ic
/
magnum
mirror of https://github.com/mosra/magnum.git
6
0
Fork 0
Code Issues Projects Releases Wiki Activity
Browse Source

Class for building meshes from scratch or prefabricated data.

vectorfields
Vladimír Vondruš 16 years ago
parent
12783de1ec
commit
c30872a471
4 changed files with 496 additions and 0 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 308
      src/MeshBuilder.h
  2. 1
      src/Test/CMakeLists.txt
  3. 153
      src/Test/MeshBuilderTest.cpp
  4. 34
      src/Test/MeshBuilderTest.h

308
src/MeshBuilder.h
Unescape View File

@ -0,0 +1,308 @@
#ifndef Magnum_MeshBuilder_h
#define Magnum_MeshBuilder_h
/*
Copyright © 2010 Vladimír Vondruš <mosra@centrum.cz>
This file is part of Magnum.
Magnum is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License version 3
only, as published by the Free Software Foundation.
Magnum is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License version 3 for more details.
*/
/** @file
* @brief Class Magnum::MeshBuilder
*/
#include <set>
#include <map>
#include "Buffer.h"
#include "IndexedMesh.h"
namespace Magnum {
/**
@brief Mesh builder
Class for building meshes with triangle primitive from scratch or from
prefabricated data and modifying them (adding/removing faces, cleaning duplicate
vertices etc.).
Vertex template can be absolutely anything (single integer, structure, class)
but it must have at least operator== implemented.
*/
template<class Vertex> class MeshBuilder {
public:
/** @brief Triangle face */
struct Face {
/** @brief Implicit constructor */
Face() {}
/** @brief Constructor */
Face(Vertex* first, Vertex* second, Vertex* third) {
vertices[0] = first;
vertices[1] = second;
vertices[2] = third;
}
/** @brief Vertex data */
Vertex* vertices[3];
};
/**
* @brief Destructor
*
* Removed all vertices and faces.
*/
inline virtual ~MeshBuilder() { clear(); }
/**
* @brief Clear mesh data
*
* Should be called after the mesh is built and the builder is not
* needed. This function is also automatically called in destructor or
* when calling setData().
*/
void clear() {
for(typename std::set<Vertex*>::iterator it = _vertices.begin(); it != _vertices.end(); ++it)
delete *it;
for(typename std::set<Face*>::iterator it = _faces.begin(); it != _faces.end(); ++it)
delete *it;
_vertices.clear();
_faces.clear();
vertexFaces.clear();
}
/** @brief Array with vertices */
inline const std::set<Vertex*>& vertices() const { return _vertices; }
/** @brief Array with faces */
inline const std::set<Face*>& faces() const { return _faces; }
/**
* @brief Set mesh data
* @param vertices Vertices
* @param indices Vertex indices
* @param vertexCount Vertex count
* @param indexCount Index count
*
* Replaces mesh builder data with given data. Type of indices is
* detected from given pointer.
*/
inline void setData(const Vertex* vertices, const GLubyte* indices, GLsizei vertexCount, GLsizei indexCount) {
setData<GLubyte>(vertices, indices, vertexCount, indexCount, GL_UNSIGNED_BYTE);
}
/** @copydoc setData() */
inline void setData(const Vertex* vertices, const GLushort* indices, GLsizei vertexCount, GLsizei indexCount) {
setData<GLushort>(vertices, indices, vertexCount, indexCount, GL_UNSIGNED_SHORT);
}
/** @copydoc setData() */
inline void setData(const Vertex* vertices, const GLuint* indices, GLsizei vertexCount, GLsizei indexCount) {
setData<GLuint>(vertices, indices, vertexCount, indexCount, GL_UNSIGNED_INT);
}
/**
* @brief Remove face from the mesh
* @param face Pointer to face which to remove
*
* If face vertices are not shared with another face, they are removed
* too.
*/
void removeFace(Face* face) {
/* Remove face from vertexFaces */
for(int i = 0; i != 3; ++i) {
typename std::multimap<Vertex*, Face*>::iterator it = vertexFaces.lower_bound(face->vertices[i]);
typename std::multimap<Vertex*, Face*>::iterator end = vertexFaces.upper_bound(face->vertices[i]);
for(; it != end; ++it) if(it->second == face) {
vertexFaces.erase(it);
break;
}
/* If the vertex is not part of any face anymore, remove it too */
if(vertexFaces.count(face->vertices[i]) == 0) {
_vertices.erase(face->vertices[i]);
delete face->vertices[i];
}
}
/* Remove face from faces and delete it */
_faces.erase(face);
delete face;
}
/**
* @brief Add face
* @param face Pointer to face which to add
*/
void addFace(Face* face) {
/* Don't insert the same face twice */
if(_faces.find(face) != _faces.end()) return;
/* Add vertex to vertexData, if it is not yet there */
for(int i = 0; i != 3; ++i)
_vertices.insert(face->vertices[i]);
/* Add vertices to vertexFaces */
for(int i = 0; i != 3; ++i)
vertexFaces.insert(std::pair<Vertex*, Face*>(face->vertices[i], face));
/* Add face to face list */
_faces.insert(face);
}
/**
* @brief Clean the mesh
*
* Removes duplicate vertices from the mesh.
*/
void cleanMesh() {
/* Vertices scheduled for deletion */
std::vector<Vertex*> trashcan;
/* Foreach all vertices and for each find similar in the rest of the array */
for(typename std::set<Vertex*>::iterator it = _vertices.begin(); it != _vertices.end(); ++it) {
typename std::set<Vertex*>::iterator next = it;
for(typename std::set<Vertex*>::iterator similarIt = ++next; similarIt != _vertices.end(); ++similarIt) {
if(**it == **similarIt) {
/* Range of faces sharing that similar vertex */
typename std::multimap<Vertex*, Face*>::iterator begin = vertexFaces.lower_bound(*similarIt);
typename std::multimap<Vertex*, Face*>::iterator end = vertexFaces.upper_bound(*similarIt);
/* Updated array of faces, now sharing the original vertex */
std::multimap<Vertex*, Face*> updatedFaces;
/* Replace similar vertex in faces with this */
for(typename std::multimap<Vertex*, Face*>::iterator faceIt = begin; faceIt != end; ++faceIt) {
for(int i = 0; i != 3; ++i) if(*similarIt == faceIt->second->vertices[i]) {
faceIt->second->vertices[i] = *it;
}
updatedFaces.insert(std::pair<Vertex*, Face*>(*it, faceIt->second));
}
/* Remove old faces, insert updated */
vertexFaces.erase(begin, end);
vertexFaces.insert(updatedFaces.begin(), updatedFaces.end());
/* Schedule vertex for deletion */
trashcan.push_back(*similarIt);
}
}
}
/* Delete all scheduled vertices */
for(typename std::vector<Vertex*>::const_iterator it = trashcan.begin(); it != trashcan.end(); ++it) {
_vertices.erase(*it);
delete *it;
}
}
/**
* @brief Build indexed mesh and fill existing buffers with it
* @param mesh Mesh. The mesh primitive is set to
* Mesh::Triangles, if it is not already, vertex and index count
* is updated to values from the builder.
* @param vertexBuffer Vertex buffer created as interleaved
* with Mesh::addBuffer(). Otherwise the behaviour is undefined.
* @param vertexBufferUsage Usage of the vertex buffer.
* @param indexBufferUsage Usage of the index buffer.
*
* Builds indexed mesh from the data and fills given mesh buffers with
* them.
* @note The mesh is @b not cleaned before building.
*/
void build(IndexedMesh* mesh, Buffer* vertexBuffer, Buffer::Usage vertexBufferUsage, Buffer::Usage indexBufferUsage) {
if(_faces.size()*3 <= 0xFF)
buildInternal<GLubyte>(mesh, vertexBuffer, vertexBufferUsage, indexBufferUsage, GL_UNSIGNED_BYTE);
else if(_faces.size()*3 <= 0xFFFF)
buildInternal<GLushort>(mesh, vertexBuffer, vertexBufferUsage, indexBufferUsage, GL_UNSIGNED_SHORT);
else
buildInternal<GLuint>(mesh, vertexBuffer, vertexBufferUsage, indexBufferUsage, GL_UNSIGNED_INT);
}
/**
* @brief Build indexed data and create new mesh from them
* @param vertexBufferUsage Usage of the vertex buffer.
* @param indexBufferUsage Usage of the index buffer.
*
* @see build(IndexedMesh*, Buffer*, Buffer::Usage, Buffer::Usage)
*/
IndexedMesh* build(Buffer::Usage vertexBufferUsage, Buffer::Usage indexBufferUsage) {
IndexedMesh mesh = new IndexedMesh(Mesh::Triangles, 0, 0, GL_UNSIGNED_BYTE);
Buffer* vertexBuffer = mesh.addBuffer(true);
build(mesh, vertexBuffer, vertexBufferUsage, indexBufferUsage);
return mesh;
}
private:
std::set<Vertex*> _vertices;
std::multimap<Vertex*, Face*> vertexFaces;
std::set<Face*> _faces;
template<class IndexType> void setData(const Vertex* vertexData, const IndexType* indices, GLsizei vertexCount, GLsizei indexCount, GLenum indexType) {
clear();
/* Map vertex indices to vertex pointers */
std::map<IndexType, Vertex*> vertexMapping;
for(IndexType i = 0; i != vertexCount; ++i) {
Vertex* v = new Vertex(vertexData[i]);
_vertices.insert(v);
vertexMapping.insert(std::pair<IndexType, Vertex*>(i, v));
}
/* Faces array */
for(IndexType i = 0; i < indexCount; i += 3) {
Face* f = new Face;
for(int ii = 0; ii != 3; ++ii) {
f->vertices[ii] = vertexMapping[indices[i+ii]];
vertexFaces.insert(std::pair<Vertex*, Face*>(f->vertices[ii], f));
}
_faces.insert(f);
}
}
template<class IndexType> void buildInternal(IndexedMesh* mesh, Buffer* vertexBuffer, Buffer::Usage vertexBufferUsage, Buffer::Usage indexBufferUsage, GLenum indexType) {
/* Update the mesh parameters */
mesh->setPrimitive(Mesh::Triangles);
mesh->setVertexCount(_vertices.size());
mesh->setIndexCount(_faces.size()*3);
mesh->setIndexType(indexType);
/* Convert vertex pointers to fixed vector and map vertex data
pointers to vertex indices */
std::vector<Vertex> vertices;
std::map<Vertex*, IndexType> indicesMapping;
IndexType i = 0;
for(typename std::set<Vertex*>::const_iterator it = _vertices.begin(); it != _vertices.end(); ++it) {
vertices.push_back(**it);
indicesMapping.insert(std::pair<Vertex*, IndexType>(*it, i++));
}
/* Create indices array */
std::vector<IndexType> indices;
indices.reserve(_faces.size()*3);
for(typename std::set<Face*>::const_iterator it = _faces.begin(); it != _faces.end(); ++it) {
for(int i = 0; i != 3; ++i)
indices.push_back(indicesMapping[(*it)->vertices[i]]);
}
/* Create mesh */
vertexBuffer->setData(sizeof(Vertex)*vertices.size(), vertices.data(), vertexBufferUsage);
mesh->indexBuffer()->setData(sizeof(IndexType)*indices.size(), indices.data(), indexBufferUsage);
}
};
}
#endif

1
src/Test/CMakeLists.txt
Unescape View File

@ -1,3 +1,4 @@
magnum_add_test(ObjectTest ObjectTest.h ObjectTest.cpp Magnum)
magnum_add_test(CameraTest CameraTest.h CameraTest.cpp Magnum)
magnum_add_test(SceneTest SceneTest.h SceneTest.cpp Magnum)
magnum_add_test(MeshBuilderTest MeshBuilderTest.h MeshBuilderTest.cpp Magnum)

153
src/Test/MeshBuilderTest.cpp
Unescape View File

@ -0,0 +1,153 @@
/*
Copyright © 2010, 2011 Vladimír Vondruš <mosra@centrum.cz>
This file is part of Magnum.
Magnum is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License version 3
only, as published by the Free Software Foundation.
Magnum is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License version 3 for more details.
*/
#include "MeshBuilderTest.h"
#include <QtTest/QTest>
#include <QtCore/QDebug>
#include "MeshBuilder.h"
QTEST_APPLESS_MAIN(Magnum::Test::MeshBuilderTest)
using namespace std;
namespace Magnum { namespace Test {
void MeshBuilderTest::setData() {
MeshBuilder<int> builder;
int vertexData[] = { 1, 2, 3, 4 };
GLubyte indices[] = { 0, 1, 2, 1, 2, 3 };
builder.setData(vertexData, indices, 4, 6);
set<int*> vertices = builder.vertices();
QVERIFY(vertices.size() == 4);
int i = 1;
for(set<int*>::const_iterator it = vertices.begin(); it != vertices.end(); ++it)
QVERIFY(**it == i++);
set<MeshBuilder<int>::Face*> faces = builder.faces();
QVERIFY(faces.size() == 2);
set<MeshBuilder<int>::Face*>::const_iterator it = faces.begin();
QVERIFY(*(*it)->vertices[0] == 1);
QVERIFY(*(*it)->vertices[1] == 2);
QVERIFY(*(*it)->vertices[2] == 3);
it++;
QVERIFY(*(*it)->vertices[0] == 2);
QVERIFY(*(*it)->vertices[1] == 3);
QVERIFY(*(*it)->vertices[2] == 4);
}
void MeshBuilderTest::addFace() {
MeshBuilder<int> builder;
int* v1 = new int(1);
int* v2 = new int(2);
int* v3 = new int(3);
int* v4 = new int(4);
MeshBuilder<int>::Face* f1 = new MeshBuilder<int>::Face(v1, v2, v3);
builder.addFace(f1);
MeshBuilder<int>::Face* f2 = new MeshBuilder<int>::Face(v2, v3, v4);
builder.addFace(f2);
set<int*> vertices;
vertices.insert(v1);
vertices.insert(v2);
vertices.insert(v3);
vertices.insert(v4);
set<MeshBuilder<int>::Face*> faces;
faces.insert(f1);
faces.insert(f2);
QVERIFY(builder.vertices() == vertices);
QVERIFY(builder.faces() == faces);
}
void MeshBuilderTest::removeFace() {
MeshBuilder<int> builder;
int* v1 = new int(1);
int* v2 = new int(2);
int* v3 = new int(3);
int* v4 = new int(4);
MeshBuilder<int>::Face* f1 = new MeshBuilder<int>::Face(v1, v2, v3);
builder.addFace(f1);
MeshBuilder<int>::Face* f2 = new MeshBuilder<int>::Face(v2, v3, v4);
builder.addFace(f2);
MeshBuilder<int>::Face* f3 = new MeshBuilder<int>::Face(v2, v3, v1);
builder.addFace(f3);
/* Remove second face */
builder.removeFace(f2);
set<int*> vertices;
vertices.insert(v1);
vertices.insert(v2);
vertices.insert(v3);
set<MeshBuilder<int>::Face*> faces;
faces.insert(f1);
faces.insert(f3);
QVERIFY(builder.vertices() == vertices);
QVERIFY(builder.faces() == faces);
/* Remove third face (vertices shouldn't change) */
builder.removeFace(f3);
faces.erase(f3);
QVERIFY(builder.vertices() == vertices);
QVERIFY(builder.faces() == faces);
}
void MeshBuilderTest::cleanMesh() {
MeshBuilder<int> builder;
int* v1 = new int(1);
int* v2 = new int(2);
int* v3 = new int(1);
int* v4 = new int(4);
MeshBuilder<int>::Face* f1 = new MeshBuilder<int>::Face(v1, v2, v3);
builder.addFace(f1);
MeshBuilder<int>::Face* f2 = new MeshBuilder<int>::Face(v2, v3, v4);
builder.addFace(f2);
builder.cleanMesh();
int* unique = (f1->vertices[2] == v1) ? v1 : v3;
set<int*> vertices;
vertices.insert(unique);
vertices.insert(v2);
vertices.insert(v4);
set<MeshBuilder<int>::Face*> faces;
faces.insert(f1);
faces.insert(f2);
/* Verify cleanup */
QVERIFY(f1->vertices[2] == unique);
QVERIFY(f2->vertices[1] == unique);
QVERIFY(builder.vertices() == vertices);
QVERIFY(builder.faces() == faces);
}
}}

34
src/Test/MeshBuilderTest.h
Unescape View File

@ -0,0 +1,34 @@
#ifndef Magnum_Test_MeshBuilderTest_h
#define Magnum_Test_MeshBuilderTest_h
/*
Copyright © 2010, 2011 Vladimír Vondruš <mosra@centrum.cz>
This file is part of Magnum.
Magnum is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License version 3
only, as published by the Free Software Foundation.
Magnum is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License version 3 for more details.
*/
#include <QtCore/QObject>
namespace Magnum { namespace Test {
class MeshBuilderTest: public QObject {
Q_OBJECT
private slots:
void setData();
void addFace();
void removeFace();
void cleanMesh();
};
}}
#endif
Write Preview
Loading…
Cancel
Save