback( tessellator, GLU_TESS_END_DATA, reinterpret_cast< void ( CALLBACK * )( ) >( TessellateEnd ) ); + gluTessCallback( tessellator, GLU_TESS_VERTEX_DATA, reinterpret_cast< void ( CALLBACK * )( ) >( TessellateVertex ) ); + gluTessCallback( tessellator, GLU_TESS_COMBINE_DATA, reinterpret_cast< void ( CALLBACK * )( ) >( TessellateCombine ) ); + gluTessCallback( tessellator, GLU_TESS_EDGE_FLAG_DATA, reinterpret_cast< void ( CALLBACK * )( ) >( TessellateEdgeFlag ) ); + gluTessCallback( tessellator, GLU_TESS_ERROR_DATA, reinterpret_cast< void ( CALLBACK * )( ) >( TessellateError ) ); + gluTessProperty( tessellator, GLU_TESS_WINDING_RULE, GLU_TESS_WINDING_NONZERO ); + + gluTessBeginPolygon( tessellator, &tessData ); + gluTessBeginContour( tessellator ); + + for ( unsigned int i = 0; i < polyLoopGL.size( ); ++i ) + { + gluTessVertex( tessellator, reinterpret_cast< GLdouble* >( &polyLoopGL[ i ] ), &polyLoopGL[ i ] ); + } + + gluTessEndContour( tessellator ); + gluTessEndPolygon( tessellator ); +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorGL::TriangulateDrawCalls( const TessDataGL& tessData ) +{ + // NOTE - Because we are supplying a callback to GLU_TESS_EDGE_FLAG_DATA we don't technically + // need support for GL_TRIANGLE_STRIP and GL_TRIANGLE_FAN but we'll keep it here in case + // GLU tessellate changes or tri-strips and fans are wanted. + // See: http://www.opengl.org/sdk/docs/man2/xhtml/gluTessCallback.xml + for ( unsigned int i = 0; i < tessData.drawCalls.size( ); ++i ) + { + const DrawCallGL& drawCallGL = tessData.drawCalls[ i ]; + const VertexGL* vertices = &tessData.vertices[ drawCallGL.baseVertex ]; + if ( drawCallGL.drawMode == GL_TRIANGLES ) + { + MakeFacesFromTris( vertices, drawCallGL.vertexCount ); + } + else if ( drawCallGL.drawMode == GL_TRIANGLE_STRIP ) + { + MakeFacesFromTriStrip( vertices, drawCallGL.vertexCount ); + } + else if ( drawCallGL.drawMode == GL_TRIANGLE_FAN ) + { + MakeFacesFromTriFan( vertices, drawCallGL.vertexCount ); + } + } +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorGL::MakeFacesFromTris( const VertexGL* vertices, int vertexCount ) +{ + const int triangleCount = vertexCount / 3; + for ( int i = 0; i < triangleCount; ++i ) + { + int vertexBase = i * 3; + converter->AddFace( vertices[ vertexBase + 0 ].index, vertices[ vertexBase + 1 ].index, vertices[ vertexBase + 2 ].index ); + } +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorGL::MakeFacesFromTriStrip( const VertexGL* vertices, int vertexCount ) +{ + const int triangleCount = vertexCount - 2; + for ( int i = 0; i < triangleCount; ++i ) + { + int vertexBase = i; + converter->AddFace( vertices[ vertexBase + 0 ].index, vertices[ vertexBase + 1 ].index, vertices[ vertexBase + 2 ].index ); + } +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorGL::MakeFacesFromTriFan( const VertexGL* vertices, int vertexCount ) +{ + const int triangleCount = vertexCount - 2; + for ( int i = 0; i < triangleCount; ++i ) + { + int vertexBase = i; + converter->AddFace( vertices[ 0 ].index, vertices[ vertexBase + 1 ].index, vertices[ vertexBase + 2 ].index ); + } +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorGL::TessellateBegin( GLenum drawModeGL, void* userData ) +{ + TessDataGL& tessData = *reinterpret_cast< TessDataGL* >( userData ); + tessData.drawCalls.push_back( DrawCallGL( drawModeGL, tessData.vertices.size( ) ) ); +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorGL::TessellateEnd( void* ) +{ + // Do nothing +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorGL::TessellateVertex( const void* vtxData, void* userData ) +{ + TessDataGL& tessData = *reinterpret_cast< TessDataGL* >( userData ); + + const VertexGL& vertex = *reinterpret_cast< const VertexGL* >( vtxData ); + if ( vertex.magic != BLEND_TESS_MAGIC ) + { + ThrowException( "Point returned by GLU Tessellate was probably not one of ours. This indicates we need a new way to store vertex information" ); + } + tessData.vertices.push_back( vertex ); + if ( tessData.drawCalls.size( ) == 0 ) + { + ThrowException( "\"Vertex\" callback received before \"Begin\"" ); + } + ++( tessData.drawCalls.back( ).vertexCount ); +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorGL::TessellateCombine( const GLdouble intersection[ 3 ], const GLdouble* [ 4 ], const GLfloat [ 4 ], GLdouble** out, void* userData ) +{ + ThrowException( "Intersected polygon loops are not yet supported" ); +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorGL::TessellateEdgeFlag( GLboolean, void* ) +{ + // Do nothing +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorGL::TessellateError( GLenum errorCode, void* ) +{ + ThrowException( reinterpret_cast< const char* >( gluErrorString( errorCode ) ) ); +} + +#endif // ASSIMP_BLEND_WITH_GLU_TESSELLATE + +#if ASSIMP_BLEND_WITH_POLY_2_TRI + +namespace Assimp +{ + template< > const char* LogFunctions< BlenderTessellatorP2T >::Prefix() + { + static auto prefix = "BLEND_TESS_P2T: "; + return prefix; + } +} + +using namespace Assimp; +using namespace Assimp::Blender; + +// ------------------------------------------------------------------------------------------------ +BlenderTessellatorP2T::BlenderTessellatorP2T( BlenderBMeshConverter& converter ): + converter( &converter ) +{ +} + +// ------------------------------------------------------------------------------------------------ +BlenderTessellatorP2T::~BlenderTessellatorP2T( ) +{ +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorP2T::Tessellate( const MLoop* polyLoop, int vertexCount, const std::vector< MVert >& vertices ) +{ + AssertVertexCount( vertexCount ); + + // NOTE - We have to hope that points in a Blender polygon are roughly on the same plane. + // There may be some triangulation artifacts if they are wildly different. + + std::vector< PointP2T > points; + Copy3DVertices( polyLoop, vertexCount, vertices, points ); + + PlaneP2T plane = FindLLSQPlane( points ); + + aiMatrix4x4 transform = GeneratePointTransformMatrix( plane ); + + TransformAndFlattenVectices( transform, points ); + + std::vector< p2t::Point* > pointRefs; + ReferencePoints( points, pointRefs ); + + p2t::CDT cdt( pointRefs ); + + cdt.Triangulate( ); + std::vector< p2t::Triangle* > triangles = cdt.GetTriangles( ); + + MakeFacesFromTriangles( triangles ); +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorP2T::AssertVertexCount( int vertexCount ) +{ + if ( vertexCount <= 4 ) + { + ThrowException( "Expected more than 4 vertices for tessellation" ); + } +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorP2T::Copy3DVertices( const MLoop* polyLoop, int vertexCount, const std::vector< MVert >& vertices, std::vector< PointP2T >& points ) const +{ + points.resize( vertexCount ); + for ( int i = 0; i < vertexCount; ++i ) + { + const MLoop& loop = polyLoop[ i ]; + const MVert& vert = vertices[ loop.v ]; + + PointP2T& point = points[ i ]; + point.point3D.Set( vert.co[ 0 ], vert.co[ 1 ], vert.co[ 2 ] ); + point.index = loop.v; + point.magic = BLEND_TESS_MAGIC; + } +} + +// ------------------------------------------------------------------------------------------------ +aiMatrix4x4 BlenderTessellatorP2T::GeneratePointTransformMatrix( const Blender::PlaneP2T& plane ) const +{ + aiVector3D sideA( 1.0f, 0.0f, 0.0f ); + if ( std::fabs( plane.normal * sideA ) > 0.999f ) + { + sideA = aiVector3D( 0.0f, 1.0f, 0.0f ); + } + + aiVector3D sideB( plane.normal ^ sideA ); + sideB.Normalize( ); + sideA = sideB ^ plane.normal; + + aiMatrix4x4 result; + result.a1 = sideA.x; + result.a2 = sideA.y; + result.a3 = sideA.z; + result.b1 = sideB.x; + result.b2 = sideB.y; + result.b3 = sideB.z; + result.c1 = plane.normal.x; + result.c2 = plane.normal.y; + result.c3 = plane.normal.z; + result.a4 = plane.centre.x; + result.b4 = plane.centre.y; + result.c4 = plane.centre.z; + result.Inverse( ); + + return result; +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorP2T::TransformAndFlattenVectices( const aiMatrix4x4& transform, std::vector< Blender::PointP2T >& vertices ) const +{ + for ( size_t i = 0; i < vertices.size( ); ++i ) + { + PointP2T& point = vertices[ i ]; + point.point3D = transform * point.point3D; + point.point2D.set( point.point3D.y, point.point3D.z ); + } +} + +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorP2T::ReferencePoints( std::vector< Blender::PointP2T >& points, std::vector< p2t::Point* >& pointRefs ) const +{ + pointRefs.resize( points.size( ) ); + for ( size_t i = 0; i < points.size( ); ++i ) + { + pointRefs[ i ] = &points[ i ].point2D; + } +} + +// ------------------------------------------------------------------------------------------------ +inline PointP2T& BlenderTessellatorP2T::GetActualPointStructure( p2t::Point& point ) const +{ +#if defined __clang__ +# pragma clang diagnostic push +# pragma clang diagnostic ignored "-Winvalid-offsetof" +#endif // __clang__ + unsigned int pointOffset = offsetof( PointP2T, point2D ); +#if defined __clang__ +# pragma clang diagnostic pop +#endif + PointP2T& pointStruct = *reinterpret_cast< PointP2T* >( reinterpret_cast< char* >( &point ) - pointOffset ); + if ( pointStruct.magic != static_cast<int>( BLEND_TESS_MAGIC ) ) + { + ThrowException( "Point returned by poly2tri was probably not one of ours. This indicates we need a new way to store vertex information" ); + } + return pointStruct; +} +// ------------------------------------------------------------------------------------------------ +void BlenderTessellatorP2T::MakeFacesFromTriangles( std::vector< p2t::Triangle* >& triangles ) const +{ + for ( size_t i = 0; i < triangles.size( ); ++i ) + { + p2t::Triangle& Triangle = *triangles[ i ]; + + PointP2T& pointA = GetActualPointStructure( *Triangle.GetPoint( 0 ) ); + PointP2T& pointB = GetActualPointStructure( *Triangle.GetPoint( 1 ) ); + PointP2T& pointC = GetActualPointStructure( *Triangle.GetPoint( 2 ) ); + + converter->AddFace( pointA.index, pointB.index, pointC.index ); + } +} + +// ------------------------------------------------------------------------------------------------ +inline float p2tMax( float a, float b ) +{ + return a > b ? a : b; +} + +// ------------------------------------------------------------------------------------------------ +// Adapted from: http://missingbytes.blogspot.co.uk/2012/06/fitting-plane-to-point-cloud.html +float BlenderTessellatorP2T::FindLargestMatrixElem( const aiMatrix3x3& mtx ) const +{ + float result = 0.0f; + + for ( unsigned int x = 0; x < 3; ++x ) + { + for ( unsigned int y = 0; y < 3; ++y ) + { + result = p2tMax( std::fabs( mtx[ x ][ y ] ), result ); + } + } + + return result; +} + +// ------------------------------------------------------------------------------------------------ +// Apparently Assimp doesn't have matrix scaling +aiMatrix3x3 BlenderTessellatorP2T::ScaleMatrix( const aiMatrix3x3& mtx, float scale ) const +{ + aiMatrix3x3 result; + + for ( unsigned int x = 0; x < 3; ++x ) + { + for ( unsigned int y = 0; y < 3; ++y ) + { + result[ x ][ y ] = mtx[ x ][ y ] * scale; + } + } + + return result; +} + + +// ------------------------------------------------------------------------------------------------ +// Adapted from: http://missingbytes.blogspot.co.uk/2012/06/fitting-plane-to-point-cloud.html +aiVector3D BlenderTessellatorP2T::GetEigenVectorFromLargestEigenValue( const aiMatrix3x3& mtx ) const +{ + const float scale = FindLargestMatrixElem( mtx ); + aiMatrix3x3 mc = ScaleMatrix( mtx, 1.0f / scale ); + mc = mc * mc * mc; + + aiVector3D v( 1.0f ); + aiVector3D lastV = v; + for ( int i = 0; i < 100; ++i ) + { + v = mc * v; + v.Normalize( ); + if ( ( v - lastV ).SquareLength( ) < 1e-16f ) + { + break; + } + lastV = v; + } + return v; +} + +// ------------------------------------------------------------------------------------------------ +// Adapted from: http://missingbytes.blogspot.co.uk/2012/06/fitting-plane-to-point-cloud.html +PlaneP2T BlenderTessellatorP2T::FindLLSQPlane( const std::vector< PointP2T >& points ) const +{ + PlaneP2T result; + + aiVector3D sum( 0.0 ); + for ( size_t i = 0; i < points.size( ); ++i ) + { + sum += points[ i ].point3D; + } + result.centre = sum * (ai_real)( 1.0 / points.size( ) ); + + ai_real sumXX = 0.0; + ai_real sumXY = 0.0; + ai_real sumXZ = 0.0; + ai_real sumYY = 0.0; + ai_real sumYZ = 0.0; + ai_real sumZZ = 0.0; + for ( size_t i = 0; i < points.size( ); ++i ) + { + aiVector3D offset = points[ i ].point3D - result.centre; + sumXX += offset.x * offset.x; + sumXY += offset.x * offset.y; + sumXZ += offset.x * offset.z; + sumYY += offset.y * offset.y; + sumYZ += offset.y * offset.z; + sumZZ += offset.z * offset.z; + } + + aiMatrix3x3 mtx( sumXX, sumXY, sumXZ, sumXY, sumYY, sumYZ, sumXZ, sumYZ, sumZZ ); + + const ai_real det = mtx.Determinant( ); + if ( det == 0.0f ) + { + result.normal = aiVector3D( 0.0f ); + } + else + { + aiMatrix3x3 invMtx = mtx; + invMtx.Inverse( ); + result.normal = GetEigenVectorFromLargestEigenValue( invMtx ); + } + + return result; +} + +#endif // ASSIMP_BLEND_WITH_POLY_2_TRI + +#endif // ASSIMP_BUILD_NO_BLEND_IMPORTER |