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*/

/** @file Implementation of the post processing step to drop face
* normals for all imported faces.
*/


#include "DropFaceNormalsProcess.h"
#include <assimp/postprocess.h>
#include <assimp/scene.h>
#include <assimp/DefaultLogger.hpp>
#include <assimp/Exceptional.h>

using namespace Assimp;

// ------------------------------------------------------------------------------------------------
// Constructor to be privately used by Importer
DropFaceNormalsProcess::DropFaceNormalsProcess() = default;

// ------------------------------------------------------------------------------------------------
// Destructor, private as well
DropFaceNormalsProcess::~DropFaceNormalsProcess() = default;

// ------------------------------------------------------------------------------------------------
// Returns whether the processing step is present in the given flag field.
bool DropFaceNormalsProcess::IsActive( unsigned int pFlags) const {
 return (pFlags & aiProcess_DropNormals) != 0;
}

// ------------------------------------------------------------------------------------------------
// Executes the post processing step on the given imported data.
void DropFaceNormalsProcess::Execute( aiScene* pScene) {
 ASSIMP_LOG_DEBUG("DropFaceNormalsProcess begin");

 if (pScene->mFlags & AI_SCENE_FLAGS_NON_VERBOSE_FORMAT) {
 throw DeadlyImportError("Post-processing order mismatch: expecting pseudo-indexed (\"verbose\") vertices here");
 }

 bool bHas = false;
 for( unsigned int a = 0; a < pScene->mNumMeshes; a++) {
 bHas |= this->DropMeshFaceNormals( pScene->mMeshes[a]);
 }
 if (bHas) {
 ASSIMP_LOG_INFO("DropFaceNormalsProcess finished. "
 "Face normals have been removed");
 } else {
 ASSIMP_LOG_DEBUG("DropFaceNormalsProcess finished. "
 "No normals were present");
 }
}

// ------------------------------------------------------------------------------------------------
// Executes the post processing step on the given imported data.
bool DropFaceNormalsProcess::DropMeshFaceNormals (aiMesh* mesh) {
 ai_assert(nullptr != mesh);

 if (nullptr == mesh->mNormals) {
 return false;
 }

 delete[] mesh->mNormals;
 mesh->mNormals = nullptr;
 return true;
}