assimp.assimp/code/PostProcessing/DropFaceNormalsProcess.cpp

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

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

using namespace Assimp;

// ------------------------------------------------------------------------------------------------
// 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;
}