Add Assimp library in thirdparty

From https://github.com/assimp/assimp repo at d2b45377e4b09a1f43be95e45553afcc06b03f4b

1 files changed, 146 insertions, 0 deletions

diff --git a/thirdparty/assimp/code/GenFaceNormalsProcess.cpp b/thirdparty/assimp/code/GenFaceNormalsProcess.cpp
new file mode 100644
index 0000000000..028334dec7
--- /dev/null
+++ b/thirdparty/assimp/code/GenFaceNormalsProcess.cpp
@@ -0,0 +1,146 @@
+/*
+---------------------------------------------------------------------------
+Open Asset Import Library (assimp)
+---------------------------------------------------------------------------
+
+Copyright (c) 2006-2019, 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 generate face
+* normals for all imported faces.
+*/
+
+
+#include "GenFaceNormalsProcess.h"
+#include <assimp/postprocess.h>
+#include <assimp/scene.h>
+#include <assimp/DefaultLogger.hpp>
+#include <assimp/Exceptional.h>
+#include <assimp/qnan.h>
+
+
+using namespace Assimp;
+
+// ------------------------------------------------------------------------------------------------
+// Constructor to be privately used by Importer
+GenFaceNormalsProcess::GenFaceNormalsProcess()
+{
+    // nothing to do here
+}
+
+// ------------------------------------------------------------------------------------------------
+// Destructor, private as well
+GenFaceNormalsProcess::~GenFaceNormalsProcess()
+{
+    // nothing to do here
+}
+
+// ------------------------------------------------------------------------------------------------
+// Returns whether the processing step is present in the given flag field.
+bool GenFaceNormalsProcess::IsActive( unsigned int pFlags) const {
+    force_ = (pFlags & aiProcess_ForceGenNormals) != 0;
+    return  (pFlags & aiProcess_GenNormals) != 0;
+}
+
+// ------------------------------------------------------------------------------------------------
+// Executes the post processing step on the given imported data.
+void GenFaceNormalsProcess::Execute( aiScene* pScene) {
+    ASSIMP_LOG_DEBUG("GenFaceNormalsProcess 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++)   {
+        if(this->GenMeshFaceNormals( pScene->mMeshes[a])) {
+            bHas = true;
+        }
+    }
+    if (bHas)   {
+        ASSIMP_LOG_INFO("GenFaceNormalsProcess finished. "
+            "Face normals have been calculated");
+    } else {
+        ASSIMP_LOG_DEBUG("GenFaceNormalsProcess finished. "
+            "Normals are already there");
+    }
+}
+
+// ------------------------------------------------------------------------------------------------
+// Executes the post processing step on the given imported data.
+bool GenFaceNormalsProcess::GenMeshFaceNormals (aiMesh* pMesh)
+{
+    if (NULL != pMesh->mNormals) {
+        if (force_) delete[] pMesh->mNormals;
+        else return false;
+    }
+
+    // If the mesh consists of lines and/or points but not of
+    // triangles or higher-order polygons the normal vectors
+    // are undefined.
+    if (!(pMesh->mPrimitiveTypes & (aiPrimitiveType_TRIANGLE | aiPrimitiveType_POLYGON)))   {
+        ASSIMP_LOG_INFO("Normal vectors are undefined for line and point meshes");
+        return false;
+    }
+
+    // allocate an array to hold the output normals
+    pMesh->mNormals = new aiVector3D[pMesh->mNumVertices];
+    const float qnan = get_qnan();
+
+    // iterate through all faces and compute per-face normals but store them per-vertex.
+    for( unsigned int a = 0; a < pMesh->mNumFaces; a++) {
+        const aiFace& face = pMesh->mFaces[a];
+        if (face.mNumIndices < 3)   {
+            // either a point or a line -> no well-defined normal vector
+            for (unsigned int i = 0;i < face.mNumIndices;++i) {
+                pMesh->mNormals[face.mIndices[i]] = aiVector3D(qnan);
+            }
+            continue;
+        }
+
+        const aiVector3D* pV1 = &pMesh->mVertices[face.mIndices[0]];
+        const aiVector3D* pV2 = &pMesh->mVertices[face.mIndices[1]];
+        const aiVector3D* pV3 = &pMesh->mVertices[face.mIndices[face.mNumIndices-1]];
+        const aiVector3D vNor = ((*pV2 - *pV1) ^ (*pV3 - *pV1)).NormalizeSafe();
+
+        for (unsigned int i = 0;i < face.mNumIndices;++i) {
+            pMesh->mNormals[face.mIndices[i]] = vNor;
+        }
+    }
+    return true;
+}