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
|
/*
* Copyright 2012 The Emscripten Authors. All rights reserved.
* Emscripten is available under two separate licenses, the MIT license and the
* University of Illinois/NCSA Open Source License. Both these licenses can be
* found in the LICENSE file.
*/
/*
THIS WORK, INCLUDING THE SOURCE CODE, DOCUMENTATION
AND RELATED MEDIA AND DATA, IS PLACED INTO THE PUBLIC DOMAIN.
THE ORIGINAL AUTHOR IS KYLE FOLEY.
THIS SOFTWARE IS PROVIDED AS-IS WITHOUT WARRANTY
OF ANY KIND, NOT EVEN THE IMPLIED WARRANTY OF
MERCHANTABILITY. THE AUTHOR OF THIS SOFTWARE,
ASSUMES _NO_ RESPONSIBILITY FOR ANY CONSEQUENCE
RESULTING FROM THE USE, MODIFICATION, OR
REDISTRIBUTION OF THIS SOFTWARE.
*/
#include "SDL/SDL.h"
#include "SDL/SDL_opengl.h"
#include <stdio.h>
#include <string.h>
#include <assert.h>
// GL_ARB_shading_language_100, GL_ARB_shader_objects, GL_ARB_fragment_shader, GL_ARB_vertex_shader
PFNGLCREATEPROGRAMOBJECTARBPROC glCreateProgramObject_ = NULL;
PFNGLDELETEOBJECTARBPROC glDeleteObject_ = NULL;
PFNGLUSEPROGRAMOBJECTARBPROC glUseProgramObject_ = NULL;
PFNGLCREATESHADEROBJECTARBPROC glCreateShaderObject_ = NULL;
PFNGLSHADERSOURCEARBPROC glShaderSource_ = NULL;
PFNGLCOMPILESHADERARBPROC glCompileShader_ = NULL;
PFNGLGETOBJECTPARAMETERIVARBPROC glGetObjectParameteriv_ = NULL;
PFNGLATTACHOBJECTARBPROC glAttachObject_ = NULL;
PFNGLGETINFOLOGARBPROC glGetInfoLog_ = NULL;
PFNGLLINKPROGRAMARBPROC glLinkProgram_ = NULL;
PFNGLGETUNIFORMLOCATIONARBPROC glGetUniformLocation_ = NULL;
PFNGLUNIFORM1FARBPROC glUniform1f_ = NULL;
PFNGLUNIFORM2FARBPROC glUniform2f_ = NULL;
PFNGLUNIFORM3FARBPROC glUniform3f_ = NULL;
PFNGLUNIFORM4FARBPROC glUniform4f_ = NULL;
PFNGLUNIFORM1FVARBPROC glUniform1fv_ = NULL;
PFNGLUNIFORM2FVARBPROC glUniform2fv_ = NULL;
PFNGLUNIFORM3FVARBPROC glUniform3fv_ = NULL;
PFNGLUNIFORM4FVARBPROC glUniform4fv_ = NULL;
PFNGLUNIFORM1IARBPROC glUniform1i_ = NULL;
PFNGLBINDATTRIBLOCATIONARBPROC glBindAttribLocation_ = NULL;
PFNGLGETACTIVEUNIFORMARBPROC glGetActiveUniform_ = NULL;
void initARB() {
glCreateProgramObject_ = (PFNGLCREATEPROGRAMOBJECTARBPROC) SDL_GL_GetProcAddress("glCreateProgramObjectARB");
glDeleteObject_ = (PFNGLDELETEOBJECTARBPROC) SDL_GL_GetProcAddress("glDeleteObjectARB");
glUseProgramObject_ = (PFNGLUSEPROGRAMOBJECTARBPROC) SDL_GL_GetProcAddress("glUseProgramObjectARB");
glCreateShaderObject_ = (PFNGLCREATESHADEROBJECTARBPROC) SDL_GL_GetProcAddress("glCreateShaderObjectARB");
glShaderSource_ = (PFNGLSHADERSOURCEARBPROC) SDL_GL_GetProcAddress("glShaderSourceARB");
glCompileShader_ = (PFNGLCOMPILESHADERARBPROC) SDL_GL_GetProcAddress("glCompileShaderARB");
glGetObjectParameteriv_ = (PFNGLGETOBJECTPARAMETERIVARBPROC) SDL_GL_GetProcAddress("glGetObjectParameterivARB");
glAttachObject_ = (PFNGLATTACHOBJECTARBPROC) SDL_GL_GetProcAddress("glAttachObjectARB");
glGetInfoLog_ = (PFNGLGETINFOLOGARBPROC) SDL_GL_GetProcAddress("glGetInfoLogARB");
glLinkProgram_ = (PFNGLLINKPROGRAMARBPROC) SDL_GL_GetProcAddress("glLinkProgramARB");
glGetUniformLocation_ = (PFNGLGETUNIFORMLOCATIONARBPROC) SDL_GL_GetProcAddress("glGetUniformLocationARB");
glUniform1f_ = (PFNGLUNIFORM1FARBPROC) SDL_GL_GetProcAddress("glUniform1fARB");
glUniform2f_ = (PFNGLUNIFORM2FARBPROC) SDL_GL_GetProcAddress("glUniform2fARB");
glUniform3f_ = (PFNGLUNIFORM3FARBPROC) SDL_GL_GetProcAddress("glUniform3fARB");
glUniform4f_ = (PFNGLUNIFORM4FARBPROC) SDL_GL_GetProcAddress("glUniform4fARB");
glUniform1fv_ = (PFNGLUNIFORM1FVARBPROC) SDL_GL_GetProcAddress("glUniform1fvARB");
glUniform2fv_ = (PFNGLUNIFORM2FVARBPROC) SDL_GL_GetProcAddress("glUniform2fvARB");
glUniform3fv_ = (PFNGLUNIFORM3FVARBPROC) SDL_GL_GetProcAddress("glUniform3fvARB");
glUniform4fv_ = (PFNGLUNIFORM4FVARBPROC) SDL_GL_GetProcAddress("glUniform4fvARB");
glUniform1i_ = (PFNGLUNIFORM1IARBPROC) SDL_GL_GetProcAddress("glUniform1iARB");
glBindAttribLocation_ = (PFNGLBINDATTRIBLOCATIONARBPROC) SDL_GL_GetProcAddress("glBindAttribLocationARB");
glGetActiveUniform_ = (PFNGLGETACTIVEUNIFORMARBPROC) SDL_GL_GetProcAddress("glGetActiveUniformARB");
}
void setShaders() {
GLuint v, f, p;
GLint ok;
const char *vv = "void main() \n"
"{ \n"
" gl_Position = ftransform() + vec4(0.1, -0.25, 0, 0); \n"
"}";
const char *ff = "void main() \n"
"{ \n"
" gl_FragColor = vec4(gl_FragCoord.y/480.0, gl_FragCoord.x/640.0, 0.66, 1.0); \n"
"}";
v = glCreateShaderObject_(GL_VERTEX_SHADER);
f = glCreateShaderObject_(GL_FRAGMENT_SHADER);
glShaderSource_(v, 1, &vv,NULL);
glShaderSource_(f, 1, &ff,NULL);
glCompileShader_(v);
glGetObjectParameteriv_(v, GL_OBJECT_COMPILE_STATUS_ARB, &ok);
if (!ok) {
char msg[512];
glGetShaderInfoLog(v, sizeof msg, NULL, msg);
printf("shader compilation issue: %s\n", msg);
}
assert(ok);
glCompileShader_(f);
glGetObjectParameteriv_(f, GL_OBJECT_COMPILE_STATUS_ARB, &ok);
assert(ok);
p = glCreateProgramObject_();
glAttachObject_(p,f);
glAttachObject_(p,v);
glLinkProgram_(p);
glGetObjectParameteriv_(p, GL_OBJECT_LINK_STATUS_ARB, &ok);
assert(ok);
glUseProgramObject_(p);
}
int main(int argc, char *argv[])
{
SDL_Surface *screen;
assert(SDL_Init(SDL_INIT_VIDEO) == 0);
SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
screen = SDL_SetVideoMode( 640, 480, 16, SDL_OPENGL );
assert(screen);
glClearColor(0, 0, 0, 0);
glViewport(0, 0, 640, 480);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0, 640, 480, 0, -1, 1);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glClear(GL_COLOR_BUFFER_BIT);
initARB();
setShaders();
glColor3f(0, 1, 1); // is overridden by the shader, useful for debugging native builds
glBegin( GL_TRIANGLES );
glTexCoord2i(0, 0); glVertex3f( 10, 10, 0);
glTexCoord2i(1, 0); glVertex3f( 300, 10, 0);
glTexCoord2i(1, 1); glVertex3f( 300, 328, 0);
glEnd();
glColor3f(1, 1, 0); // is overridden by the shader, useful for debugging native builds
glBegin( GL_TRIANGLES );
glTexCoord2f(0, 0.5); glVertex3f(410, 10, 0);
glTexCoord2f(1, 0.5); glVertex3f(600, 10, 0);
glTexCoord2f(1, 1 ); glVertex3f(630, 400, 0);
glEnd();
// Test https://github.com/emscripten-core/emscripten/issues/3693
glBegin( GL_TRIANGLES );
glEnd();
SDL_GL_SwapBuffers();
#ifndef __EMSCRIPTEN__
SDL_Delay(3000);
#endif
SDL_Quit();
return 0;
}
|
