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31 * Unpublished-- rights reserved under the copyright laws of the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 * aargb.c
40 * This program draws shows how to draw anti-aliased lines. It draws
41 * two diagonal lines to form an X; when 'r' is typed in the window,
42 * the lines are rotated in opposite directions.
43 */
44 #include "glut_wrap.h"
45 #include <stdlib.h>
46 #include <stdio.h>
47
48 static float rotAngle = 0.;
49
50 /* Initialize antialiasing for RGBA mode, including alpha
51 * blending, hint, and line width. Print out implementation
52 * specific info on line width granularity and width.
53 */
init(void)54 static void init(void)
55 {
56 GLfloat values[2];
57 glGetFloatv (GL_LINE_WIDTH_GRANULARITY, values);
58 printf ("GL_LINE_WIDTH_GRANULARITY value is %3.1f\n", values[0]);
59
60 glGetFloatv (GL_LINE_WIDTH_RANGE, values);
61 printf ("GL_LINE_WIDTH_RANGE values are %3.1f %3.1f\n",
62 values[0], values[1]);
63
64 glEnable (GL_LINE_SMOOTH);
65 glEnable (GL_BLEND);
66 glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
67 glHint (GL_LINE_SMOOTH_HINT, GL_DONT_CARE);
68 glLineWidth (1.5);
69
70 glClearColor(0.0, 0.0, 0.0, 0.0);
71 }
72
73 /* Draw 2 diagonal lines to form an X
74 */
display(void)75 static void display(void)
76 {
77 glClear(GL_COLOR_BUFFER_BIT);
78
79 glColor3f (0.0, 1.0, 0.0);
80 glPushMatrix();
81 glRotatef(-rotAngle, 0.0, 0.0, 0.1);
82 glBegin (GL_LINES);
83 glVertex2f (-0.5, 0.5);
84 glVertex2f (0.5, -0.5);
85 glEnd ();
86 glPopMatrix();
87
88 glColor3f (0.0, 0.0, 1.0);
89 glPushMatrix();
90 glRotatef(rotAngle, 0.0, 0.0, 0.1);
91 glBegin (GL_LINES);
92 glVertex2f (0.5, 0.5);
93 glVertex2f (-0.5, -0.5);
94 glEnd ();
95 glPopMatrix();
96
97 glFlush();
98 }
99
reshape(int w,int h)100 static void reshape(int w, int h)
101 {
102 glViewport(0, 0, w, h);
103 glMatrixMode(GL_PROJECTION);
104 glLoadIdentity();
105 if (w <= h)
106 gluOrtho2D (-1.0, 1.0,
107 -1.0*(GLfloat)h/(GLfloat)w, 1.0*(GLfloat)h/(GLfloat)w);
108 else
109 gluOrtho2D (-1.0*(GLfloat)w/(GLfloat)h,
110 1.0*(GLfloat)w/(GLfloat)h, -1.0, 1.0);
111 glMatrixMode(GL_MODELVIEW);
112 glLoadIdentity();
113 }
114
115 /* ARGSUSED1 */
keyboard(unsigned char key,int x,int y)116 static void keyboard(unsigned char key, int x, int y)
117 {
118 switch (key) {
119 case 'r':
120 case 'R':
121 rotAngle += 20.;
122 if (rotAngle >= 360.) rotAngle = 0.;
123 glutPostRedisplay();
124 break;
125 case 27: /* Escape Key */
126 exit(0);
127 break;
128 default:
129 break;
130 }
131 }
132
133 /* Main Loop
134 * Open window with initial window size, title bar,
135 * RGBA display mode, and handle input events.
136 */
main(int argc,char ** argv)137 int main(int argc, char** argv)
138 {
139 glutInit(&argc, argv);
140 glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);
141 glutInitWindowSize (200, 200);
142 glutCreateWindow (argv[0]);
143 init();
144 glutReshapeFunc (reshape);
145 glutKeyboardFunc (keyboard);
146 glutDisplayFunc (display);
147 glutMainLoop();
148 return 0;
149 }
150