#include <stdlib.h>
#include <GL/glut.h>
#define S_NUMPOINTS 13
#define S_ORDER 3
#define S_NUMKNOTS (S_NUMPOINTS + S_ORDER)
#define T_NUMPOINTS 3
#define T_ORDER 3
#define T_NUMKNOTS (T_NUMPOINTS + T_ORDER)
#define SQRT2 1.41421356237309504880
GLfloat sknots[S_NUMKNOTS] =
{-1.0, -1.0, -1.0, 0.0, 1.0, 2.0, 3.0, 4.0,
4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 9.0, 9.0};
GLfloat tknots[T_NUMKNOTS] = {1.0, 1.0, 1.0, 2.0, 2.0, 2.0};
GLfloat ctlpoints[S_NUMPOINTS][T_NUMPOINTS][4] = {
{ {4.,2.,2.,1.},{4.,1.6,2.5,1.},{4.,2.,3.0,1.} },
{ {5.,4.,2.,1.},{5.,4.,2.5,1.},{5.,4.,3.0,1.} },
{ {6.,5.,2.,1.},{6.,5.,2.5,1.},{6.,5.,3.0,1.} },
{ {SQRT2*6.,SQRT2*6.,SQRT2*2.,SQRT2},
{SQRT2*6.,SQRT2*6.,SQRT2*2.5,SQRT2},
{SQRT2*6.,SQRT2*6.,SQRT2*3.0,SQRT2} },
{ {5.2,6.7,2.,1.},{5.2,6.7,2.5,1.},{5.2,6.7,3.0,1.} },
{ {SQRT2*4.,SQRT2*6.,SQRT2*2.,SQRT2},
{SQRT2*4.,SQRT2*6.,SQRT2*2.5,SQRT2},
{SQRT2*4.,SQRT2*6.,SQRT2*3.0,SQRT2} },
{ {4.,5.2,2.,1.},{4.,4.6,2.5,1.},{4.,5.2,3.0,1.} },
{ {SQRT2*4.,SQRT2*6.,SQRT2*2.,SQRT2},
{SQRT2*4.,SQRT2*6.,SQRT2*2.5,SQRT2},
{SQRT2*4.,SQRT2*6.,SQRT2*3.0,SQRT2} },
{ {2.8,6.7,2.,1.},{2.8,6.7,2.5,1.},{2.8,6.7,3.0,1.} },
{ {SQRT2*2.,SQRT2*6.,SQRT2*2.,SQRT2},
{SQRT2*2.,SQRT2*6.,SQRT2*2.5,SQRT2},
{SQRT2*2.,SQRT2*6.,SQRT2*3.0,SQRT2} },
{ {2.,5.,2.,1.},{2.,5.,2.5,1.},{2.,5.,3.0,1.} },
{ {3.,4.,2.,1.},{3.,4.,2.5,1.},{3.,4.,3.0,1.} },
{ {4.,2.,2.,1.},{4.,1.6,2.5,1.},{4.,2.,3.0,1.} }
};
GLUnurbsObj *theNurb;
void myinit(void)
{
GLfloat mat_ambient[] = { 1.0, 1.0, 1.0, 1.0 };
GLfloat mat_diffuse[] = { 1.0, 0.2, 1.0, 1.0 };
GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };
GLfloat mat_shininess[] = { 50.0 };
GLfloat light0_position[] = { 1.0, 0.1, 1.0, 0.0 };
GLfloat light1_position[] = { -1.0, 0.1, 1.0, 0.0 };
GLfloat lmodel_ambient[] = { 0.3, 0.3, 0.3, 1.0 };
glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);
glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess);
glLightfv(GL_LIGHT0, GL_POSITION, light0_position);
glLightfv(GL_LIGHT1, GL_POSITION, light1_position);
glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lmodel_ambient);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
glEnable(GL_LIGHT1);
glDepthFunc(GL_LESS);
glEnable(GL_DEPTH_TEST);
glEnable(GL_AUTO_NORMAL);
theNurb = gluNewNurbsRenderer();
gluNurbsProperty(theNurb, GLU_SAMPLING_TOLERANCE, 25.0);
gluNurbsProperty(theNurb, GLU_DISPLAY_MODE, GLU_FILL);
}
void display(void)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glPushMatrix();
glTranslatef (4., 4.5, 2.5);
glRotatef (220.0, 1., 0., 0.);
glRotatef (115.0, 0., 1., 0.);
glTranslatef (-4., -4.5, -2.5);
gluBeginSurface(theNurb);
gluNurbsSurface(theNurb,
S_NUMKNOTS, sknots,
T_NUMKNOTS, tknots,
4 * T_NUMPOINTS,
4,
&ctlpoints[0][0][0],
S_ORDER, T_ORDER,
GL_MAP2_VERTEX_4);
gluEndSurface(theNurb);
glPopMatrix();
glFlush();
}
void myReshape(int w, int h)
{
glViewport(0, 0, w, h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glFrustum(-1.0, 1.0, -1.5, 0.5, 0.8, 10.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
gluLookAt(7.0,4.5,4.0, 4.5,4.5,2.0, 6.0,-3.0,2.0);
}
static void
key(unsigned char k, int x, int y)
{
switch (k) {
case 27:
exit(0);
break;
default:
return;
}
glutPostRedisplay();
}
int main(int argc, char** argv)
{
glutInit(&argc, argv);
glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);
glutCreateWindow (argv[0]);
myinit();
glutReshapeFunc (myReshape);
glutDisplayFunc(display);
glutKeyboardFunc(key);
glutMainLoop();
return 0;
}