added DropFaceNormals process

code/DropFaceNormalsProcess.cpp

@@ -0,0 +1,108 @@
+/*
+---------------------------------------------------------------------------
+Open Asset Import Library (assimp)
+---------------------------------------------------------------------------
+
+Copyright (c) 2006-2018, 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 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()
+{
+    // nothing to do here
+}
+
+// ------------------------------------------------------------------------------------------------
+// Destructor, private as well
+DropFaceNormalsProcess::~DropFaceNormalsProcess()
+{
+    // nothing to do here
+}
+
+// ------------------------------------------------------------------------------------------------
+// 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::GenMeshFaceNormals (aiMesh* pMesh) {
+    if (NULL == pMesh->mNormals) {
+        return false;
+    }
+    
+    delete[] pMesh->mNormals;
+    return true;
+}

code/DropFaceNormalsProcess.h

@@ -0,0 +1,86 @@
+/*
+Open Asset Import Library (assimp)
+----------------------------------------------------------------------
+
+Copyright (c) 2006-2018, 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 Defines a post processing step to compute face normals for all loaded faces*/
+#ifndef AI_DROPFACENORMALPROCESS_H_INC
+#define AI_DROPFACENORMALPROCESS_H_INC
+
+#include "BaseProcess.h"
+#include <assimp/mesh.h>
+
+namespace Assimp
+{
+
+// ---------------------------------------------------------------------------
+/** The DropFaceNormalsProcess computes face normals for all faces of all meshes
+*/
+class ASSIMP_API_WINONLY DropFaceNormalsProcess : public BaseProcess
+{
+public:
+
+    DropFaceNormalsProcess();
+    ~DropFaceNormalsProcess();
+
+public:
+    // -------------------------------------------------------------------
+    /** Returns whether the processing step is present in the given flag field.
+    * @param pFlags The processing flags the importer was called with. A bitwise
+    *   combination of #aiPostProcessSteps.
+    * @return true if the process is present in this flag fields, false if not.
+    */
+    bool IsActive( unsigned int pFlags) const;
+
+    // -------------------------------------------------------------------
+    /** Executes the post processing step on the given imported data.
+    * At the moment a process is not supposed to fail.
+    * @param pScene The imported data to work at.
+    */
+    void Execute( aiScene* pScene);
+
+
+private:
+    bool DropMeshFaceNormals(aiMesh* pcMesh);
+};
+
+} // end of namespace Assimp
+
+#endif // !!AI_DROPFACENORMALPROCESS_H_INC

include/assimp/postprocess.h

@@ -562,6 +562,18 @@ enum aiPostProcessSteps
 
 
     aiProcess_ForceGenNormals = 0x20000000,
+
+    // -------------------------------------------------------------------------
+    /** <hr>Drops normals for all faces of all meshes.
+     *
+     * This is ignored if no normals are present.
+     * Face normals are shared between all points of a single face,
+     * so a single point can have multiple normals, which
+     * forces the library to duplicate vertices in some cases.
+     * #aiProcess_JoinIdenticalVertices is *senseless* then.
+     * This process gives sense back to aiProcess_JoinIdenticalVertices
+     */
+    aiProcess_DropNormals = 0x40000000,
 };
 
 

tools/assimp_cmd/Main.cpp

@@ -397,6 +397,9 @@ int ProcessStandardArguments(
 		else if (! strcmp( param, "-gsn") || ! strcmp( param, "--gen-smooth-normals")) {
 			fill.ppFlags |= aiProcess_GenSmoothNormals;
 		}
+    else if (! strcmp( param, "-dn") || ! strcmp( param, "--drop-normals")) {
+			fill.ppFlags |= aiProcess_DropNormals;
+		}
 		else if (! strcmp( param, "-gn") || ! strcmp( param, "--gen-normals")) {
 			fill.ppFlags |= aiProcess_GenNormals;
 		}