nuclear@0: /*
nuclear@0: ---------------------------------------------------------------------------
nuclear@0: Open Asset Import Library (assimp)
nuclear@0: ---------------------------------------------------------------------------
nuclear@0: 
nuclear@0: Copyright (c) 2006-2012, assimp team
nuclear@0: 
nuclear@0: All rights reserved.
nuclear@0: 
nuclear@0: Redistribution and use of this software in source and binary forms, 
nuclear@0: with or without modification, are permitted provided that the following 
nuclear@0: conditions are met:
nuclear@0: 
nuclear@0: * Redistributions of source code must retain the above
nuclear@0:   copyright notice, this list of conditions and the
nuclear@0:   following disclaimer.
nuclear@0: 
nuclear@0: * Redistributions in binary form must reproduce the above
nuclear@0:   copyright notice, this list of conditions and the
nuclear@0:   following disclaimer in the documentation and/or other
nuclear@0:   materials provided with the distribution.
nuclear@0: 
nuclear@0: * Neither the name of the assimp team, nor the names of its
nuclear@0:   contributors may be used to endorse or promote products
nuclear@0:   derived from this software without specific prior
nuclear@0:   written permission of the assimp team.
nuclear@0: 
nuclear@0: THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
nuclear@0: "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
nuclear@0: LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
nuclear@0: A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 
nuclear@0: OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
nuclear@0: SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
nuclear@0: LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
nuclear@0: DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 
nuclear@0: THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
nuclear@0: (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
nuclear@0: OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
nuclear@0: ---------------------------------------------------------------------------
nuclear@0: */
nuclear@0: 
nuclear@0: /** @file Implementation of the post processing step to generate face
nuclear@0: * normals for all imported faces.
nuclear@0: */
nuclear@0: 
nuclear@0: #include "AssimpPCH.h"
nuclear@0: #include "GenFaceNormalsProcess.h"
nuclear@0: 
nuclear@0: 
nuclear@0: using namespace Assimp;
nuclear@0: 
nuclear@0: // ------------------------------------------------------------------------------------------------
nuclear@0: // Constructor to be privately used by Importer
nuclear@0: GenFaceNormalsProcess::GenFaceNormalsProcess()
nuclear@0: {
nuclear@0: 	// nothing to do here
nuclear@0: }
nuclear@0: 
nuclear@0: // ------------------------------------------------------------------------------------------------
nuclear@0: // Destructor, private as well
nuclear@0: GenFaceNormalsProcess::~GenFaceNormalsProcess()
nuclear@0: {
nuclear@0: 	// nothing to do here
nuclear@0: }
nuclear@0: 
nuclear@0: // ------------------------------------------------------------------------------------------------
nuclear@0: // Returns whether the processing step is present in the given flag field.
nuclear@0: bool GenFaceNormalsProcess::IsActive( unsigned int pFlags) const
nuclear@0: {
nuclear@0: 	return	(pFlags & aiProcess_GenNormals) != 0;
nuclear@0: }
nuclear@0: 
nuclear@0: // ------------------------------------------------------------------------------------------------
nuclear@0: // Executes the post processing step on the given imported data.
nuclear@0: void GenFaceNormalsProcess::Execute( aiScene* pScene)
nuclear@0: {
nuclear@0: 	DefaultLogger::get()->debug("GenFaceNormalsProcess begin");
nuclear@0: 
nuclear@0: 	if (pScene->mFlags & AI_SCENE_FLAGS_NON_VERBOSE_FORMAT) {
nuclear@0: 		throw DeadlyImportError("Post-processing order mismatch: expecting pseudo-indexed (\"verbose\") vertices here");
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	bool bHas = false;
nuclear@0: 	for( unsigned int a = 0; a < pScene->mNumMeshes; a++)	{
nuclear@0: 		if(this->GenMeshFaceNormals( pScene->mMeshes[a])) {
nuclear@0: 			bHas = true;
nuclear@0: 		}
nuclear@0: 	}
nuclear@0: 	if (bHas)	{
nuclear@0: 		DefaultLogger::get()->info("GenFaceNormalsProcess finished. "
nuclear@0: 			"Face normals have been calculated");
nuclear@0: 	}
nuclear@0: 	else DefaultLogger::get()->debug("GenFaceNormalsProcess finished. "
nuclear@0: 		"Normals are already there");
nuclear@0: }
nuclear@0: 
nuclear@0: // ------------------------------------------------------------------------------------------------
nuclear@0: // Executes the post processing step on the given imported data.
nuclear@0: bool GenFaceNormalsProcess::GenMeshFaceNormals (aiMesh* pMesh)
nuclear@0: {
nuclear@0: 	if (NULL != pMesh->mNormals) {
nuclear@0: 		return false;
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	// If the mesh consists of lines and/or points but not of
nuclear@0: 	// triangles or higher-order polygons the normal vectors
nuclear@0: 	// are undefined.
nuclear@0: 	if (!(pMesh->mPrimitiveTypes & (aiPrimitiveType_TRIANGLE | aiPrimitiveType_POLYGON)))	{
nuclear@0: 		DefaultLogger::get()->info("Normal vectors are undefined for line and point meshes");
nuclear@0: 		return false;
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	// allocate an array to hold the output normals
nuclear@0: 	pMesh->mNormals = new aiVector3D[pMesh->mNumVertices];
nuclear@0: 	const float qnan = get_qnan();
nuclear@0: 
nuclear@0: 	// iterate through all faces and compute per-face normals but store them per-vertex. 
nuclear@0: 	for( unsigned int a = 0; a < pMesh->mNumFaces; a++)	{
nuclear@0: 		const aiFace& face = pMesh->mFaces[a];
nuclear@0: 		if (face.mNumIndices < 3)	{
nuclear@0: 			// either a point or a line -> no well-defined normal vector
nuclear@0: 			for (unsigned int i = 0;i < face.mNumIndices;++i) {
nuclear@0: 				pMesh->mNormals[face.mIndices[i]] = aiVector3D(qnan);
nuclear@0: 			}
nuclear@0: 			continue;
nuclear@0: 		}
nuclear@0: 
nuclear@0: 		const aiVector3D* pV1 = &pMesh->mVertices[face.mIndices[0]];
nuclear@0: 		const aiVector3D* pV2 = &pMesh->mVertices[face.mIndices[1]];
nuclear@0: 		const aiVector3D* pV3 = &pMesh->mVertices[face.mIndices[face.mNumIndices-1]];
nuclear@0: 		const aiVector3D vNor = ((*pV2 - *pV1) ^ (*pV3 - *pV1)).Normalize();
nuclear@0: 
nuclear@0: 		for (unsigned int i = 0;i < face.mNumIndices;++i) {
nuclear@0: 			pMesh->mNormals[face.mIndices[i]] = vNor;
nuclear@0: 		}
nuclear@0: 	}
nuclear@0: 	return true;
nuclear@0: }