nuclear@2: /*
nuclear@2: colcycle - color cycling image viewer
nuclear@2: Copyright (C) 2016  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 <math.h>
nuclear@2: #include <errno.h>
nuclear@2: #ifdef __WATCOMC__
nuclear@2: #include "inttypes.h"
nuclear@2: #include <direct.h>
nuclear@2: #else
nuclear@2: #include <inttypes.h>
nuclear@2: #include <dirent.h>
nuclear@2: #endif
nuclear@2: #include <sys/stat.h>
nuclear@2: #include "app.h"
nuclear@2: #include "image.h"
nuclear@2: 
nuclear@2: /* define this if the assembly 32->64bit multiplication in cycle_offset doesn't
nuclear@2:  * work for you for some reason, and you wish to compile the floating point
nuclear@2:  * version of the time calculation.
nuclear@2:  */
nuclear@2: #undef NO_ASM
nuclear@2: 
nuclear@2: #if defined(NO_ASM) || (!defined(__i386__) && !defined(__x86_64__) && !defined(__X86__))
nuclear@2: #define USE_FLOAT
nuclear@2: #endif
nuclear@2: 
nuclear@2: 
nuclear@2: #ifndef M_PI
nuclear@2: #define M_PI 3.141593
nuclear@2: #endif
nuclear@2: 
nuclear@2: struct ss_node {
nuclear@2: 	char *path;
nuclear@2: 	struct image *img;
nuclear@2: 	struct ss_node *next;
nuclear@2: };
nuclear@2: 
nuclear@2: static void set_image_palette(struct image *img);
nuclear@2: static void show_image(struct image *img, long time_msec);
nuclear@2: static int load_slideshow(const char *path);
nuclear@2: static int load_slide(void);
nuclear@2: 
nuclear@2: int fbwidth, fbheight;
nuclear@2: unsigned char *fbpixels;
nuclear@2: 
nuclear@2: static struct image *img;
nuclear@2: static int blend = 1;
nuclear@2: static int fade_dir;
nuclear@2: static unsigned long fade_start, fade_dur = 600;
nuclear@2: static int change_pending;
nuclear@2: static unsigned long showing_since, show_time = 15000;
nuclear@2: 
nuclear@2: static struct ss_node *sslist;
nuclear@2: 
nuclear@2: extern long upd_interval;
nuclear@2: 
nuclear@2: int colc_init(int argc, char **argv)
nuclear@2: {
nuclear@2: 	if(argv[1]) {
nuclear@2: 		struct stat st;
nuclear@2: 
nuclear@2: 		if(stat(argv[1], &st) == -1) {
nuclear@2: 			fprintf(stderr, "failed to stat path: %s\n", argv[1]);
nuclear@2: 			return -1;
nuclear@2: 		}
nuclear@2: 
nuclear@2: 		if(S_ISDIR(st.st_mode)) {
nuclear@2: 			if(load_slideshow(argv[1]) == -1) {
nuclear@2: 				fprintf(stderr, "failed to load slideshow in dir: %s\n", argv[1]);
nuclear@2: 				return -1;
nuclear@2: 			}
nuclear@2: 			if(load_slide() == -1) {
nuclear@2: 				return -1;
nuclear@2: 			}
nuclear@2: 
nuclear@2: 		} else {
nuclear@2: 			if(!(img = malloc(sizeof *img))) {
nuclear@2: 				perror("failed to allocate image structure");
nuclear@2: 				return -1;
nuclear@2: 			}
nuclear@2: 			if(colc_load_image(img, argv[1]) == -1) {
nuclear@2: 				fprintf(stderr, "failed to load image: %s\n", argv[1]);
nuclear@2: 				return -1;
nuclear@2: 			}
nuclear@2: 		}
nuclear@2: 	} else {
nuclear@2: 		if(!(img = malloc(sizeof *img))) {
nuclear@2: 			perror("failed to allocate image structure");
nuclear@2: 			return -1;
nuclear@2: 		}
nuclear@2: 		if(colc_gen_test_image(img) == -1) {
nuclear@2: 			fprintf(stderr, "failed to generate test image\n");
nuclear@2: 			return -1;
nuclear@2: 		}
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	set_image_palette(img);
nuclear@2: 	show_image(img, 0);
nuclear@2: 	return 0;
nuclear@2: }
nuclear@2: 
nuclear@2: void colc_cleanup(void)
nuclear@2: {
nuclear@2: 	if(sslist) {
nuclear@2: 		struct ss_node *start = sslist;
nuclear@2: 		sslist = sslist->next;
nuclear@2: 		start->next = 0;	/* break the circle */
nuclear@2: 
nuclear@2: 		while(sslist) {
nuclear@2: 			struct ss_node *node = sslist;
nuclear@2: 			sslist = sslist->next;
nuclear@2: 			colc_destroy_image(node->img);
nuclear@2: 			free(node->path);
nuclear@2: 			free(node);
nuclear@2: 		}
nuclear@2: 
nuclear@2: 	} else {
nuclear@2: 		colc_destroy_image(img);
nuclear@2: 		free(img);
nuclear@2: 	}
nuclear@2: }
nuclear@2: 
nuclear@2: /* tx is fixed point with 10 bits decimal */
nuclear@2: static void palfade(int dir, long tx)
nuclear@2: {
nuclear@2: 	int i;
nuclear@2: 
nuclear@2: 	if(!img) return;
nuclear@2: 
nuclear@2: 	if(dir == -1) {
nuclear@2: 		tx = 1024 - tx;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	for(i=0; i<256; i++) {
nuclear@2: 		int r = (img->palette[i].r * tx) >> 10;
nuclear@2: 		int g = (img->palette[i].g * tx) >> 10;
nuclear@2: 		int b = (img->palette[i].b * tx) >> 10;
nuclear@2: 		set_palette(i, r, g, b);
nuclear@2: 	}
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: /* modes:
nuclear@2:  *  1. normal
nuclear@2:  *  2. reverse
nuclear@2:  *  3. ping-pong
nuclear@2:  *  4. sine -> [0, rsize/2]
nuclear@2:  *  5. sine -> [0, rsize]
nuclear@2:  *
nuclear@2:  * returns: offset in 24.8 fixed point
nuclear@2:  */
nuclear@2: #ifdef USE_FLOAT
nuclear@2: static int32_t cycle_offset(enum cycle_mode mode, int32_t rate, int32_t rsize, int32_t msec)
nuclear@2: {
nuclear@2: 	float offs;
nuclear@2: 	float tm = (rate / 280.0) * (float)msec / 1000.0;
nuclear@2: 
nuclear@2: 	switch(mode) {
nuclear@2: 	case CYCLE_PINGPONG:
nuclear@2: 		offs = fmod(tm, (float)(rsize * 2));
nuclear@2: 		if(offs >= rsize) offs = (rsize * 2) - offs;
nuclear@2: 		break;
nuclear@2: 
nuclear@2: 	case CYCLE_SINE:
nuclear@2: 	case CYCLE_SINE_HALF:
nuclear@2: 		{
nuclear@2: 			float x = fmod(tm, (float)rsize);
nuclear@2: 			offs = sin((x * M_PI * 2.0) / (float)rsize) + 1.0;
nuclear@2: 			offs *= rsize / (mode == CYCLE_SINE_HALF ? 4.0f : 2.0f);
nuclear@2: 		}
nuclear@2: 		break;
nuclear@2: 
nuclear@2: 	default:	/* normal or reverse */
nuclear@2: 		offs = tm;
nuclear@2: 	}
nuclear@2: 	return (int32_t)(offs * 256.0);
nuclear@2: }
nuclear@2: 
nuclear@2: #else	/* fixed point variant for specific platforms (currently x86) */
nuclear@2: 
nuclear@2: #ifdef __GNUC__
nuclear@2: #define CALC_TIME(res, anim_rate, time_msec) \
nuclear@2: 	asm volatile ( \
nuclear@2: 		"\n\tmull %1"	/* edx:eax <- eax(rate << 8) * msec */ \
nuclear@2: 		"\n\tmovl $280000, %%ebx" \
nuclear@2: 		"\n\tdivl %%ebx"	/* eax <- edx:eax / ebx */ \
nuclear@2: 		: "=a" (res) \
nuclear@2: 		: "g" ((uint32_t)(time_msec)), "a" ((anim_rate) << 8) \
nuclear@2: 		: "ebx", "edx" )
nuclear@2: #endif	/* __GNUC__ */
nuclear@2: 
nuclear@2: #ifdef __WATCOMC__
nuclear@2: #define CALC_TIME(res, anim_rate, time_msec) \
nuclear@2: 	(res) = calc_time_offset(anim_rate, time_msec)
nuclear@2: 
nuclear@2: int32_t calc_time_offset(int32_t anim_rate, int32_t time_msec);
nuclear@2: #pragma aux calc_time_offset = \
nuclear@2: 		"shl eax, 8" /* eax(rate) <<= 8 convert to 24.8 fixed point */ \
nuclear@2: 		"mul ebx"	/* edx:eax <- eax(rate<<8) * ebx(msec) */ \
nuclear@2: 		"mov ebx, 280000" \
nuclear@2: 		"div ebx"	/* eax <- edx:eax / ebx */ \
nuclear@2: 		modify [eax ebx ecx] \
nuclear@2: 		value [eax] \
nuclear@2: 		parm [eax] [ebx];
nuclear@2: #endif	/* __WATCOMC__ */
nuclear@2: 
nuclear@2: static int32_t cycle_offset(enum cycle_mode mode, int32_t rate, int32_t rsize, int32_t msec)
nuclear@2: {
nuclear@2: 	int32_t offs, tm;
nuclear@2: 
nuclear@2: 	CALC_TIME(tm, rate, msec);
nuclear@2: 
nuclear@2: 	switch(mode) {
nuclear@2: 	case CYCLE_PINGPONG:
nuclear@2: 		rsize <<= 8;	/* rsize -> 24.8 fixed point */
nuclear@2: 		offs = tm % (rsize * 2);
nuclear@2: 		if(offs > rsize) offs = (rsize * 2) - offs;
nuclear@2: 		rsize >>= 8;	/* back to 32.0 */
nuclear@2: 		break;
nuclear@2: 
nuclear@2: 	case CYCLE_SINE:
nuclear@2: 	case CYCLE_SINE_HALF:
nuclear@2: 		{
nuclear@2: 			float t = (float)tm / 256.0;	/* convert fixed24.8 -> float */
nuclear@2: 			float x = fmod(t, (float)(rsize * 2));
nuclear@2: 			float foffs = sin((x * M_PI * 2.0) / (float)rsize) + 1.0;
nuclear@2: 			if(mode == CYCLE_SINE_HALF) {
nuclear@2: 				foffs *= rsize / 4.0;
nuclear@2: 			} else {
nuclear@2: 				foffs *= rsize / 2.0;
nuclear@2: 			}
nuclear@2: 			offs = (int32_t)(foffs * 256.0);	/* convert float -> fixed24.8 */
nuclear@2: 		}
nuclear@2: 		break;
nuclear@2: 
nuclear@2: 	default:	/* normal or reverse */
nuclear@2: 		offs = tm;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	return offs;
nuclear@2: }
nuclear@2: #endif	/* USE_FLOAT */
nuclear@2: 
nuclear@2: #define LERP_FIXED_T(a, b, xt) ((((a) << 8) + ((b) - (a)) * (xt)) >> 8)
nuclear@2: 
nuclear@2: void colc_draw(long time_msec)
nuclear@2: {
nuclear@2: 	int i, j;
nuclear@2: 
nuclear@2: 	if(!img) return;
nuclear@2: 
nuclear@2: 	if(sslist) {
nuclear@2: 		/* if there is a slideshow list of images, handle switching with fades between them */
nuclear@2: 		if(!fade_dir && (change_pending || time_msec - showing_since > show_time)) {
nuclear@2: 			fade_dir = -1;
nuclear@2: 			fade_start = time_msec;
nuclear@2: 			change_pending = 0;
nuclear@2: 		}
nuclear@2: 
nuclear@2: 		if(fade_dir) {
nuclear@2: 			unsigned long dt = time_msec - fade_start;
nuclear@2: 
nuclear@2: 			if(dt >= fade_dur) {
nuclear@2: 				if(fade_dir == -1) {
nuclear@2: 					sslist = sslist->next;
nuclear@2: 					if(load_slide() == -1) {
nuclear@2: 						return;
nuclear@2: 					}
nuclear@2: 					show_image(img, time_msec);
nuclear@2: 					fade_dir = 1;
nuclear@2: 					time_msec = fade_start = time_msec;
nuclear@2: 					dt = 0;
nuclear@2: 				} else {
nuclear@2: 					set_image_palette(img);
nuclear@2: 					fade_dir = 0;
nuclear@2: 				}
nuclear@2: 			}
nuclear@2: 
nuclear@2: 			if(fade_dir) {
nuclear@2: 				long tx = ((long)dt << 10) / fade_dur;
nuclear@2: 				palfade(fade_dir, tx);
nuclear@2: 			}
nuclear@2: 			showing_since = time_msec;
nuclear@2: 			return;
nuclear@2: 		}
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	/* for each cycling range in the image ... */
nuclear@2: 	for(i=0; i<img->num_ranges; i++) {
nuclear@2: 		int32_t offs, rsize, ioffs;
nuclear@2: 		int rev;
nuclear@2: 
nuclear@2: 		if(!img->range[i].rate) continue;
nuclear@2: 		rsize = img->range[i].high - img->range[i].low + 1;
nuclear@2: 
nuclear@2: 		offs = cycle_offset(img->range[i].cmode, img->range[i].rate, rsize, time_msec);
nuclear@2: 
nuclear@2: 		ioffs = (offs >> 8) % rsize;
nuclear@2: 
nuclear@2: 		/* reverse when rev is 2 */
nuclear@2: 		rev = img->range[i].cmode == CYCLE_REVERSE ? 1 : 0;
nuclear@2: 
nuclear@2: 		for(j=0; j<rsize; j++) {
nuclear@2: 			int pidx, to, next;
nuclear@2: 
nuclear@2: 			pidx = j + img->range[i].low;
nuclear@2: 
nuclear@2: 			if(rev) {
nuclear@2: 				to = (j + ioffs) % rsize;
nuclear@2: 				next = (to + 1) % rsize;
nuclear@2: 			} else {
nuclear@2: 				if((to = (j - ioffs) % rsize) < 0) {
nuclear@2: 					to += rsize;
nuclear@2: 				}
nuclear@2: 				if((next = to - 1) < 0) {
nuclear@2: 					next += rsize;
nuclear@2: 				}
nuclear@2: 			}
nuclear@2: 			to += img->range[i].low;
nuclear@2: 
nuclear@2: 			if(blend) {
nuclear@2: 				int r, g, b;
nuclear@2: 				int32_t frac_offs = offs & 0xff;
nuclear@2: 
nuclear@2: 				next += img->range[i].low;
nuclear@2: 
nuclear@2: 				r = LERP_FIXED_T(img->palette[to].r, img->palette[next].r, frac_offs);
nuclear@2: 				g = LERP_FIXED_T(img->palette[to].g, img->palette[next].g, frac_offs);
nuclear@2: 				b = LERP_FIXED_T(img->palette[to].b, img->palette[next].b, frac_offs);
nuclear@2: 
nuclear@2: 				set_palette(pidx, r, g, b);
nuclear@2: 			} else {
nuclear@2: 				set_palette(pidx, img->palette[to].r, img->palette[to].g, img->palette[to].b);
nuclear@2: 			}
nuclear@2: 		}
nuclear@2: 	}
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: static void set_image_palette(struct image *img)
nuclear@2: {
nuclear@2: 	int i;
nuclear@2: 	for(i=0; i<256; i++) {
nuclear@2: 		set_palette(i, img->palette[i].r, img->palette[i].g, img->palette[i].b);
nuclear@2: 	}
nuclear@2: }
nuclear@2: 
nuclear@2: static void show_image(struct image *img, long time_msec)
nuclear@2: {
nuclear@2: 	int i, j;
nuclear@2: 	unsigned char *dptr;
nuclear@2: 	unsigned int max_rate = 0;
nuclear@2: 
nuclear@2: 	resize(img->width, img->height);
nuclear@2: 
nuclear@2: 	dptr = fbpixels;
nuclear@2: 	for(i=0; i<fbheight; i++) {
nuclear@2: 		for(j=0; j<fbwidth; j++) {
nuclear@2: 			unsigned char c = 0;
nuclear@2: 			if(i < img->height && j < img->width) {
nuclear@2: 				c = img->pixels[i * img->width + j];
nuclear@2: 			}
nuclear@2: 			*dptr++ = c;
nuclear@2: 		}
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	showing_since = time_msec;
nuclear@2: 
nuclear@2: 	for(i=0; i<img->num_ranges; i++) {
nuclear@2: 		if(img->range[i].rate > max_rate) {
nuclear@2: 			max_rate = img->range[i].rate;
nuclear@2: 		}
nuclear@2: 	}
nuclear@2: 	upd_interval = max_rate * 10;
nuclear@2: }
nuclear@2: 
nuclear@2: static int load_slideshow(const char *path)
nuclear@2: {
nuclear@2: 	DIR *dir;
nuclear@2: 	struct dirent *dent;
nuclear@2: 	struct ss_node *head = 0, *tail = 0, *node;
nuclear@2: 
nuclear@2: 	if(!(dir = opendir(path))) {
nuclear@2: 		fprintf(stderr, "failed to open directory: %s: %s\n", path, strerror(errno));
nuclear@2: 		return -1;
nuclear@2: 	}
nuclear@2: 
nuclear@2: 	while((dent = readdir(dir))) {
nuclear@2: 		int sz;
nuclear@2: 
nuclear@2: 		if(strcmp(dent->d_name, ".") == 0 || strcmp(dent->d_name, "..") == 0) {
nuclear@2: 			continue;
nuclear@2: 		}
nuclear@2: 		sz = strlen(path) + strlen(dent->d_name) + 1;	/* +1 for a slash */
nuclear@2: 
nuclear@2: 		if(!(node = malloc(sizeof *node))) {
nuclear@2: 			perror("failed to allocate slideshow node");
nuclear@2: 			goto err;
nuclear@2: 		}
nuclear@2: 		if(!(node->path = malloc(sz + 1))) {
nuclear@2: 			perror("failed to allocate image path");
nuclear@2: 			free(node);
nuclear@2: 			goto err;
nuclear@2: 		}
nuclear@2: 		sprintf(node->path, "%s/%s", path, dent->d_name);
nuclear@2: 		node->img = 0;
nuclear@2: 		node->next = 0;
nuclear@2: 
nuclear@2: 		if(head) {
nuclear@2: 			tail->next = node;
nuclear@2: 			tail = node;
nuclear@2: 		} else {
nuclear@2: 			head = tail = node;
nuclear@2: 		}
nuclear@2: 	}
nuclear@2: 	closedir(dir);
nuclear@2: 
nuclear@2: 	sslist = head;
nuclear@2: 	tail->next = head;	/* make circular */
nuclear@2: 	return 0;
nuclear@2: 
nuclear@2: err:
nuclear@2: 	closedir(dir);
nuclear@2: 	while(head) {
nuclear@2: 		node = head;
nuclear@2: 		head = head->next;
nuclear@2: 		free(node->path);
nuclear@2: 		free(node);
nuclear@2: 	}
nuclear@2: 	return -1;
nuclear@2: }
nuclear@2: 
nuclear@2: static int load_slide(void)
nuclear@2: {
nuclear@2: 	struct ss_node *start = sslist;
nuclear@2: 
nuclear@2: 	img = 0;
nuclear@2: 	do {
nuclear@2: 		if(sslist->path) {
nuclear@2: 			if(!sslist->img) {
nuclear@2: 				if(!(sslist->img = malloc(sizeof *sslist->img))) {
nuclear@2: 					perror("failed to allocate image structure");
nuclear@2: 					return -1;
nuclear@2: 				}
nuclear@2: 				if(colc_load_image(sslist->img, sslist->path) == -1) {
nuclear@2: 					fprintf(stderr, "failed to load image: %s\n", sslist->path);
nuclear@2: 					free(sslist->path);
nuclear@2: 					sslist->path = 0;
nuclear@2: 					free(sslist->img);
nuclear@2: 					sslist->img = 0;
nuclear@2: 				}
nuclear@2: 			}
nuclear@2: 			img = sslist->img;
nuclear@2: 		}
nuclear@2: 
nuclear@2: 		sslist = sslist->next;
nuclear@2: 	} while(!img && sslist != start);
nuclear@2: 
nuclear@2: 	return img ? 0 : -1;
nuclear@2: }