1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/sdr.c	Sat Sep 21 05:22:48 2013 +0300
     1.3 @@ -0,0 +1,427 @@
     1.4 +/*
     1.5 +Printblobs - halftoning display hack
     1.6 +Copyright (C) 2013  John Tsiombikas <nuclear@member.fsf.org>
     1.7 +
     1.8 +This program is free software: you can redistribute it and/or modify
     1.9 +it under the terms of the GNU General Public License as published by
    1.10 +the Free Software Foundation, either version 3 of the License, or
    1.11 +(at your option) any later version.
    1.12 +
    1.13 +This program is distributed in the hope that it will be useful,
    1.14 +but WITHOUT ANY WARRANTY; without even the implied warranty of
    1.15 +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    1.16 +GNU General Public License for more details.
    1.17 +
    1.18 +You should have received a copy of the GNU General Public License
    1.19 +along with this program.  If not, see <http://www.gnu.org/licenses/>.
    1.20 +*/
    1.21 +#include <stdio.h>
    1.22 +#include <stdlib.h>
    1.23 +#include <string.h>
    1.24 +#include <errno.h>
    1.25 +#include <stdarg.h>
    1.26 +#include <assert.h>
    1.27 +#include <GL/glew.h>
    1.28 +
    1.29 +#if defined(unix) || defined(__unix__)
    1.30 +#include <unistd.h>
    1.31 +#include <sys/stat.h>
    1.32 +#endif	/* unix */
    1.33 +
    1.34 +#include "sdr.h"
    1.35 +
    1.36 +static const char *sdrtypestr(unsigned int sdrtype);
    1.37 +
    1.38 +unsigned int create_vertex_shader(const char *src)
    1.39 +{
    1.40 +	return create_shader(src, GL_VERTEX_SHADER);
    1.41 +}
    1.42 +
    1.43 +unsigned int create_pixel_shader(const char *src)
    1.44 +{
    1.45 +	return create_shader(src, GL_FRAGMENT_SHADER);
    1.46 +}
    1.47 +
    1.48 +unsigned int create_tessctl_shader(const char *src)
    1.49 +{
    1.50 +	return create_shader(src, GL_TESS_CONTROL_SHADER);
    1.51 +}
    1.52 +
    1.53 +unsigned int create_tesseval_shader(const char *src)
    1.54 +{
    1.55 +	return create_shader(src, GL_TESS_EVALUATION_SHADER);
    1.56 +}
    1.57 +
    1.58 +unsigned int create_geometry_shader(const char *src)
    1.59 +{
    1.60 +	return create_shader(src, GL_GEOMETRY_SHADER);
    1.61 +}
    1.62 +
    1.63 +unsigned int create_shader(const char *src, unsigned int sdr_type)
    1.64 +{
    1.65 +	unsigned int sdr;
    1.66 +	int success, info_len;
    1.67 +	char *info_str = 0;
    1.68 +	GLenum err;
    1.69 +
    1.70 +	sdr = glCreateShader(sdr_type);
    1.71 +	assert(glGetError() == GL_NO_ERROR);
    1.72 +	glShaderSource(sdr, 1, &src, 0);
    1.73 +	err = glGetError();
    1.74 +	assert(err == GL_NO_ERROR);
    1.75 +	glCompileShader(sdr);
    1.76 +	assert(glGetError() == GL_NO_ERROR);
    1.77 +
    1.78 +	glGetShaderiv(sdr, GL_COMPILE_STATUS, &success);
    1.79 +	assert(glGetError() == GL_NO_ERROR);
    1.80 +	glGetShaderiv(sdr, GL_INFO_LOG_LENGTH, &info_len);
    1.81 +	assert(glGetError() == GL_NO_ERROR);
    1.82 +
    1.83 +	if(info_len) {
    1.84 +		if((info_str = malloc(info_len + 1))) {
    1.85 +			glGetShaderInfoLog(sdr, info_len, 0, info_str);
    1.86 +			assert(glGetError() == GL_NO_ERROR);
    1.87 +		}
    1.88 +	}
    1.89 +
    1.90 +	if(success) {
    1.91 +		fprintf(stderr, info_str ? "done: %s\n" : "done\n", info_str);
    1.92 +	} else {
    1.93 +		fprintf(stderr, info_str ? "failed: %s\n" : "failed\n", info_str);
    1.94 +		glDeleteShader(sdr);
    1.95 +		sdr = 0;
    1.96 +	}
    1.97 +
    1.98 +	free(info_str);
    1.99 +	return sdr;
   1.100 +}
   1.101 +
   1.102 +void free_shader(unsigned int sdr)
   1.103 +{
   1.104 +	glDeleteShader(sdr);
   1.105 +}
   1.106 +
   1.107 +unsigned int load_vertex_shader(const char *fname)
   1.108 +{
   1.109 +	return load_shader(fname, GL_VERTEX_SHADER);
   1.110 +}
   1.111 +
   1.112 +unsigned int load_pixel_shader(const char *fname)
   1.113 +{
   1.114 +	return load_shader(fname, GL_FRAGMENT_SHADER);
   1.115 +}
   1.116 +
   1.117 +unsigned int load_tessctl_shader(const char *fname)
   1.118 +{
   1.119 +	return load_shader(fname, GL_TESS_CONTROL_SHADER);
   1.120 +}
   1.121 +
   1.122 +unsigned int load_tesseval_shader(const char *fname)
   1.123 +{
   1.124 +	return load_shader(fname, GL_TESS_EVALUATION_SHADER);
   1.125 +}
   1.126 +
   1.127 +unsigned int load_geometry_shader(const char *fname)
   1.128 +{
   1.129 +	return load_shader(fname, GL_GEOMETRY_SHADER);
   1.130 +}
   1.131 +
   1.132 +unsigned int load_shader(const char *fname, unsigned int sdr_type)
   1.133 +{
   1.134 +#if defined(unix) || defined(__unix__)
   1.135 +	struct stat st;
   1.136 +#endif
   1.137 +	unsigned int sdr;
   1.138 +	size_t filesize;
   1.139 +	FILE *fp;
   1.140 +	char *src;
   1.141 +
   1.142 +	if(!(fp = fopen(fname, "r"))) {
   1.143 +		fprintf(stderr, "failed to open shader %s: %s\n", fname, strerror(errno));
   1.144 +		return 0;
   1.145 +	}
   1.146 +
   1.147 +#if defined(unix) || defined(__unix__)
   1.148 +	fstat(fileno(fp), &st);
   1.149 +	filesize = st.st_size;
   1.150 +#else
   1.151 +	fseek(fp, 0, SEEK_END);
   1.152 +	filesize = ftell(fp);
   1.153 +	fseek(fp, 0, SEEK_SET);
   1.154 +#endif	/* unix */
   1.155 +
   1.156 +	if(!(src = malloc(filesize + 1))) {
   1.157 +		fclose(fp);
   1.158 +		return 0;
   1.159 +	}
   1.160 +	fread(src, 1, filesize, fp);
   1.161 +	src[filesize] = 0;
   1.162 +	fclose(fp);
   1.163 +
   1.164 +	fprintf(stderr, "compiling %s shader: %s... ", sdrtypestr(sdr_type), fname);
   1.165 +	sdr = create_shader(src, sdr_type);
   1.166 +
   1.167 +	free(src);
   1.168 +	return sdr;
   1.169 +}
   1.170 +
   1.171 +
   1.172 +unsigned int get_vertex_shader(const char *fname)
   1.173 +{
   1.174 +	return get_shader(fname, GL_VERTEX_SHADER);
   1.175 +}
   1.176 +
   1.177 +unsigned int get_pixel_shader(const char *fname)
   1.178 +{
   1.179 +	return get_shader(fname, GL_FRAGMENT_SHADER);
   1.180 +}
   1.181 +
   1.182 +unsigned int get_tessctl_shader(const char *fname)
   1.183 +{
   1.184 +	return get_shader(fname, GL_TESS_CONTROL_SHADER);
   1.185 +}
   1.186 +
   1.187 +unsigned int get_tesseval_shader(const char *fname)
   1.188 +{
   1.189 +	return get_shader(fname, GL_TESS_EVALUATION_SHADER);
   1.190 +}
   1.191 +
   1.192 +unsigned int get_geometry_shader(const char *fname)
   1.193 +{
   1.194 +	return get_shader(fname, GL_GEOMETRY_SHADER);
   1.195 +}
   1.196 +
   1.197 +unsigned int get_shader(const char *fname, unsigned int sdr_type)
   1.198 +{
   1.199 +	unsigned int sdr;
   1.200 +	if(!(sdr = load_shader(fname, sdr_type))) {
   1.201 +		return 0;
   1.202 +	}
   1.203 +	return sdr;
   1.204 +}
   1.205 +
   1.206 +
   1.207 +/* ---- gpu programs ---- */
   1.208 +
   1.209 +unsigned int create_program(void)
   1.210 +{
   1.211 +	unsigned int prog = glCreateProgram();
   1.212 +	assert(glGetError() == GL_NO_ERROR);
   1.213 +	return prog;
   1.214 +}
   1.215 +
   1.216 +unsigned int create_program_link(unsigned int sdr0, ...)
   1.217 +{
   1.218 +	unsigned int prog, sdr;
   1.219 +	va_list ap;
   1.220 +
   1.221 +	if(!(prog = create_program())) {
   1.222 +		return 0;
   1.223 +	}
   1.224 +
   1.225 +	attach_shader(prog, sdr0);
   1.226 +	if(glGetError()) {
   1.227 +		return 0;
   1.228 +	}
   1.229 +
   1.230 +	va_start(ap, sdr0);
   1.231 +	while((sdr = va_arg(ap, unsigned int))) {
   1.232 +		attach_shader(prog, sdr);
   1.233 +		if(glGetError()) {
   1.234 +			return 0;
   1.235 +		}
   1.236 +	}
   1.237 +	va_end(ap);
   1.238 +
   1.239 +	if(link_program(prog) == -1) {
   1.240 +		free_program(prog);
   1.241 +		return 0;
   1.242 +	}
   1.243 +	return prog;
   1.244 +}
   1.245 +
   1.246 +unsigned int create_program_load(const char *vfile, const char *pfile)
   1.247 +{
   1.248 +	unsigned int vs = 0, ps = 0;
   1.249 +
   1.250 +	if(vfile && *vfile && !(vs = get_vertex_shader(vfile))) {
   1.251 +		return 0;
   1.252 +	}
   1.253 +	if(pfile && *pfile && !(ps = get_pixel_shader(pfile))) {
   1.254 +		return 0;
   1.255 +	}
   1.256 +	return create_program_link(vs, ps, 0);
   1.257 +}
   1.258 +
   1.259 +void free_program(unsigned int sdr)
   1.260 +{
   1.261 +	glDeleteProgram(sdr);
   1.262 +}
   1.263 +
   1.264 +void attach_shader(unsigned int prog, unsigned int sdr)
   1.265 +{
   1.266 +	glAttachShader(prog, sdr);
   1.267 +	assert(glGetError() == GL_NO_ERROR);
   1.268 +}
   1.269 +
   1.270 +int link_program(unsigned int prog)
   1.271 +{
   1.272 +	int linked, info_len, retval = 0;
   1.273 +	char *info_str = 0;
   1.274 +
   1.275 +	glLinkProgram(prog);
   1.276 +	assert(glGetError() == GL_NO_ERROR);
   1.277 +	glGetProgramiv(prog, GL_LINK_STATUS, &linked);
   1.278 +	assert(glGetError() == GL_NO_ERROR);
   1.279 +	glGetProgramiv(prog, GL_INFO_LOG_LENGTH, &info_len);
   1.280 +	assert(glGetError() == GL_NO_ERROR);
   1.281 +
   1.282 +	if(info_len) {
   1.283 +		if((info_str = malloc(info_len + 1))) {
   1.284 +			glGetProgramInfoLog(prog, info_len, 0, info_str);
   1.285 +			assert(glGetError() == GL_NO_ERROR);
   1.286 +		}
   1.287 +	}
   1.288 +
   1.289 +	if(linked) {
   1.290 +		fprintf(stderr, info_str ? "linking done: %s\n" : "linking done\n", info_str);
   1.291 +	} else {
   1.292 +		fprintf(stderr, info_str ? "linking failed: %s\n" : "linking failed\n", info_str);
   1.293 +		retval = -1;
   1.294 +	}
   1.295 +
   1.296 +	free(info_str);
   1.297 +	return retval;
   1.298 +}
   1.299 +
   1.300 +int bind_program(unsigned int prog)
   1.301 +{
   1.302 +	GLenum err;
   1.303 +
   1.304 +	glUseProgram(prog);
   1.305 +	if(prog && (err = glGetError()) != GL_NO_ERROR) {
   1.306 +		/* maybe the program is not linked, try linking first */
   1.307 +		if(err == GL_INVALID_OPERATION) {
   1.308 +			if(link_program(prog) == -1) {
   1.309 +				return -1;
   1.310 +			}
   1.311 +			glUseProgram(prog);
   1.312 +			return glGetError() == GL_NO_ERROR ? 0 : -1;
   1.313 +		}
   1.314 +		return -1;
   1.315 +	}
   1.316 +	return 0;
   1.317 +}
   1.318 +
   1.319 +/* ugly but I'm not going to write the same bloody code over and over */
   1.320 +#define BEGIN_UNIFORM_CODE \
   1.321 +	int loc, curr_prog; \
   1.322 +	glGetIntegerv(GL_CURRENT_PROGRAM, &curr_prog); \
   1.323 +	if((unsigned int)curr_prog != prog && bind_program(prog) == -1) { \
   1.324 +		return -1; \
   1.325 +	} \
   1.326 +	if((loc = glGetUniformLocation(prog, name)) != -1)
   1.327 +
   1.328 +#define END_UNIFORM_CODE \
   1.329 +	if((unsigned int)curr_prog != prog) { \
   1.330 +		bind_program(curr_prog); \
   1.331 +	} \
   1.332 +	return loc == -1 ? -1 : 0
   1.333 +
   1.334 +int set_uniform_int(unsigned int prog, const char *name, int val)
   1.335 +{
   1.336 +	BEGIN_UNIFORM_CODE {
   1.337 +		glUniform1i(loc, val);
   1.338 +	}
   1.339 +	END_UNIFORM_CODE;
   1.340 +}
   1.341 +
   1.342 +int set_uniform_float(unsigned int prog, const char *name, float val)
   1.343 +{
   1.344 +	BEGIN_UNIFORM_CODE {
   1.345 +		glUniform1f(loc, val);
   1.346 +	}
   1.347 +	END_UNIFORM_CODE;
   1.348 +}
   1.349 +
   1.350 +int set_uniform_float2(unsigned int prog, const char *name, float x, float y)
   1.351 +{
   1.352 +	BEGIN_UNIFORM_CODE {
   1.353 +		glUniform2f(loc, x, y);
   1.354 +	}
   1.355 +	END_UNIFORM_CODE;
   1.356 +}
   1.357 +
   1.358 +int set_uniform_float3(unsigned int prog, const char *name, float x, float y, float z)
   1.359 +{
   1.360 +	BEGIN_UNIFORM_CODE {
   1.361 +		glUniform3f(loc, x, y, z);
   1.362 +	}
   1.363 +	END_UNIFORM_CODE;
   1.364 +}
   1.365 +
   1.366 +int set_uniform_float4(unsigned int prog, const char *name, float x, float y, float z, float w)
   1.367 +{
   1.368 +	BEGIN_UNIFORM_CODE {
   1.369 +		glUniform4f(loc, x, y, z, w);
   1.370 +	}
   1.371 +	END_UNIFORM_CODE;
   1.372 +}
   1.373 +
   1.374 +int set_uniform_matrix4(unsigned int prog, const char *name, float *mat)
   1.375 +{
   1.376 +	BEGIN_UNIFORM_CODE {
   1.377 +		glUniformMatrix4fv(loc, 1, GL_FALSE, mat);
   1.378 +	}
   1.379 +	END_UNIFORM_CODE;
   1.380 +}
   1.381 +
   1.382 +int set_uniform_matrix4_transposed(unsigned int prog, const char *name, float *mat)
   1.383 +{
   1.384 +	BEGIN_UNIFORM_CODE {
   1.385 +		glUniformMatrix4fv(loc, 1, GL_TRUE, mat);
   1.386 +	}
   1.387 +	END_UNIFORM_CODE;
   1.388 +}
   1.389 +
   1.390 +int get_attrib_loc(unsigned int prog, const char *name)
   1.391 +{
   1.392 +	int loc, curr_prog;
   1.393 +
   1.394 +	glGetIntegerv(GL_CURRENT_PROGRAM, &curr_prog);
   1.395 +	if((unsigned int)curr_prog != prog && bind_program(prog) == -1) {
   1.396 +		return -1;
   1.397 +	}
   1.398 +
   1.399 +	loc = glGetAttribLocation(prog, (char*)name);
   1.400 +
   1.401 +	if((unsigned int)curr_prog != prog) {
   1.402 +		bind_program(curr_prog);
   1.403 +	}
   1.404 +	return loc;
   1.405 +}
   1.406 +
   1.407 +void set_attrib_float3(int attr_loc, float x, float y, float z)
   1.408 +{
   1.409 +	glVertexAttrib3f(attr_loc, x, y, z);
   1.410 +}
   1.411 +
   1.412 +static const char *sdrtypestr(unsigned int sdrtype)
   1.413 +{
   1.414 +	switch(sdrtype) {
   1.415 +	case GL_VERTEX_SHADER:
   1.416 +		return "vertex";
   1.417 +	case GL_FRAGMENT_SHADER:
   1.418 +		return "pixel";
   1.419 +	case GL_TESS_CONTROL_SHADER:
   1.420 +		return "tessellation control";
   1.421 +	case GL_TESS_EVALUATION_SHADER:
   1.422 +		return "tessellation evaluation";
   1.423 +	case GL_GEOMETRY_SHADER:
   1.424 +		return "geometry";
   1.425 +
   1.426 +	default:
   1.427 +		break;
   1.428 +	}
   1.429 +	return "<unknown>";
   1.430 +}