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
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
|
/*
Simple Demo for GLSL
www.lighthouse3d.com
tweaked a bit by andy
*/
#include "GL/glew.h"
#ifdef __linux__
#include <GL/glut.h>
#endif
#ifdef __APPLE__
#include <glut.h>
#endif
#ifdef _WIN32
#include "glut.h"
#endif
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
///////////////////////////////////////////////////////////////////////
char *textFileRead(char *fn)
{
FILE *fp;
char *content = NULL;
int count=0;
if (fn != NULL) {
fp = fopen(fn,"rt");
if (fp != NULL) {
fseek(fp, 0, SEEK_END);
count = ftell(fp);
rewind(fp);
if (count > 0) {
content = (char *)malloc(sizeof(char) * (count+1));
count = fread(content,sizeof(char),count,fp);
content[count] = '\0';
}
fclose(fp);
}
}
if (content == NULL)
{
fprintf(stderr, "ERROR: could not load in file %s\n", fn);
exit(1);
}
return content;
}
///////////////////////////////////////////////////////////////////////
int textFileWrite(char *fn, char *s)
{
FILE *fp;
int status = 0;
if (fn != NULL) {
fp = fopen(fn,"w");
if (fp != NULL) {
if (fwrite(s,sizeof(char),strlen(s),fp) == strlen(s))
status = 1;
fclose(fp);
}
}
return(status);
}
///////////////////////////////////////////////////////////////////////
GLuint v,f,p;
float lpos[4] = {1.0, 0.5, 1.0, 0.0};
///////////////////////////////////////////////////////////////////////
void changeSize(int w, int h)
{
// Prevent a divide by zero, when window is too short
// (you cant make a window of zero width).
if(h == 0)
h = 1;
float ratio = 1.0* w / h;
// Reset the coordinate system before modifying
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
// Set the viewport to be the entire window
glViewport(0, 0, w, h);
// Set the correct perspective.
gluPerspective(45, ratio, 1, 1000);
glMatrixMode(GL_MODELVIEW);
}
///////////////////////////////////////////////////////////////////////
void renderScene(void)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity();
gluLookAt(0.0,0.0,5.0,
0.0,0.0,-1.0,
0.0f,1.0f,0.0f);
glLightfv(GL_LIGHT0, GL_POSITION, lpos);
glutSolidTeapot(1);
glutSwapBuffers();
}
///////////////////////////////////////////////////////////////////////
void processNormalKeys(unsigned char key, int x, int y) {
if (key == 27)
exit(0);
}
///////////////////////////////////////////////////////////////////////
void setShaders()
{
char *vs,*fs;
v = glCreateShader(GL_VERTEX_SHADER);
f = glCreateShader(GL_FRAGMENT_SHADER);
// older syntax
//v = glCreateShaderObjectARB(GL_VERTEX_SHADER_ARB);
//f = glCreateShaderObjectARB(GL_FRAGMENT_SHADER_ARB);
vs = textFileRead("./toon.vert");
fs = textFileRead("./toon.frag");
const char * ff = fs;
const char * vv = vs;
glShaderSource(v, 1, &vv,NULL);
glShaderSource(f, 1, &ff,NULL);
// older syntax
//glShaderSourceARB(v, 1, &vv,NULL);
//glShaderSourceARB(f, 1, &ff,NULL);
free(vs);free(fs);
glCompileShader(v);
glCompileShader(f);
// older syntax
//glCompileShaderARB(v);
//glCompileShaderARB(f);
p = glCreateProgram();
// older syntax
//p = glCreateProgramObjectARB();
glAttachShader(p,f);
glAttachShader(p,v);
// older syntax
//glAttachObjectARB(p,f);
//glAttachObjectARB(p,v);
glLinkProgram(p);
// comment out this line to not use the shader
glUseProgram(p);
// older syntax
//glLinkProgramARB(p);
//glUseProgramObjectARB(p);
}
///////////////////////////////////////////////////////////////////////
int main(int argc, char **argv) {
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA);
glutInitWindowPosition(100,100);
glutInitWindowSize(320,320);
glutCreateWindow("GLSL");
glutDisplayFunc(renderScene);
glutIdleFunc(renderScene);
glutReshapeFunc(changeSize);
glutKeyboardFunc(processNormalKeys);
glEnable(GL_DEPTH_TEST);
glClearColor(0.0,0.0,0.0,1.0);
glewInit();
if (GLEW_ARB_vertex_shader && GLEW_ARB_fragment_shader)
printf("Ready for GLSL\n");
else {
printf("No GLSL support\n");
exit(1);
}
setShaders();
glutMainLoop();
return 0;
}
|
