1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/image.c	Mon Oct 28 16:07:25 2019 +0200
     1.3 @@ -0,0 +1,485 @@
     1.4 +/*
     1.5 +colcycle - color cycling image viewer
     1.6 +Copyright (C) 2016-2017  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 <ctype.h>
    1.26 +#include <math.h>
    1.27 +#if defined(__WATCOMC__) || defined(_MSC_VER) || defined(WIN32)
    1.28 +#include <malloc.h>
    1.29 +#else
    1.30 +#include <alloca.h>
    1.31 +#endif
    1.32 +#include "image.h"
    1.33 +#include "imagelbm.h"
    1.34 +
    1.35 +#ifndef M_PI
    1.36 +#define M_PI 3.141593
    1.37 +#endif
    1.38 +
    1.39 +static int flatten_crange_list(struct image *img);
    1.40 +
    1.41 +int colc_gen_test_image(struct image *img)
    1.42 +{
    1.43 +	int i, j;
    1.44 +	unsigned char *pptr;
    1.45 +
    1.46 +	img->width = 640;
    1.47 +	img->height = 480;
    1.48 +	img->bpp = 8;
    1.49 +
    1.50 +	if(!(img->range = malloc(sizeof *img->range))) {
    1.51 +		return -1;
    1.52 +	}
    1.53 +	img->num_ranges = 1;
    1.54 +	img->range[0].low = 0;
    1.55 +	img->range[0].high = 255;
    1.56 +	img->range[0].cmode = CYCLE_NORMAL;
    1.57 +	img->range[0].rate = 5000;
    1.58 +
    1.59 +	if(!(img->pixels = malloc(img->width * img->height))) {
    1.60 +		free(img->range);
    1.61 +		return -1;
    1.62 +	}
    1.63 +
    1.64 +	for(i=0; i<256; i++) {
    1.65 +		float theta = M_PI * 2.0 * (float)i / 256.0;
    1.66 +		float r = cos(theta) * 0.5 + 0.5;
    1.67 +		float g = sin(theta) * 0.5 + 0.5;
    1.68 +		float b = -cos(theta) * 0.5 + 0.5;
    1.69 +		img->palette[i].r = (int)(r * 255.0);
    1.70 +		img->palette[i].g = (int)(g * 255.0);
    1.71 +		img->palette[i].b = (int)(b * 255.0);
    1.72 +	}
    1.73 +
    1.74 +	pptr = img->pixels;
    1.75 +	for(i=0; i<img->height; i++) {
    1.76 +		int c = (i << 8) / img->height;
    1.77 +		for(j=0; j<img->width; j++) {
    1.78 +			int chess = ((i >> 6) & 1) == ((j >> 6) & 1);
    1.79 +			*pptr++ = (chess ? c : c + 128) & 0xff;
    1.80 +		}
    1.81 +	}
    1.82 +	return 0;
    1.83 +}
    1.84 +
    1.85 +#define MAX_TOKEN_SIZE	256
    1.86 +static int image_block(FILE *fp, struct image *img);
    1.87 +static int nextc = -1;
    1.88 +static char token[MAX_TOKEN_SIZE];
    1.89 +
    1.90 +int colc_load_image(struct image *img, const char *fname)
    1.91 +{
    1.92 +	FILE *fp;
    1.93 +	int c;
    1.94 +
    1.95 +	if(!(fp = fopen(fname, "rb"))) {
    1.96 +		fprintf(stderr, "failed to open file: %s: %s\n", fname, strerror(errno));
    1.97 +		return -1;
    1.98 +	}
    1.99 +
   1.100 +	if(file_is_lbm(fp)) {
   1.101 +		if(load_image_lbm(img, fp) == -1) {
   1.102 +			fclose(fp);
   1.103 +			return -1;
   1.104 +		}
   1.105 +		fclose(fp);
   1.106 +		flatten_crange_list(img);
   1.107 +		return 0;
   1.108 +	}
   1.109 +
   1.110 +	/* find the start of the root block */
   1.111 +	while((c = fgetc(fp)) != -1 && c != '{');
   1.112 +	if(feof(fp)) {
   1.113 +		fprintf(stderr, "invalid image format, no image block found: %s\n", fname);
   1.114 +		return -1;
   1.115 +	}
   1.116 +
   1.117 +	nextc = c;	/* prime the pump with the extra char we read above */
   1.118 +	if(image_block(fp, img) == -1) {
   1.119 +		fprintf(stderr, "failed to read image block from: %s\n", fname);
   1.120 +		fclose(fp);
   1.121 +		return -1;
   1.122 +	}
   1.123 +	fclose(fp);
   1.124 +
   1.125 +	flatten_crange_list(img);
   1.126 +	return 0;
   1.127 +}
   1.128 +
   1.129 +void colc_destroy_image(struct image *img)
   1.130 +{
   1.131 +	if(img) {
   1.132 +		free(img->pixels);
   1.133 +		free(img->range);
   1.134 +		memset(img, 0, sizeof *img);
   1.135 +	}
   1.136 +}
   1.137 +
   1.138 +static int flatten_crange_list(struct image *img)
   1.139 +{
   1.140 +	struct colrange *list = img->range;
   1.141 +	struct colrange *rptr;
   1.142 +
   1.143 +	if(img->num_ranges <= 0) {
   1.144 +		return 0;
   1.145 +	}
   1.146 +
   1.147 +	if(!(img->range = malloc(img->num_ranges * sizeof *img->range))) {
   1.148 +		perror("flatten_crange_list: failed to allocate range array\n");
   1.149 +		return -1;
   1.150 +	}
   1.151 +
   1.152 +	rptr = img->range;
   1.153 +	while(list) {
   1.154 +		struct colrange *rng = list;
   1.155 +		list = list->next;
   1.156 +		*rptr++ = *rng;
   1.157 +		free(rng);
   1.158 +	}
   1.159 +	return 0;
   1.160 +}
   1.161 +
   1.162 +/* ---- parser ---- */
   1.163 +
   1.164 +enum {
   1.165 +	TOKEN_NUM,
   1.166 +	TOKEN_NAME,
   1.167 +	TOKEN_STR
   1.168 +};
   1.169 +
   1.170 +static int next_char(FILE *fp)
   1.171 +{
   1.172 +	while((nextc = fgetc(fp)) != -1 && isspace(nextc));
   1.173 +	return nextc;
   1.174 +}
   1.175 +
   1.176 +static int next_token(FILE *fp)
   1.177 +{
   1.178 +	char *ptr;
   1.179 +
   1.180 +	if(nextc == -1) {
   1.181 +		return -1;
   1.182 +	}
   1.183 +
   1.184 +	switch(nextc) {
   1.185 +	case '{':
   1.186 +	case '}':
   1.187 +	case ',':
   1.188 +	case '[':
   1.189 +	case ']':
   1.190 +	case ':':
   1.191 +		token[0] = nextc;
   1.192 +		token[1] = 0;
   1.193 +		nextc = next_char(fp);
   1.194 +		return token[0];
   1.195 +
   1.196 +	case '\'':
   1.197 +		ptr = token;
   1.198 +		nextc = next_char(fp);
   1.199 +		while(nextc != -1 && nextc != '\'') {
   1.200 +			*ptr++ = nextc;
   1.201 +			nextc = fgetc(fp);
   1.202 +		}
   1.203 +		nextc = next_char(fp);
   1.204 +		return TOKEN_STR;
   1.205 +
   1.206 +	default:
   1.207 +		break;
   1.208 +	}
   1.209 +
   1.210 +	if(isalpha(nextc)) {
   1.211 +		ptr = token;
   1.212 +		while(nextc != -1 && isalpha(nextc)) {
   1.213 +			*ptr++ = nextc;
   1.214 +			nextc = next_char(fp);
   1.215 +		}
   1.216 +		*ptr = 0;
   1.217 +		return TOKEN_NAME;
   1.218 +	}
   1.219 +	if(isdigit(nextc)) {
   1.220 +		ptr = token;
   1.221 +		while(nextc != -1 && isdigit(nextc)) {
   1.222 +			*ptr++ = nextc;
   1.223 +			nextc = next_char(fp);
   1.224 +		}
   1.225 +		*ptr = 0;
   1.226 +		return TOKEN_NUM;
   1.227 +	}
   1.228 +
   1.229 +	token[0] = nextc;
   1.230 +	token[1] = 0;
   1.231 +	fprintf(stderr, "next_token: unexpected character: %c\n", nextc);
   1.232 +	return -1;
   1.233 +}
   1.234 +
   1.235 +static int expect(FILE *fp, int tok)
   1.236 +{
   1.237 +	if(next_token(fp) != tok) {
   1.238 +		return 0;
   1.239 +	}
   1.240 +	return 1;
   1.241 +}
   1.242 +
   1.243 +static const char *toktypestr(int tok)
   1.244 +{
   1.245 +	static char buf[] = "' '";
   1.246 +	switch(tok) {
   1.247 +	case TOKEN_NUM:
   1.248 +		return "number";
   1.249 +	case TOKEN_NAME:
   1.250 +		return "name";
   1.251 +	case TOKEN_STR:
   1.252 +		return "string";
   1.253 +	default:
   1.254 +		break;
   1.255 +	}
   1.256 +	buf[1] = tok;
   1.257 +	return buf;
   1.258 +}
   1.259 +
   1.260 +#define EXPECT(fp, x) \
   1.261 +	do { \
   1.262 +		if(!expect(fp, x)) { \
   1.263 +			fprintf(stderr, "%s: expected: %s, found: %s\n", __func__, toktypestr(x), token); \
   1.264 +			return -1; \
   1.265 +		} \
   1.266 +	} while(0)
   1.267 +
   1.268 +static int palette(FILE *fp, struct image *img)
   1.269 +{
   1.270 +	int tok, cidx = 0;
   1.271 +	struct color col, *cptr;
   1.272 +
   1.273 +	EXPECT(fp, '[');
   1.274 +
   1.275 +	while((tok = next_token(fp)) == '[') {
   1.276 +		cptr = cidx < 256 ? &img->palette[cidx] : &col;
   1.277 +		++cidx;
   1.278 +
   1.279 +		EXPECT(fp, TOKEN_NUM);
   1.280 +		cptr->r = atoi(token);
   1.281 +		EXPECT(fp, ',');
   1.282 +		EXPECT(fp, TOKEN_NUM);
   1.283 +		cptr->g = atoi(token);
   1.284 +		EXPECT(fp, ',');
   1.285 +		EXPECT(fp, TOKEN_NUM);
   1.286 +		cptr->b = atoi(token);
   1.287 +		EXPECT(fp, ']');
   1.288 +
   1.289 +		if(nextc == ',') {
   1.290 +			next_token(fp);	/* skip comma */
   1.291 +		}
   1.292 +	}
   1.293 +
   1.294 +	if(tok != ']') {
   1.295 +		fprintf(stderr, "palette must be closed by a ']' token\n");
   1.296 +		return -1;
   1.297 +	}
   1.298 +	return 0;
   1.299 +}
   1.300 +
   1.301 +static int crange(FILE *fp, struct colrange *rng)
   1.302 +{
   1.303 +	int val;
   1.304 +	char name[MAX_TOKEN_SIZE];
   1.305 +
   1.306 +	EXPECT(fp, '{');
   1.307 +
   1.308 +	while(nextc != -1 && nextc != '}') {
   1.309 +		EXPECT(fp, TOKEN_NAME);
   1.310 +		strcpy(name, token);
   1.311 +		EXPECT(fp, ':');
   1.312 +		EXPECT(fp, TOKEN_NUM);
   1.313 +		val = atoi(token);
   1.314 +
   1.315 +		if(strcmp(name, "reverse") == 0) {
   1.316 +			rng->cmode = val;
   1.317 +		} else if(strcmp(name, "rate") == 0) {
   1.318 +			rng->rate = val;
   1.319 +		} else if(strcmp(name, "low") == 0) {
   1.320 +			rng->low = val;
   1.321 +		} else if(strcmp(name, "high") == 0) {
   1.322 +			rng->high = val;
   1.323 +		} else {
   1.324 +			fprintf(stderr, "invalid attribute %s in cycles range\n", name);
   1.325 +			return -1;
   1.326 +		}
   1.327 +
   1.328 +		if(nextc == ',') {
   1.329 +			next_token(fp);
   1.330 +		}
   1.331 +	}
   1.332 +
   1.333 +	EXPECT(fp, '}');
   1.334 +	return 0;
   1.335 +}
   1.336 +
   1.337 +static int cycles(FILE *fp, struct image *img)
   1.338 +{
   1.339 +	struct colrange *list = 0, *rng;
   1.340 +
   1.341 +	EXPECT(fp, '[');
   1.342 +
   1.343 +	img->num_ranges = 0;
   1.344 +	while(nextc == '{') {
   1.345 +		if(!(rng = malloc(sizeof *rng))) {
   1.346 +			perror("failed to allocate color range");
   1.347 +			goto err;
   1.348 +		}
   1.349 +		if(crange(fp, rng) == -1) {
   1.350 +			free(rng);
   1.351 +			goto err;
   1.352 +		}
   1.353 +		if(rng->low != rng->high && rng->rate > 0) {
   1.354 +			rng->next = list;
   1.355 +			list = rng;
   1.356 +			++img->num_ranges;
   1.357 +		} else {
   1.358 +			free(rng);
   1.359 +		}
   1.360 +
   1.361 +		if(nextc == ',') {
   1.362 +			next_token(fp);	/* eat the comma */
   1.363 +		}
   1.364 +	}
   1.365 +
   1.366 +	img->range = list;
   1.367 +
   1.368 +	if(!expect(fp, ']')) {
   1.369 +		fprintf(stderr, "cycles: missing closing bracket\n");
   1.370 +		goto err;
   1.371 +	}
   1.372 +	return 0;
   1.373 +
   1.374 +err:
   1.375 +	while(list) {
   1.376 +		rng = list;
   1.377 +		list = list->next;
   1.378 +		free(rng);
   1.379 +	}
   1.380 +	img->num_ranges = 0;
   1.381 +	return -1;
   1.382 +}
   1.383 +
   1.384 +static int pixels(FILE *fp, struct image *img)
   1.385 +{
   1.386 +	int tok, num_pixels;
   1.387 +	unsigned char *pptr;
   1.388 +
   1.389 +	if(img->width <= 0 || img->height <= 0) {
   1.390 +		fprintf(stderr, "pixel block found before defining the image dimensions!\n");
   1.391 +		return -1;
   1.392 +	}
   1.393 +	num_pixels = img->width * img->height;
   1.394 +	if(!(img->pixels = malloc(num_pixels))) {
   1.395 +		perror("failed to allocate pixels");
   1.396 +		return -1;
   1.397 +	}
   1.398 +	pptr = img->pixels;
   1.399 +
   1.400 +	EXPECT(fp, '[');
   1.401 +
   1.402 +	while((tok = next_token(fp)) == TOKEN_NUM) {
   1.403 +		if(pptr - img->pixels >= num_pixels) {
   1.404 +			pptr = 0;
   1.405 +			fprintf(stderr, "more pixel data provided than the specified image dimensions\n");
   1.406 +		}
   1.407 +		if(!pptr) continue;
   1.408 +		*pptr++ = atoi(token);
   1.409 +
   1.410 +		if(nextc == ',') {
   1.411 +			next_token(fp);	/* eat comma */
   1.412 +		}
   1.413 +	}
   1.414 +
   1.415 +	if(tok != ']') {
   1.416 +		printf("pixels: missing closing bracket\n");
   1.417 +		return -1;
   1.418 +	}
   1.419 +	return 0;
   1.420 +}
   1.421 +
   1.422 +static int attribute(FILE *fp, struct image *img)
   1.423 +{
   1.424 +	char *attr_name;
   1.425 +
   1.426 +	if(!expect(fp, TOKEN_NAME)) {
   1.427 +		return -1;
   1.428 +	}
   1.429 +	attr_name = alloca(strlen(token) + 1);
   1.430 +	strcpy(attr_name, token);
   1.431 +
   1.432 +	if(!expect(fp, ':')) {
   1.433 +		return -1;
   1.434 +	}
   1.435 +
   1.436 +	if(strcmp(attr_name, "filename") == 0) {
   1.437 +		if(!expect(fp, TOKEN_STR)) {
   1.438 +			fprintf(stderr, "attribute: filename should be a string\n");
   1.439 +			return -1;
   1.440 +		}
   1.441 +
   1.442 +	} else if(strcmp(attr_name, "width") == 0 || strcmp(attr_name, "height") == 0) {
   1.443 +		int *dst = attr_name[0] == 'w' ? &img->width : &img->height;
   1.444 +		if(!expect(fp, TOKEN_NUM)) {
   1.445 +			fprintf(stderr, "attribute: %s should be a number\n", attr_name);
   1.446 +			return -1;
   1.447 +		}
   1.448 +		*dst = atoi(token);
   1.449 +
   1.450 +	} else if(strcmp(attr_name, "colors") == 0) {
   1.451 +		if(palette(fp, img) == -1) {
   1.452 +			fprintf(stderr, "attribute: colors should be a palette\n");
   1.453 +			return -1;
   1.454 +		}
   1.455 +
   1.456 +	} else if(strcmp(attr_name, "cycles") == 0) {
   1.457 +		if(cycles(fp, img) == -1) {
   1.458 +			fprintf(stderr, "attribute: cycles should be a list of palranges\n");
   1.459 +			return -1;
   1.460 +		}
   1.461 +
   1.462 +	} else if(strcmp(attr_name, "pixels") == 0) {
   1.463 +		if(pixels(fp, img) == -1) {
   1.464 +			fprintf(stderr, "attribute: pixels should be a list of indices\n");
   1.465 +			return -1;
   1.466 +		}
   1.467 +
   1.468 +	} else {
   1.469 +		fprintf(stderr, "unknown attribute: %s\n", attr_name);
   1.470 +		return -1;
   1.471 +	}
   1.472 +	return 0;
   1.473 +}
   1.474 +
   1.475 +static int image_block(FILE *fp, struct image *img)
   1.476 +{
   1.477 +	EXPECT(fp, '{');
   1.478 +
   1.479 +	img->width = img->height = -1;
   1.480 +	img->bpp = 8;
   1.481 +
   1.482 +	while(attribute(fp, img) != -1) {
   1.483 +		if(nextc == ',') {
   1.484 +			next_token(fp);	/* eat comma */
   1.485 +		}
   1.486 +	}
   1.487 +	return 0;
   1.488 +}