src/third-party/libpng/contrib/gregbook/rpng2-win.c (view raw)
1/*---------------------------------------------------------------------------
2
3 rpng2 - progressive-model PNG display program rpng2-win.c
4
5 This program decodes and displays PNG files progressively, as if it were
6 a web browser (though the front end is only set up to read from files).
7 It supports gamma correction, user-specified background colors, and user-
8 specified background patterns (for transparent images). This version is
9 for 32-bit Windows; it may compile under 16-bit Windows with a little
10 tweaking (or maybe not). Thanks to Adam Costello and Pieter S. van der
11 Meulen for the "diamond" and "radial waves" patterns, respectively.
12
13 to do (someday, maybe):
14 - handle quoted command-line args (especially filenames with spaces)
15 - finish resizable checkerboard-gradient (sizes 4-128?)
16 - use %.1023s to simplify truncation of title-bar string?
17 - have minimum window width: oh well
18
19 ---------------------------------------------------------------------------
20
21 Changelog:
22 - 1.01: initial public release
23 - 1.02: fixed cut-and-paste error in usage screen (oops...)
24 - 1.03: modified to allow abbreviated options
25 - 1.04: removed bogus extra argument from usage fprintf() [Glenn R-P?];
26 fixed command-line parsing bug
27 - 1.10: enabled "message window"/console (thanks to David Geldreich)
28 - 1.20: added runtime MMX-enabling/disabling and new -mmx* options
29 - 1.21: made minor tweak to usage screen to fit within 25-line console
30 - 1.22: added AMD64/EM64T support (__x86_64__)
31 - 2.00: dual-licensed (added GNU GPL)
32 - 2.01: fixed 64-bit typo in readpng2.c
33 - 2.02: fixed improper display of usage screen on PNG error(s); fixed
34 unexpected-EOF and file-read-error cases
35 - 2.03: removed runtime MMX-enabling/disabling and obsolete -mmx* options
36 - 2.04:
37 (GR-P)
38
39 ---------------------------------------------------------------------------
40
41 Copyright (c) 1998-2008 Greg Roelofs. All rights reserved.
42
43 This software is provided "as is," without warranty of any kind,
44 express or implied. In no event shall the author or contributors
45 be held liable for any damages arising in any way from the use of
46 this software.
47
48 The contents of this file are DUAL-LICENSED. You may modify and/or
49 redistribute this software according to the terms of one of the
50 following two licenses (at your option):
51
52
53 LICENSE 1 ("BSD-like with advertising clause"):
54
55 Permission is granted to anyone to use this software for any purpose,
56 including commercial applications, and to alter it and redistribute
57 it freely, subject to the following restrictions:
58
59 1. Redistributions of source code must retain the above copyright
60 notice, disclaimer, and this list of conditions.
61 2. Redistributions in binary form must reproduce the above copyright
62 notice, disclaimer, and this list of conditions in the documenta-
63 tion and/or other materials provided with the distribution.
64 3. All advertising materials mentioning features or use of this
65 software must display the following acknowledgment:
66
67 This product includes software developed by Greg Roelofs
68 and contributors for the book, "PNG: The Definitive Guide,"
69 published by O'Reilly and Associates.
70
71
72 LICENSE 2 (GNU GPL v2 or later):
73
74 This program is free software; you can redistribute it and/or modify
75 it under the terms of the GNU General Public License as published by
76 the Free Software Foundation; either version 2 of the License, or
77 (at your option) any later version.
78
79 This program is distributed in the hope that it will be useful,
80 but WITHOUT ANY WARRANTY; without even the implied warranty of
81 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
82 GNU General Public License for more details.
83
84 You should have received a copy of the GNU General Public License
85 along with this program; if not, write to the Free Software Foundation,
86 Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
87
88 ---------------------------------------------------------------------------*/
89
90#define PROGNAME "rpng2-win"
91#define LONGNAME "Progressive PNG Viewer for Windows"
92#define VERSION "2.02 of 16 March 2008"
93
94#include <stdio.h>
95#include <stdlib.h>
96#include <string.h>
97#include <setjmp.h> /* for jmpbuf declaration in readpng2.h */
98#include <time.h>
99#include <math.h> /* only for PvdM background code */
100#include <windows.h>
101#ifdef __CYGWIN__
102/* getch replacement. Turns out, we don't really need this,
103 * but leave it here if we ever enable any of the uses of
104 * _getch in the main code
105 */
106#include <unistd.h>
107#include <termio.h>
108#include <sys/ioctl.h>
109int repl_getch( void )
110{
111 char ch;
112 int fd = fileno(stdin);
113 struct termio old_tty, new_tty;
114
115 ioctl(fd, TCGETA, &old_tty);
116 new_tty = old_tty;
117 new_tty.c_lflag &= ~(ICANON | ECHO | ISIG);
118 ioctl(fd, TCSETA, &new_tty);
119 fread(&ch, 1, sizeof(ch), stdin);
120 ioctl(fd, TCSETA, &old_tty);
121
122 return ch;
123}
124#define _getch repl_getch
125#else
126#include <conio.h> /* only for _getch() */
127#endif
128
129/* all for PvdM background code: */
130#ifndef PI
131# define PI 3.141592653589793238
132#endif
133#define PI_2 (PI*0.5)
134#define INV_PI_360 (360.0 / PI)
135#define MAX(a,b) (a>b?a:b)
136#define MIN(a,b) (a<b?a:b)
137#define CLIP(a,min,max) MAX(min,MIN((a),max))
138#define ABS(a) ((a)<0?-(a):(a))
139#define CLIP8P(c) MAX(0,(MIN((c),255))) /* 8-bit pos. integer (uch) */
140#define ROUNDF(f) ((int)(f + 0.5))
141
142#define rgb1_max bg_freq
143#define rgb1_min bg_gray
144#define rgb2_max bg_bsat
145#define rgb2_min bg_brot
146
147/* #define DEBUG */ /* this enables the Trace() macros */
148
149#include "readpng2.h" /* typedefs, common macros, readpng2 prototypes */
150
151
152/* could just include png.h, but this macro is the only thing we need
153 * (name and typedefs changed to local versions); note that side effects
154 * only happen with alpha (which could easily be avoided with
155 * "ush acopy = (alpha);") */
156
157#define alpha_composite(composite, fg, alpha, bg) { \
158 ush temp = ((ush)(fg)*(ush)(alpha) + \
159 (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128); \
160 (composite) = (uch)((temp + (temp >> 8)) >> 8); \
161}
162
163
164#define INBUFSIZE 4096 /* with pseudo-timing on (1 sec delay/block), this
165 * block size corresponds roughly to a download
166 * speed 10% faster than theoretical 33.6K maximum
167 * (assuming 8 data bits, 1 stop bit and no other
168 * overhead) */
169
170/* local prototypes */
171static void rpng2_win_init(void);
172static int rpng2_win_create_window(void);
173static int rpng2_win_load_bg_image(void);
174static void rpng2_win_display_row(ulg row);
175static void rpng2_win_finish_display(void);
176static void rpng2_win_cleanup(void);
177LRESULT CALLBACK rpng2_win_wndproc(HWND, UINT, WPARAM, LPARAM);
178
179
180static char titlebar[1024];
181static char *progname = PROGNAME;
182static char *appname = LONGNAME;
183static char *filename;
184static FILE *infile;
185
186static mainprog_info rpng2_info;
187
188static uch inbuf[INBUFSIZE];
189static int incount;
190
191static int pat = 6; /* must be less than num_bgpat */
192static int bg_image = 0;
193static int bgscale = 16;
194static ulg bg_rowbytes;
195static uch *bg_data;
196
197static struct rgb_color {
198 uch r, g, b;
199} rgb[] = {
200 { 0, 0, 0}, /* 0: black */
201 {255, 255, 255}, /* 1: white */
202 {173, 132, 57}, /* 2: tan */
203 { 64, 132, 0}, /* 3: medium green */
204 {189, 117, 1}, /* 4: gold */
205 {253, 249, 1}, /* 5: yellow */
206 { 0, 0, 255}, /* 6: blue */
207 { 0, 0, 120}, /* 7: medium blue */
208 {255, 0, 255}, /* 8: magenta */
209 { 64, 0, 64}, /* 9: dark magenta */
210 {255, 0, 0}, /* 10: red */
211 { 64, 0, 0}, /* 11: dark red */
212 {255, 127, 0}, /* 12: orange */
213 {192, 96, 0}, /* 13: darker orange */
214 { 24, 60, 0}, /* 14: dark green-yellow */
215 { 85, 125, 200} /* 15: ice blue */
216};
217/* not used for now, but should be for error-checking:
218static int num_rgb = sizeof(rgb) / sizeof(struct rgb_color);
219 */
220
221/*
222 This whole struct is a fairly cheesy way to keep the number of
223 command-line options to a minimum. The radial-waves background
224 type is a particularly poor fit to the integer elements of the
225 struct...but a few macros and a little fixed-point math will do
226 wonders for ya.
227
228 type bits:
229 F E D C B A 9 8 7 6 5 4 3 2 1 0
230 | | | | |
231 | | +-+-+-- 0 = sharp-edged checkerboard
232 | | 1 = soft diamonds
233 | | 2 = radial waves
234 | | 3-7 = undefined
235 | +-- gradient #2 inverted?
236 +-- alternating columns inverted?
237 */
238static struct background_pattern {
239 ush type;
240 int rgb1_max, rgb1_min; /* or bg_freq, bg_gray */
241 int rgb2_max, rgb2_min; /* or bg_bsat, bg_brot (both scaled by 10)*/
242} bg[] = {
243 {0+8, 2,0, 1,15}, /* checkered: tan/black vs. white/ice blue */
244 {0+24, 2,0, 1,0}, /* checkered: tan/black vs. white/black */
245 {0+8, 4,5, 0,2}, /* checkered: gold/yellow vs. black/tan */
246 {0+8, 4,5, 0,6}, /* checkered: gold/yellow vs. black/blue */
247 {0, 7,0, 8,9}, /* checkered: deep blue/black vs. magenta */
248 {0+8, 13,0, 5,14}, /* checkered: orange/black vs. yellow */
249 {0+8, 12,0, 10,11}, /* checkered: orange/black vs. red */
250 {1, 7,0, 8,0}, /* diamonds: deep blue/black vs. magenta */
251 {1, 12,0, 11,0}, /* diamonds: orange vs. dark red */
252 {1, 10,0, 7,0}, /* diamonds: red vs. medium blue */
253 {1, 4,0, 5,0}, /* diamonds: gold vs. yellow */
254 {1, 3,0, 0,0}, /* diamonds: medium green vs. black */
255 {2, 16, 100, 20, 0}, /* radial: ~hard radial color-beams */
256 {2, 18, 100, 10, 2}, /* radial: soft, curved radial color-beams */
257 {2, 16, 256, 100, 250}, /* radial: very tight spiral */
258 {2, 10000, 256, 11, 0} /* radial: dipole-moire' (almost fractal) */
259};
260static int num_bgpat = sizeof(bg) / sizeof(struct background_pattern);
261
262
263/* Windows-specific global variables (could go in struct, but messy...) */
264static ulg wimage_rowbytes;
265static uch *dib;
266static uch *wimage_data;
267static BITMAPINFOHEADER *bmih;
268
269static HWND global_hwnd;
270static HINSTANCE global_hInst;
271static int global_showmode;
272
273
274
275
276int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
277{
278 char *args[1024]; /* arbitrary limit, but should suffice */
279 char **argv = args;
280 char *p, *q, *bgstr = NULL;
281 int argc = 0;
282 int rc, alen, flen;
283 int error = 0;
284 int timing = FALSE;
285 int have_bg = FALSE;
286 double LUT_exponent; /* just the lookup table */
287 double CRT_exponent = 2.2; /* just the monitor */
288 double default_display_exponent; /* whole display system */
289 MSG msg;
290
291
292 /* First initialize a few things, just to be sure--memset takes care of
293 * default background color (black), booleans (FALSE), pointers (NULL),
294 * etc. */
295
296 global_hInst = hInst;
297 global_showmode = showmode;
298 filename = (char *)NULL;
299 memset(&rpng2_info, 0, sizeof(mainprog_info));
300
301#ifndef __CYGWIN__
302 /* Next reenable console output, which normally goes to the bit bucket
303 * for windowed apps. Closing the console window will terminate the
304 * app. Thanks to David.Geldreich@realviz.com for supplying the magical
305 * incantation. */
306
307 AllocConsole();
308 freopen("CONOUT$", "a", stderr);
309 freopen("CONOUT$", "a", stdout);
310#endif
311
312 /* Set the default value for our display-system exponent, i.e., the
313 * product of the CRT exponent and the exponent corresponding to
314 * the frame-buffer's lookup table (LUT), if any. This is not an
315 * exhaustive list of LUT values (e.g., OpenStep has a lot of weird
316 * ones), but it should cover 99% of the current possibilities. And
317 * yes, these ifdefs are completely wasted in a Windows program... */
318
319#if defined(NeXT)
320 /* third-party utilities can modify the default LUT exponent */
321 LUT_exponent = 1.0 / 2.2;
322 /*
323 if (some_next_function_that_returns_gamma(&next_gamma))
324 LUT_exponent = 1.0 / next_gamma;
325 */
326#elif defined(sgi)
327 LUT_exponent = 1.0 / 1.7;
328 /* there doesn't seem to be any documented function to
329 * get the "gamma" value, so we do it the hard way */
330 infile = fopen("/etc/config/system.glGammaVal", "r");
331 if (infile) {
332 double sgi_gamma;
333
334 fgets(tmpline, 80, infile);
335 fclose(infile);
336 sgi_gamma = atof(tmpline);
337 if (sgi_gamma > 0.0)
338 LUT_exponent = 1.0 / sgi_gamma;
339 }
340#elif defined(Macintosh)
341 LUT_exponent = 1.8 / 2.61;
342 /*
343 if (some_mac_function_that_returns_gamma(&mac_gamma))
344 LUT_exponent = mac_gamma / 2.61;
345 */
346#else
347 LUT_exponent = 1.0; /* assume no LUT: most PCs */
348#endif
349
350 /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */
351 default_display_exponent = LUT_exponent * CRT_exponent;
352
353
354 /* If the user has set the SCREEN_GAMMA environment variable as suggested
355 * (somewhat imprecisely) in the libpng documentation, use that; otherwise
356 * use the default value we just calculated. Either way, the user may
357 * override this via a command-line option. */
358
359 if ((p = getenv("SCREEN_GAMMA")) != NULL)
360 rpng2_info.display_exponent = atof(p);
361 else
362 rpng2_info.display_exponent = default_display_exponent;
363
364
365 /* Windows really hates command lines, so we have to set up our own argv.
366 * Note that we do NOT bother with quoted arguments here, so don't use
367 * filenames with spaces in 'em! */
368
369 argv[argc++] = PROGNAME;
370 p = cmd;
371 for (;;) {
372 if (*p == ' ')
373 while (*++p == ' ')
374 ;
375 /* now p points at the first non-space after some spaces */
376 if (*p == '\0')
377 break; /* nothing after the spaces: done */
378 argv[argc++] = q = p;
379 while (*q && *q != ' ')
380 ++q;
381 /* now q points at a space or the end of the string */
382 if (*q == '\0')
383 break; /* last argv already terminated; quit */
384 *q = '\0'; /* change space to terminator */
385 p = q + 1;
386 }
387 argv[argc] = NULL; /* terminate the argv array itself */
388
389
390 /* Now parse the command line for options and the PNG filename. */
391
392 while (*++argv && !error) {
393 if (!strncmp(*argv, "-gamma", 2)) {
394 if (!*++argv)
395 ++error;
396 else {
397 rpng2_info.display_exponent = atof(*argv);
398 if (rpng2_info.display_exponent <= 0.0)
399 ++error;
400 }
401 } else if (!strncmp(*argv, "-bgcolor", 4)) {
402 if (!*++argv)
403 ++error;
404 else {
405 bgstr = *argv;
406 if (strlen(bgstr) != 7 || bgstr[0] != '#')
407 ++error;
408 else {
409 have_bg = TRUE;
410 bg_image = FALSE;
411 }
412 }
413 } else if (!strncmp(*argv, "-bgpat", 4)) {
414 if (!*++argv)
415 ++error;
416 else {
417 pat = atoi(*argv) - 1;
418 if (pat < 0 || pat >= num_bgpat)
419 ++error;
420 else {
421 bg_image = TRUE;
422 have_bg = FALSE;
423 }
424 }
425 } else if (!strncmp(*argv, "-timing", 2)) {
426 timing = TRUE;
427 } else {
428 if (**argv != '-') {
429 filename = *argv;
430 if (argv[1]) /* shouldn't be any more args after filename */
431 ++error;
432 } else
433 ++error; /* not expecting any other options */
434 }
435 }
436
437 if (!filename)
438 ++error;
439
440
441 /* print usage screen if any errors up to this point */
442
443 if (error) {
444#ifndef __CYGWIN__
445 int ch;
446#endif
447
448 fprintf(stderr, "\n%s %s: %s\n\n", PROGNAME, VERSION, appname);
449 readpng2_version_info();
450 fprintf(stderr, "\n"
451 "Usage: %s [-gamma exp] [-bgcolor bg | -bgpat pat] [-timing]\n"
452 " %*s file.png\n\n"
453 " exp \ttransfer-function exponent (``gamma'') of the display\n"
454 "\t\t system in floating-point format (e.g., ``%.1f''); equal\n"
455 "\t\t to the product of the lookup-table exponent (varies)\n"
456 "\t\t and the CRT exponent (usually 2.2); must be positive\n"
457 " bg \tdesired background color in 7-character hex RGB format\n"
458 "\t\t (e.g., ``#ff7700'' for orange: same as HTML colors);\n"
459 "\t\t used with transparent images; overrides -bgpat option\n"
460 " pat \tdesired background pattern number (1-%d); used with\n"
461 "\t\t transparent images; overrides -bgcolor option\n"
462 " -timing\tenables delay for every block read, to simulate modem\n"
463 "\t\t download of image (~36 Kbps)\n"
464 "\nPress Q, Esc or mouse button 1 after image is displayed to quit.\n"
465#ifndef __CYGWIN__
466 "Press Q or Esc to quit this usage screen. ",
467#else
468 ,
469#endif
470 PROGNAME,
471#if (defined(__i386__) || defined(_M_IX86) || defined(__x86_64__)) && \
472 !(defined(__CYGWIN__) || defined(__MINGW32__))
473 (int)strlen(PROGNAME), " ",
474#endif
475 (int)strlen(PROGNAME), " ", default_display_exponent, num_bgpat);
476 fflush(stderr);
477#ifndef __CYGWIN__
478 do
479 ch = _getch();
480 while (ch != 'q' && ch != 'Q' && ch != 0x1B);
481#endif
482 exit(1);
483 }
484
485
486 if (!(infile = fopen(filename, "rb"))) {
487 fprintf(stderr, PROGNAME ": can't open PNG file [%s]\n", filename);
488 ++error;
489 } else {
490 incount = fread(inbuf, 1, INBUFSIZE, infile);
491 if (incount < 8 || !readpng2_check_sig(inbuf, 8)) {
492 fprintf(stderr, PROGNAME
493 ": [%s] is not a PNG file: incorrect signature\n",
494 filename);
495 ++error;
496 } else if ((rc = readpng2_init(&rpng2_info)) != 0) {
497 switch (rc) {
498 case 2:
499 fprintf(stderr, PROGNAME
500 ": [%s] has bad IHDR (libpng longjmp)\n", filename);
501 break;
502 case 4:
503 fprintf(stderr, PROGNAME ": insufficient memory\n");
504 break;
505 default:
506 fprintf(stderr, PROGNAME
507 ": unknown readpng2_init() error\n");
508 break;
509 }
510 ++error;
511 }
512 if (error)
513 fclose(infile);
514 }
515
516
517 if (error) {
518#ifndef __CYGWIN__
519 int ch;
520#endif
521
522 fprintf(stderr, PROGNAME ": aborting.\n");
523#ifndef __CYGWIN__
524 do
525 ch = _getch();
526 while (ch != 'q' && ch != 'Q' && ch != 0x1B);
527#endif
528 exit(2);
529 } else {
530 fprintf(stderr, "\n%s %s: %s\n", PROGNAME, VERSION, appname);
531#ifndef __CYGWIN__
532 fprintf(stderr,
533 "\n [console window: closing this window will terminate %s]\n\n",
534 PROGNAME);
535#endif
536 fflush(stderr);
537 }
538
539
540 /* set the title-bar string, but make sure buffer doesn't overflow */
541
542 alen = strlen(appname);
543 flen = strlen(filename);
544 if (alen + flen + 3 > 1023)
545 sprintf(titlebar, "%s: ...%s", appname, filename+(alen+flen+6-1023));
546 else
547 sprintf(titlebar, "%s: %s", appname, filename);
548
549
550 /* set some final rpng2_info variables before entering main data loop */
551
552 if (have_bg) {
553 unsigned r, g, b; /* this approach quiets compiler warnings */
554
555 sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);
556 rpng2_info.bg_red = (uch)r;
557 rpng2_info.bg_green = (uch)g;
558 rpng2_info.bg_blue = (uch)b;
559 } else
560 rpng2_info.need_bgcolor = TRUE;
561
562 rpng2_info.state = kPreInit;
563 rpng2_info.mainprog_init = rpng2_win_init;
564 rpng2_info.mainprog_display_row = rpng2_win_display_row;
565 rpng2_info.mainprog_finish_display = rpng2_win_finish_display;
566
567
568 /* OK, this is the fun part: call readpng2_decode_data() at the start of
569 * the loop to deal with our first buffer of data (read in above to verify
570 * that the file is a PNG image), then loop through the file and continue
571 * calling the same routine to handle each chunk of data. It in turn
572 * passes the data to libpng, which will invoke one or more of our call-
573 * backs as decoded data become available. We optionally call Sleep() for
574 * one second per iteration to simulate downloading the image via an analog
575 * modem. */
576
577 for (;;) {
578 Trace((stderr, "about to call readpng2_decode_data()\n"))
579 if (readpng2_decode_data(&rpng2_info, inbuf, incount))
580 ++error;
581 Trace((stderr, "done with readpng2_decode_data()\n"))
582
583 if (error || incount != INBUFSIZE || rpng2_info.state == kDone) {
584 if (rpng2_info.state == kDone) {
585 Trace((stderr, "done decoding PNG image\n"))
586 } else if (ferror(infile)) {
587 fprintf(stderr, PROGNAME
588 ": error while reading PNG image file\n");
589 exit(3);
590 } else if (feof(infile)) {
591 fprintf(stderr, PROGNAME ": end of file reached "
592 "(unexpectedly) while reading PNG image file\n");
593 exit(3);
594 } else /* if (error) */ {
595 /* will print error message below */
596 }
597 break;
598 }
599
600 if (timing)
601 Sleep(1000L);
602
603 incount = fread(inbuf, 1, INBUFSIZE, infile);
604 }
605
606
607 /* clean up PNG stuff and report any decoding errors */
608
609 fclose(infile);
610 Trace((stderr, "about to call readpng2_cleanup()\n"))
611 readpng2_cleanup(&rpng2_info);
612
613 if (error) {
614 fprintf(stderr, PROGNAME ": libpng error while decoding PNG image\n");
615 exit(3);
616 }
617
618
619 /* wait for the user to tell us when to quit */
620
621 while (GetMessage(&msg, NULL, 0, 0)) {
622 TranslateMessage(&msg);
623 DispatchMessage(&msg);
624 }
625
626
627 /* we're done: clean up all image and Windows resources and go away */
628
629 Trace((stderr, "about to call rpng2_win_cleanup()\n"))
630 rpng2_win_cleanup();
631
632 return msg.wParam;
633}
634
635
636
637
638
639/* this function is called by readpng2_info_callback() in readpng2.c, which
640 * in turn is called by libpng after all of the pre-IDAT chunks have been
641 * read and processed--i.e., we now have enough info to finish initializing */
642
643static void rpng2_win_init()
644{
645 ulg i;
646 ulg rowbytes = rpng2_info.rowbytes;
647
648 Trace((stderr, "beginning rpng2_win_init()\n"))
649 Trace((stderr, " rowbytes = %d\n", rpng2_info.rowbytes))
650 Trace((stderr, " width = %ld\n", rpng2_info.width))
651 Trace((stderr, " height = %ld\n", rpng2_info.height))
652
653 rpng2_info.image_data = (uch *)malloc(rowbytes * rpng2_info.height);
654 if (!rpng2_info.image_data) {
655 readpng2_cleanup(&rpng2_info);
656 return;
657 }
658
659 rpng2_info.row_pointers = (uch **)malloc(rpng2_info.height * sizeof(uch *));
660 if (!rpng2_info.row_pointers) {
661 free(rpng2_info.image_data);
662 rpng2_info.image_data = NULL;
663 readpng2_cleanup(&rpng2_info);
664 return;
665 }
666
667 for (i = 0; i < rpng2_info.height; ++i)
668 rpng2_info.row_pointers[i] = rpng2_info.image_data + i*rowbytes;
669
670/*---------------------------------------------------------------------------
671 Do the basic Windows initialization stuff, make the window, and fill it
672 with the user-specified, file-specified or default background color.
673 ---------------------------------------------------------------------------*/
674
675 if (rpng2_win_create_window()) {
676 readpng2_cleanup(&rpng2_info);
677 return;
678 }
679
680 rpng2_info.state = kWindowInit;
681}
682
683
684
685
686
687static int rpng2_win_create_window()
688{
689 uch bg_red = rpng2_info.bg_red;
690 uch bg_green = rpng2_info.bg_green;
691 uch bg_blue = rpng2_info.bg_blue;
692 uch *dest;
693 int extra_width, extra_height;
694 ulg i, j;
695 WNDCLASSEX wndclass;
696 RECT rect;
697
698
699/*---------------------------------------------------------------------------
700 Allocate memory for the display-specific version of the image (round up
701 to multiple of 4 for Windows DIB).
702 ---------------------------------------------------------------------------*/
703
704 wimage_rowbytes = ((3*rpng2_info.width + 3L) >> 2) << 2;
705
706 if (!(dib = (uch *)malloc(sizeof(BITMAPINFOHEADER) +
707 wimage_rowbytes*rpng2_info.height)))
708 {
709 return 4; /* fail */
710 }
711
712/*---------------------------------------------------------------------------
713 Initialize the DIB. Negative height means to use top-down BMP ordering
714 (must be uncompressed, but that's what we want). Bit count of 1, 4 or 8
715 implies a colormap of RGBX quads, but 24-bit BMPs just use B,G,R values
716 directly => wimage_data begins immediately after BMP header.
717 ---------------------------------------------------------------------------*/
718
719 memset(dib, 0, sizeof(BITMAPINFOHEADER));
720 bmih = (BITMAPINFOHEADER *)dib;
721 bmih->biSize = sizeof(BITMAPINFOHEADER);
722 bmih->biWidth = rpng2_info.width;
723 bmih->biHeight = -((long)rpng2_info.height);
724 bmih->biPlanes = 1;
725 bmih->biBitCount = 24;
726 bmih->biCompression = 0;
727 wimage_data = dib + sizeof(BITMAPINFOHEADER);
728
729/*---------------------------------------------------------------------------
730 Fill window with the specified background color (default is black), but
731 defer loading faked "background image" until window is displayed (may be
732 slow to compute). Data are in BGR order.
733 ---------------------------------------------------------------------------*/
734
735 if (bg_image) { /* just fill with black for now */
736 memset(wimage_data, 0, wimage_rowbytes*rpng2_info.height);
737 } else {
738 for (j = 0; j < rpng2_info.height; ++j) {
739 dest = wimage_data + j*wimage_rowbytes;
740 for (i = rpng2_info.width; i > 0; --i) {
741 *dest++ = bg_blue;
742 *dest++ = bg_green;
743 *dest++ = bg_red;
744 }
745 }
746 }
747
748/*---------------------------------------------------------------------------
749 Set the window parameters.
750 ---------------------------------------------------------------------------*/
751
752 memset(&wndclass, 0, sizeof(wndclass));
753
754 wndclass.cbSize = sizeof(wndclass);
755 wndclass.style = CS_HREDRAW | CS_VREDRAW;
756 wndclass.lpfnWndProc = rpng2_win_wndproc;
757 wndclass.hInstance = global_hInst;
758 wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
759 wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
760 wndclass.hbrBackground = (HBRUSH)GetStockObject(DKGRAY_BRUSH);
761 wndclass.lpszMenuName = NULL;
762 wndclass.lpszClassName = progname;
763 wndclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
764
765 RegisterClassEx(&wndclass);
766
767/*---------------------------------------------------------------------------
768 Finally, create the window.
769 ---------------------------------------------------------------------------*/
770
771 extra_width = 2*(GetSystemMetrics(SM_CXBORDER) +
772 GetSystemMetrics(SM_CXDLGFRAME));
773 extra_height = 2*(GetSystemMetrics(SM_CYBORDER) +
774 GetSystemMetrics(SM_CYDLGFRAME)) +
775 GetSystemMetrics(SM_CYCAPTION);
776
777 global_hwnd = CreateWindow(progname, titlebar, WS_OVERLAPPEDWINDOW,
778 CW_USEDEFAULT, CW_USEDEFAULT, rpng2_info.width+extra_width,
779 rpng2_info.height+extra_height, NULL, NULL, global_hInst, NULL);
780
781 ShowWindow(global_hwnd, global_showmode);
782 UpdateWindow(global_hwnd);
783
784/*---------------------------------------------------------------------------
785 Now compute the background image and display it. If it fails (memory
786 allocation), revert to a plain background color.
787 ---------------------------------------------------------------------------*/
788
789 if (bg_image) {
790 static const char *msg = "Computing background image...";
791 int x, y, len = strlen(msg);
792 HDC hdc = GetDC(global_hwnd);
793 TEXTMETRIC tm;
794
795 GetTextMetrics(hdc, &tm);
796 x = (rpng2_info.width - len*tm.tmAveCharWidth)/2;
797 y = (rpng2_info.height - tm.tmHeight)/2;
798 SetBkMode(hdc, TRANSPARENT);
799 SetTextColor(hdc, GetSysColor(COLOR_HIGHLIGHTTEXT));
800 /* this can still begin out of bounds even if x is positive (???): */
801 TextOut(hdc, ((x < 0)? 0 : x), ((y < 0)? 0 : y), msg, len);
802 ReleaseDC(global_hwnd, hdc);
803
804 rpng2_win_load_bg_image(); /* resets bg_image if fails */
805 }
806
807 if (!bg_image) {
808 for (j = 0; j < rpng2_info.height; ++j) {
809 dest = wimage_data + j*wimage_rowbytes;
810 for (i = rpng2_info.width; i > 0; --i) {
811 *dest++ = bg_blue;
812 *dest++ = bg_green;
813 *dest++ = bg_red;
814 }
815 }
816 }
817
818 rect.left = 0L;
819 rect.top = 0L;
820 rect.right = (LONG)rpng2_info.width; /* possibly off by one? */
821 rect.bottom = (LONG)rpng2_info.height; /* possibly off by one? */
822 InvalidateRect(global_hwnd, &rect, FALSE);
823 UpdateWindow(global_hwnd); /* similar to XFlush() */
824
825 return 0;
826
827} /* end function rpng2_win_create_window() */
828
829
830
831
832
833static int rpng2_win_load_bg_image()
834{
835 uch *src, *dest;
836 uch r1, r2, g1, g2, b1, b2;
837 uch r1_inv, r2_inv, g1_inv, g2_inv, b1_inv, b2_inv;
838 int k, hmax, max;
839 int xidx, yidx, yidx_max = (bgscale-1);
840 int even_odd_vert, even_odd_horiz, even_odd;
841 int invert_gradient2 = (bg[pat].type & 0x08);
842 int invert_column;
843 ulg i, row;
844
845/*---------------------------------------------------------------------------
846 Allocate buffer for fake background image to be used with transparent
847 images; if this fails, revert to plain background color.
848 ---------------------------------------------------------------------------*/
849
850 bg_rowbytes = 3 * rpng2_info.width;
851 bg_data = (uch *)malloc(bg_rowbytes * rpng2_info.height);
852 if (!bg_data) {
853 fprintf(stderr, PROGNAME
854 ": unable to allocate memory for background image\n");
855 bg_image = 0;
856 return 1;
857 }
858
859/*---------------------------------------------------------------------------
860 Vertical gradients (ramps) in NxN squares, alternating direction and
861 colors (N == bgscale).
862 ---------------------------------------------------------------------------*/
863
864 if ((bg[pat].type & 0x07) == 0) {
865 uch r1_min = rgb[bg[pat].rgb1_min].r;
866 uch g1_min = rgb[bg[pat].rgb1_min].g;
867 uch b1_min = rgb[bg[pat].rgb1_min].b;
868 uch r2_min = rgb[bg[pat].rgb2_min].r;
869 uch g2_min = rgb[bg[pat].rgb2_min].g;
870 uch b2_min = rgb[bg[pat].rgb2_min].b;
871 int r1_diff = rgb[bg[pat].rgb1_max].r - r1_min;
872 int g1_diff = rgb[bg[pat].rgb1_max].g - g1_min;
873 int b1_diff = rgb[bg[pat].rgb1_max].b - b1_min;
874 int r2_diff = rgb[bg[pat].rgb2_max].r - r2_min;
875 int g2_diff = rgb[bg[pat].rgb2_max].g - g2_min;
876 int b2_diff = rgb[bg[pat].rgb2_max].b - b2_min;
877
878 for (row = 0; row < rpng2_info.height; ++row) {
879 yidx = row % bgscale;
880 even_odd_vert = (row / bgscale) & 1;
881
882 r1 = r1_min + (r1_diff * yidx) / yidx_max;
883 g1 = g1_min + (g1_diff * yidx) / yidx_max;
884 b1 = b1_min + (b1_diff * yidx) / yidx_max;
885 r1_inv = r1_min + (r1_diff * (yidx_max-yidx)) / yidx_max;
886 g1_inv = g1_min + (g1_diff * (yidx_max-yidx)) / yidx_max;
887 b1_inv = b1_min + (b1_diff * (yidx_max-yidx)) / yidx_max;
888
889 r2 = r2_min + (r2_diff * yidx) / yidx_max;
890 g2 = g2_min + (g2_diff * yidx) / yidx_max;
891 b2 = b2_min + (b2_diff * yidx) / yidx_max;
892 r2_inv = r2_min + (r2_diff * (yidx_max-yidx)) / yidx_max;
893 g2_inv = g2_min + (g2_diff * (yidx_max-yidx)) / yidx_max;
894 b2_inv = b2_min + (b2_diff * (yidx_max-yidx)) / yidx_max;
895
896 dest = bg_data + row*bg_rowbytes;
897 for (i = 0; i < rpng2_info.width; ++i) {
898 even_odd_horiz = (i / bgscale) & 1;
899 even_odd = even_odd_vert ^ even_odd_horiz;
900 invert_column =
901 (even_odd_horiz && (bg[pat].type & 0x10));
902 if (even_odd == 0) { /* gradient #1 */
903 if (invert_column) {
904 *dest++ = r1_inv;
905 *dest++ = g1_inv;
906 *dest++ = b1_inv;
907 } else {
908 *dest++ = r1;
909 *dest++ = g1;
910 *dest++ = b1;
911 }
912 } else { /* gradient #2 */
913 if ((invert_column && invert_gradient2) ||
914 (!invert_column && !invert_gradient2))
915 {
916 *dest++ = r2; /* not inverted or */
917 *dest++ = g2; /* doubly inverted */
918 *dest++ = b2;
919 } else {
920 *dest++ = r2_inv;
921 *dest++ = g2_inv; /* singly inverted */
922 *dest++ = b2_inv;
923 }
924 }
925 }
926 }
927
928/*---------------------------------------------------------------------------
929 Soft gradient-diamonds with scale = bgscale. Code contributed by Adam
930 M. Costello.
931 ---------------------------------------------------------------------------*/
932
933 } else if ((bg[pat].type & 0x07) == 1) {
934
935 hmax = (bgscale-1)/2; /* half the max weight of a color */
936 max = 2*hmax; /* the max weight of a color */
937
938 r1 = rgb[bg[pat].rgb1_max].r;
939 g1 = rgb[bg[pat].rgb1_max].g;
940 b1 = rgb[bg[pat].rgb1_max].b;
941 r2 = rgb[bg[pat].rgb2_max].r;
942 g2 = rgb[bg[pat].rgb2_max].g;
943 b2 = rgb[bg[pat].rgb2_max].b;
944
945 for (row = 0; row < rpng2_info.height; ++row) {
946 yidx = row % bgscale;
947 if (yidx > hmax)
948 yidx = bgscale-1 - yidx;
949 dest = bg_data + row*bg_rowbytes;
950 for (i = 0; i < rpng2_info.width; ++i) {
951 xidx = i % bgscale;
952 if (xidx > hmax)
953 xidx = bgscale-1 - xidx;
954 k = xidx + yidx;
955 *dest++ = (k*r1 + (max-k)*r2) / max;
956 *dest++ = (k*g1 + (max-k)*g2) / max;
957 *dest++ = (k*b1 + (max-k)*b2) / max;
958 }
959 }
960
961/*---------------------------------------------------------------------------
962 Radial "starburst" with azimuthal sinusoids; [eventually number of sinu-
963 soids will equal bgscale?]. This one is slow but very cool. Code con-
964 tributed by Pieter S. van der Meulen (originally in Smalltalk).
965 ---------------------------------------------------------------------------*/
966
967 } else if ((bg[pat].type & 0x07) == 2) {
968 uch ch;
969 int ii, x, y, hw, hh, grayspot;
970 double freq, rotate, saturate, gray, intensity;
971 double angle=0.0, aoffset=0.0, maxDist, dist;
972 double red=0.0, green=0.0, blue=0.0, hue, s, v, f, p, q, t;
973
974 fprintf(stderr, "%s: computing radial background...",
975 PROGNAME);
976 fflush(stderr);
977
978 hh = rpng2_info.height / 2;
979 hw = rpng2_info.width / 2;
980
981 /* variables for radial waves:
982 * aoffset: number of degrees to rotate hue [CURRENTLY NOT USED]
983 * freq: number of color beams originating from the center
984 * grayspot: size of the graying center area (anti-alias)
985 * rotate: rotation of the beams as a function of radius
986 * saturate: saturation of beams' shape azimuthally
987 */
988 angle = CLIP(angle, 0.0, 360.0);
989 grayspot = CLIP(bg[pat].bg_gray, 1, (hh + hw));
990 freq = MAX((double)bg[pat].bg_freq, 0.0);
991 saturate = (double)bg[pat].bg_bsat * 0.1;
992 rotate = (double)bg[pat].bg_brot * 0.1;
993 gray = 0.0;
994 intensity = 0.0;
995 maxDist = (double)((hw*hw) + (hh*hh));
996
997 for (row = 0; row < rpng2_info.height; ++row) {
998 y = row - hh;
999 dest = bg_data + row*bg_rowbytes;
1000 for (i = 0; i < rpng2_info.width; ++i) {
1001 x = i - hw;
1002 angle = (x == 0)? PI_2 : atan((double)y / (double)x);
1003 gray = (double)MAX(ABS(y), ABS(x)) / grayspot;
1004 gray = MIN(1.0, gray);
1005 dist = (double)((x*x) + (y*y)) / maxDist;
1006 intensity = cos((angle+(rotate*dist*PI)) * freq) *
1007 gray * saturate;
1008 intensity = (MAX(MIN(intensity,1.0),-1.0) + 1.0) * 0.5;
1009 hue = (angle + PI) * INV_PI_360 + aoffset;
1010 s = gray * ((double)(ABS(x)+ABS(y)) / (double)(hw + hh));
1011 s = MIN(MAX(s,0.0), 1.0);
1012 v = MIN(MAX(intensity,0.0), 1.0);
1013
1014 if (s == 0.0) {
1015 ch = (uch)(v * 255.0);
1016 *dest++ = ch;
1017 *dest++ = ch;
1018 *dest++ = ch;
1019 } else {
1020 if ((hue < 0.0) || (hue >= 360.0))
1021 hue -= (((int)(hue / 360.0)) * 360.0);
1022 hue /= 60.0;
1023 ii = (int)hue;
1024 f = hue - (double)ii;
1025 p = (1.0 - s) * v;
1026 q = (1.0 - (s * f)) * v;
1027 t = (1.0 - (s * (1.0 - f))) * v;
1028 if (ii == 0) { red = v; green = t; blue = p; }
1029 else if (ii == 1) { red = q; green = v; blue = p; }
1030 else if (ii == 2) { red = p; green = v; blue = t; }
1031 else if (ii == 3) { red = p; green = q; blue = v; }
1032 else if (ii == 4) { red = t; green = p; blue = v; }
1033 else if (ii == 5) { red = v; green = p; blue = q; }
1034 *dest++ = (uch)(red * 255.0);
1035 *dest++ = (uch)(green * 255.0);
1036 *dest++ = (uch)(blue * 255.0);
1037 }
1038 }
1039 }
1040 fprintf(stderr, "done.\n");
1041 fflush(stderr);
1042 }
1043
1044/*---------------------------------------------------------------------------
1045 Blast background image to display buffer before beginning PNG decode;
1046 calling function will handle invalidation and UpdateWindow() call.
1047 ---------------------------------------------------------------------------*/
1048
1049 for (row = 0; row < rpng2_info.height; ++row) {
1050 src = bg_data + row*bg_rowbytes;
1051 dest = wimage_data + row*wimage_rowbytes;
1052 for (i = rpng2_info.width; i > 0; --i) {
1053 r1 = *src++;
1054 g1 = *src++;
1055 b1 = *src++;
1056 *dest++ = b1;
1057 *dest++ = g1; /* note reverse order */
1058 *dest++ = r1;
1059 }
1060 }
1061
1062 return 0;
1063
1064} /* end function rpng2_win_load_bg_image() */
1065
1066
1067
1068
1069
1070static void rpng2_win_display_row(ulg row)
1071{
1072 uch bg_red = rpng2_info.bg_red;
1073 uch bg_green = rpng2_info.bg_green;
1074 uch bg_blue = rpng2_info.bg_blue;
1075 uch *src, *src2=NULL, *dest;
1076 uch r, g, b, a;
1077 ulg i;
1078 static int rows=0;
1079 static ulg firstrow;
1080
1081/*---------------------------------------------------------------------------
1082 rows and firstrow simply track how many rows (and which ones) have not
1083 yet been displayed; alternatively, we could call InvalidateRect() for
1084 every row and not bother with the records-keeping.
1085 ---------------------------------------------------------------------------*/
1086
1087 Trace((stderr, "beginning rpng2_win_display_row()\n"))
1088
1089 if (rows == 0)
1090 firstrow = row; /* first row not yet displayed */
1091
1092 ++rows; /* count of rows received but not yet displayed */
1093
1094/*---------------------------------------------------------------------------
1095 Aside from the use of the rpng2_info struct and the lack of an outer
1096 loop (over rows), this routine is identical to rpng_win_display_image()
1097 in the non-progressive version of the program.
1098 ---------------------------------------------------------------------------*/
1099
1100 src = rpng2_info.image_data + row*rpng2_info.rowbytes;
1101 if (bg_image)
1102 src2 = bg_data + row*bg_rowbytes;
1103 dest = wimage_data + row*wimage_rowbytes;
1104
1105 if (rpng2_info.channels == 3) {
1106 for (i = rpng2_info.width; i > 0; --i) {
1107 r = *src++;
1108 g = *src++;
1109 b = *src++;
1110 *dest++ = b;
1111 *dest++ = g; /* note reverse order */
1112 *dest++ = r;
1113 }
1114 } else /* if (rpng2_info.channels == 4) */ {
1115 for (i = rpng2_info.width; i > 0; --i) {
1116 r = *src++;
1117 g = *src++;
1118 b = *src++;
1119 a = *src++;
1120 if (bg_image) {
1121 bg_red = *src2++;
1122 bg_green = *src2++;
1123 bg_blue = *src2++;
1124 }
1125 if (a == 255) {
1126 *dest++ = b;
1127 *dest++ = g;
1128 *dest++ = r;
1129 } else if (a == 0) {
1130 *dest++ = bg_blue;
1131 *dest++ = bg_green;
1132 *dest++ = bg_red;
1133 } else {
1134 /* this macro (copied from png.h) composites the
1135 * foreground and background values and puts the
1136 * result into the first argument; there are no
1137 * side effects with the first argument */
1138 alpha_composite(*dest++, b, a, bg_blue);
1139 alpha_composite(*dest++, g, a, bg_green);
1140 alpha_composite(*dest++, r, a, bg_red);
1141 }
1142 }
1143 }
1144
1145/*---------------------------------------------------------------------------
1146 Display after every 16 rows or when on last row. (Region may include
1147 previously displayed lines due to interlacing--i.e., not contiguous.)
1148 ---------------------------------------------------------------------------*/
1149
1150 if ((rows & 0xf) == 0 || row == rpng2_info.height-1) {
1151 RECT rect;
1152
1153 rect.left = 0L;
1154 rect.top = (LONG)firstrow;
1155 rect.right = (LONG)rpng2_info.width; /* possibly off by one? */
1156 rect.bottom = (LONG)row + 1L; /* possibly off by one? */
1157 InvalidateRect(global_hwnd, &rect, FALSE);
1158 UpdateWindow(global_hwnd); /* similar to XFlush() */
1159 rows = 0;
1160 }
1161
1162} /* end function rpng2_win_display_row() */
1163
1164
1165
1166
1167
1168static void rpng2_win_finish_display()
1169{
1170 Trace((stderr, "beginning rpng2_win_finish_display()\n"))
1171
1172 /* last row has already been displayed by rpng2_win_display_row(), so
1173 * we have nothing to do here except set a flag and let the user know
1174 * that the image is done */
1175
1176 rpng2_info.state = kDone;
1177 printf(
1178#ifndef __CYGWIN__
1179 "Done. Press Q, Esc or mouse button 1 (within image window) to quit.\n"
1180#else
1181 "Done. Press mouse button 1 (within image window) to quit.\n"
1182#endif
1183 );
1184 fflush(stdout);
1185}
1186
1187
1188
1189
1190
1191static void rpng2_win_cleanup()
1192{
1193 if (bg_image && bg_data) {
1194 free(bg_data);
1195 bg_data = NULL;
1196 }
1197
1198 if (rpng2_info.image_data) {
1199 free(rpng2_info.image_data);
1200 rpng2_info.image_data = NULL;
1201 }
1202
1203 if (rpng2_info.row_pointers) {
1204 free(rpng2_info.row_pointers);
1205 rpng2_info.row_pointers = NULL;
1206 }
1207
1208 if (dib) {
1209 free(dib);
1210 dib = NULL;
1211 }
1212}
1213
1214
1215
1216
1217
1218LRESULT CALLBACK rpng2_win_wndproc(HWND hwnd, UINT iMsg, WPARAM wP, LPARAM lP)
1219{
1220 HDC hdc;
1221 PAINTSTRUCT ps;
1222 int rc;
1223
1224 switch (iMsg) {
1225 case WM_CREATE:
1226 /* one-time processing here, if any */
1227 return 0;
1228
1229 case WM_PAINT:
1230 hdc = BeginPaint(hwnd, &ps);
1231 rc = StretchDIBits(hdc, 0, 0, rpng2_info.width, rpng2_info.height,
1232 0, 0, rpng2_info.width, rpng2_info.height,
1233 wimage_data, (BITMAPINFO *)bmih,
1234 0, SRCCOPY);
1235 EndPaint(hwnd, &ps);
1236 return 0;
1237
1238 /* wait for the user to tell us when to quit */
1239 case WM_CHAR:
1240 switch (wP) { /* only need one, so ignore repeat count */
1241 case 'q':
1242 case 'Q':
1243 case 0x1B: /* Esc key */
1244 PostQuitMessage(0);
1245 }
1246 return 0;
1247
1248 case WM_LBUTTONDOWN: /* another way of quitting */
1249 case WM_DESTROY:
1250 PostQuitMessage(0);
1251 return 0;
1252 }
1253
1254 return DefWindowProc(hwnd, iMsg, wP, lP);
1255}