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Diffstat (limited to 'progs/redbook/bezcurve.c')
-rw-r--r-- | progs/redbook/bezcurve.c | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/progs/redbook/bezcurve.c b/progs/redbook/bezcurve.c new file mode 100644 index 00000000000..5dee440396b --- /dev/null +++ b/progs/redbook/bezcurve.c @@ -0,0 +1,114 @@ +/* + * Copyright (c) 1993-1997, Silicon Graphics, Inc. + * ALL RIGHTS RESERVED + * Permission to use, copy, modify, and distribute this software for + * any purpose and without fee is hereby granted, provided that the above + * copyright notice appear in all copies and that both the copyright notice + * and this permission notice appear in supporting documentation, and that + * the name of Silicon Graphics, Inc. not be used in advertising + * or publicity pertaining to distribution of the software without specific, + * written prior permission. + * + * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS" + * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE, + * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR + * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON + * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT, + * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY + * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION, + * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF + * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN + * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON + * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE + * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE. + * + * US Government Users Restricted Rights + * Use, duplication, or disclosure by the Government is subject to + * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph + * (c)(1)(ii) of the Rights in Technical Data and Computer Software + * clause at DFARS 252.227-7013 and/or in similar or successor + * clauses in the FAR or the DOD or NASA FAR Supplement. + * Unpublished-- rights reserved under the copyright laws of the + * United States. Contractor/manufacturer is Silicon Graphics, + * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311. + * + * OpenGL(R) is a registered trademark of Silicon Graphics, Inc. + */ + +/* bezcurve.c + * This program uses evaluators to draw a Bezier curve. + */ +#include <stdlib.h> +#include <GL/glut.h> + +GLfloat ctrlpoints[4][3] = { + { -4.0, -4.0, 0.0}, { -2.0, 4.0, 0.0}, + {2.0, -4.0, 0.0}, {4.0, 4.0, 0.0}}; + +void init(void) +{ + glClearColor(0.0, 0.0, 0.0, 0.0); + glShadeModel(GL_FLAT); + glMap1f(GL_MAP1_VERTEX_3, 0.0, 1.0, 3, 4, &ctrlpoints[0][0]); + glEnable(GL_MAP1_VERTEX_3); +} + +void display(void) +{ + int i; + + glClear(GL_COLOR_BUFFER_BIT); + glColor3f(1.0, 1.0, 1.0); + glBegin(GL_LINE_STRIP); + for (i = 0; i <= 30; i++) + glEvalCoord1f((GLfloat) i/30.0); + glEnd(); + /* The following code displays the control points as dots. */ + glPointSize(5.0); + glColor3f(1.0, 1.0, 0.0); + glBegin(GL_POINTS); + for (i = 0; i < 4; i++) + glVertex3fv(&ctrlpoints[i][0]); + glEnd(); + glFlush(); +} + +void reshape(int w, int h) +{ + glViewport(0, 0, (GLsizei) w, (GLsizei) h); + glMatrixMode(GL_PROJECTION); + glLoadIdentity(); + if (w <= h) + glOrtho(-5.0, 5.0, -5.0*(GLfloat)h/(GLfloat)w, + 5.0*(GLfloat)h/(GLfloat)w, -5.0, 5.0); + else + glOrtho(-5.0*(GLfloat)w/(GLfloat)h, + 5.0*(GLfloat)w/(GLfloat)h, -5.0, 5.0, -5.0, 5.0); + glMatrixMode(GL_MODELVIEW); + glLoadIdentity(); +} + +/* ARGSUSED1 */ +void keyboard(unsigned char key, int x, int y) +{ + switch (key) { + case 27: + exit(0); + break; + } +} + +int main(int argc, char** argv) +{ + glutInit(&argc, argv); + glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB); + glutInitWindowSize (500, 500); + glutInitWindowPosition (100, 100); + glutCreateWindow (argv[0]); + init (); + glutDisplayFunc(display); + glutReshapeFunc(reshape); + glutKeyboardFunc (keyboard); + glutMainLoop(); + return 0; +} |