1/*
2 * Copyright (c) 1991, 1992, 1993 Silicon Graphics, Inc.
3 *
4 * Permission to use, copy, modify, distribute, and sell this software and
5 * its documentation for any purpose is hereby granted without fee, provided
6 * that (i) the above copyright notices and this permission notice appear in
7 * all copies of the software and related documentation, and (ii) the name of
8 * Silicon Graphics may not be used in any advertising or
9 * publicity relating to the software without the specific, prior written
10 * permission of Silicon Graphics.
11 *
12 * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF
13 * ANY KIND,
14 * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
15 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
16 *
17 * IN NO EVENT SHALL SILICON GRAPHICS BE LIABLE FOR
18 * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
19 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
20 * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
21 * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
22 * OF THIS SOFTWARE.
23 */
24
25#include <stdio.h>
26#include <string.h>
27#include <stdlib.h>
28#include <GL/glew.h>
29#include "glut_wrap.h"
30
31
32#define CI_OFFSET_1 16
33#define CI_OFFSET_2 32
34
35
36GLenum doubleBuffer;
37
38static void Init(void)
39{
40   fprintf(stderr, "GL_RENDERER   = %s\n", (char *) glGetString(GL_RENDERER));
41   fprintf(stderr, "GL_VERSION    = %s\n", (char *) glGetString(GL_VERSION));
42   fprintf(stderr, "GL_VENDOR     = %s\n", (char *) glGetString(GL_VENDOR));
43   fflush(stderr);
44
45    glClearColor(0.0, 0.0, 1.0, 0.0);
46
47#define SIZE 16
48   {
49      GLubyte tex2d[SIZE][SIZE][4];
50      GLint s, t;
51
52      for (s = 0; s < SIZE; s++) {
53	 for (t = 0; t < SIZE; t++) {
54	    tex2d[t][s][0] = (s < SIZE/2) ? 0 : 255;
55	    tex2d[t][s][1] = (t < SIZE/2) ? 0 : 255;
56	    tex2d[t][s][2] = 0;
57	    tex2d[t][s][3] = ((t^s) & 3) * 63;
58	 }
59      }
60
61      glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
62      glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_R, GL_REPEAT);
63      glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
64      glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
65
66      glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
67      glTexImage2D(GL_TEXTURE_2D, 0, 4, SIZE, SIZE, 0,
68		   GL_RGBA, GL_UNSIGNED_BYTE, tex2d);
69      glPixelStorei(GL_UNPACK_ALIGNMENT, 4);
70      glEnable(GL_TEXTURE_2D);
71   }
72}
73
74static void Reshape(int width, int height)
75{
76
77    glViewport(0, 0, (GLint)width, (GLint)height);
78
79    glMatrixMode(GL_PROJECTION);
80    glLoadIdentity();
81    glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
82    glMatrixMode(GL_MODELVIEW);
83}
84
85static void Key(unsigned char key, int x, int y)
86{
87
88    switch (key) {
89      case 27:
90	exit(1);
91      default:
92	break;
93    }
94
95    glutPostRedisplay();
96}
97
98static void Draw(void)
99{
100   glClear(GL_COLOR_BUFFER_BIT);
101
102   glDisable(GL_DEPTH_TEST);
103   glDisable(GL_STENCIL_TEST);
104   glEnable(GL_ALPHA_TEST);
105   glAlphaFunc(GL_GEQUAL, 0.5);
106
107   glBegin(GL_QUADS);
108   glTexCoord2f(1,0);
109   glVertex3f( 0.9, -0.9, -30.0);
110   glTexCoord2f(1,1);
111   glVertex3f( 0.9,  0.9, -30.0);
112   glTexCoord2f(0,1);
113   glVertex3f(-0.9,  0.9, -30.0);
114   glTexCoord2f(0,0);
115   glVertex3f(-0.9,  -0.9, -30.0);
116   glEnd();
117
118
119   glFlush();
120
121   if (doubleBuffer) {
122      glutSwapBuffers();
123   }
124}
125
126static GLenum Args(int argc, char **argv)
127{
128    GLint i;
129
130    doubleBuffer = GL_FALSE;
131
132    for (i = 1; i < argc; i++) {
133        if (strcmp(argv[i], "-sb") == 0) {
134	    doubleBuffer = GL_FALSE;
135	} else if (strcmp(argv[i], "-db") == 0) {
136	    doubleBuffer = GL_TRUE;
137	} else {
138	    fprintf(stderr, "%s (Bad option).\n", argv[i]);
139	    return GL_FALSE;
140	}
141    }
142    return GL_TRUE;
143}
144
145int main(int argc, char **argv)
146{
147    GLenum type;
148
149    glutInit(&argc, argv);
150
151    if (Args(argc, argv) == GL_FALSE) {
152	exit(1);
153    }
154
155    glutInitWindowPosition(100, 0); glutInitWindowSize( 250, 250);
156
157    type = GLUT_RGB;
158    type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
159    glutInitDisplayMode(type);
160
161    if (glutCreateWindow(*argv) == GL_FALSE) {
162	exit(1);
163    }
164
165    Init();
166
167    glutReshapeFunc(Reshape);
168    glutKeyboardFunc(Key);
169    glutDisplayFunc(Draw);
170    glutMainLoop();
171	return 0;
172}
173