nuclear@2: /*
nuclear@2: colcycle - color cycling image viewer
nuclear@2: Copyright (C) 2016-2017  John Tsiombikas <nuclear@member.fsf.org>
nuclear@2: 
nuclear@2: This program is free software: you can redistribute it and/or modify
nuclear@2: it under the terms of the GNU General Public License as published by
nuclear@2: the Free Software Foundation, either version 3 of the License, or
nuclear@2: (at your option) any later version.
nuclear@2: 
nuclear@2: This program is distributed in the hope that it will be useful,
nuclear@2: but WITHOUT ANY WARRANTY; without even the implied warranty of
nuclear@2: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
nuclear@2: GNU General Public License for more details.
nuclear@2: 
nuclear@2: You should have received a copy of the GNU General Public License
nuclear@2: along with this program.  If not, see <http://www.gnu.org/licenses/>.
nuclear@2: */
nuclear@2: #include <stdio.h>
nuclear@2: #include <stdlib.h>
nuclear@2: #include <string.h>
nuclear@2: #include <errno.h>
nuclear@2: #include <ctype.h>
nuclear@2: #include <math.h>
nuclear@2: #if defined(__WATCOMC__) || defined(_MSC_VER) || defined(WIN32)
nuclear@2: #include <malloc.h>
nuclear@2: #else
nuclear@2: #include <alloca.h>
nuclear@2: #endif
nuclear@2: #include "image.h"
nuclear@2: #include "imagelbm.h"
nuclear@2: 
nuclear@2: #ifndef M_PI
nuclear@2: #define M_PI 3.141593
nuclear@2: #endif
nuclear@2: 
nuclear@2: static int flatten_crange_list(struct image *img);
nuclear@2: 
nuclear@2: int colc_gen_test_image(struct image *img)
nuclear@2: {
nuclear@2: 	int i, j;
nuclear@2: 	unsigned char *pptr;
nuclear@2: 
nuclear@2: 	img->width = 640;
nuclear@2: 	img->height = 480;
nuclear@2: 	img->bpp = 8;
nuclear@2: 
nuclear@2: 	if(!(img->range = malloc(sizeof *img->range))) {
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 	img->num_ranges = 1;
nuclear@2: 	img->range[0].low = 0;
nuclear@2: 	img->range[0].high = 255;
nuclear@2: 	img->range[0].cmode = CYCLE_NORMAL;
nuclear@2: 	img->range[0].rate = 5000;
nuclear@2: 
nuclear@2: 	if(!(img->pixels = malloc(img->width * img->height))) {
nuclear@2: 		free(img->range);
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	for(i=0; i<256; i++) {
nuclear@2: 		float theta = M_PI * 2.0 * (float)i / 256.0;
nuclear@2: 		float r = cos(theta) * 0.5 + 0.5;
nuclear@2: 		float g = sin(theta) * 0.5 + 0.5;
nuclear@2: 		float b = -cos(theta) * 0.5 + 0.5;
nuclear@2: 		img->palette[i].r = (int)(r * 255.0);
nuclear@2: 		img->palette[i].g = (int)(g * 255.0);
nuclear@2: 		img->palette[i].b = (int)(b * 255.0);
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	pptr = img->pixels;
nuclear@2: 	for(i=0; i<img->height; i++) {
nuclear@2: 		int c = (i << 8) / img->height;
nuclear@2: 		for(j=0; j<img->width; j++) {
nuclear@2: 			int chess = ((i >> 6) & 1) == ((j >> 6) & 1);
nuclear@2: 			*pptr++ = (chess ? c : c + 128) & 0xff;
nuclear@2: 		}
nuclear@2: 	}
nuclear@2: 	return 0;
nuclear@2: }
nuclear@2: 
nuclear@2: #define MAX_TOKEN_SIZE	256
nuclear@2: static int image_block(FILE *fp, struct image *img);
nuclear@2: static int nextc = -1;
nuclear@2: static char token[MAX_TOKEN_SIZE];
nuclear@2: 
nuclear@2: int colc_load_image(struct image *img, const char *fname)
nuclear@2: {
nuclear@2: 	FILE *fp;
nuclear@2: 	int c;
nuclear@2: 
nuclear@2: 	if(!(fp = fopen(fname, "rb"))) {
nuclear@2: 		fprintf(stderr, "failed to open file: %s: %s\n", fname, strerror(errno));
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	if(file_is_lbm(fp)) {
nuclear@2: 		if(load_image_lbm(img, fp) == -1) {
nuclear@2: 			fclose(fp);
nuclear@2: 			return -1;
nuclear@2: 		}
nuclear@2: 		fclose(fp);
nuclear@2: 		flatten_crange_list(img);
nuclear@2: 		return 0;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	/* find the start of the root block */
nuclear@2: 	while((c = fgetc(fp)) != -1 && c != '{');
nuclear@2: 	if(feof(fp)) {
nuclear@2: 		fprintf(stderr, "invalid image format, no image block found: %s\n", fname);
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	nextc = c;	/* prime the pump with the extra char we read above */
nuclear@2: 	if(image_block(fp, img) == -1) {
nuclear@2: 		fprintf(stderr, "failed to read image block from: %s\n", fname);
nuclear@2: 		fclose(fp);
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 	fclose(fp);
nuclear@2: 
nuclear@2: 	flatten_crange_list(img);
nuclear@2: 	return 0;
nuclear@2: }
nuclear@2: 
nuclear@2: void colc_destroy_image(struct image *img)
nuclear@2: {
nuclear@2: 	if(img) {
nuclear@2: 		free(img->pixels);
nuclear@2: 		free(img->range);
nuclear@2: 		memset(img, 0, sizeof *img);
nuclear@2: 	}
nuclear@2: }
nuclear@2: 
nuclear@2: static int flatten_crange_list(struct image *img)
nuclear@2: {
nuclear@2: 	struct colrange *list = img->range;
nuclear@2: 	struct colrange *rptr;
nuclear@2: 
nuclear@2: 	if(img->num_ranges <= 0) {
nuclear@2: 		return 0;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	if(!(img->range = malloc(img->num_ranges * sizeof *img->range))) {
nuclear@2: 		perror("flatten_crange_list: failed to allocate range array\n");
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	rptr = img->range;
nuclear@2: 	while(list) {
nuclear@2: 		struct colrange *rng = list;
nuclear@2: 		list = list->next;
nuclear@2: 		*rptr++ = *rng;
nuclear@2: 		free(rng);
nuclear@2: 	}
nuclear@2: 	return 0;
nuclear@2: }
nuclear@2: 
nuclear@2: /* ---- parser ---- */
nuclear@2: 
nuclear@2: enum {
nuclear@2: 	TOKEN_NUM,
nuclear@2: 	TOKEN_NAME,
nuclear@2: 	TOKEN_STR
nuclear@2: };
nuclear@2: 
nuclear@2: static int next_char(FILE *fp)
nuclear@2: {
nuclear@2: 	while((nextc = fgetc(fp)) != -1 && isspace(nextc));
nuclear@2: 	return nextc;
nuclear@2: }
nuclear@2: 
nuclear@2: static int next_token(FILE *fp)
nuclear@2: {
nuclear@2: 	char *ptr;
nuclear@2: 
nuclear@2: 	if(nextc == -1) {
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	switch(nextc) {
nuclear@2: 	case '{':
nuclear@2: 	case '}':
nuclear@2: 	case ',':
nuclear@2: 	case '[':
nuclear@2: 	case ']':
nuclear@2: 	case ':':
nuclear@2: 		token[0] = nextc;
nuclear@2: 		token[1] = 0;
nuclear@2: 		nextc = next_char(fp);
nuclear@2: 		return token[0];
nuclear@2: 
nuclear@2: 	case '\'':
nuclear@2: 		ptr = token;
nuclear@2: 		nextc = next_char(fp);
nuclear@2: 		while(nextc != -1 && nextc != '\'') {
nuclear@2: 			*ptr++ = nextc;
nuclear@2: 			nextc = fgetc(fp);
nuclear@2: 		}
nuclear@2: 		nextc = next_char(fp);
nuclear@2: 		return TOKEN_STR;
nuclear@2: 
nuclear@2: 	default:
nuclear@2: 		break;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	if(isalpha(nextc)) {
nuclear@2: 		ptr = token;
nuclear@2: 		while(nextc != -1 && isalpha(nextc)) {
nuclear@2: 			*ptr++ = nextc;
nuclear@2: 			nextc = next_char(fp);
nuclear@2: 		}
nuclear@2: 		*ptr = 0;
nuclear@2: 		return TOKEN_NAME;
nuclear@2: 	}
nuclear@2: 	if(isdigit(nextc)) {
nuclear@2: 		ptr = token;
nuclear@2: 		while(nextc != -1 && isdigit(nextc)) {
nuclear@2: 			*ptr++ = nextc;
nuclear@2: 			nextc = next_char(fp);
nuclear@2: 		}
nuclear@2: 		*ptr = 0;
nuclear@2: 		return TOKEN_NUM;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	token[0] = nextc;
nuclear@2: 	token[1] = 0;
nuclear@2: 	fprintf(stderr, "next_token: unexpected character: %c\n", nextc);
nuclear@2: 	return -1;
nuclear@2: }
nuclear@2: 
nuclear@2: static int expect(FILE *fp, int tok)
nuclear@2: {
nuclear@2: 	if(next_token(fp) != tok) {
nuclear@2: 		return 0;
nuclear@2: 	}
nuclear@2: 	return 1;
nuclear@2: }
nuclear@2: 
nuclear@2: static const char *toktypestr(int tok)
nuclear@2: {
nuclear@2: 	static char buf[] = "' '";
nuclear@2: 	switch(tok) {
nuclear@2: 	case TOKEN_NUM:
nuclear@2: 		return "number";
nuclear@2: 	case TOKEN_NAME:
nuclear@2: 		return "name";
nuclear@2: 	case TOKEN_STR:
nuclear@2: 		return "string";
nuclear@2: 	default:
nuclear@2: 		break;
nuclear@2: 	}
nuclear@2: 	buf[1] = tok;
nuclear@2: 	return buf;
nuclear@2: }
nuclear@2: 
nuclear@2: #define EXPECT(fp, x) \
nuclear@2: 	do { \
nuclear@2: 		if(!expect(fp, x)) { \
nuclear@2: 			fprintf(stderr, "%s: expected: %s, found: %s\n", __func__, toktypestr(x), token); \
nuclear@2: 			return -1; \
nuclear@2: 		} \
nuclear@2: 	} while(0)
nuclear@2: 
nuclear@2: static int palette(FILE *fp, struct image *img)
nuclear@2: {
nuclear@2: 	int tok, cidx = 0;
nuclear@2: 	struct color col, *cptr;
nuclear@2: 
nuclear@2: 	EXPECT(fp, '[');
nuclear@2: 
nuclear@2: 	while((tok = next_token(fp)) == '[') {
nuclear@2: 		cptr = cidx < 256 ? &img->palette[cidx] : &col;
nuclear@2: 		++cidx;
nuclear@2: 
nuclear@2: 		EXPECT(fp, TOKEN_NUM);
nuclear@2: 		cptr->r = atoi(token);
nuclear@2: 		EXPECT(fp, ',');
nuclear@2: 		EXPECT(fp, TOKEN_NUM);
nuclear@2: 		cptr->g = atoi(token);
nuclear@2: 		EXPECT(fp, ',');
nuclear@2: 		EXPECT(fp, TOKEN_NUM);
nuclear@2: 		cptr->b = atoi(token);
nuclear@2: 		EXPECT(fp, ']');
nuclear@2: 
nuclear@2: 		if(nextc == ',') {
nuclear@2: 			next_token(fp);	/* skip comma */
nuclear@2: 		}
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	if(tok != ']') {
nuclear@2: 		fprintf(stderr, "palette must be closed by a ']' token\n");
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 	return 0;
nuclear@2: }
nuclear@2: 
nuclear@2: static int crange(FILE *fp, struct colrange *rng)
nuclear@2: {
nuclear@2: 	int val;
nuclear@2: 	char name[MAX_TOKEN_SIZE];
nuclear@2: 
nuclear@2: 	EXPECT(fp, '{');
nuclear@2: 
nuclear@2: 	while(nextc != -1 && nextc != '}') {
nuclear@2: 		EXPECT(fp, TOKEN_NAME);
nuclear@2: 		strcpy(name, token);
nuclear@2: 		EXPECT(fp, ':');
nuclear@2: 		EXPECT(fp, TOKEN_NUM);
nuclear@2: 		val = atoi(token);
nuclear@2: 
nuclear@2: 		if(strcmp(name, "reverse") == 0) {
nuclear@2: 			rng->cmode = val;
nuclear@2: 		} else if(strcmp(name, "rate") == 0) {
nuclear@2: 			rng->rate = val;
nuclear@2: 		} else if(strcmp(name, "low") == 0) {
nuclear@2: 			rng->low = val;
nuclear@2: 		} else if(strcmp(name, "high") == 0) {
nuclear@2: 			rng->high = val;
nuclear@2: 		} else {
nuclear@2: 			fprintf(stderr, "invalid attribute %s in cycles range\n", name);
nuclear@2: 			return -1;
nuclear@2: 		}
nuclear@2: 
nuclear@2: 		if(nextc == ',') {
nuclear@2: 			next_token(fp);
nuclear@2: 		}
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	EXPECT(fp, '}');
nuclear@2: 	return 0;
nuclear@2: }
nuclear@2: 
nuclear@2: static int cycles(FILE *fp, struct image *img)
nuclear@2: {
nuclear@2: 	struct colrange *list = 0, *rng;
nuclear@2: 
nuclear@2: 	EXPECT(fp, '[');
nuclear@2: 
nuclear@2: 	img->num_ranges = 0;
nuclear@2: 	while(nextc == '{') {
nuclear@2: 		if(!(rng = malloc(sizeof *rng))) {
nuclear@2: 			perror("failed to allocate color range");
nuclear@2: 			goto err;
nuclear@2: 		}
nuclear@2: 		if(crange(fp, rng) == -1) {
nuclear@2: 			free(rng);
nuclear@2: 			goto err;
nuclear@2: 		}
nuclear@2: 		if(rng->low != rng->high && rng->rate > 0) {
nuclear@2: 			rng->next = list;
nuclear@2: 			list = rng;
nuclear@2: 			++img->num_ranges;
nuclear@2: 		} else {
nuclear@2: 			free(rng);
nuclear@2: 		}
nuclear@2: 
nuclear@2: 		if(nextc == ',') {
nuclear@2: 			next_token(fp);	/* eat the comma */
nuclear@2: 		}
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	img->range = list;
nuclear@2: 
nuclear@2: 	if(!expect(fp, ']')) {
nuclear@2: 		fprintf(stderr, "cycles: missing closing bracket\n");
nuclear@2: 		goto err;
nuclear@2: 	}
nuclear@2: 	return 0;
nuclear@2: 
nuclear@2: err:
nuclear@2: 	while(list) {
nuclear@2: 		rng = list;
nuclear@2: 		list = list->next;
nuclear@2: 		free(rng);
nuclear@2: 	}
nuclear@2: 	img->num_ranges = 0;
nuclear@2: 	return -1;
nuclear@2: }
nuclear@2: 
nuclear@2: static int pixels(FILE *fp, struct image *img)
nuclear@2: {
nuclear@2: 	int tok, num_pixels;
nuclear@2: 	unsigned char *pptr;
nuclear@2: 
nuclear@2: 	if(img->width <= 0 || img->height <= 0) {
nuclear@2: 		fprintf(stderr, "pixel block found before defining the image dimensions!\n");
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 	num_pixels = img->width * img->height;
nuclear@2: 	if(!(img->pixels = malloc(num_pixels))) {
nuclear@2: 		perror("failed to allocate pixels");
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 	pptr = img->pixels;
nuclear@2: 
nuclear@2: 	EXPECT(fp, '[');
nuclear@2: 
nuclear@2: 	while((tok = next_token(fp)) == TOKEN_NUM) {
nuclear@2: 		if(pptr - img->pixels >= num_pixels) {
nuclear@2: 			pptr = 0;
nuclear@2: 			fprintf(stderr, "more pixel data provided than the specified image dimensions\n");
nuclear@2: 		}
nuclear@2: 		if(!pptr) continue;
nuclear@2: 		*pptr++ = atoi(token);
nuclear@2: 
nuclear@2: 		if(nextc == ',') {
nuclear@2: 			next_token(fp);	/* eat comma */
nuclear@2: 		}
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	if(tok != ']') {
nuclear@2: 		printf("pixels: missing closing bracket\n");
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 	return 0;
nuclear@2: }
nuclear@2: 
nuclear@2: static int attribute(FILE *fp, struct image *img)
nuclear@2: {
nuclear@2: 	char *attr_name;
nuclear@2: 
nuclear@2: 	if(!expect(fp, TOKEN_NAME)) {
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 	attr_name = alloca(strlen(token) + 1);
nuclear@2: 	strcpy(attr_name, token);
nuclear@2: 
nuclear@2: 	if(!expect(fp, ':')) {
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	if(strcmp(attr_name, "filename") == 0) {
nuclear@2: 		if(!expect(fp, TOKEN_STR)) {
nuclear@2: 			fprintf(stderr, "attribute: filename should be a string\n");
nuclear@2: 			return -1;
nuclear@2: 		}
nuclear@2: 
nuclear@2: 	} else if(strcmp(attr_name, "width") == 0 || strcmp(attr_name, "height") == 0) {
nuclear@2: 		int *dst = attr_name[0] == 'w' ? &img->width : &img->height;
nuclear@2: 		if(!expect(fp, TOKEN_NUM)) {
nuclear@2: 			fprintf(stderr, "attribute: %s should be a number\n", attr_name);
nuclear@2: 			return -1;
nuclear@2: 		}
nuclear@2: 		*dst = atoi(token);
nuclear@2: 
nuclear@2: 	} else if(strcmp(attr_name, "colors") == 0) {
nuclear@2: 		if(palette(fp, img) == -1) {
nuclear@2: 			fprintf(stderr, "attribute: colors should be a palette\n");
nuclear@2: 			return -1;
nuclear@2: 		}
nuclear@2: 
nuclear@2: 	} else if(strcmp(attr_name, "cycles") == 0) {
nuclear@2: 		if(cycles(fp, img) == -1) {
nuclear@2: 			fprintf(stderr, "attribute: cycles should be a list of palranges\n");
nuclear@2: 			return -1;
nuclear@2: 		}
nuclear@2: 
nuclear@2: 	} else if(strcmp(attr_name, "pixels") == 0) {
nuclear@2: 		if(pixels(fp, img) == -1) {
nuclear@2: 			fprintf(stderr, "attribute: pixels should be a list of indices\n");
nuclear@2: 			return -1;
nuclear@2: 		}
nuclear@2: 
nuclear@2: 	} else {
nuclear@2: 		fprintf(stderr, "unknown attribute: %s\n", attr_name);
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 	return 0;
nuclear@2: }
nuclear@2: 
nuclear@2: static int image_block(FILE *fp, struct image *img)
nuclear@2: {
nuclear@2: 	EXPECT(fp, '{');
nuclear@2: 
nuclear@2: 	img->width = img->height = -1;
nuclear@2: 	img->bpp = 8;
nuclear@2: 
nuclear@2: 	while(attribute(fp, img) != -1) {
nuclear@2: 		if(nextc == ',') {
nuclear@2: 			next_token(fp);	/* eat comma */
nuclear@2: 		}
nuclear@2: 	}
nuclear@2: 	return 0;
nuclear@2: }