diff options
Diffstat (limited to '3rdparty/tinygl-0.4-ugfx/examples/glu.c')
| -rw-r--r-- | 3rdparty/tinygl-0.4-ugfx/examples/glu.c | 261 |
1 files changed, 261 insertions, 0 deletions
diff --git a/3rdparty/tinygl-0.4-ugfx/examples/glu.c b/3rdparty/tinygl-0.4-ugfx/examples/glu.c new file mode 100644 index 00000000..38561e71 --- /dev/null +++ b/3rdparty/tinygl-0.4-ugfx/examples/glu.c @@ -0,0 +1,261 @@ +#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; + } + +} + +/* + * Sphère (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(); +} |