MarchingCube 的简单实现

// // Marching Cubes Example Program // by Cory Bloyd (corysama@yahoo.com) // // A simple, portable and complete implementation of the Marching Cubes // and Marching Tetrahedrons algorithms in a single source file. // There are many ways that this code could be made faster, but the // intent is for the code to be easy to understand. // // For a description of the algorithm go to // http://astronomy.swin.edu.au/pbourke/modelling/polygonise/ // // This code is public domain. // #include "stdio.h" #include "math.h" //This program requires the OpenGL and GLUT libraries // You can obtain them for free from http://www.opengl.org #include "C:\Program Files\Microsoft Visual Studio\VC98\Include\GL\glut.h" struct GLvector { GLfloat fX; GLfloat fY; GLfloat fZ; }; //These tables are used so that everything can be done in little loops that you can look at all at once // rather than in pages and pages of unrolled code. //a2fVertexOffset lists the positions, relative to vertex0, of each of the 8 vertices of a cube static const GLfloat a2fVertexOffset[8][3] = { {0.0, 0.0, 0.0},{1.0, 0.0, 0.0},{1.0, 1.0, 0.0},{0.0, 1.0, 0.0}, {0.0, 0.0, 1.0},{1.0, 0.0, 1.0},{1.0, 1.0, 1.0},{0.0, 1.0, 1.0} }; //a2iEdgeConnection lists the index of the endpoint vertices for each of the 12 edges of the cube static const GLint a2iEdgeConnection[12][2] = { {0,1}, {1,2}, {2,3}, {3,0}, {4,5}, {5,6}, {6,7}, {7,4}, {0,4}, {1,5}, {2,6}, {3,7} }; //a2fEdgeDirection lists the direction vector (vertex1-vertex0) for each edge in the cube static const GLfloat a2fEdgeDirection[12][3] = { {1.0, 0.0, 0.0},{0.0, 1.0, 0.0},{-1.0, 0.0, 0.0},{0.0, -1.0, 0.0}, {1.0, 0.0, 0.0},{0.0, 1.0, 0.0},{-1.0, 0.0, 0.0},{0.0, -1.0, 0.0}, {0.0, 0.0, 1.0},{0.0, 0.0, 1.0},{ 0.0, 0.0, 1.0},{0.0, 0.0, 1.0} }; //a2iTetrahedronEdgeConnection lists the index of the endpoint vertices for each of the 6 edges of the tetrahedron static const GLint a2iTetrahedronEdgeConnection[6][2] = { {0,1}, {1,2}, {2,0}, {0,3}, {1,3}, {2,3} }; //a2iTetrahedronEdgeConnection lists the index of verticies from a cube // that made up each of the six tetrahedrons within the cube static const GLint a2iTetrahedronsInACube[6][4] = { {0,5,1,6}, {0,1,2,6}, {0,2,3,6}, {0,3,7,6}, {0,7,4,6}, {0,4,5,6}, }; static const GLfloat afAmbientWhite [] = {0.25, 0.25, 0.25, 1.00}; static const GLfloat afAmbientRed [] = {0.25, 0.00, 0.00, 1.00}; static const GLfloat afAmbientGreen [] = {0.00, 0.25, 0.00, 1.00}; static const GLfloat afAmbientBlue [] = {0.00, 0.00, 0.25, 1.00}; static const GLfloat afDiffuseWhite [] = {0.75, 0.75, 0.75, 1.00}; static const GLfloat afDiffuseRed [] = {0.75, 0.00, 0.00, 1.00}; static const GLfloat afDiffuseGreen [] = {0.00, 0.75, 0.00, 1.00}; static const GLfloat afDiffuseBlue [] = {0.00, 0.00, 0.75, 1.00}; static const GLfloat afSpecularWhite[] = {1.00, 1.00, 1.00, 1.00}; static const GLfloat afSpecularRed [] = {1.00, 0.25, 0.25, 1.00}; static const GLfloat afSpecularGreen[] = {0.25, 1.00, 0.25, 1.00}; static const GLfloat afSpecularBlue [] = {0.25, 0.25, 1.00, 1.00}; GLenum ePolygonMode = GL_FILL; GLint iDataSetSize = 16; GLfloat fStepSize = 1.0/iDataSetSize; GLfloat fTargetValue = 48.0; GLfloat fTime = 0.0; GLvector sSourcePoint[3]; GLboolean bSpin = true; GLboolean bMove = true; GLboolean bLight = true; void vIdle(); void vDrawScene(); void vResize(GLsizei, GLsizei); void vKeyboard(unsigned char cKey, int iX, int iY); void vSpecial(int iKey, int iX, int iY); GLvoid vPrintHelp(); GLvoid vSetTime(GLfloat fTime); GLfloat fSample1(GLfloat fX, GLfloat fY, GLfloat fZ); GLfloat fSample2(GLfloat fX, GLfloat fY, GLfloat fZ); GLfloat fSample3(GLfloat fX, GLfloat fY, GLfloat fZ); GLfloat (*fSample)(GLfloat fX, GLfloat fY, GLfloat fZ) = fSample1; GLvoid vMarchingCubes(); GLvoid vMarchCube1(GLfloat fX, GLfloat fY, GLfloat fZ, GLfloat fScale); GLvoid vMarchCube2(GLfloat fX, GLfloat fY, GLfloat fZ, GLfloat fScale); GLvoid (*vMarchCube)(GLfloat fX, GLfloat fY, GLfloat fZ, GLfloat fScale) = vMarchCube1; void main(int argc, char **argv) { GLfloat afPropertiesAmbient [] = {0.50, 0.50, 0.50, 1.00}; GLfloat afPropertiesDiffuse [] = {0.75, 0.75, 0.75, 1.00}; GLfloat afPropertiesSpecular[] = {1.00, 1.00, 1.00, 1.00}; GLsizei iWidth = 640.0; GLsizei iHeight = 480.0; glutInit(&argc, argv); glutInitWindowPosition( 0, 0); glutInitWindowSize(iWidth, iHeight); glutInitDisplayMode( GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE ); glutCreateWindow( "Marching Cubes" ); glutDisplayFunc( vDrawScene ); glutIdleFunc( vIdle ); glutReshapeFunc( vResize ); glutKeyboardFunc( vKeyboard ); glutSpecialFunc( vSpecial ); glClearColor( 0.0, 0.0, 0.0, 1.0 ); glClearDepth( 1.0 ); glEnable(GL_DEPTH_TEST); glEnable(GL_LIGHTING); glPolygonMode(GL_FRONT_AND_BACK, ePolygonMode); glLightfv( GL_LIGHT0, GL_AMBIENT, afPropertiesAmbient); glLightfv( GL_LIGHT0, GL_DIFFUSE, afPropertiesDiffuse); glLightfv( GL_LIGHT0, GL_SPECULAR, afPropertiesSpecular); glLightModelf(GL_LIGHT_MODEL_TWO_SIDE, 1.0); glEnable( GL_LIGHT0 ); glMaterialfv(GL_BACK, GL_AMBIENT, afAmbientGreen); glMaterialfv(GL_BACK, GL_DIFFUSE, afDiffuseGreen); glMaterialfv(GL_FRONT, GL_AMBIENT, afAmbientBlue); glMaterialfv(GL_FRONT, GL_DIFFUSE, afDiffuseBlue); glMaterialfv(GL_FRONT, GL_SPECULAR, afSpecularWhite); glMaterialf( GL_FRONT, GL_SHININESS, 25.0); vResize(iWidth, iHeight); vPrintHelp(); glutMainLoop(); } GLvoid vPrintHelp() { printf("Marching Cubes Example by Cory Bloyd (dejaspaminacan@my-deja.com)\n\n"); printf("+/- increase/decrease sample density\n"); printf("PageUp/PageDown increase/decrease surface value\n"); printf("s change sample function\n"); printf("c toggle marching cubes / marching tetrahedrons\n"); printf("w wireframe on/off\n"); printf("l toggle lighting / color-by-normal\n"); printf("Home spin scene on/off\n"); printf("End source point animation on/off\n"); } void vResize( GLsizei iWidth, GLsizei iHeight ) { GLfloat fAspect, fHalfWorldSize = (1.4142135623730950488016887242097/2); glViewport( 0, 0, iWidth, iHeight ); glMatrixMode (GL_PROJECTION); glLoadIdentity (); if(iWidth <= iHeight) { fAspect = (GLfloat)iHeight / (GLfloat)iWidth; glOrtho(-fHalfWorldSize, fHalfWorldSize, -fHalfWorldSize*fAspect, fHalfWorldSize*fAspect, -10*fHalfWorldSize, 10*fHalfWorldSize); } else { fAspect = (GLfloat)iWidth / (GLfloat)iHeight; glOrtho(-fHalfWorldSize*fAspect, fHalfWorldSize*fAspect, -fHalfWorldSize, fHalfWorldSize, -10*fHalfWorldSize, 10*fHalfWorldSize); } glMatrixMode( GL_MODELVIEW ); } void vKeyboard(unsigned char cKey, int iX, int iY) { switch(cKey) { case 'w' : { if(ePolygonMode == GL_LINE) { ePolygonMode = GL_FILL; } else { ePolygonMode = GL_LINE; } glPolygonMode(GL_FRONT_AND_BACK, ePolygonMode); } break;