1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
|
/*
* Test Z values of glBitmap.
* Brian Paul
* 19 Feb 2010
*/
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <GL/glew.h>
#include <GL/glut.h>
static GLint Win = 0;
static void
PrintString(const char *s)
{
while (*s) {
glutBitmapCharacter(GLUT_BITMAP_8_BY_13, (int) *s);
s++;
}
}
static void
Display(void)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(-3.0, 3.0, -3.0, 3.0, -2.0, 2.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glColor3f(1, 1, 1);
glRasterPos2f(-2.0, 2.6);
PrintString("Z = -1.0");
glRasterPos2f(-0.5, 2.6);
PrintString("Z = 0.0");
glRasterPos2f(1.0, 2.6);
PrintString("Z = 1.0");
glColor3f(0, 0.4, 0.6);
glBegin(GL_QUADS);
glVertex3f(-2.0, -2.5, -1);
glVertex3f(-1.0, -2.5, -1);
glVertex3f(-1.0, 2.5, -1);
glVertex3f(-2.0, 2.5, -1);
glVertex3f(-0.5, -2.5, 0);
glVertex3f(0.5, -2.5, 0);
glVertex3f(0.5, 2.5, 0);
glVertex3f(-0.5, 2.5, 0);
glVertex3f(1.0, -2.5, 1);
glVertex3f(2.0, -2.5, 1);
glVertex3f(2.0, 2.5, 1);
glVertex3f(1.0, 2.5, 1);
glEnd();
glColor3f(1, 1, 1);
glRasterPos3f(-2.0, -1, -1.0);
PrintString("This is a bitmap string drawn at z = -1.0");
glRasterPos3f(-2.0, 0, 0.0);
PrintString("This is a bitmap string drawn at z = 0.0");
glRasterPos3f(-2.0, 1, 1.0);
PrintString("This is a bitmap string drawn at z = 1.0");
glRasterPos3f(-1.5, -2.8, 0.0);
PrintString("GL_DEPTH_FUNC = GL_LEQUAL");
glutSwapBuffers();
}
static void
Reshape(int width, int height)
{
glViewport(0, 0, width, height);
}
static void
Key(unsigned char key, int x, int y)
{
if (key == 27) {
glutDestroyWindow(Win);
exit(0);
}
glutPostRedisplay();
}
static void
Init(void)
{
glClearColor(0.25, 0.25, 0.25, 0.0);
glDepthFunc(GL_LEQUAL);
glEnable(GL_DEPTH_TEST);
}
int
main(int argc, char *argv[])
{
glutInitWindowSize(400, 400);
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);
Win = glutCreateWindow(argv[0]);
glewInit();
glutReshapeFunc(Reshape);
glutKeyboardFunc(Key);
glutDisplayFunc(Display);
Init();
glutMainLoop();
return 0;
}
|