1 /*
2 * Test Z values of glBitmap.
3 * Brian Paul
4 * 19 Feb 2010
5 */
6
7
8 #include <assert.h>
9 #include <stdio.h>
10 #include <stdlib.h>
11 #include <string.h>
12 #include <math.h>
13 #include <glad/glad.h>
14 #include "glut_wrap.h"
15
16
17 static GLint Win = 0;
18
19
20 static void
PrintString(const char * s)21 PrintString(const char *s)
22 {
23 while (*s) {
24 glutBitmapCharacter(GLUT_BITMAP_8_BY_13, (int) *s);
25 s++;
26 }
27 }
28
29
30 static void
Display(void)31 Display(void)
32 {
33 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
34
35 glMatrixMode(GL_PROJECTION);
36 glLoadIdentity();
37 glOrtho(-3.0, 3.0, -3.0, 3.0, -2.0, 2.0);
38
39 glMatrixMode(GL_MODELVIEW);
40 glLoadIdentity();
41
42 glColor3f(1, 1, 1);
43 glRasterPos2f(-2.0, 2.6);
44 PrintString("Z = -1.0");
45 glRasterPos2f(-0.5, 2.6);
46 PrintString("Z = 0.0");
47 glRasterPos2f(1.0, 2.6);
48 PrintString("Z = 1.0");
49
50 glColor3f(0, 0.4, 0.6);
51 glBegin(GL_QUADS);
52 glVertex3f(-2.0, -2.5, -1);
53 glVertex3f(-1.0, -2.5, -1);
54 glVertex3f(-1.0, 2.5, -1);
55 glVertex3f(-2.0, 2.5, -1);
56
57 glVertex3f(-0.5, -2.5, 0);
58 glVertex3f(0.5, -2.5, 0);
59 glVertex3f(0.5, 2.5, 0);
60 glVertex3f(-0.5, 2.5, 0);
61
62 glVertex3f(1.0, -2.5, 1);
63 glVertex3f(2.0, -2.5, 1);
64 glVertex3f(2.0, 2.5, 1);
65 glVertex3f(1.0, 2.5, 1);
66 glEnd();
67
68 glColor3f(1, 1, 1);
69
70 glRasterPos3f(-2.0, -1, -1.0);
71 PrintString("This is a bitmap string drawn at z = -1.0");
72
73 glRasterPos3f(-2.0, 0, 0.0);
74 PrintString("This is a bitmap string drawn at z = 0.0");
75
76 glRasterPos3f(-2.0, 1, 1.0);
77 PrintString("This is a bitmap string drawn at z = 1.0");
78
79 glRasterPos3f(-1.5, -2.8, 0.0);
80 PrintString("GL_DEPTH_FUNC = GL_LEQUAL");
81
82 glutSwapBuffers();
83 }
84
85
86 static void
Reshape(int width,int height)87 Reshape(int width, int height)
88 {
89 glViewport(0, 0, width, height);
90 }
91
92
93 static void
Key(unsigned char key,int x,int y)94 Key(unsigned char key, int x, int y)
95 {
96 if (key == 27) {
97 glutDestroyWindow(Win);
98 exit(0);
99 }
100 glutPostRedisplay();
101 }
102
103
104 static void
Init(void)105 Init(void)
106 {
107 glClearColor(0.25, 0.25, 0.25, 0.0);
108 glDepthFunc(GL_LEQUAL);
109 glEnable(GL_DEPTH_TEST);
110 }
111
112
113 int
main(int argc,char * argv[])114 main(int argc, char *argv[])
115 {
116 glutInitWindowSize(400, 400);
117 glutInit(&argc, argv);
118 glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);
119 Win = glutCreateWindow(argv[0]);
120 gladLoadGL();
121 glutReshapeFunc(Reshape);
122 glutKeyboardFunc(Key);
123 glutDisplayFunc(Display);
124 Init();
125 glutMainLoop();
126 return 0;
127 }
128