0,0 → 1,343 |
#include <stdlib.h> |
#include <math.h> |
#include <GL/gl.h> |
#include <GL/glu.h> |
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void drawTorus(float rc, int numc, float rt, int numt) |
{ |
int i, j, k; |
double s, t; |
double x, y, z; |
double pi, twopi; |
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pi = 3.14159265358979323846; |
twopi = 2 * pi; |
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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; |
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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); |
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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(); |
} |
} |
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static void normal3f( GLfloat x, GLfloat y, GLfloat z ) |
{ |
GLdouble mag; |
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mag = sqrt( x*x + y*y + z*z ); |
if (mag>0.00001F) { |
x /= mag; |
y /= mag; |
z /= mag; |
} |
glNormal3f( x, y, z ); |
} |
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void gluPerspective( GLdouble fovy, GLdouble aspect, |
GLdouble zNear, GLdouble zFar ) |
{ |
GLdouble xmin, xmax, ymin, ymax; |
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ymax = zNear * tan( fovy * M_PI / 360.0 ); |
ymin = -ymax; |
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xmin = ymin * aspect; |
xmax = ymax * aspect; |
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glFrustum( xmin, xmax, ymin, ymax, zNear, zFar ); |
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} |
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void |
gluLookAt(GLdouble eyex, GLdouble eyey, GLdouble eyez, |
GLdouble centerx, GLdouble centery, GLdouble centerz, |
GLdouble upx, GLdouble upy, GLdouble upz) |
{ |
GLfloat m[16]; |
GLdouble x[3], y[3], z[3]; |
GLdouble mag; |
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/* Make rotation matrix */ |
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/* Z vector */ |
z[0] = eyex - centerx; |
z[1] = eyey - centery; |
z[2] = eyez - centerz; |
mag = sqrt(z[0] * z[0] + z[1] * z[1] + z[2] * z[2]); |
if (mag) { /* mpichler, 19950515 */ |
z[0] /= mag; |
z[1] /= mag; |
z[2] /= mag; |
} |
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/* Y vector */ |
y[0] = upx; |
y[1] = upy; |
y[2] = upz; |
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/* X vector = Y cross Z */ |
x[0] = y[1] * z[2] - y[2] * z[1]; |
x[1] = -y[0] * z[2] + y[2] * z[0]; |
x[2] = y[0] * z[1] - y[1] * z[0]; |
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/* Recompute Y = Z cross X */ |
y[0] = z[1] * x[2] - z[2] * x[1]; |
y[1] = -z[0] * x[2] + z[2] * x[0]; |
y[2] = z[0] * x[1] - z[1] * x[0]; |
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/* mpichler, 19950515 */ |
/* cross product gives area of parallelogram, which is < 1.0 for |
* non-perpendicular unit-length vectors; so normalize x, y here |
*/ |
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mag = sqrt(x[0] * x[0] + x[1] * x[1] + x[2] * x[2]); |
if (mag) { |
x[0] /= mag; |
x[1] /= mag; |
x[2] /= mag; |
} |
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mag = sqrt(y[0] * y[0] + y[1] * y[1] + y[2] * y[2]); |
if (mag) { |
y[0] /= mag; |
y[1] /= mag; |
y[2] /= mag; |
} |
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#define M(row,col) m[col*4+row] |
M(0, 0) = x[0]; |
M(0, 1) = x[1]; |
M(0, 2) = x[2]; |
M(0, 3) = 0.0; |
M(1, 0) = y[0]; |
M(1, 1) = y[1]; |
M(1, 2) = y[2]; |
M(1, 3) = 0.0; |
M(2, 0) = z[0]; |
M(2, 1) = z[1]; |
M(2, 2) = z[2]; |
M(2, 3) = 0.0; |
M(3, 0) = 0.0; |
M(3, 1) = 0.0; |
M(3, 2) = 0.0; |
M(3, 3) = 1.0; |
#undef M |
glMultMatrixf(m); |
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/* Translate Eye to Origin */ |
glTranslatef(-eyex, -eyey, -eyez); |
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} |
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GLUquadricObj *gluNewQuadric(void) |
{ |
return NULL; |
} |
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void gluQuadricDrawStyle(GLUquadricObj *obj, int style) |
{ |
} |
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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; |
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nsign = 1.0; |
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da = 2.0*M_PI / slices; |
dr = (topRadius-baseRadius) / stacks; |
dz = height / stacks; |
nz = (baseRadius-topRadius) / height; /* Z component of normal vectors */ |
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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; |
} |
} |
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/* Disk (adapted from Mesa) */ |
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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; |
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/* Normal vectors */ |
glNormal3f( 0.0, 0.0, +1.0 ); |
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da = 2.0*M_PI / slices; |
dr = (outerRadius-innerRadius) / (GLfloat) loops; |
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/* 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; |
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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; |
} |
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} |
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/* |
* Sphere (adapted from Mesa) |
*/ |
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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; |
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normals=1; |
nsign=1; |
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drho = M_PI / (float) stacks; |
dtheta = 2.0 * M_PI / (float) slices; |
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/* 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(); |
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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; |
} |
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/* 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; |
} |
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/* 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(); |
} |