add assimp submodule

1 files changed, 190 insertions, 0 deletions

diff --git a/src/mesh/assimp-master/include/assimp/SpatialSort.h b/src/mesh/assimp-master/include/assimp/SpatialSort.h
new file mode 100644
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+++ b/src/mesh/assimp-master/include/assimp/SpatialSort.h
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+/*
+Open Asset Import Library (assimp)
+----------------------------------------------------------------------
+
+Copyright (c) 2006-2022, 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.
+
+----------------------------------------------------------------------
+*/
+
+/** Small helper classes to optimise finding vertizes close to a given location */
+#pragma once
+#ifndef AI_SPATIALSORT_H_INC
+#define AI_SPATIALSORT_H_INC
+
+#ifdef __GNUC__
+#pragma GCC system_header
+#endif
+
+#include <assimp/types.h>
+#include <vector>
+#include <limits>
+
+namespace Assimp {
+
+// ------------------------------------------------------------------------------------------------
+/** A little helper class to quickly find all vertices in the epsilon environment of a given
+ * position. Construct an instance with an array of positions. The class stores the given positions
+ * by their indices and sorts them by their distance to an arbitrary chosen plane.
+ * You can then query the instance for all vertices close to a given position in an average O(log n)
+ * time, with O(n) worst case complexity when all vertices lay on the plane. The plane is chosen
+ * so that it avoids common planes in usual data sets. */
+// ------------------------------------------------------------------------------------------------
+class ASSIMP_API SpatialSort {
+public:
+    SpatialSort();
+
+    // ------------------------------------------------------------------------------------
+    /** Constructs a spatially sorted representation from the given position array.
+     * Supply the positions in its layout in memory, the class will only refer to them
+     * by index.
+     * @param pPositions Pointer to the first position vector of the array.
+     * @param pNumPositions Number of vectors to expect in that array.
+     * @param pElementOffset Offset in bytes from the beginning of one vector in memory
+     *   to the beginning of the next vector. */
+    SpatialSort(const aiVector3D *pPositions, unsigned int pNumPositions,
+            unsigned int pElementOffset);
+
+    /** Destructor */
+    ~SpatialSort();
+
+    // ------------------------------------------------------------------------------------
+    /** Sets the input data for the SpatialSort. This replaces existing data, if any.
+     *  The new data receives new indices in ascending order.
+     *
+     * @param pPositions Pointer to the first position vector of the array.
+     * @param pNumPositions Number of vectors to expect in that array.
+     * @param pElementOffset Offset in bytes from the beginning of one vector in memory
+     *   to the beginning of the next vector.
+     * @param pFinalize Specifies whether the SpatialSort's internal representation
+     *   is finalized after the new data has been added. Finalization is
+     *   required in order to use #FindPosition() or #GenerateMappingTable().
+     *   If you don't finalize yet, you can use #Append() to add data from
+     *   other sources.*/
+    void Fill(const aiVector3D *pPositions, unsigned int pNumPositions,
+            unsigned int pElementOffset,
+            bool pFinalize = true);
+
+    // ------------------------------------------------------------------------------------
+    /** Same as #Fill(), except the method appends to existing data in the #SpatialSort. */
+    void Append(const aiVector3D *pPositions, unsigned int pNumPositions,
+            unsigned int pElementOffset,
+            bool pFinalize = true);
+
+    // ------------------------------------------------------------------------------------
+    /** Finalize the spatial hash data structure. This can be useful after
+     *  multiple calls to #Append() with the pFinalize parameter set to false.
+     *  This is finally required before one of #FindPositions() and #GenerateMappingTable()
+     *  can be called to query the spatial sort.*/
+    void Finalize();
+
+    // ------------------------------------------------------------------------------------
+    /** Returns an iterator for all positions close to the given position.
+     * @param pPosition The position to look for vertices.
+     * @param pRadius Maximal distance from the position a vertex may have to be counted in.
+     * @param poResults The container to store the indices of the found positions.
+     *   Will be emptied by the call so it may contain anything.
+     * @return An iterator to iterate over all vertices in the given area.*/
+    void FindPositions(const aiVector3D &pPosition, ai_real pRadius,
+            std::vector<unsigned int> &poResults) const;
+
+    // ------------------------------------------------------------------------------------
+    /** Fills an array with indices of all positions identical to the given position. In
+     *  opposite to FindPositions(), not an epsilon is used but a (very low) tolerance of
+     *  four floating-point units.
+     * @param pPosition The position to look for vertices.
+     * @param poResults The container to store the indices of the found positions.
+     *   Will be emptied by the call so it may contain anything.*/
+    void FindIdenticalPositions(const aiVector3D &pPosition,
+            std::vector<unsigned int> &poResults) const;
+
+    // ------------------------------------------------------------------------------------
+    /** Compute a table that maps each vertex ID referring to a spatially close
+     *  enough position to the same output ID. Output IDs are assigned in ascending order
+     *  from 0...n.
+     * @param fill Will be filled with numPositions entries.
+     * @param pRadius Maximal distance from the position a vertex may have to
+     *   be counted in.
+     *  @return Number of unique vertices (n).  */
+    unsigned int GenerateMappingTable(std::vector<unsigned int> &fill,
+            ai_real pRadius) const;
+
+protected:
+    /** Return the distance to the sorting plane. */
+    ai_real CalculateDistance(const aiVector3D &pPosition) const;
+
+protected:
+    /** Normal of the sorting plane, normalized.
+     */
+    aiVector3D mPlaneNormal;
+
+    /** The centroid of the positions, which is used as a point on the sorting plane
+     * when calculating distance. This value is calculated in Finalize.
+    */
+    aiVector3D mCentroid;
+
+    /** An entry in a spatially sorted position array. Consists of a vertex index,
+     * its position and its pre-calculated distance from the reference plane */
+    struct Entry {
+        unsigned int mIndex; ///< The vertex referred by this entry
+        aiVector3D mPosition; ///< Position
+        /// Distance of this vertex to the sorting plane. This is set by Finalize.
+        ai_real mDistance; 
+
+        Entry() AI_NO_EXCEPT
+                : mIndex(std::numeric_limits<unsigned int>::max()),
+                  mPosition(),
+                  mDistance(std::numeric_limits<ai_real>::max()) {
+            // empty
+        }
+        Entry(unsigned int pIndex, const aiVector3D &pPosition) :
+                mIndex(pIndex), mPosition(pPosition), mDistance(std::numeric_limits<ai_real>::max()) {
+            // empty
+        }
+
+        bool operator<(const Entry &e) const { return mDistance < e.mDistance; }
+    };
+
+    // all positions, sorted by distance to the sorting plane
+    std::vector<Entry> mPositions;
+
+    /// false until the Finalize method is called.
+    bool mFinalized;
+};
+
+} // end of namespace Assimp
+
+#endif // AI_SPATIALSORT_H_INC