aaindex.c revision 32001f49 
1/*
2 * Copyright (c) 1993-1997, Silicon Graphics, Inc.
3 * ALL RIGHTS RESERVED
4 * Permission to use, copy, modify, and distribute this software for
5 * any purpose and without fee is hereby granted, provided that the above
6 * copyright notice appear in all copies and that both the copyright notice
7 * and this permission notice appear in supporting documentation, and that
8 * the name of Silicon Graphics, Inc. not be used in advertising
9 * or publicity pertaining to distribution of the software without specific,
10 * written prior permission.
11 *
12 * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS"
13 * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,
14 * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR
15 * FITNESS FOR A PARTICULAR PURPOSE.  IN NO EVENT SHALL SILICON
16 * GRAPHICS, INC.  BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,
17 * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY
18 * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,
19 * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF
20 * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC.  HAS BEEN
21 * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON
22 * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE
23 * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.
24 *
25 * US Government Users Restricted Rights
26 * Use, duplication, or disclosure by the Government is subject to
27 * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph
28 * (c)(1)(ii) of the Rights in Technical Data and Computer Software
29 * clause at DFARS 252.227-7013 and/or in similar or successor
30 * clauses in the FAR or the DOD or NASA FAR Supplement.
31 * Unpublished-- rights reserved under the copyright laws of the
32 * United States.  Contractor/manufacturer is Silicon Graphics,
33 * Inc., 2011 N.  Shoreline Blvd., Mountain View, CA 94039-7311.
34 *
35 * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.
36 */
37
38/*
39 *  aaindex.c
40 *  This program draws shows how to draw anti-aliased lines in color
41 *  index mode. It draws two diagonal lines to form an X; when 'r'
42 *  is typed in the window, the lines are rotated in opposite
43 *  directions.
44 */
45#include "glut_wrap.h"
46#include "stdlib.h"
47
48#define RAMPSIZE 16
49#define RAMP1START 32
50#define RAMP2START 48
51
52static float rotAngle = 0.;
53
54/*  Initialize antialiasing for color index mode,
55 *  including loading a green color ramp starting
56 *  at RAMP1START, and a blue color ramp starting
57 *  at RAMP2START. The ramps must be a multiple of 16.
58 */
59static void init(void)
60{
61   int i;
62
63   for (i = 0; i < RAMPSIZE; i++) {
64      GLfloat shade;
65      shade = (GLfloat) i/(GLfloat) RAMPSIZE;
66      glutSetColor(RAMP1START+(GLint)i, 0., shade, 0.);
67      glutSetColor(RAMP2START+(GLint)i, 0., 0., shade);
68   }
69
70   glEnable (GL_LINE_SMOOTH);
71   glHint (GL_LINE_SMOOTH_HINT, GL_DONT_CARE);
72   glLineWidth (1.5);
73
74   glClearIndex ((GLfloat) RAMP1START);
75}
76
77/*  Draw 2 diagonal lines to form an X
78 */
79static void display(void)
80{
81   glClear(GL_COLOR_BUFFER_BIT);
82
83   glIndexi(RAMP1START);
84   glPushMatrix();
85   glRotatef(-rotAngle, 0.0, 0.0, 0.1);
86   glBegin (GL_LINES);
87      glVertex2f (-0.5, 0.5);
88      glVertex2f (0.5, -0.5);
89   glEnd ();
90   glPopMatrix();
91
92   glIndexi(RAMP2START);
93   glPushMatrix();
94   glRotatef(rotAngle, 0.0, 0.0, 0.1);
95   glBegin (GL_LINES);
96      glVertex2f (0.5, 0.5);
97      glVertex2f (-0.5, -0.5);
98   glEnd ();
99   glPopMatrix();
100
101   glFlush();
102}
103
104static void reshape(int w, int h)
105{
106   glViewport(0, 0, (GLsizei) w, (GLsizei) h);
107   glMatrixMode(GL_PROJECTION);
108   glLoadIdentity();
109   if (w <= h)
110      gluOrtho2D (-1.0, 1.0,
111         -1.0*(GLfloat)h/(GLfloat)w, 1.0*(GLfloat)h/(GLfloat)w);
112   else
113      gluOrtho2D (-1.0*(GLfloat)w/(GLfloat)h,
114         1.0*(GLfloat)w/(GLfloat)h, -1.0, 1.0);
115   glMatrixMode(GL_MODELVIEW);
116   glLoadIdentity();
117}
118
119/* ARGSUSED1 */
120static void keyboard(unsigned char key, int x, int y)
121{
122   switch (key) {
123      case 'r':
124      case 'R':
125         rotAngle += 20.;
126         if (rotAngle >= 360.) rotAngle = 0.;
127         glutPostRedisplay();
128         break;
129      case 27:  /*  Escape Key */
130         exit(0);
131         break;
132      default:
133         break;
134    }
135}
136
137/*  Main Loop
138 *  Open window with initial window size, title bar,
139 *  color index display mode, and handle input events.
140 */
141int main(int argc, char** argv)
142{
143   glutInit(&argc, argv);
144   glutInitDisplayMode (GLUT_SINGLE | GLUT_INDEX);
145   glutInitWindowSize (200, 200);
146   glutCreateWindow (argv[0]);
147   init();
148   glutReshapeFunc (reshape);
149   glutKeyboardFunc (keyboard);
150   glutDisplayFunc (display);
151   glutMainLoop();
152   return 0;
153}
154