#include <stdlib.h> #include <math.h> #include <GL/gl.h> #include "glu.h" void drawTorus(float rc, int numc, float rt, int numt) { int i, j, k; double s, t; double x, y, z; double pi, twopi; pi = 3.14159265358979323846; twopi = 2 * pi; for (i = 0; i < numc; i++) { glBegin(GL_QUAD_STRIP); for (j = 0; j <= numt; j++) { for (k = 1; k >= 0; k--) { s = (i + k) % numc + 0.5; t = j % numt; x = cos(t*twopi/numt) * cos(s*twopi/numc); y = sin(t*twopi/numt) * cos(s*twopi/numc); z = sin(s*twopi/numc); glNormal3f(x, y, z); x = (rt + rc * cos(s*twopi/numc)) * cos(t*twopi/numt); y = (rt + rc * cos(s*twopi/numc)) * sin(t*twopi/numt); z = rc * sin(s*twopi/numc); glVertex3f(x, y, z); } } glEnd(); } } static void normal3f( GLfloat x, GLfloat y, GLfloat z ) { GLdouble mag; mag = sqrt( x*x + y*y + z*z ); if (mag>0.00001F) { x /= mag; y /= mag; z /= mag; } glNormal3f( x, y, z ); } void gluPerspective( GLdouble fovy, GLdouble aspect, GLdouble zNear, GLdouble zFar ) { GLdouble xmin, xmax, ymin, ymax; ymax = zNear * tan( fovy * M_PI / 360.0 ); ymin = -ymax; xmin = ymin * aspect; xmax = ymax * aspect; glFrustum( xmin, xmax, ymin, ymax, zNear, zFar ); } GLUquadricObj *gluNewQuadric(void) { return NULL; } void gluQuadricDrawStyle(GLUquadricObj *obj, int style) { } void gluCylinder( GLUquadricObj *qobj, GLdouble baseRadius, GLdouble topRadius, GLdouble height, GLint slices, GLint stacks ) { GLdouble da, r, dr, dz; GLfloat z, nz, nsign; GLint i, j; GLfloat du = 1.0 / slices; GLfloat dv = 1.0 / stacks; GLfloat tcx = 0.0, tcy = 0.0; nsign = 1.0; da = 2.0*M_PI / slices; dr = (topRadius-baseRadius) / stacks; dz = height / stacks; nz = (baseRadius-topRadius) / height; /* Z component of normal vectors */ for (i=0;i<slices;i++) { GLfloat x1 = -sin(i*da); GLfloat y1 = cos(i*da); GLfloat x2 = -sin((i+1)*da); GLfloat y2 = cos((i+1)*da); z = 0.0; r = baseRadius; tcy = 0.0; glBegin( GL_QUAD_STRIP ); for (j=0;j<=stacks;j++) { if (nsign==1.0) { normal3f( x1*nsign, y1*nsign, nz*nsign ); glTexCoord2f(tcx, tcy); glVertex3f( x1*r, y1*r, z ); normal3f( x2*nsign, y2*nsign, nz*nsign ); glTexCoord2f(tcx+du, tcy); glVertex3f( x2*r, y2*r, z ); } else { normal3f( x2*nsign, y2*nsign, nz*nsign ); glTexCoord2f(tcx, tcy); glVertex3f( x2*r, y2*r, z ); normal3f( x1*nsign, y1*nsign, nz*nsign ); glTexCoord2f(tcx+du, tcy); glVertex3f( x1*r, y1*r, z ); } z += dz; r += dr; tcy += dv; } glEnd(); tcx += du; } } /* Disk (adapted from Mesa) */ void gluDisk( GLUquadricObj *qobj, GLdouble innerRadius, GLdouble outerRadius, GLint slices, GLint loops ) { GLdouble a, da; GLfloat dr; GLfloat r1, r2, dtc; GLint s, l; GLfloat sa,ca; /* Normal vectors */ glNormal3f( 0.0, 0.0, +1.0 ); da = 2.0*M_PI / slices; dr = (outerRadius-innerRadius) / (GLfloat) loops; /* texture of a gluDisk is a cut out of the texture unit square */ /* x, y in [-outerRadius, +outerRadius]; s, t in [0, 1] (linear mapping) */ dtc = 2.0f * outerRadius; r1 = innerRadius; for (l=0;l<loops;l++) { r2 = r1 + dr; glBegin( GL_QUAD_STRIP ); for (s=0;s<=slices;s++) { if (s==slices) a = 0.0; else a = s * da; sa = sin(a); ca = cos(a); glTexCoord2f(0.5+sa*r2/dtc,0.5+ca*r2/dtc); glVertex2f( r2*sa, r2*ca ); glTexCoord2f(0.5+sa*r1/dtc,0.5+ca*r1/dtc); glVertex2f( r1*sa, r1*ca ); } glEnd(); r1 = r2; } } /* * Sph�re (adapted from Mesa) */ void gluSphere(GLUquadricObj *qobj, float radius,int slices,int stacks) { float rho, drho, theta, dtheta; float x, y, z; float s, t, ds, dt; int i, j, imin, imax; int normals; float nsign; normals=1; nsign=1; drho = M_PI / (float) stacks; dtheta = 2.0 * M_PI / (float) slices; /* draw +Z end as a triangle fan */ glBegin( GL_TRIANGLE_FAN ); glNormal3f( 0.0, 0.0, 1.0 ); glTexCoord2f(0.5,0.0); glVertex3f( 0.0, 0.0, nsign * radius ); for (j=0;j<=slices;j++) { theta = (j==slices) ? 0.0 : j * dtheta; x = -sin(theta) * sin(drho); y = cos(theta) * sin(drho); z = nsign * cos(drho); if (normals) glNormal3f( x*nsign, y*nsign, z*nsign ); glVertex3f( x*radius, y*radius, z*radius ); } glEnd(); ds = 1.0 / slices; dt = 1.0 / stacks; t = 1.0; /* because loop now runs from 0 */ if (1) { imin = 0; imax = stacks; } else { imin = 1; imax = stacks-1; } /* draw intermediate stacks as quad strips */ for (i=imin;i<imax;i++) { rho = i * drho; glBegin( GL_QUAD_STRIP ); s = 0.0; for (j=0;j<=slices;j++) { theta = (j==slices) ? 0.0 : j * dtheta; x = -sin(theta) * sin(rho); y = cos(theta) * sin(rho); z = nsign * cos(rho); if (normals) glNormal3f( x*nsign, y*nsign, z*nsign ); glTexCoord2f(s,1-t); glVertex3f( x*radius, y*radius, z*radius ); x = -sin(theta) * sin(rho+drho); y = cos(theta) * sin(rho+drho); z = nsign * cos(rho+drho); if (normals) glNormal3f( x*nsign, y*nsign, z*nsign ); glTexCoord2f(s,1-(t-dt)); s += ds; glVertex3f( x*radius, y*radius, z*radius ); } glEnd(); t -= dt; } /* draw -Z end as a triangle fan */ glBegin( GL_TRIANGLE_FAN ); glNormal3f( 0.0, 0.0, -1.0 ); glTexCoord2f(0.5,1.0); glVertex3f( 0.0, 0.0, -radius*nsign ); rho = M_PI - drho; s = 1.0; t = dt; for (j=slices;j>=0;j--) { theta = (j==slices) ? 0.0 : j * dtheta; x = -sin(theta) * sin(rho); y = cos(theta) * sin(rho); z = nsign * cos(rho); if (normals) glNormal3f( x*nsign, y*nsign, z*nsign ); glTexCoord2f(s,1-t); s -= ds; glVertex3f( x*radius, y*radius, z*radius ); } glEnd(); }