1 /*
2 Open Asset Import Library (assimp)
3 ----------------------------------------------------------------------
4 
5 Copyright (c) 2006-2021, assimp team
6 
7 
8 All rights reserved.
9 
10 Redistribution and use of this software in source and binary forms,
11 with or without modification, are permitted provided that the
12 following conditions are met:
13 
14 * Redistributions of source code must retain the above
15   copyright notice, this list of conditions and the
16   following disclaimer.
17 
18 * Redistributions in binary form must reproduce the above
19   copyright notice, this list of conditions and the
20   following disclaimer in the documentation and/or other
21   materials provided with the distribution.
22 
23 * Neither the name of the assimp team, nor the names of its
24   contributors may be used to endorse or promote products
25   derived from this software without specific prior
26   written permission of the assimp team.
27 
28 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
31 A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
32 OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
33 SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34 LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36 THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
38 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
39 
40 ----------------------------------------------------------------------
41 */
42 
43 /** Defines a post processing step to limit the number of bones affecting a single vertex. */
44 #ifndef AI_LIMITBONEWEIGHTSPROCESS_H_INC
45 #define AI_LIMITBONEWEIGHTSPROCESS_H_INC
46 
47 #include "Common/BaseProcess.h"
48 
49 // Forward declarations
50 struct aiMesh;
51 
52 class LimitBoneWeightsTest;
53 
54 namespace Assimp {
55 
56 // NOTE: If you change these limits, don't forget to change the
57 // corresponding values in all Assimp ports
58 
59 // **********************************************************
60 // Java: ConfigProperty.java,
61 //  ConfigProperty.DEFAULT_BONE_WEIGHT_LIMIT
62 // **********************************************************
63 
64 #if (!defined AI_LMW_MAX_WEIGHTS)
65 #   define AI_LMW_MAX_WEIGHTS   0x4
66 #endif // !! AI_LMW_MAX_WEIGHTS
67 
68 // ---------------------------------------------------------------------------
69 /** This post processing step limits the number of bones affecting a vertex
70 * to a certain maximum value. If a vertex is affected by more than that number
71 * of bones, the bone weight with the least influence on this vertex are removed.
72 * The other weights on this bone are then renormalized to assure the sum weight
73 * to be 1.
74 */
75 class ASSIMP_API LimitBoneWeightsProcess : public BaseProcess {
76 public:
77     LimitBoneWeightsProcess();
78     ~LimitBoneWeightsProcess();
79 
80     // -------------------------------------------------------------------
81     /** Returns whether the processing step is present in the given flag.
82     * @param pFlags The processing flags the importer was called with.
83     *   A bitwise combination of #aiPostProcessSteps.
84     * @return true if the process is present in this flag fields,
85     *   false if not.
86     */
87     bool IsActive( unsigned int pFlags) const;
88 
89     // -------------------------------------------------------------------
90     /** Called prior to ExecuteOnScene().
91     * The function is a request to the process to update its configuration
92     * basing on the Importer's configuration property list.
93     */
94     void SetupProperties(const Importer* pImp);
95 
96     // -------------------------------------------------------------------
97     /** Limits the bone weight count for all vertices in the given mesh.
98     * @param pMesh The mesh to process.
99     */
100     void ProcessMesh( aiMesh* pMesh);
101 
102     // -------------------------------------------------------------------
103     /** Executes the post processing step on the given imported data.
104     * At the moment a process is not supposed to fail.
105     * @param pScene The imported data to work at.
106     */
107     void Execute( aiScene* pScene);
108 
109     // -------------------------------------------------------------------
110     /** Describes a bone weight on a vertex */
111     struct Weight {
112         unsigned int mBone; ///< Index of the bone
113         float mWeight;      ///< Weight of that bone on this vertex
WeightWeight114         Weight() AI_NO_EXCEPT
115         : mBone(0)
116         , mWeight(0.0f) {
117             // empty
118         }
119 
WeightWeight120         Weight( unsigned int pBone, float pWeight)
121         : mBone(pBone)
122         , mWeight(pWeight) {
123             // empty
124         }
125 
126         /** Comparison operator to sort bone weights by descending weight */
127         bool operator < (const Weight& pWeight) const {
128             return mWeight > pWeight.mWeight;
129         }
130     };
131 
132     /** Maximum number of bones influencing any single vertex. */
133     unsigned int mMaxWeights;
134 };
135 
136 } // end of namespace Assimp
137 
138 #endif // AI_LIMITBONEWEIGHTSPROCESS_H_INC
139