ref: 9eaba52cafcac7c2f3bfc72d7be1f15893196be1
dir: /DoConfig/fltk/src/freeglut_geometry.cxx/
/* * freeglut_geometry.c * * Freeglut geometry rendering methods. * * Copyright (c) 1999-2010 Pawel W. Olszta. All Rights Reserved. * Written by Pawel W. Olszta, <olszta@sourceforge.net> * Creation date: Fri Dec 3 1999 * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included * in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * PAWEL W. OLSZTA BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ #include <FL/glut.H> #include <FL/math.h> #include <stdlib.h> /* * TODO BEFORE THE STABLE RELEASE: * * Following functions have been contributed by Andreas Umbach. * * glutWireCube() -- looks OK * glutSolidCube() -- OK * * Those functions have been implemented by John Fay. * * glutWireTorus() -- looks OK * glutSolidTorus() -- looks OK * glutWireDodecahedron() -- looks OK * glutSolidDodecahedron() -- looks OK * glutWireOctahedron() -- looks OK * glutSolidOctahedron() -- looks OK * glutWireTetrahedron() -- looks OK * glutSolidTetrahedron() -- looks OK * glutWireIcosahedron() -- looks OK * glutSolidIcosahedron() -- looks OK * * The Following functions have been updated by Nigel Stewart, based * on FreeGLUT 2.0.0 implementations: * * glutWireSphere() -- looks OK * glutSolidSphere() -- looks OK * glutWireCone() -- looks OK * glutSolidCone() -- looks OK */ /* -- INTERFACE FUNCTIONS -------------------------------------------------- */ /* * Draws a wireframed cube. Code contributed by Andreas Umbach <marvin@dataway.ch> */ void glutWireCube( GLdouble dSize ) { double size = dSize * 0.5; # define V(a,b,c) glVertex3d( a size, b size, c size ); # define N(a,b,c) glNormal3d( a, b, c ); /* PWO: I dared to convert the code to use macros... */ glBegin( GL_LINE_LOOP ); N( 1.0, 0.0, 0.0); V(+,-,+); V(+,-,-); V(+,+,-); V(+,+,+); glEnd(); glBegin( GL_LINE_LOOP ); N( 0.0, 1.0, 0.0); V(+,+,+); V(+,+,-); V(-,+,-); V(-,+,+); glEnd(); glBegin( GL_LINE_LOOP ); N( 0.0, 0.0, 1.0); V(+,+,+); V(-,+,+); V(-,-,+); V(+,-,+); glEnd(); glBegin( GL_LINE_LOOP ); N(-1.0, 0.0, 0.0); V(-,-,+); V(-,+,+); V(-,+,-); V(-,-,-); glEnd(); glBegin( GL_LINE_LOOP ); N( 0.0,-1.0, 0.0); V(-,-,+); V(-,-,-); V(+,-,-); V(+,-,+); glEnd(); glBegin( GL_LINE_LOOP ); N( 0.0, 0.0,-1.0); V(-,-,-); V(-,+,-); V(+,+,-); V(+,-,-); glEnd(); # undef V # undef N } /* * Draws a solid cube. Code contributed by Andreas Umbach <marvin@dataway.ch> */ void glutSolidCube( GLdouble dSize ) { double size = dSize * 0.5; # define V(a,b,c) glVertex3d( a size, b size, c size ); # define N(a,b,c) glNormal3d( a, b, c ); /* PWO: Again, I dared to convert the code to use macros... */ glBegin( GL_QUADS ); N( 1.0, 0.0, 0.0); V(+,-,+); V(+,-,-); V(+,+,-); V(+,+,+); N( 0.0, 1.0, 0.0); V(+,+,+); V(+,+,-); V(-,+,-); V(-,+,+); N( 0.0, 0.0, 1.0); V(+,+,+); V(-,+,+); V(-,-,+); V(+,-,+); N(-1.0, 0.0, 0.0); V(-,-,+); V(-,+,+); V(-,+,-); V(-,-,-); N( 0.0,-1.0, 0.0); V(-,-,+); V(-,-,-); V(+,-,-); V(+,-,+); N( 0.0, 0.0,-1.0); V(-,-,-); V(-,+,-); V(+,+,-); V(+,-,-); glEnd(); # undef V # undef N } /* * Compute lookup table of cos and sin values forming a cirle * * Notes: * It is the responsibility of the caller to free these tables * The size of the table is (n+1) to form a connected loop * The last entry is exactly the same as the first * The sign of n can be flipped to get the reverse loop */ static void fghCircleTable(double **sint,double **cost,const int n) { int i; /* Table size, the sign of n flips the circle direction */ const int size = abs(n); /* Determine the angle between samples */ const double angle = 2*M_PI/(double)( ( n == 0 ) ? 1 : n ); /* Allocate memory for n samples, plus duplicate of first entry at the end */ *sint = (double *) calloc(sizeof(double), size+1); *cost = (double *) calloc(sizeof(double), size+1); /* Bail out if memory allocation fails, fgError never returns */ if (!(*sint) || !(*cost)) { if (*sint) free(*sint); if (*cost) free(*cost); return; } /* Compute cos and sin around the circle */ (*sint)[0] = 0.0; (*cost)[0] = 1.0; for (i=1; i<size; i++) { (*sint)[i] = sin(angle*i); (*cost)[i] = cos(angle*i); } /* Last sample is duplicate of the first */ (*sint)[size] = (*sint)[0]; (*cost)[size] = (*cost)[0]; } /* * Draws a solid sphere */ void glutSolidSphere(GLdouble radius, GLint slices, GLint stacks) { int i,j; /* Adjust z and radius as stacks are drawn. */ double z0,z1; double r0,r1; /* Pre-computed circle */ double *sint1,*cost1; double *sint2,*cost2; fghCircleTable(&sint1,&cost1,-slices); fghCircleTable(&sint2,&cost2,stacks*2); /* The top stack is covered with a triangle fan */ z0 = 1.0; z1 = cost2[(stacks>0)?1:0]; r0 = 0.0; r1 = sint2[(stacks>0)?1:0]; glBegin(GL_TRIANGLE_FAN); glNormal3d(0,0,1); glVertex3d(0,0,radius); for (j=slices; j>=0; j--) { glNormal3d(cost1[j]*r1, sint1[j]*r1, z1 ); glVertex3d(cost1[j]*r1*radius, sint1[j]*r1*radius, z1*radius); } glEnd(); /* Cover each stack with a quad strip, except the top and bottom stacks */ for( i=1; i<stacks-1; i++ ) { z0 = z1; z1 = cost2[i+1]; r0 = r1; r1 = sint2[i+1]; glBegin(GL_QUAD_STRIP); for(j=0; j<=slices; j++) { glNormal3d(cost1[j]*r1, sint1[j]*r1, z1 ); glVertex3d(cost1[j]*r1*radius, sint1[j]*r1*radius, z1*radius); glNormal3d(cost1[j]*r0, sint1[j]*r0, z0 ); glVertex3d(cost1[j]*r0*radius, sint1[j]*r0*radius, z0*radius); } glEnd(); } /* The bottom stack is covered with a triangle fan */ z0 = z1; r0 = r1; glBegin(GL_TRIANGLE_FAN); glNormal3d(0,0,-1); glVertex3d(0,0,-radius); for (j=0; j<=slices; j++) { glNormal3d(cost1[j]*r0, sint1[j]*r0, z0 ); glVertex3d(cost1[j]*r0*radius, sint1[j]*r0*radius, z0*radius); } glEnd(); /* Release sin and cos tables */ free(sint1); free(cost1); free(sint2); free(cost2); } /* * Draws a wire sphere */ void glutWireSphere(GLdouble radius, GLint slices, GLint stacks) { int i,j; /* Adjust z and radius as stacks and slices are drawn. */ double r; double x,y,z; /* Pre-computed circle */ double *sint1,*cost1; double *sint2,*cost2; fghCircleTable(&sint1,&cost1,-slices ); fghCircleTable(&sint2,&cost2, stacks*2); /* Draw a line loop for each stack */ for (i=1; i<stacks; i++) { z = cost2[i]; r = sint2[i]; glBegin(GL_LINE_LOOP); for(j=0; j<=slices; j++) { x = cost1[j]; y = sint1[j]; glNormal3d(x,y,z); glVertex3d(x*r*radius,y*r*radius,z*radius); } glEnd(); } /* Draw a line loop for each slice */ for (i=0; i<slices; i++) { glBegin(GL_LINE_STRIP); for(j=0; j<=stacks; j++) { x = cost1[i]*sint2[j]; y = sint1[i]*sint2[j]; z = cost2[j]; glNormal3d(x,y,z); glVertex3d(x*radius,y*radius,z*radius); } glEnd(); } /* Release sin and cos tables */ free(sint1); free(cost1); free(sint2); free(cost2); } /* * Draws a solid cone */ void glutSolidCone( GLdouble base, GLdouble height, GLint slices, GLint stacks ) { int i,j; /* Step in z and radius as stacks are drawn. */ double z0,z1; double r0,r1; const double zStep = height / ( ( stacks > 0 ) ? stacks : 1 ); const double rStep = base / ( ( stacks > 0 ) ? stacks : 1 ); /* Scaling factors for vertex normals */ const double cosn = ( height / sqrt ( height * height + base * base )); const double sinn = ( base / sqrt ( height * height + base * base )); /* Pre-computed circle */ double *sint,*cost; fghCircleTable(&sint,&cost,-slices); /* Cover the circular base with a triangle fan... */ z0 = 0.0; z1 = zStep; r0 = base; r1 = r0 - rStep; glBegin(GL_TRIANGLE_FAN); glNormal3d(0.0,0.0,-1.0); glVertex3d(0.0,0.0, z0 ); for (j=0; j<=slices; j++) glVertex3d(cost[j]*r0, sint[j]*r0, z0); glEnd(); /* Cover each stack with a quad strip, except the top stack */ for( i=0; i<stacks-1; i++ ) { glBegin(GL_QUAD_STRIP); for(j=0; j<=slices; j++) { glNormal3d(cost[j]*sinn, sint[j]*sinn, cosn); glVertex3d(cost[j]*r0, sint[j]*r0, z0 ); glVertex3d(cost[j]*r1, sint[j]*r1, z1 ); } z0 = z1; z1 += zStep; r0 = r1; r1 -= rStep; glEnd(); } /* The top stack is covered with individual triangles */ glBegin(GL_TRIANGLES); glNormal3d(cost[0]*sinn, sint[0]*sinn, cosn); for (j=0; j<slices; j++) { glVertex3d(cost[j+0]*r0, sint[j+0]*r0, z0 ); glVertex3d(0, 0, height); glNormal3d(cost[j+1]*sinn, sint[j+1]*sinn, cosn ); glVertex3d(cost[j+1]*r0, sint[j+1]*r0, z0 ); } glEnd(); /* Release sin and cos tables */ free(sint); free(cost); } /* * Draws a wire cone */ void glutWireCone( GLdouble base, GLdouble height, GLint slices, GLint stacks) { int i,j; /* Step in z and radius as stacks are drawn. */ double z = 0.0; double r = base; const double zStep = height / ( ( stacks > 0 ) ? stacks : 1 ); const double rStep = base / ( ( stacks > 0 ) ? stacks : 1 ); /* Scaling factors for vertex normals */ const double cosn = ( height / sqrt ( height * height + base * base )); const double sinn = ( base / sqrt ( height * height + base * base )); /* Pre-computed circle */ double *sint,*cost; fghCircleTable(&sint,&cost,-slices); /* Draw the stacks... */ for (i=0; i<stacks; i++) { glBegin(GL_LINE_LOOP); for( j=0; j<slices; j++ ) { glNormal3d(cost[j]*sinn, sint[j]*sinn, cosn); glVertex3d(cost[j]*r, sint[j]*r, z ); } glEnd(); z += zStep; r -= rStep; } /* Draw the slices */ r = base; glBegin(GL_LINES); for (j=0; j<slices; j++) { glNormal3d(cost[j]*sinn, sint[j]*sinn, cosn ); glVertex3d(cost[j]*r, sint[j]*r, 0.0 ); glVertex3d(0.0, 0.0, height); } glEnd(); /* Release sin and cos tables */ free(sint); free(cost); } /* * Draws a solid cylinder */ void glutSolidCylinder(GLdouble radius, GLdouble height, GLint slices, GLint stacks) { int i,j; /* Step in z and radius as stacks are drawn. */ double z0,z1; const double zStep = height / ( ( stacks > 0 ) ? stacks : 1 ); /* Pre-computed circle */ double *sint,*cost; fghCircleTable(&sint,&cost,-slices); /* Cover the base and top */ glBegin(GL_TRIANGLE_FAN); glNormal3d(0.0, 0.0, -1.0 ); glVertex3d(0.0, 0.0, 0.0 ); for (j=0; j<=slices; j++) glVertex3d(cost[j]*radius, sint[j]*radius, 0.0); glEnd(); glBegin(GL_TRIANGLE_FAN); glNormal3d(0.0, 0.0, 1.0 ); glVertex3d(0.0, 0.0, height); for (j=slices; j>=0; j--) glVertex3d(cost[j]*radius, sint[j]*radius, height); glEnd(); /* Do the stacks */ z0 = 0.0; z1 = zStep; for (i=1; i<=stacks; i++) { if (i==stacks) z1 = height; glBegin(GL_QUAD_STRIP); for (j=0; j<=slices; j++ ) { glNormal3d(cost[j], sint[j], 0.0 ); glVertex3d(cost[j]*radius, sint[j]*radius, z0 ); glVertex3d(cost[j]*radius, sint[j]*radius, z1 ); } glEnd(); z0 = z1; z1 += zStep; } /* Release sin and cos tables */ free(sint); free(cost); } /* * Draws a wire cylinder */ void glutWireCylinder(GLdouble radius, GLdouble height, GLint slices, GLint stacks) { int i,j; /* Step in z and radius as stacks are drawn. */ double z = 0.0; const double zStep = height / ( ( stacks > 0 ) ? stacks : 1 ); /* Pre-computed circle */ double *sint,*cost; fghCircleTable(&sint,&cost,-slices); /* Draw the stacks... */ for (i=0; i<=stacks; i++) { if (i==stacks) z = height; glBegin(GL_LINE_LOOP); for( j=0; j<slices; j++ ) { glNormal3d(cost[j], sint[j], 0.0); glVertex3d(cost[j]*radius, sint[j]*radius, z ); } glEnd(); z += zStep; } /* Draw the slices */ glBegin(GL_LINES); for (j=0; j<slices; j++) { glNormal3d(cost[j], sint[j], 0.0 ); glVertex3d(cost[j]*radius, sint[j]*radius, 0.0 ); glVertex3d(cost[j]*radius, sint[j]*radius, height); } glEnd(); /* Release sin and cos tables */ free(sint); free(cost); } /* * Draws a wire torus */ void glutWireTorus( GLdouble dInnerRadius, GLdouble dOuterRadius, GLint nSides, GLint nRings ) { double iradius = dInnerRadius, oradius = dOuterRadius, phi, psi, dpsi, dphi; double *vertex, *normal; int i, j; double spsi, cpsi, sphi, cphi ; if ( nSides < 1 ) nSides = 1; if ( nRings < 1 ) nRings = 1; /* Allocate the vertices array */ vertex = (double *)calloc( sizeof(double), 3 * nSides * nRings ); normal = (double *)calloc( sizeof(double), 3 * nSides * nRings ); glPushMatrix(); dpsi = 2.0 * M_PI / (double)nRings ; dphi = -2.0 * M_PI / (double)nSides ; psi = 0.0; for( j=0; j<nRings; j++ ) { cpsi = cos ( psi ) ; spsi = sin ( psi ) ; phi = 0.0; for( i=0; i<nSides; i++ ) { int offset = 3 * ( j * nSides + i ) ; cphi = cos ( phi ) ; sphi = sin ( phi ) ; *(vertex + offset + 0) = cpsi * ( oradius + cphi * iradius ) ; *(vertex + offset + 1) = spsi * ( oradius + cphi * iradius ) ; *(vertex + offset + 2) = sphi * iradius ; *(normal + offset + 0) = cpsi * cphi ; *(normal + offset + 1) = spsi * cphi ; *(normal + offset + 2) = sphi ; phi += dphi; } psi += dpsi; } for( i=0; i<nSides; i++ ) { glBegin( GL_LINE_LOOP ); for( j=0; j<nRings; j++ ) { int offset = 3 * ( j * nSides + i ) ; glNormal3dv( normal + offset ); glVertex3dv( vertex + offset ); } glEnd(); } for( j=0; j<nRings; j++ ) { glBegin(GL_LINE_LOOP); for( i=0; i<nSides; i++ ) { int offset = 3 * ( j * nSides + i ) ; glNormal3dv( normal + offset ); glVertex3dv( vertex + offset ); } glEnd(); } free ( vertex ) ; free ( normal ) ; glPopMatrix(); } /* * Draws a solid torus */ void glutSolidTorus( GLdouble dInnerRadius, GLdouble dOuterRadius, GLint nSides, GLint nRings ) { double iradius = dInnerRadius, oradius = dOuterRadius, phi, psi, dpsi, dphi; double *vertex, *normal; int i, j; double spsi, cpsi, sphi, cphi ; if ( nSides < 1 ) nSides = 1; if ( nRings < 1 ) nRings = 1; /* Increment the number of sides and rings to allow for one more point than surface */ nSides ++ ; nRings ++ ; /* Allocate the vertices array */ vertex = (double *)calloc( sizeof(double), 3 * nSides * nRings ); normal = (double *)calloc( sizeof(double), 3 * nSides * nRings ); glPushMatrix(); dpsi = 2.0 * M_PI / (double)(nRings - 1) ; dphi = -2.0 * M_PI / (double)(nSides - 1) ; psi = 0.0; for( j=0; j<nRings; j++ ) { cpsi = cos ( psi ) ; spsi = sin ( psi ) ; phi = 0.0; for( i=0; i<nSides; i++ ) { int offset = 3 * ( j * nSides + i ) ; cphi = cos ( phi ) ; sphi = sin ( phi ) ; *(vertex + offset + 0) = cpsi * ( oradius + cphi * iradius ) ; *(vertex + offset + 1) = spsi * ( oradius + cphi * iradius ) ; *(vertex + offset + 2) = sphi * iradius ; *(normal + offset + 0) = cpsi * cphi ; *(normal + offset + 1) = spsi * cphi ; *(normal + offset + 2) = sphi ; phi += dphi; } psi += dpsi; } glBegin( GL_QUADS ); for( i=0; i<nSides-1; i++ ) { for( j=0; j<nRings-1; j++ ) { int offset = 3 * ( j * nSides + i ) ; glNormal3dv( normal + offset ); glVertex3dv( vertex + offset ); glNormal3dv( normal + offset + 3 ); glVertex3dv( vertex + offset + 3 ); glNormal3dv( normal + offset + 3 * nSides + 3 ); glVertex3dv( vertex + offset + 3 * nSides + 3 ); glNormal3dv( normal + offset + 3 * nSides ); glVertex3dv( vertex + offset + 3 * nSides ); } } glEnd(); free ( vertex ) ; free ( normal ) ; glPopMatrix(); } /* * */ void glutWireDodecahedron( void ) { /* Magic Numbers: It is possible to create a dodecahedron by attaching two pentagons to each face of * of a cube. The coordinates of the points are: * (+-x,0, z); (+-1, 1, 1); (0, z, x ) * where x = (-1 + sqrt(5))/2, z = (1 + sqrt(5))/2 or * x = 0.61803398875 and z = 1.61803398875. */ glBegin ( GL_LINE_LOOP ) ; glNormal3d ( 0.0, 0.525731112119, 0.850650808354 ) ; glVertex3d ( 0.0, 1.61803398875, 0.61803398875 ) ; glVertex3d ( -1.0, 1.0, 1.0 ) ; glVertex3d ( -0.61803398875, 0.0, 1.61803398875 ) ; glVertex3d ( 0.61803398875, 0.0, 1.61803398875 ) ; glVertex3d ( 1.0, 1.0, 1.0 ) ; glEnd () ; glBegin ( GL_LINE_LOOP ) ; glNormal3d ( 0.0, 0.525731112119, -0.850650808354 ) ; glVertex3d ( 0.0, 1.61803398875, -0.61803398875 ) ; glVertex3d ( 1.0, 1.0, -1.0 ) ; glVertex3d ( 0.61803398875, 0.0, -1.61803398875 ) ; glVertex3d ( -0.61803398875, 0.0, -1.61803398875 ) ; glVertex3d ( -1.0, 1.0, -1.0 ) ; glEnd () ; glBegin ( GL_LINE_LOOP ) ; glNormal3d ( 0.0, -0.525731112119, 0.850650808354 ) ; glVertex3d ( 0.0, -1.61803398875, 0.61803398875 ) ; glVertex3d ( 1.0, -1.0, 1.0 ) ; glVertex3d ( 0.61803398875, 0.0, 1.61803398875 ) ; glVertex3d ( -0.61803398875, 0.0, 1.61803398875 ) ; glVertex3d ( -1.0, -1.0, 1.0 ) ; glEnd () ; glBegin ( GL_LINE_LOOP ) ; glNormal3d ( 0.0, -0.525731112119, -0.850650808354 ) ; glVertex3d ( 0.0, -1.61803398875, -0.61803398875 ) ; glVertex3d ( -1.0, -1.0, -1.0 ) ; glVertex3d ( -0.61803398875, 0.0, -1.61803398875 ) ; glVertex3d ( 0.61803398875, 0.0, -1.61803398875 ) ; glVertex3d ( 1.0, -1.0, -1.0 ) ; glEnd () ; glBegin ( GL_LINE_LOOP ) ; glNormal3d ( 0.850650808354, 0.0, 0.525731112119 ) ; glVertex3d ( 0.61803398875, 0.0, 1.61803398875 ) ; glVertex3d ( 1.0, -1.0, 1.0 ) ; glVertex3d ( 1.61803398875, -0.61803398875, 0.0 ) ; glVertex3d ( 1.61803398875, 0.61803398875, 0.0 ) ; glVertex3d ( 1.0, 1.0, 1.0 ) ; glEnd () ; glBegin ( GL_LINE_LOOP ) ; glNormal3d ( -0.850650808354, 0.0, 0.525731112119 ) ; glVertex3d ( -0.61803398875, 0.0, 1.61803398875 ) ; glVertex3d ( -1.0, 1.0, 1.0 ) ; glVertex3d ( -1.61803398875, 0.61803398875, 0.0 ) ; glVertex3d ( -1.61803398875, -0.61803398875, 0.0 ) ; glVertex3d ( -1.0, -1.0, 1.0 ) ; glEnd () ; glBegin ( GL_LINE_LOOP ) ; glNormal3d ( 0.850650808354, 0.0, -0.525731112119 ) ; glVertex3d ( 0.61803398875, 0.0, -1.61803398875 ) ; glVertex3d ( 1.0, 1.0, -1.0 ) ; glVertex3d ( 1.61803398875, 0.61803398875, 0.0 ) ; glVertex3d ( 1.61803398875, -0.61803398875, 0.0 ) ; glVertex3d ( 1.0, -1.0, -1.0 ) ; glEnd () ; glBegin ( GL_LINE_LOOP ) ; glNormal3d ( -0.850650808354, 0.0, -0.525731112119 ) ; glVertex3d ( -0.61803398875, 0.0, -1.61803398875 ) ; glVertex3d ( -1.0, -1.0, -1.0 ) ; glVertex3d ( -1.61803398875, -0.61803398875, 0.0 ) ; glVertex3d ( -1.61803398875, 0.61803398875, 0.0 ) ; glVertex3d ( -1.0, 1.0, -1.0 ) ; glEnd () ; glBegin ( GL_LINE_LOOP ) ; glNormal3d ( 0.525731112119, 0.850650808354, 0.0 ) ; glVertex3d ( 1.61803398875, 0.61803398875, 0.0 ) ; glVertex3d ( 1.0, 1.0, -1.0 ) ; glVertex3d ( 0.0, 1.61803398875, -0.61803398875 ) ; glVertex3d ( 0.0, 1.61803398875, 0.61803398875 ) ; glVertex3d ( 1.0, 1.0, 1.0 ) ; glEnd () ; glBegin ( GL_LINE_LOOP ) ; glNormal3d ( 0.525731112119, -0.850650808354, 0.0 ) ; glVertex3d ( 1.61803398875, -0.61803398875, 0.0 ) ; glVertex3d ( 1.0, -1.0, 1.0 ) ; glVertex3d ( 0.0, -1.61803398875, 0.61803398875 ) ; glVertex3d ( 0.0, -1.61803398875, -0.61803398875 ) ; glVertex3d ( 1.0, -1.0, -1.0 ) ; glEnd () ; glBegin ( GL_LINE_LOOP ) ; glNormal3d ( -0.525731112119, 0.850650808354, 0.0 ) ; glVertex3d ( -1.61803398875, 0.61803398875, 0.0 ) ; glVertex3d ( -1.0, 1.0, 1.0 ) ; glVertex3d ( 0.0, 1.61803398875, 0.61803398875 ) ; glVertex3d ( 0.0, 1.61803398875, -0.61803398875 ) ; glVertex3d ( -1.0, 1.0, -1.0 ) ; glEnd () ; glBegin ( GL_LINE_LOOP ) ; glNormal3d ( -0.525731112119, -0.850650808354, 0.0 ) ; glVertex3d ( -1.61803398875, -0.61803398875, 0.0 ) ; glVertex3d ( -1.0, -1.0, -1.0 ) ; glVertex3d ( 0.0, -1.61803398875, -0.61803398875 ) ; glVertex3d ( 0.0, -1.61803398875, 0.61803398875 ) ; glVertex3d ( -1.0, -1.0, 1.0 ) ; glEnd () ; } /* * */ void glutSolidDodecahedron( void ) { /* Magic Numbers: It is possible to create a dodecahedron by attaching two pentagons to each face of * of a cube. The coordinates of the points are: * (+-x,0, z); (+-1, 1, 1); (0, z, x ) * where x = (-1 + sqrt(5))/2, z = (1 + sqrt(5))/2 or * x = 0.61803398875 and z = 1.61803398875. */ glBegin ( GL_POLYGON ) ; glNormal3d ( 0.0, 0.525731112119, 0.850650808354 ) ; glVertex3d ( 0.0, 1.61803398875, 0.61803398875 ) ; glVertex3d ( -1.0, 1.0, 1.0 ) ; glVertex3d ( -0.61803398875, 0.0, 1.61803398875 ) ; glVertex3d ( 0.61803398875, 0.0, 1.61803398875 ) ; glVertex3d ( 1.0, 1.0, 1.0 ) ; glEnd () ; glBegin ( GL_POLYGON ) ; glNormal3d ( 0.0, 0.525731112119, -0.850650808354 ) ; glVertex3d ( 0.0, 1.61803398875, -0.61803398875 ) ; glVertex3d ( 1.0, 1.0, -1.0 ) ; glVertex3d ( 0.61803398875, 0.0, -1.61803398875 ) ; glVertex3d ( -0.61803398875, 0.0, -1.61803398875 ) ; glVertex3d ( -1.0, 1.0, -1.0 ) ; glEnd () ; glBegin ( GL_POLYGON ) ; glNormal3d ( 0.0, -0.525731112119, 0.850650808354 ) ; glVertex3d ( 0.0, -1.61803398875, 0.61803398875 ) ; glVertex3d ( 1.0, -1.0, 1.0 ) ; glVertex3d ( 0.61803398875, 0.0, 1.61803398875 ) ; glVertex3d ( -0.61803398875, 0.0, 1.61803398875 ) ; glVertex3d ( -1.0, -1.0, 1.0 ) ; glEnd () ; glBegin ( GL_POLYGON ) ; glNormal3d ( 0.0, -0.525731112119, -0.850650808354 ) ; glVertex3d ( 0.0, -1.61803398875, -0.61803398875 ) ; glVertex3d ( -1.0, -1.0, -1.0 ) ; glVertex3d ( -0.61803398875, 0.0, -1.61803398875 ) ; glVertex3d ( 0.61803398875, 0.0, -1.61803398875 ) ; glVertex3d ( 1.0, -1.0, -1.0 ) ; glEnd () ; glBegin ( GL_POLYGON ) ; glNormal3d ( 0.850650808354, 0.0, 0.525731112119 ) ; glVertex3d ( 0.61803398875, 0.0, 1.61803398875 ) ; glVertex3d ( 1.0, -1.0, 1.0 ) ; glVertex3d ( 1.61803398875, -0.61803398875, 0.0 ) ; glVertex3d ( 1.61803398875, 0.61803398875, 0.0 ) ; glVertex3d ( 1.0, 1.0, 1.0 ) ; glEnd () ; glBegin ( GL_POLYGON ) ; glNormal3d ( -0.850650808354, 0.0, 0.525731112119 ) ; glVertex3d ( -0.61803398875, 0.0, 1.61803398875 ) ; glVertex3d ( -1.0, 1.0, 1.0 ) ; glVertex3d ( -1.61803398875, 0.61803398875, 0.0 ) ; glVertex3d ( -1.61803398875, -0.61803398875, 0.0 ) ; glVertex3d ( -1.0, -1.0, 1.0 ) ; glEnd () ; glBegin ( GL_POLYGON ) ; glNormal3d ( 0.850650808354, 0.0, -0.525731112119 ) ; glVertex3d ( 0.61803398875, 0.0, -1.61803398875 ) ; glVertex3d ( 1.0, 1.0, -1.0 ) ; glVertex3d ( 1.61803398875, 0.61803398875, 0.0 ) ; glVertex3d ( 1.61803398875, -0.61803398875, 0.0 ) ; glVertex3d ( 1.0, -1.0, -1.0 ) ; glEnd () ; glBegin ( GL_POLYGON ) ; glNormal3d ( -0.850650808354, 0.0, -0.525731112119 ) ; glVertex3d ( -0.61803398875, 0.0, -1.61803398875 ) ; glVertex3d ( -1.0, -1.0, -1.0 ) ; glVertex3d ( -1.61803398875, -0.61803398875, 0.0 ) ; glVertex3d ( -1.61803398875, 0.61803398875, 0.0 ) ; glVertex3d ( -1.0, 1.0, -1.0 ) ; glEnd () ; glBegin ( GL_POLYGON ) ; glNormal3d ( 0.525731112119, 0.850650808354, 0.0 ) ; glVertex3d ( 1.61803398875, 0.61803398875, 0.0 ) ; glVertex3d ( 1.0, 1.0, -1.0 ) ; glVertex3d ( 0.0, 1.61803398875, -0.61803398875 ) ; glVertex3d ( 0.0, 1.61803398875, 0.61803398875 ) ; glVertex3d ( 1.0, 1.0, 1.0 ) ; glEnd () ; glBegin ( GL_POLYGON ) ; glNormal3d ( 0.525731112119, -0.850650808354, 0.0 ) ; glVertex3d ( 1.61803398875, -0.61803398875, 0.0 ) ; glVertex3d ( 1.0, -1.0, 1.0 ) ; glVertex3d ( 0.0, -1.61803398875, 0.61803398875 ) ; glVertex3d ( 0.0, -1.61803398875, -0.61803398875 ) ; glVertex3d ( 1.0, -1.0, -1.0 ) ; glEnd () ; glBegin ( GL_POLYGON ) ; glNormal3d ( -0.525731112119, 0.850650808354, 0.0 ) ; glVertex3d ( -1.61803398875, 0.61803398875, 0.0 ) ; glVertex3d ( -1.0, 1.0, 1.0 ) ; glVertex3d ( 0.0, 1.61803398875, 0.61803398875 ) ; glVertex3d ( 0.0, 1.61803398875, -0.61803398875 ) ; glVertex3d ( -1.0, 1.0, -1.0 ) ; glEnd () ; glBegin ( GL_POLYGON ) ; glNormal3d ( -0.525731112119, -0.850650808354, 0.0 ) ; glVertex3d ( -1.61803398875, -0.61803398875, 0.0 ) ; glVertex3d ( -1.0, -1.0, -1.0 ) ; glVertex3d ( 0.0, -1.61803398875, -0.61803398875 ) ; glVertex3d ( 0.0, -1.61803398875, 0.61803398875 ) ; glVertex3d ( -1.0, -1.0, 1.0 ) ; glEnd () ; } /* * */ void glutWireOctahedron( void ) { #define RADIUS 1.0f glBegin( GL_LINE_LOOP ); glNormal3d( 0.577350269189, 0.577350269189, 0.577350269189); glVertex3d( RADIUS, 0.0, 0.0 ); glVertex3d( 0.0, RADIUS, 0.0 ); glVertex3d( 0.0, 0.0, RADIUS ); glNormal3d( 0.577350269189, 0.577350269189,-0.577350269189); glVertex3d( RADIUS, 0.0, 0.0 ); glVertex3d( 0.0, 0.0,-RADIUS ); glVertex3d( 0.0, RADIUS, 0.0 ); glNormal3d( 0.577350269189,-0.577350269189, 0.577350269189); glVertex3d( RADIUS, 0.0, 0.0 ); glVertex3d( 0.0, 0.0, RADIUS ); glVertex3d( 0.0,-RADIUS, 0.0 ); glNormal3d( 0.577350269189,-0.577350269189,-0.577350269189); glVertex3d( RADIUS, 0.0, 0.0 ); glVertex3d( 0.0,-RADIUS, 0.0 ); glVertex3d( 0.0, 0.0,-RADIUS ); glNormal3d(-0.577350269189, 0.577350269189, 0.577350269189); glVertex3d(-RADIUS, 0.0, 0.0 ); glVertex3d( 0.0, 0.0, RADIUS ); glVertex3d( 0.0, RADIUS, 0.0 ); glNormal3d(-0.577350269189, 0.577350269189,-0.577350269189); glVertex3d(-RADIUS, 0.0, 0.0 ); glVertex3d( 0.0, RADIUS, 0.0 ); glVertex3d( 0.0, 0.0,-RADIUS ); glNormal3d(-0.577350269189,-0.577350269189, 0.577350269189); glVertex3d(-RADIUS, 0.0, 0.0 ); glVertex3d( 0.0,-RADIUS, 0.0 ); glVertex3d( 0.0, 0.0, RADIUS ); glNormal3d(-0.577350269189,-0.577350269189,-0.577350269189); glVertex3d(-RADIUS, 0.0, 0.0 ); glVertex3d( 0.0, 0.0,-RADIUS ); glVertex3d( 0.0,-RADIUS, 0.0 ); glEnd(); #undef RADIUS } /* * */ void glutSolidOctahedron( void ) { #define RADIUS 1.0f glBegin( GL_TRIANGLES ); glNormal3d( 0.577350269189, 0.577350269189, 0.577350269189); glVertex3d( RADIUS, 0.0, 0.0 ); glVertex3d( 0.0, RADIUS, 0.0 ); glVertex3d( 0.0, 0.0, RADIUS ); glNormal3d( 0.577350269189, 0.577350269189,-0.577350269189); glVertex3d( RADIUS, 0.0, 0.0 ); glVertex3d( 0.0, 0.0,-RADIUS ); glVertex3d( 0.0, RADIUS, 0.0 ); glNormal3d( 0.577350269189,-0.577350269189, 0.577350269189); glVertex3d( RADIUS, 0.0, 0.0 ); glVertex3d( 0.0, 0.0, RADIUS ); glVertex3d( 0.0,-RADIUS, 0.0 ); glNormal3d( 0.577350269189,-0.577350269189,-0.577350269189); glVertex3d( RADIUS, 0.0, 0.0 ); glVertex3d( 0.0,-RADIUS, 0.0 ); glVertex3d( 0.0, 0.0,-RADIUS ); glNormal3d(-0.577350269189, 0.577350269189, 0.577350269189); glVertex3d(-RADIUS, 0.0, 0.0 ); glVertex3d( 0.0, 0.0, RADIUS ); glVertex3d( 0.0, RADIUS, 0.0 ); glNormal3d(-0.577350269189, 0.577350269189,-0.577350269189); glVertex3d(-RADIUS, 0.0, 0.0 ); glVertex3d( 0.0, RADIUS, 0.0 ); glVertex3d( 0.0, 0.0,-RADIUS ); glNormal3d(-0.577350269189,-0.577350269189, 0.577350269189); glVertex3d(-RADIUS, 0.0, 0.0 ); glVertex3d( 0.0,-RADIUS, 0.0 ); glVertex3d( 0.0, 0.0, RADIUS ); glNormal3d(-0.577350269189,-0.577350269189,-0.577350269189); glVertex3d(-RADIUS, 0.0, 0.0 ); glVertex3d( 0.0, 0.0,-RADIUS ); glVertex3d( 0.0,-RADIUS, 0.0 ); glEnd(); #undef RADIUS } /* Magic Numbers: r0 = ( 1, 0, 0 ) * r1 = ( -1/3, 2 sqrt(2) / 3, 0 ) * r2 = ( -1/3, -sqrt(2) / 3, sqrt(6) / 3 ) * r3 = ( -1/3, -sqrt(2) / 3, -sqrt(6) / 3 ) * |r0| = |r1| = |r2| = |r3| = 1 * Distance between any two points is 2 sqrt(6) / 3 * * Normals: The unit normals are simply the negative of the coordinates of the point not on the surface. */ #define NUM_TETR_FACES 4 static GLdouble tet_r[4][3] = { { 1.0, 0.0, 0.0 }, { -0.333333333333, 0.942809041582, 0.0 }, { -0.333333333333, -0.471404520791, 0.816496580928 }, { -0.333333333333, -0.471404520791, -0.816496580928 } } ; static GLint tet_i[4][3] = /* Vertex indices */ { { 1, 3, 2 }, { 0, 2, 3 }, { 0, 3, 1 }, { 0, 1, 2 } } ; /* * */ void glutWireTetrahedron( void ) { glBegin( GL_LINE_LOOP ) ; glNormal3d ( -tet_r[0][0], -tet_r[0][1], -tet_r[0][2] ) ; glVertex3dv ( tet_r[1] ) ; glVertex3dv ( tet_r[3] ) ; glVertex3dv ( tet_r[2] ) ; glNormal3d ( -tet_r[1][0], -tet_r[1][1], -tet_r[1][2] ) ; glVertex3dv ( tet_r[0] ) ; glVertex3dv ( tet_r[2] ) ; glVertex3dv ( tet_r[3] ) ; glNormal3d ( -tet_r[2][0], -tet_r[2][1], -tet_r[2][2] ) ; glVertex3dv ( tet_r[0] ) ; glVertex3dv ( tet_r[3] ) ; glVertex3dv ( tet_r[1] ) ; glNormal3d ( -tet_r[3][0], -tet_r[3][1], -tet_r[3][2] ) ; glVertex3dv ( tet_r[0] ) ; glVertex3dv ( tet_r[1] ) ; glVertex3dv ( tet_r[2] ) ; glEnd() ; } /* * */ void glutSolidTetrahedron( void ) { glBegin( GL_TRIANGLES ) ; glNormal3d ( -tet_r[0][0], -tet_r[0][1], -tet_r[0][2] ) ; glVertex3dv ( tet_r[1] ) ; glVertex3dv ( tet_r[3] ) ; glVertex3dv ( tet_r[2] ) ; glNormal3d ( -tet_r[1][0], -tet_r[1][1], -tet_r[1][2] ) ; glVertex3dv ( tet_r[0] ) ; glVertex3dv ( tet_r[2] ) ; glVertex3dv ( tet_r[3] ) ; glNormal3d ( -tet_r[2][0], -tet_r[2][1], -tet_r[2][2] ) ; glVertex3dv ( tet_r[0] ) ; glVertex3dv ( tet_r[3] ) ; glVertex3dv ( tet_r[1] ) ; glNormal3d ( -tet_r[3][0], -tet_r[3][1], -tet_r[3][2] ) ; glVertex3dv ( tet_r[0] ) ; glVertex3dv ( tet_r[1] ) ; glVertex3dv ( tet_r[2] ) ; glEnd() ; } /* * */ double icos_r[12][3] = { { 1.0, 0.0, 0.0 }, { 0.447213595500, 0.894427191000, 0.0 }, { 0.447213595500, 0.276393202252, 0.850650808354 }, { 0.447213595500, -0.723606797748, 0.525731112119 }, { 0.447213595500, -0.723606797748, -0.525731112119 }, { 0.447213595500, 0.276393202252, -0.850650808354 }, { -0.447213595500, -0.894427191000, 0.0 }, { -0.447213595500, -0.276393202252, 0.850650808354 }, { -0.447213595500, 0.723606797748, 0.525731112119 }, { -0.447213595500, 0.723606797748, -0.525731112119 }, { -0.447213595500, -0.276393202252, -0.850650808354 }, { -1.0, 0.0, 0.0 } } ; int icos_v [20][3] = { { 0, 1, 2 }, { 0, 2, 3 }, { 0, 3, 4 }, { 0, 4, 5 }, { 0, 5, 1 }, { 1, 8, 2 }, { 2, 7, 3 }, { 3, 6, 4 }, { 4, 10, 5 }, { 5, 9, 1 }, { 1, 9, 8 }, { 2, 8, 7 }, { 3, 7, 6 }, { 4, 6, 10 }, { 5, 10, 9 }, { 11, 9, 10 }, { 11, 8, 9 }, { 11, 7, 8 }, { 11, 6, 7 }, { 11, 10, 6 } } ; void glutWireIcosahedron( void ) { int i ; for ( i = 0; i < 20; i++ ) { double normal[3] ; normal[0] = ( icos_r[icos_v[i][1]][1] - icos_r[icos_v[i][0]][1] ) * ( icos_r[icos_v[i][2]][2] - icos_r[icos_v[i][0]][2] ) - ( icos_r[icos_v[i][1]][2] - icos_r[icos_v[i][0]][2] ) * ( icos_r[icos_v[i][2]][1] - icos_r[icos_v[i][0]][1] ) ; normal[1] = ( icos_r[icos_v[i][1]][2] - icos_r[icos_v[i][0]][2] ) * ( icos_r[icos_v[i][2]][0] - icos_r[icos_v[i][0]][0] ) - ( icos_r[icos_v[i][1]][0] - icos_r[icos_v[i][0]][0] ) * ( icos_r[icos_v[i][2]][2] - icos_r[icos_v[i][0]][2] ) ; normal[2] = ( icos_r[icos_v[i][1]][0] - icos_r[icos_v[i][0]][0] ) * ( icos_r[icos_v[i][2]][1] - icos_r[icos_v[i][0]][1] ) - ( icos_r[icos_v[i][1]][1] - icos_r[icos_v[i][0]][1] ) * ( icos_r[icos_v[i][2]][0] - icos_r[icos_v[i][0]][0] ) ; glBegin ( GL_LINE_LOOP ) ; glNormal3dv ( normal ) ; glVertex3dv ( icos_r[icos_v[i][0]] ) ; glVertex3dv ( icos_r[icos_v[i][1]] ) ; glVertex3dv ( icos_r[icos_v[i][2]] ) ; glEnd () ; } } /* * */ void glutSolidIcosahedron( void ) { int i ; glBegin ( GL_TRIANGLES ) ; for ( i = 0; i < 20; i++ ) { double normal[3] ; normal[0] = ( icos_r[icos_v[i][1]][1] - icos_r[icos_v[i][0]][1] ) * ( icos_r[icos_v[i][2]][2] - icos_r[icos_v[i][0]][2] ) - ( icos_r[icos_v[i][1]][2] - icos_r[icos_v[i][0]][2] ) * ( icos_r[icos_v[i][2]][1] - icos_r[icos_v[i][0]][1] ) ; normal[1] = ( icos_r[icos_v[i][1]][2] - icos_r[icos_v[i][0]][2] ) * ( icos_r[icos_v[i][2]][0] - icos_r[icos_v[i][0]][0] ) - ( icos_r[icos_v[i][1]][0] - icos_r[icos_v[i][0]][0] ) * ( icos_r[icos_v[i][2]][2] - icos_r[icos_v[i][0]][2] ) ; normal[2] = ( icos_r[icos_v[i][1]][0] - icos_r[icos_v[i][0]][0] ) * ( icos_r[icos_v[i][2]][1] - icos_r[icos_v[i][0]][1] ) - ( icos_r[icos_v[i][1]][1] - icos_r[icos_v[i][0]][1] ) * ( icos_r[icos_v[i][2]][0] - icos_r[icos_v[i][0]][0] ) ; glNormal3dv ( normal ) ; glVertex3dv ( icos_r[icos_v[i][0]] ) ; glVertex3dv ( icos_r[icos_v[i][1]] ) ; glVertex3dv ( icos_r[icos_v[i][2]] ) ; } glEnd () ; } /* * */ double rdod_r[14][3] = { { 0.0, 0.0, 1.0 }, { 0.707106781187, 0.000000000000, 0.5 }, { 0.000000000000, 0.707106781187, 0.5 }, { -0.707106781187, 0.000000000000, 0.5 }, { 0.000000000000, -0.707106781187, 0.5 }, { 0.707106781187, 0.707106781187, 0.0 }, { -0.707106781187, 0.707106781187, 0.0 }, { -0.707106781187, -0.707106781187, 0.0 }, { 0.707106781187, -0.707106781187, 0.0 }, { 0.707106781187, 0.000000000000, -0.5 }, { 0.000000000000, 0.707106781187, -0.5 }, { -0.707106781187, 0.000000000000, -0.5 }, { 0.000000000000, -0.707106781187, -0.5 }, { 0.0, 0.0, -1.0 } } ; int rdod_v [12][4] = { { 0, 1, 5, 2 }, { 0, 2, 6, 3 }, { 0, 3, 7, 4 }, { 0, 4, 8, 1 }, { 5, 10, 6, 2 }, { 6, 11, 7, 3 }, { 7, 12, 8, 4 }, { 8, 9, 5, 1 }, { 5, 9, 13, 10 }, { 6, 10, 13, 11 }, { 7, 11, 13, 12 }, { 8, 12, 13, 9 } } ; double rdod_n[12][3] = { { 0.353553390594, 0.353553390594, 0.5 }, { -0.353553390594, 0.353553390594, 0.5 }, { -0.353553390594, -0.353553390594, 0.5 }, { 0.353553390594, -0.353553390594, 0.5 }, { 0.000000000000, 1.000000000000, 0.0 }, { -1.000000000000, 0.000000000000, 0.0 }, { 0.000000000000, -1.000000000000, 0.0 }, { 1.000000000000, 0.000000000000, 0.0 }, { 0.353553390594, 0.353553390594, -0.5 }, { -0.353553390594, 0.353553390594, -0.5 }, { -0.353553390594, -0.353553390594, -0.5 }, { 0.353553390594, -0.353553390594, -0.5 } } ; void glutWireRhombicDodecahedron( void ) { int i ; for ( i = 0; i < 12; i++ ) { glBegin ( GL_LINE_LOOP ) ; glNormal3dv ( rdod_n[i] ) ; glVertex3dv ( rdod_r[rdod_v[i][0]] ) ; glVertex3dv ( rdod_r[rdod_v[i][1]] ) ; glVertex3dv ( rdod_r[rdod_v[i][2]] ) ; glVertex3dv ( rdod_r[rdod_v[i][3]] ) ; glEnd () ; } } /* * */ void glutSolidRhombicDodecahedron( void ) { int i ; glBegin ( GL_QUADS ) ; for ( i = 0; i < 12; i++ ) { glNormal3dv ( rdod_n[i] ) ; glVertex3dv ( rdod_r[rdod_v[i][0]] ) ; glVertex3dv ( rdod_r[rdod_v[i][1]] ) ; glVertex3dv ( rdod_r[rdod_v[i][2]] ) ; glVertex3dv ( rdod_r[rdod_v[i][3]] ) ; } glEnd () ; } void glutWireSierpinskiSponge ( int num_levels, GLdouble offset[3], GLdouble scale ) { int i, j ; if ( num_levels == 0 ) { for ( i = 0 ; i < NUM_TETR_FACES ; i++ ) { glBegin ( GL_LINE_LOOP ) ; glNormal3d ( -tet_r[i][0], -tet_r[i][1], -tet_r[i][2] ) ; for ( j = 0; j < 3; j++ ) { double x = offset[0] + scale * tet_r[tet_i[i][j]][0] ; double y = offset[1] + scale * tet_r[tet_i[i][j]][1] ; double z = offset[2] + scale * tet_r[tet_i[i][j]][2] ; glVertex3d ( x, y, z ) ; } glEnd () ; } } else { GLdouble local_offset[3] ; /* Use a local variable to avoid buildup of roundoff errors */ num_levels -- ; scale /= 2.0 ; for ( i = 0 ; i < NUM_TETR_FACES ; i++ ) { local_offset[0] = offset[0] + scale * tet_r[i][0] ; local_offset[1] = offset[1] + scale * tet_r[i][1] ; local_offset[2] = offset[2] + scale * tet_r[i][2] ; glutWireSierpinskiSponge ( num_levels, local_offset, scale ) ; } } } void glutSolidSierpinskiSponge ( int num_levels, GLdouble offset[3], GLdouble scale ) { int i, j ; if ( num_levels == 0 ) { glBegin ( GL_TRIANGLES ) ; for ( i = 0 ; i < NUM_TETR_FACES ; i++ ) { glNormal3d ( -tet_r[i][0], -tet_r[i][1], -tet_r[i][2] ) ; for ( j = 0; j < 3; j++ ) { double x = offset[0] + scale * tet_r[tet_i[i][j]][0] ; double y = offset[1] + scale * tet_r[tet_i[i][j]][1] ; double z = offset[2] + scale * tet_r[tet_i[i][j]][2] ; glVertex3d ( x, y, z ) ; } } glEnd () ; } else { GLdouble local_offset[3] ; /* Use a local variable to avoid buildup of roundoff errors */ num_levels -- ; scale /= 2.0 ; for ( i = 0 ; i < NUM_TETR_FACES ; i++ ) { local_offset[0] = offset[0] + scale * tet_r[i][0] ; local_offset[1] = offset[1] + scale * tet_r[i][1] ; local_offset[2] = offset[2] + scale * tet_r[i][2] ; glutSolidSierpinskiSponge ( num_levels, local_offset, scale ) ; } } } /*** END OF FILE ***/