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
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
|
/*
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.
*/
#if !EMSCRIPTEN
#define USE_GLEW 1
#endif
#if USE_GLEW
#include "GL/glew.h"
#endif
#include "SDL/SDL.h"
#if !USE_GLEW
#include "SDL/SDL_opengl.h"
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
int main(int argc, char *argv[])
{
SDL_Surface *screen;
if ( SDL_Init(SDL_INIT_VIDEO) != 0 ) {
printf("Unable to initialize SDL: %s\n", SDL_GetError());
return 1;
}
SDL_GL_SetAttribute( SDL_GL_DOUBLEBUFFER, 1 );
screen = SDL_SetVideoMode( 640, 480, 24, SDL_OPENGL );
if ( !screen ) {
printf("Unable to set video mode: %s\n", SDL_GetError());
return 1;
}
glClearColor( 0, 0, 0, 0 );
glClear( GL_COLOR_BUFFER_BIT );
// Create a texture
GLuint texture;
glGenTextures( 1, &texture );
glBindTexture( GL_TEXTURE_2D, texture );
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
GLubyte textureData[16*16*4];
for (int x = 0; x < 16; x++) {
for (int y = 0; y < 16; y++) {
*((int*)&textureData[(x*16 + y) * 4]) = x*16 + ((y*16) << 8);
}
}
glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, 16, 16, 0,
GL_RGBA, GL_UNSIGNED_BYTE, textureData );
// Create a second texture
GLuint texture2;
glGenTextures( 1, &texture2 );
glBindTexture( GL_TEXTURE_2D, texture2 );
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
GLubyte texture2Data[] = { 0xff, 0, 0, 0xff,
0, 0xff, 0, 0xaa,
0, 0, 0xff, 0x55,
0x80, 0x90, 0x70, 0 };
glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, 2, 2, 0,
GL_RGBA, GL_UNSIGNED_BYTE, texture2Data );
// BEGIN
#if USE_GLEW
glewInit();
#endif
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
// original: glFrustum(-0.6435469817188064, 0.6435469817188064 ,-0.48266022190470925, 0.48266022190470925 ,0.5400000214576721, 2048);
//glFrustum(-0.6435469817188064, 0.1435469817188064 ,-0.48266022190470925, 0.88266022190470925 ,0.5400000214576721, 2048);
GLfloat pm[] = { 1.372136116027832, 0, 0, 0, 0, 0.7910231351852417, 0, 0, -0.6352481842041016, 0.29297152161598206, -1.0005275011062622, -1, 0, 0, -1.080284833908081, 0 };
glLoadMatrixf(pm);
glMatrixMode(GL_MODELVIEW);
GLfloat matrixData[] = { -1, 0, 0, 0,
0, 0,-1, 0,
0, 1, 0, 0,
0, 0, 0, 1 };
glLoadMatrixf(matrixData);
glActiveTexture(GL_TEXTURE0);
GLuint arrayBuffer, elementBuffer;
glGenBuffers(1, &arrayBuffer);
glGenBuffers(1, &elementBuffer);
GLubyte arrayData[] = {
/*
[0, 0, 0, 67] ==> 128 float
[0, 0, 128, 67] ==> 256 float
[0, 0, 0, 68] ==> 512 float
[0, 0, 128, 68] ==> 1024 float
[vertex x ] [vertex y ] [vertex z ] [nr] [texture u ] [texture v ] [lm u ] [lm v ] [color r,g,b,a ] */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128, // 0
0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 67, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128, // 1
0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 67, 0, 0, 0, 67, 0, 0, 0, 0, 128, 128, 128, 128, // 2
0, 0, 0, 0, 0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 67, 0, 0, 0, 0, 128, 128, 128, 128, // 3
0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 67, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128, // 4
0, 0, 128, 68, 0, 0, 0, 0, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 128, 67, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128, // 5
0, 0, 128, 68, 0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 128, 67, 0, 0, 0, 67, 0, 0, 0, 0, 128, 128, 128, 128, // 6
0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 67, 0, 0, 0, 67, 0, 0, 0, 0, 128, 128, 128, 128, // 7
0, 0, 0, 0, 0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 67, 0, 0, 0, 0, 128, 128, 128, 128, // 8
0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 67, 0, 0, 0, 67, 0, 0, 0, 0, 128, 128, 128, 128, // 9
0, 0, 0, 68, 0, 0, 128, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 67, 0, 0, 128, 67, 0, 0, 0, 0, 128, 128, 128, 128, // 10
0, 0, 0, 0, 0, 0, 128, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 67, 0, 0, 0, 0, 128, 128, 128, 128, // 11
0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 67, 0, 0, 0, 67, 0, 0, 0, 0, 128, 128, 128, 128, // 12
0, 0, 128, 68, 0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 128, 67, 0, 0, 0, 67, 0, 0, 0, 0, 128, 128, 128, 128, // 13
0, 0, 128, 68, 0, 0, 128, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 128, 67, 0, 0, 128, 67, 0, 0, 0, 0, 128, 128, 128, 128, // 14
0, 0, 0, 68, 0, 0, 128, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 67, 0, 0, 128, 67, 0, 0, 0, 0, 128, 128, 128, 128, // 15
0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 128, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 128, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 0, 0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 0, 0, 0, 0, 68, 0, 0, 128, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 128, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 128, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 128, 68, 0, 0, 0, 68, 0, 0, 128, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 128, 68, 0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 128, 68, 0, 0, 0, 0, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 68, 0, 0, 128, 68, 0, 0, 128, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 128, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 68, 0, 0, 128, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 0, 0, 0, 0, 68, 0, 0, 128, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 0, 0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 0, 0, 0, 128, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 68, 0, 0, 128, 68, 0, 0, 128, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 68, 0, 0, 128, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 128, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 128, 68, 0, 0, 0, 68, 0, 0, 128, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 128, 68, 0, 0, 0, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128,
0, 0, 128, 68, 0, 0, 128, 68, 0, 0, 0, 68, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 128, 128, 128
};
assert(sizeof(arrayData) == 1408);
glBindBuffer(GL_ARRAY_BUFFER, arrayBuffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(arrayData), arrayData, GL_STATIC_DRAW);
glBindBuffer(GL_ARRAY_BUFFER, 0);
GLushort elementData[] = { 1, 2, 0, 2, 3, 0, 5, 6, 4, 6, 7, 4, 9, 10, 8, 10, 11, 8, 13, 14, 12, 14, 15, 12 };
assert(sizeof(elementData) == 48);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, elementBuffer);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(elementData), elementData, GL_STATIC_DRAW);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
glBindBuffer(GL_ARRAY_BUFFER, arrayBuffer);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, elementBuffer);
glBindTexture(GL_TEXTURE_2D, texture); // diffuse?
glActiveTexture(GL_TEXTURE0);
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_2D, texture2); // lightmap?
glActiveTexture(GL_TEXTURE0);
GLint ok;
const char *vertexShader = "attribute vec4 a_position;\n"
"attribute vec4 a_texCoord0;\n"
"uniform mat4 u_modelView;\n"
"uniform mat4 u_projection;\n"
"varying vec4 v_texCoord0;\n"
"void main(void)\n"
"{\n"
" gl_Position = (u_projection * u_modelView * a_position) + vec4(200, 0, 0, 0);\n"
" v_texCoord0.xy = a_texCoord0.xy/20.0;\n" // added /20 here
"}\n";
const char *fragmentShader = "uniform sampler2D diffusemap;\n"
"varying vec4 v_texCoord0;\n"
"void main(void)\n"
"{\n"
" vec4 diffuse = texture2D(diffusemap, v_texCoord0.xy);\n"
" gl_FragColor = diffuse;\n"
"}\n";
GLuint vs = glCreateShader(GL_VERTEX_SHADER);
glShaderSource(vs, 1, &vertexShader, NULL);
glCompileShader(vs);
glGetShaderiv(vs, GL_COMPILE_STATUS, &ok);
if (!ok) {
printf("Shader compilation error with vertex\n");
GLint infoLen = 0;
glGetShaderiv (vs, GL_INFO_LOG_LENGTH, &infoLen);
if (infoLen > 1)
{
char* infoLog = (char *)malloc(sizeof(char) * infoLen+1);
glGetShaderInfoLog(vs, infoLen, NULL, infoLog);
printf("Error compiling shader:\n%s\n", infoLog);
}
}
GLuint fs = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(fs, 1, &fragmentShader, NULL);
glCompileShader(fs);
glGetShaderiv(fs, GL_COMPILE_STATUS, &ok);
if (!ok) {
printf("Shader compilation error with fragment\n");
GLint infoLen = 0;
glGetShaderiv (vs, GL_INFO_LOG_LENGTH, &infoLen);
if (infoLen > 1)
{
char* infoLog = (char *)malloc(sizeof(char) * infoLen+1);
glGetShaderInfoLog(vs, infoLen, NULL, infoLog);
printf("Error compiling shader:\n%s\n", infoLog);
}
}
GLuint program = glCreateProgram();
glAttachShader(program, vs);
glAttachShader(program, fs);
glLinkProgram(program);
glGetProgramiv(program, GL_LINK_STATUS, &ok);
assert(ok);
glUseProgram(program);
GLint diffusemapLocation = glGetUniformLocation(program, "diffusemap");
assert(diffusemapLocation >= 0);
glUniform1i(diffusemapLocation, 0);
{
GLfloat data[16];
glGetFloatv(GL_MODELVIEW_MATRIX, data);
printf("Modelview: ");
for (int i = 0; i < 16; i++) printf("%.3f, ", data[i]);
printf("\n");
GLint modelViewLocation = glGetUniformLocation(program, "u_modelView");
assert(modelViewLocation >= 0);
glUniformMatrix4fv(modelViewLocation, 1, GL_FALSE, data);
}
{
GLfloat data[16];
glGetFloatv(GL_PROJECTION_MATRIX, data);
printf("Projection: ");
for (int i = 0; i < 16; i++) printf("%.3f, ", data[i]);
printf("\n");
GLint projectionLocation = glGetUniformLocation(program, "u_projection");
assert(projectionLocation >= 0);
glUniformMatrix4fv(projectionLocation, 1, GL_FALSE, data);
}
glBindAttribLocation(program, 0, "a_position");
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 32, (void*)0);
glEnableVertexAttribArray(0);
glBindAttribLocation(program, 1, "a_texCoord0");
glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 32, (void*)16);
glEnableVertexAttribArray(1);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, (void*)12);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, (void*) 0);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, (void*)24);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, (void*)36);
// END
SDL_GL_SwapBuffers();
#if !EMSCRIPTEN
SDL_Delay(1500);
#endif
SDL_Quit();
return 0;
}
|
