Commit c5e3e16a authored by Christopher Tenter's avatar Christopher Tenter
Browse files

initial MeshCompiler check-in

git-svn-id: 383ad7c9-94d9-4d36-a494-682f7c89f535
parent 58dd7d92
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#pragma once
#include "VertexDeclaration.hh"
#include <map>
#include <vector>
#include <stdio.h>
Mesh buffer assembler:
Builds a pair of vertex and index buffer based on a poly mesh.
- flexible processing pipeline
- uses index mapping only -> lower memory consumption
- independent of OpenMesh, OpenGL
1. Create a vertex declaration to specify your wanted
vertex format, such as float3 pos, float3 normal..
2. Set your vertex data.
Example in (float3 pos, float3 normal, float2 texc) format:
float VertexPositions[100*3] = {..};
float VertexNormals[120*3] = {..};
float VertexUV[80*2] = {..};
drawMesh->setVertices(100, VertexPositions, 12);
drawMesh->setNormals(120, VertexNormals, 12);
drawMesh->setTexCoords(80, VertexUV, 8);
Note that different indices for vertices, normals and texcoords are allowed,
hence the various element numbers 100, 120 and 80.
Example 2 (interleaved input)
float Vertices[100] = {
x0, y0, z0, u0, v0, nx0, ny0, nz0,
x1, y1, z1, u1, v1, nx1, ny1, nz1,
The stride is 8*4 = 32 bytes.
We use parameters as follows.
drawMesh->setVertices(100, Vertices, 32);
drawMesh->setNormals(100, (char*)Vertices + 20, 32);
drawMesh->setTexCoords(100, (char*)Vertices + 12, 32);
3. Set index data.
Two methods are supported for this.
You can either specify one index set for all vertex attributes
or use another index buffer for each vertex attribute.
The latter means having different indices for vertex and texcoords for example.
drawMesh->setNumFaces(32, 96);
for each face i
int* faceVertexIndices = {v0, v1, v2, ...};
setFaceVerts(i, 3, faceVertexIndices);
4. finish the initialization by calling the build() function
namespace ACG{
class MeshCompilerFaceInput
// face data input interface
// allows flexible and memory efficient face data input
virtual ~MeshCompilerFaceInput(){}
virtual int getNumFaces() = 0;
/** Get total number of indices in one attribute channel.
* i.e. total number of position indices of the whole mesh
virtual int getNumIndices() = 0;
/** Get number of vertices per face.
* @param _faceID face index
virtual int getFaceSize(int _faceID) const = 0;
/** Get a single vertex-index entry of a face.
* @param _faceID face index
* @param _faceCorner vertex corner of the face
* @param _attrID attribute channel
* @return index-data if successful, -1 otherwise
virtual int getSingleFaceAttr(int _faceID, int _faceCorner, int _attrID);
/** Get an index buffer of a face for a specific attribute channel.
* @param _faceID face index
* @param _attrID attribute channel
* @param _out pointer to output buffer, use getFaceSize(_faceID) to get the size needed to store face data
* @return true if successful, false otherwise
virtual bool getFaceAttr(int _faceID, int _attrID, int* _out) {return false;}
/** Get an index buffer of a face for a specific attribute channel.
* @param _faceID face index
* @param _attrID attribute channel
* @return array data of size "getFaceSize(_faceID)", allowed to return 0 when array data not permanently available in memory
virtual int* getFaceAttr(int _faceID, int _attrID) {return 0;}
class MeshCompilerDefaultFaceInput : public MeshCompilerFaceInput
MeshCompilerDefaultFaceInput(int _numFaces, int _numIndices);
virtual ~MeshCompilerDefaultFaceInput(){}
int getNumFaces() {return numFaces_;}
int getNumIndices() {return numIndices_;}
int getFaceSize(int _faceID) const {return faceSize_[_faceID];}
int getSingleFaceAttr(int _faceID, int _faceCorner, int _attrID);
bool getFaceAttr(int _faceID, int _attrID, int* _out);
void dbgWriteToObjFile(FILE* _file, int _posAttrID = 0, int _normalAttrID = -1, int _texcAttrID = -1);
void setFaceData(int _faceID, int _size, int* _data, int _attrID = 0);
int numFaces_,
// input data is stored in a sequence stream
// face offsets may not be in sequence
std::vector<int> faceOffset_;
std::vector<int> faceSize_;
// face index buffer for each vertex attribute
std::vector<int> faceData_[16];
class MeshCompiler
MeshCompiler(const VertexDeclaration& _decl);
virtual ~MeshCompiler();
/** set input vertex positions
* @param _num Number of vertex positions
* @param _data Pointer to vertex data
* @param _stride Difference in bytes between two vertex positions in _data. Default value 0 indicates a tight float3 position array without any other data or memory alignment.
* @param _internalCopy Memory optimization flag: select true if the provided data address is only temporarily valid. Otherwise an internal copy must be made.
void setVertices(int _num, const void* _data, int _stride = 0, bool _internalCopy = false);
/** set input normals
void setNormals(int _num, const void* _data, int _stride = 0, bool _internalCopy = false);
/** set input texture coords
void setTexCoords(int _num, const void* _data, int _stride = 0, bool _internalCopy = false);
/** Set custom input attribute.
* Alternatively allocates an internal buffer only, such that data can be provided via setAttrib().
* @param _attrIdx Attribute id from VertexDeclaration
* @param _num Number of attributes
* @param _data Input data buffer, may be null to only
* @param _stride Offset difference in bytes to the next attribute in _data. Default value 0 indicates no data alignment/memory packing.
* @param _internalCopy Create an internal buffer and make a copy _data
void setAttribVec(int _attrIdx, int _num, const void* _data, int _stride = 0, bool _internalCopy = false);
/** set one single vertex
setVertices with internalCopy = true must be called before
to have an effect
void setVertex(int _v, float* _f);
void setVertex(int _v, float _x, float _y, float _z, float _w);
void setAttrib(int _attrIdx, int _v, const void* _data);
/** set number of faces and indices
* @param _numFaces Number of faces.
* @param _numIndices Number of indices, i.e. 3 * numFaces for triangle meshes. Value 0 accepted if unknown (performance hit)
void setNumFaces(const int _numFaces, const int _numIndices);
/** Set index buffer for a triangle mesh.
* This should only be used if the input vertex buffer is interleaved already.
* @param _numTris Number of triangles.
* @param _indexSize Size in bytes of one index.
* @param _indices Pointer to a buffer containing the index data.
void setIndexBufferInterleaved(int _numTris, int _indexSize, const void* _indices);
void setFaceVerts(int _i, int _v0, int _v1, int _v2);
void setFaceVerts(int _i, int _numEdges, int* _v);
void setFaceNormals(int _i, int _v0, int _v1, int _v2);
void setFaceNormals(int _i, int _numEdges, int* _v);
void setFaceTexCoords(int _i, int _v0, int _v1, int _v2);
void setFaceTexCoords(int _i, int _numEdges, int* _v);
void setFaceAttrib(int _i, int _v0, int _v1, int _v2, int _attrID);
void setFaceAttrib(int _i, int _numEdges, int* _v, int _attrID);
void setFaceInterleaved(int _it, int _v0, int _v1, int _v2);
void setFaceInterleaved(int _it, int _numEdges, int* _v);
/** Specify face groups.
* Faces with the same group ID will be chunked together in the sorting process.
* This feature may be used for material/texture subsets.
* @param _i Face ID
* @param _groupID Custom group ID
void setFaceGroup(int _i, int _groupID);
inline int getFaceSize(const int _i) const
// return faceInput_->getFaceSize(_i);
return faceSize_[_i];
/* \brief Build draw vertex + index buffer.
* @param _optimizeVCache Reorder faces for optimized vcache usage. Low performance hit
* @param _needPerFaceAttribute User wants to set per-face attributes in draw vertex buffer. The first referenced vertex of each face can be used to store per-face data. Big performance hit
void build(bool _optimizeVCache = true, bool _needPerFaceAttribute = false);
/* \brief Get vertex buffer ready for rendering.
* Query final vertex buffer data.
* Support vertex buffer batch uploads.
* @param _dst [out] Pointer to memory address where the vertex buffer should be copied to
* @param _offset Begin of vertex buffer batch
* @param _range Size of vertex buffer batch. Copies rest of buffer if _range < 0.
void getVertexBuffer(void* _dst, const int _offset = 0, const int _range = -1);
/* Get index buffer ready for rendering.
* @param _dst Pointer to memory address where the index buffer should be copied to
void getIndexBuffer(void* _dst) const;
/** Get number of triangles in final buffer.
int getNumTriangles() const;
/** Get vertex in final draw vertex buffer.
void getVertex(int _id, void* _out) const;
/** Get index in final draw index buffer.
int getIndex(int _i) const;
/** Mapping from draw vertex id -> input vertex id
* @param _i Vertex ID in draw buffer
* @param _faceID [out] Face ID in face input buffer
* @param _cornerID [out] Corner of face corresponding to vertex.
void mapToOriginalVertexID(const int _i, int& _faceID, int& _cornerID) const;
/** Mapping from draw tri id -> input face id
* @param _triID Triangle ID in draw index buffer
* @return Input Face ID
int mapToOriginalFaceID(const int _triID) const;
/** Mapping from input vertex id -> draw vertex id
* @param _faceID Face ID in input data
* @param _cornerID Corner of face
* @return Draw Vertex ID in output vertex buffer
int mapToDrawVertexID(const int _faceID, const int _cornerID) const;
/** Mapping from input Face id -> draw vertex id
* @param _faceID Face ID in input data
* @param _k triangle no. associated to face, offset 0
* @param _numTrisOut [out] Number of triangles associated to face (if input face was n-poly)
* @return Draw Triangle ID in output vertex buffer
int mapToDrawTriID(const int _faceID, const int _k = 0, int* _numTrisOut = 0) const;
// fast update functions if input data changed
void updateFace(int _faceID);
void updateFaces();
// subset/group management
struct Subset
int id;
unsigned int startIndex;
unsigned int numTris;
unsigned int numFaces;
unsigned int startFace; // index into sorted list
/// get subset ID of a group
int findGroupSubset(int _groupID);
int getFaceGroup(int _faceID) const;
int getTriGroup(int _triID) const;
int getNumSubsets() const {return subsets_.size();}
const Subset* getSubset(int _i) const;
void computeAdjacency();
void splitVertices();
// small helper functions
/** i: face index
j: corner index
_out: output vertex (index for each attribute)
void getInputFaceVertex(int _face, int _corner, int* _out);
int getInputIndex(const int _face, const int _corner, const int _attrId) const;
// ====================================================
// input data
// vertex buffer input
struct VertexElementInput
/// mem alloc if attribute buffer managed by this class
char* internalBuf;
/** address to data input, will not be released by MeshCompiler
- may be an external address provided by user of class
const char* data;
/// # elements in buffer
int count;
/// offset in bytes from one element to the next
int stride;
/// size in bytes of one attribute
int attrSize;
// vertex data access
/// read a vertex element
void getElementData(int _idx, void* _dst) const;
// input vertex data
VertexElementInput input_[16];
// convenient attribute indices
int inputIDPos_; // index of positions into input_ array
int inputIDNorm_; // index of normals into input_ array
int inputIDTexC_; // index of texcoords into input_ array
int numAttributes_;
VertexDeclaration decl_;
// input face data
int numFaces_,
bool interleavedInput_; // is input vertex buffer interleaved
std::vector<int> faceStart_; // start position in buf for each face
std::vector<short> faceSize_; // face size, copy of faceInput_->getFaceSize() for better performance
int maxFaceCorners_; // max(faceCorners_)
std::vector<int> faceGroupIDs_; // group id for each face (optional input)
int curFaceInputPos_; // current # indices set by user
MeshCompilerFaceInput* faceInput_; // face data input interface
bool deleteFaceInputeData_; // delete if face input data internally created
std::vector<int> faceBufSplit_; // index buffer for the interleaved vertex buffer
std::vector<int> faceRotCount_; // # rotation ccw face rotation applied, handled internally by getInputIndexOffset
std::vector<int> faceSortMap_; // face IDs sorted by group; maps sortFaceID -> FaceID
int numTris_;
std::vector<int> triIndexBuffer_; // triangulated index buffer with interleaved vertices
// face grouping with subsets for per-face materials
int numSubsets_;
std::vector<Subset> subsets_;
std::map<int, int> subsetIDMap_; // maps groupId -> subsetID
// =====================================================
struct AdjacencyList
void init(int n);
int getAdj(int i, int k) const;
int getCount(int i) const;
int* start; // index to adjacency buffer
int* count; // # of adjacent faces
int* buf; // adjacency data
int bufSize; // size of buf
int num; // # adjacency entries
void dbgdump(FILE* file) const;
// adjacency list: vertex -> faces
AdjacencyList adjacencyVert_;
// adjacency: face -> faces
AdjacencyList adjacencyFace_;
struct VertexSplitter
// worst case split: num entries in vertex adj list
// estBufferIncrease: if numWorstCase == 0, then we estimate an increase in vertex buffer by this percentage
VertexSplitter(int numAttribs,
int numVerts,
int numWorstCase = 0,
float estBufferIncrease = 0.5f);
/// returns a unique index for a vertex-attribute combination
int split(int* vertex);
int numAttribs;
/// number of vertex combinations currently in use
int numVerts;
/** split list format:
for each vertex: [next split, attribute ids]
next split: -1 -> not split yet
i -> index into split list for next combination
with the same vertex position id (single linked list)
attribute ids:
array of attribute indices into input buffers,
that makes up the complete vertex
-1 -> vertex not used yet (relevant for split() only)
// int* splits;
std::vector<int> splits;
// split list access
int getNext(int id);
int* getAttribs(int id);
void setNext(int id, int next);
void setAttribs(int id, int* attr);
VertexSplitter* splitter_;
// =====================================================
// mappings
/// maps from triangle ID to sorted face ID
std::vector<int> triToSortFaceMap_;
/// maps from optimized tri ID to unoptimized tri ID
std::vector<int> triOptMap_;
/// vertex index in vbo -> input (face id, corner id) pair
std::vector<std::pair<int, int> > vertexMap_;
/// input face index -> output tri index
std::vector<int> faceToTriMap_;
// =====================================================
// final buffers used for drawing
/// # vertices in vbo
int numDrawVerts_;
/// index buffer
int* indices_;
// return interleaved vertex id for input buffers
int getInputIndexSplit(const int _face, const int _corner) const;
void setInputIndexSplit(const int _face, const int _corner, const int _val);
int mapTriToInputFace(int _tri);
int getInputIndexOffset(const int _face, const int _corner, const bool _rotation = true) const;
void forceUnsharedFaceVertex();
void triangulate();
void sortFacesByGroup();
void optimize();
void createVertexMap();
void createFaceMap();
// debugging tools
void dbgdump(const char* _filename) const;
void dbgdumpObj(const char* _filename) const;
void dbgdumpAdjList(const char* _filename) const;
int getMemoryUsage() const;
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