tesspot: befe01bbd27f src/sdr.c

tesspot

view src/sdr.c @ 1:befe01bbd27f

tessellated the teapot

author	John Tsiombikas <nuclear@member.fsf.org>
date	Sun, 02 Dec 2012 17:16:32 +0200
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line source

1 #include <stdio.h>

2 #include <stdlib.h>

3 #include <string.h>

4 #include <errno.h>

5 #include <stdarg.h>

6 #include <assert.h>

7 #include <GL/glew.h>

9 #if defined(unix) || defined(__unix__)

10 #include <unistd.h>

11 #include <sys/stat.h>

12 #endif /* unix */

14 #include "sdr.h"

16 static const char *sdrtypestr(unsigned int sdrtype);

18 unsigned int create_vertex_shader(const char *src)

19 {

20 return create_shader(src, GL_VERTEX_SHADER);

21 }

23 unsigned int create_pixel_shader(const char *src)

24 {

25 return create_shader(src, GL_FRAGMENT_SHADER);

26 }

28 unsigned int create_tessctl_shader(const char *src)

29 {

30 return create_shader(src, GL_TESS_CONTROL_SHADER);

31 }

33 unsigned int create_tesseval_shader(const char *src)

34 {

35 return create_shader(src, GL_TESS_EVALUATION_SHADER);

36 }

38 unsigned int create_geometry_shader(const char *src)

39 {

40 return create_shader(src, GL_GEOMETRY_SHADER);

41 }

43 unsigned int create_shader(const char *src, unsigned int sdr_type)

44 {

45 unsigned int sdr;

46 int success, info_len;

47 char *info_str = 0;

48 GLenum err;

50 sdr = glCreateShader(sdr_type);

51 assert(glGetError() == GL_NO_ERROR);

52 glShaderSource(sdr, 1, &src, 0);

53 err = glGetError();

54 assert(err == GL_NO_ERROR);

55 glCompileShader(sdr);

56 assert(glGetError() == GL_NO_ERROR);

58 glGetShaderiv(sdr, GL_COMPILE_STATUS, &success);

59 assert(glGetError() == GL_NO_ERROR);

60 glGetShaderiv(sdr, GL_INFO_LOG_LENGTH, &info_len);

61 assert(glGetError() == GL_NO_ERROR);

63 if(info_len) {

64 if((info_str = malloc(info_len + 1))) {

65 glGetShaderInfoLog(sdr, info_len, 0, info_str);

66 assert(glGetError() == GL_NO_ERROR);

67 }

68 }

70 if(success) {

71 fprintf(stderr, info_str ? "done: %s\n" : "done\n", info_str);

72 } else {

73 fprintf(stderr, info_str ? "failed: %s\n" : "failed\n", info_str);

74 glDeleteShader(sdr);

75 sdr = 0;

76 }

78 free(info_str);

79 return sdr;

80 }

82 void free_shader(unsigned int sdr)

83 {

84 glDeleteShader(sdr);

85 }

87 unsigned int load_vertex_shader(const char *fname)

88 {

89 return load_shader(fname, GL_VERTEX_SHADER);

90 }

92 unsigned int load_pixel_shader(const char *fname)

93 {

94 return load_shader(fname, GL_FRAGMENT_SHADER);

95 }

97 unsigned int load_tessctl_shader(const char *fname)

98 {

99 return load_shader(fname, GL_TESS_CONTROL_SHADER);

100 }

101

102 unsigned int load_tesseval_shader(const char *fname)

103 {

104 return load_shader(fname, GL_TESS_EVALUATION_SHADER);

105 }

106

107 unsigned int load_geometry_shader(const char *fname)

108 {

109 return load_shader(fname, GL_GEOMETRY_SHADER);

110 }

111

112 unsigned int load_shader(const char *fname, unsigned int sdr_type)

113 {

114 #if defined(unix) || defined(__unix__)

115 struct stat st;

116 #endif

117 unsigned int sdr;

118 size_t filesize;

119 FILE *fp;

120 char *src;

121

122 if(!(fp = fopen(fname, "r"))) {

123 fprintf(stderr, "failed to open shader %s: %s\n", fname, strerror(errno));

124 return 0;

125 }

126

127 #if defined(unix) || defined(__unix__)

128 fstat(fileno(fp), &st);

129 filesize = st.st_size;

130 #else

131 fseek(fp, 0, SEEK_END);

132 filesize = ftell(fp);

133 fseek(fp, 0, SEEK_SET);

134 #endif /* unix */

135

136 if(!(src = malloc(filesize + 1))) {

137 fclose(fp);

138 return 0;

139 }

140 fread(src, 1, filesize, fp);

141 src[filesize] = 0;

142 fclose(fp);

143

144 fprintf(stderr, "compiling %s shader: %s... ", sdrtypestr(sdr_type), fname);

145 sdr = create_shader(src, sdr_type);

146

147 free(src);

148 return sdr;

149 }

150

151

152 unsigned int get_vertex_shader(const char *fname)

153 {

154 return get_shader(fname, GL_VERTEX_SHADER);

155 }

156

157 unsigned int get_pixel_shader(const char *fname)

158 {

159 return get_shader(fname, GL_FRAGMENT_SHADER);

160 }

161

162 unsigned int get_tessctl_shader(const char *fname)

163 {

164 return get_shader(fname, GL_TESS_CONTROL_SHADER);

165 }

166

167 unsigned int get_tesseval_shader(const char *fname)

168 {

169 return get_shader(fname, GL_TESS_EVALUATION_SHADER);

170 }

171

172 unsigned int get_geometry_shader(const char *fname)

173 {

174 return get_shader(fname, GL_GEOMETRY_SHADER);

175 }

176

177 unsigned int get_shader(const char *fname, unsigned int sdr_type)

178 {

179 unsigned int sdr;

180 if(!(sdr = load_shader(fname, sdr_type))) {

181 return 0;

182 }

183 return sdr;

184 }

185

186

187 /* ---- gpu programs ---- */

188

189 unsigned int create_program(void)

190 {

191 unsigned int prog = glCreateProgram();

192 assert(glGetError() == GL_NO_ERROR);

193 return prog;

194 }

195

196 unsigned int create_program_link(unsigned int sdr0, ...)

197 {

198 unsigned int prog, sdr;

199 va_list ap;

200

201 if(!(prog = create_program())) {

202 return 0;

203 }

204

205 attach_shader(prog, sdr0);

206 if(glGetError()) {

207 return 0;

208 }

209

210 va_start(ap, sdr0);

211 while((sdr = va_arg(ap, unsigned int))) {

212 attach_shader(prog, sdr);

213 if(glGetError()) {

214 return 0;

215 }

216 }

217 va_end(ap);

218

219 if(link_program(prog) == -1) {

220 free_program(prog);

221 return 0;

222 }

223 return prog;

224 }

225

226 unsigned int create_program_load(const char *vfile, const char *pfile)

227 {

228 unsigned int vs = 0, ps = 0;

229

230 if(vfile && *vfile && !(vs = get_vertex_shader(vfile))) {

231 return 0;

232 }

233 if(pfile && *pfile && !(ps = get_pixel_shader(pfile))) {

234 return 0;

235 }

236 return create_program_link(vs, ps, 0);

237 }

238

239 void free_program(unsigned int sdr)

240 {

241 glDeleteProgram(sdr);

242 }

243

244 void attach_shader(unsigned int prog, unsigned int sdr)

245 {

246 glAttachShader(prog, sdr);

247 assert(glGetError() == GL_NO_ERROR);

248 }

249

250 int link_program(unsigned int prog)

251 {

252 int linked, info_len, retval = 0;

253 char *info_str = 0;

254

255 glLinkProgram(prog);

256 assert(glGetError() == GL_NO_ERROR);

257 glGetProgramiv(prog, GL_LINK_STATUS, &linked);

258 assert(glGetError() == GL_NO_ERROR);

259 glGetProgramiv(prog, GL_INFO_LOG_LENGTH, &info_len);

260 assert(glGetError() == GL_NO_ERROR);

261

262 if(info_len) {

263 if((info_str = malloc(info_len + 1))) {

264 glGetProgramInfoLog(prog, info_len, 0, info_str);

265 assert(glGetError() == GL_NO_ERROR);

266 }

267 }

268

269 if(linked) {

270 fprintf(stderr, info_str ? "linking done: %s\n" : "linking done\n", info_str);

271 } else {

272 fprintf(stderr, info_str ? "linking failed: %s\n" : "linking failed\n", info_str);

273 retval = -1;

274 }

275

276 free(info_str);

277 return retval;

278 }

279

280 int bind_program(unsigned int prog)

281 {

282 GLenum err;

283

284 glUseProgram(prog);

285 if(prog && (err = glGetError()) != GL_NO_ERROR) {

286 /* maybe the program is not linked, try linking first */

287 if(err == GL_INVALID_OPERATION) {

288 if(link_program(prog) == -1) {

289 return -1;

290 }

291 glUseProgram(prog);

292 return glGetError() == GL_NO_ERROR ? 0 : -1;

293 }

294 return -1;

295 }

296 return 0;

297 }

298

299 /* ugly but I'm not going to write the same bloody code over and over */

300 #define BEGIN_UNIFORM_CODE \

301 int loc, curr_prog; \

302 glGetIntegerv(GL_CURRENT_PROGRAM, &curr_prog); \

303 if((unsigned int)curr_prog != prog && bind_program(prog) == -1) { \

304 return -1; \

305 } \

306 if((loc = glGetUniformLocation(prog, name)) != -1)

307

308 #define END_UNIFORM_CODE \

309 if((unsigned int)curr_prog != prog) { \

310 bind_program(curr_prog); \

311 } \

312 return loc == -1 ? -1 : 0

313

314 int set_uniform_int(unsigned int prog, const char *name, int val)

315 {

316 BEGIN_UNIFORM_CODE {

317 glUniform1i(loc, val);

318 }

319 END_UNIFORM_CODE;

320 }

321

322 int set_uniform_float(unsigned int prog, const char *name, float val)

323 {

324 BEGIN_UNIFORM_CODE {

325 glUniform1f(loc, val);

326 }

327 END_UNIFORM_CODE;

328 }

329

330 int set_uniform_float2(unsigned int prog, const char *name, float x, float y)

331 {

332 BEGIN_UNIFORM_CODE {

333 glUniform2f(loc, x, y);

334 }

335 END_UNIFORM_CODE;

336 }

337

338 int set_uniform_float3(unsigned int prog, const char *name, float x, float y, float z)

339 {

340 BEGIN_UNIFORM_CODE {

341 glUniform3f(loc, x, y, z);

342 }

343 END_UNIFORM_CODE;

344 }

345

346 int set_uniform_float4(unsigned int prog, const char *name, float x, float y, float z, float w)

347 {

348 BEGIN_UNIFORM_CODE {

349 glUniform4f(loc, x, y, z, w);

350 }

351 END_UNIFORM_CODE;

352 }

353

354 int set_uniform_matrix4(unsigned int prog, const char *name, float *mat)

355 {

356 BEGIN_UNIFORM_CODE {

357 glUniformMatrix4fv(loc, 1, GL_FALSE, mat);

358 }

359 END_UNIFORM_CODE;

360 }

361

362 int set_uniform_matrix4_transposed(unsigned int prog, const char *name, float *mat)

363 {

364 BEGIN_UNIFORM_CODE {

365 glUniformMatrix4fv(loc, 1, GL_TRUE, mat);

366 }

367 END_UNIFORM_CODE;

368 }

369

370 int get_attrib_loc(unsigned int prog, const char *name)

371 {

372 int loc, curr_prog;

373

374 glGetIntegerv(GL_CURRENT_PROGRAM, &curr_prog);

375 if((unsigned int)curr_prog != prog && bind_program(prog) == -1) {

376 return -1;

377 }

378

379 loc = glGetAttribLocation(prog, (char*)name);

380

381 if((unsigned int)curr_prog != prog) {

382 bind_program(curr_prog);

383 }

384 return loc;

385 }

386

387 void set_attrib_float3(int attr_loc, float x, float y, float z)

388 {

389 glVertexAttrib3f(attr_loc, x, y, z);

390 }

391

392 static const char *sdrtypestr(unsigned int sdrtype)

393 {

394 switch(sdrtype) {

395 case GL_VERTEX_SHADER:

396 return "vertex";

397 case GL_FRAGMENT_SHADER:

398 return "pixel";

399 case GL_TESS_CONTROL_SHADER:

400 return "tessellation control";

401 case GL_TESS_EVALUATION_SHADER:

402 return "tessellation evaluation";

403 case GL_GEOMETRY_SHADER:

404 return "geometry";

405

406 default:

407 break;

408 }

409 return "<unknown>";

410 }