1 /* aux2glut conversion Copyright (c) Mark J. Kilgard, 1994, 1995 */
2 
3 /**
4  * (c) Copyright 1993, Silicon Graphics, Inc.
5  * ALL RIGHTS RESERVED
6  * Permission to use, copy, modify, and distribute this software for
7  * any purpose and without fee is hereby granted, provided that the above
8  * copyright notice appear in all copies and that both the copyright notice
9  * and this permission notice appear in supporting documentation, and that
10  * the name of Silicon Graphics, Inc. not be used in advertising
11  * or publicity pertaining to distribution of the software without specific,
12  * written prior permission.
13  *
14  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS"
15  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,
16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR
17  * FITNESS FOR A PARTICULAR PURPOSE.  IN NO EVENT SHALL SILICON
18  * GRAPHICS, INC.  BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,
19  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY
20  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,
21  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF
22  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC.  HAS BEEN
23  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON
24  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE
25  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.
26  *
27  * US Government Users Restricted Rights
28  * Use, duplication, or disclosure by the Government is subject to
29  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph
30  * (c)(1)(ii) of the Rights in Technical Data and Computer Software
31  * clause at DFARS 252.227-7013 and/or in similar or successor
32  * clauses in the FAR or the DOD or NASA FAR Supplement.
33  * Unpublished-- rights reserved under the copyright laws of the
34  * United States.  Contractor/manufacturer is Silicon Graphics,
35  * Inc., 2011 N.  Shoreline Blvd., Mountain View, CA 94039-7311.
36  *
37  * OpenGL(TM) is a trademark of Silicon Graphics, Inc.
38  */
39 /**
40  *  surface.c
41  *  This program draws a NURBS surface in the shape of a
42  *  symmetrical hill.
43  */
44 #include <stdlib.h>
45 #include "glut_wrap.h"
46 
47 GLfloat ctlpoints[4][4][3];
48 int showPoints = 0;
49 
50 GLUnurbsObj *theNurb;
51 
52 /*
53  *  Initializes the control points of the surface to a small hill.
54  *  The control points range from -3 to +3 in x, y, and z
55  */
init_surface(void)56 static void init_surface(void)
57 {
58     int u, v;
59     for (u = 0; u < 4; u++) {
60 	for (v = 0; v < 4; v++) {
61 	    ctlpoints[u][v][0] = 2.0*((GLfloat)u - 1.5);
62 	    ctlpoints[u][v][1] = 2.0*((GLfloat)v - 1.5);
63 
64 	    if ( (u == 1 || u == 2) && (v == 1 || v == 2))
65 		ctlpoints[u][v][2] = 7.0;
66 	    else
67 		ctlpoints[u][v][2] = -3.0;
68 	}
69     }
70 }
71 
72 /*  Initialize material property and depth buffer.
73  */
myinit(void)74 static void myinit(void)
75 {
76     GLfloat mat_diffuse[] = { 0.7, 0.7, 0.7, 1.0 };
77     GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };
78     GLfloat mat_shininess[] = { 100.0 };
79 
80     glClearColor (0.0, 0.0, 0.0, 1.0);
81     glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
82     glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
83     glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess);
84 
85     glEnable(GL_LIGHTING);
86     glEnable(GL_LIGHT0);
87     glDepthFunc(GL_LESS);
88     glEnable(GL_DEPTH_TEST);
89     glEnable(GL_AUTO_NORMAL);
90     glEnable(GL_NORMALIZE);
91 
92     init_surface();
93 
94     theNurb = gluNewNurbsRenderer();
95     gluNurbsProperty(theNurb, GLU_SAMPLING_TOLERANCE, 25.0);
96     gluNurbsProperty(theNurb, GLU_DISPLAY_MODE, GLU_FILL);
97 
98     glMatrixMode(GL_MODELVIEW);
99     glLoadIdentity();
100     glTranslatef (0.0, 0.0, -5.0);
101 }
102 
display(void)103 static void display(void)
104 {
105     GLfloat knots[8] = {0.0, 0.0, 0.0, 0.0, 1.0, 1.0, 1.0, 1.0};
106     int i, j;
107 
108     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
109 
110     glPushMatrix();
111     glRotatef(330.0, 1.,0.,0.);
112     glScalef (0.25, 0.25, 0.25);
113 
114     gluBeginSurface(theNurb);
115     gluNurbsSurface(theNurb,
116 	    8, knots,
117 	    8, knots,
118 	    4 * 3,
119 	    3,
120 	    &ctlpoints[0][0][0],
121 	    4, 4,
122 	    GL_MAP2_VERTEX_3);
123     gluEndSurface(theNurb);
124 
125     if(showPoints) {
126     glPointSize(5.0);
127     glDisable(GL_LIGHTING);
128     glColor3f(1.0, 1.0, 0.0);
129     glBegin(GL_POINTS);
130     for(i=0;i<4;i++) {
131       for(j=0;j<4;j++) {
132 	glVertex3f(ctlpoints[i][j][0], ctlpoints[i][j][1], ctlpoints[i][j][2]);
133       }
134     }
135     glEnd();
136     glEnable(GL_LIGHTING);
137     }
138 
139     glPopMatrix();
140     glutSwapBuffers();
141 }
142 
reshape(int w,int h)143 static void reshape(int w, int h)
144 {
145     glViewport(0, 0, w, h);
146     glMatrixMode(GL_PROJECTION);
147     glLoadIdentity();
148     gluPerspective (45.0, (GLdouble)w/(GLdouble)h, 3.0, 8.0);
149 
150     glMatrixMode(GL_MODELVIEW);
151 }
152 
153 static void
menu(int value)154 menu(int value)
155 {
156     switch (value) {
157     case 0:
158     case 1:
159         showPoints = value;
160 	break;
161     case 2:
162         gluNurbsProperty(theNurb, GLU_DISPLAY_MODE, GLU_FILL);
163 	break;
164     case 3:
165         gluNurbsProperty(theNurb, GLU_DISPLAY_MODE, GLU_OUTLINE_POLYGON);
166 	break;
167     }
168     glutPostRedisplay();
169 }
170 
171 int down = 0, lastx;
172 
173 /* ARGSUSED1 */
174 static void
motion(int x,int y)175 motion(int x, int y)
176 {
177     if (down) {
178         glRotatef(lastx - x, 0, 1, 0);
179         lastx = x;
180         glutPostRedisplay();
181     }
182 }
183 
184 /* ARGSUSED3 */
185 static void
mouse(int button,int state,int x,int y)186 mouse(int button, int state, int x, int y)
187 {
188     if (button == GLUT_LEFT_BUTTON) {
189         if (state == GLUT_DOWN) {
190             lastx = x;
191             down = 1;
192         } else {
193             down = 0;
194         }
195     }
196 }
197 
198 static void
key(unsigned char k,int x,int y)199 key(unsigned char k, int x, int y)
200 {
201   switch (k) {
202   case 27:  /* Escape */
203     exit(0);
204     break;
205   default:
206     return;
207   }
208   glutPostRedisplay();
209 }
210 
211 /* Main Loop */
212 int
main(int argc,char ** argv)213 main(int argc, char** argv)
214 {
215     glutInit(&argc, argv);
216     glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGB);
217     glutCreateWindow(argv[0]);
218     myinit();
219     glutReshapeFunc(reshape);
220     glutDisplayFunc(display);
221     glutCreateMenu(menu);
222     glutAddMenuEntry("Show control points", 1);
223     glutAddMenuEntry("Hide control points", 0);
224     glutAddMenuEntry("Solid", 2);
225     glutAddMenuEntry("Wireframe", 3);
226     glutAttachMenu(GLUT_RIGHT_BUTTON);
227     glutMouseFunc(mouse);
228     glutMotionFunc(motion);
229     glutKeyboardFunc(key);
230     glutMainLoop();
231     return 0;             /* ANSI C requires main to return int. */
232 }
233