OLD | NEW |
(Empty) | |
| 1 /*--------------------------------------------------------------------------- |
| 2 |
| 3 rpng - simple PNG display program rpng-win.c |
| 4 |
| 5 This program decodes and displays PNG images, with gamma correction and |
| 6 optionally with a user-specified background color (in case the image has |
| 7 transparency). It is very nearly the most basic PNG viewer possible. |
| 8 This version is for 32-bit Windows; it may compile under 16-bit Windows |
| 9 with a little tweaking (or maybe not). |
| 10 |
| 11 to do: |
| 12 - handle quoted command-line args (especially filenames with spaces) |
| 13 - have minimum window width: oh well |
| 14 - use %.1023s to simplify truncation of title-bar string? |
| 15 |
| 16 --------------------------------------------------------------------------- |
| 17 |
| 18 Changelog: |
| 19 - 1.00: initial public release |
| 20 - 1.01: modified to allow abbreviated options; fixed long/ulong mis- |
| 21 match; switched to png_jmpbuf() macro |
| 22 - 1.02: added extra set of parentheses to png_jmpbuf() macro; fixed |
| 23 command-line parsing bug |
| 24 - 1.10: enabled "message window"/console (thanks to David Geldreich) |
| 25 - 2.00: dual-licensed (added GNU GPL) |
| 26 - 2.01: fixed improper display of usage screen on PNG error(s) |
| 27 |
| 28 --------------------------------------------------------------------------- |
| 29 |
| 30 Copyright (c) 1998-2008 Greg Roelofs. All rights reserved. |
| 31 |
| 32 This software is provided "as is," without warranty of any kind, |
| 33 express or implied. In no event shall the author or contributors |
| 34 be held liable for any damages arising in any way from the use of |
| 35 this software. |
| 36 |
| 37 The contents of this file are DUAL-LICENSED. You may modify and/or |
| 38 redistribute this software according to the terms of one of the |
| 39 following two licenses (at your option): |
| 40 |
| 41 |
| 42 LICENSE 1 ("BSD-like with advertising clause"): |
| 43 |
| 44 Permission is granted to anyone to use this software for any purpose, |
| 45 including commercial applications, and to alter it and redistribute |
| 46 it freely, subject to the following restrictions: |
| 47 |
| 48 1. Redistributions of source code must retain the above copyright |
| 49 notice, disclaimer, and this list of conditions. |
| 50 2. Redistributions in binary form must reproduce the above copyright |
| 51 notice, disclaimer, and this list of conditions in the documenta- |
| 52 tion and/or other materials provided with the distribution. |
| 53 3. All advertising materials mentioning features or use of this |
| 54 software must display the following acknowledgment: |
| 55 |
| 56 This product includes software developed by Greg Roelofs |
| 57 and contributors for the book, "PNG: The Definitive Guide," |
| 58 published by O'Reilly and Associates. |
| 59 |
| 60 |
| 61 LICENSE 2 (GNU GPL v2 or later): |
| 62 |
| 63 This program is free software; you can redistribute it and/or modify |
| 64 it under the terms of the GNU General Public License as published by |
| 65 the Free Software Foundation; either version 2 of the License, or |
| 66 (at your option) any later version. |
| 67 |
| 68 This program is distributed in the hope that it will be useful, |
| 69 but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 70 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 71 GNU General Public License for more details. |
| 72 |
| 73 You should have received a copy of the GNU General Public License |
| 74 along with this program; if not, write to the Free Software Foundation, |
| 75 Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 76 |
| 77 ---------------------------------------------------------------------------*/ |
| 78 |
| 79 #define PROGNAME "rpng-win" |
| 80 #define LONGNAME "Simple PNG Viewer for Windows" |
| 81 #define VERSION "2.01 of 16 March 2008" |
| 82 |
| 83 #include <stdio.h> |
| 84 #include <stdlib.h> |
| 85 #include <string.h> |
| 86 #include <time.h> |
| 87 #include <windows.h> |
| 88 #ifdef __CYGWIN__ |
| 89 /* getch replacement. Turns out, we don't really need this, |
| 90 * but leave it here if we ever enable any of the uses of |
| 91 * _getch in the main code |
| 92 */ |
| 93 #include <unistd.h> |
| 94 #include <termio.h> |
| 95 #include <sys/ioctl.h> |
| 96 int repl_getch( void ) |
| 97 { |
| 98 char ch; |
| 99 int fd = fileno(stdin); |
| 100 struct termio old_tty, new_tty; |
| 101 |
| 102 ioctl(fd, TCGETA, &old_tty); |
| 103 new_tty = old_tty; |
| 104 new_tty.c_lflag &= ~(ICANON | ECHO | ISIG); |
| 105 ioctl(fd, TCSETA, &new_tty); |
| 106 fread(&ch, 1, sizeof(ch), stdin); |
| 107 ioctl(fd, TCSETA, &old_tty); |
| 108 |
| 109 return ch; |
| 110 } |
| 111 #define _getch repl_getch |
| 112 #else |
| 113 #include <conio.h> /* only for _getch() */ |
| 114 #endif |
| 115 |
| 116 /* #define DEBUG : this enables the Trace() macros */ |
| 117 |
| 118 #include "readpng.h" /* typedefs, common macros, readpng prototypes */ |
| 119 |
| 120 |
| 121 /* could just include png.h, but this macro is the only thing we need |
| 122 * (name and typedefs changed to local versions); note that side effects |
| 123 * only happen with alpha (which could easily be avoided with |
| 124 * "ush acopy = (alpha);") */ |
| 125 |
| 126 #define alpha_composite(composite, fg, alpha, bg) { \ |
| 127 ush temp = ((ush)(fg)*(ush)(alpha) + \ |
| 128 (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128); \ |
| 129 (composite) = (uch)((temp + (temp >> 8)) >> 8); \ |
| 130 } |
| 131 |
| 132 |
| 133 /* local prototypes */ |
| 134 static int rpng_win_create_window(HINSTANCE hInst, int showmode); |
| 135 static int rpng_win_display_image(void); |
| 136 static void rpng_win_cleanup(void); |
| 137 LRESULT CALLBACK rpng_win_wndproc(HWND, UINT, WPARAM, LPARAM); |
| 138 |
| 139 |
| 140 static char titlebar[1024]; |
| 141 static char *progname = PROGNAME; |
| 142 static char *appname = LONGNAME; |
| 143 static char *filename; |
| 144 static FILE *infile; |
| 145 |
| 146 static char *bgstr; |
| 147 static uch bg_red=0, bg_green=0, bg_blue=0; |
| 148 |
| 149 static double display_exponent; |
| 150 |
| 151 static ulg image_width, image_height, image_rowbytes; |
| 152 static int image_channels; |
| 153 static uch *image_data; |
| 154 |
| 155 /* Windows-specific variables */ |
| 156 static ulg wimage_rowbytes; |
| 157 static uch *dib; |
| 158 static uch *wimage_data; |
| 159 static BITMAPINFOHEADER *bmih; |
| 160 |
| 161 static HWND global_hwnd; |
| 162 |
| 163 |
| 164 |
| 165 |
| 166 int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode) |
| 167 { |
| 168 char *args[1024]; /* arbitrary limit, but should suffice */ |
| 169 char *p, *q, **argv = args; |
| 170 int argc = 0; |
| 171 int rc, alen, flen; |
| 172 int error = 0; |
| 173 int have_bg = FALSE; |
| 174 double LUT_exponent; /* just the lookup table */ |
| 175 double CRT_exponent = 2.2; /* just the monitor */ |
| 176 double default_display_exponent; /* whole display system */ |
| 177 MSG msg; |
| 178 |
| 179 |
| 180 filename = (char *)NULL; |
| 181 |
| 182 #ifndef __CYGWIN__ |
| 183 /* First reenable console output, which normally goes to the bit bucket |
| 184 * for windowed apps. Closing the console window will terminate the |
| 185 * app. Thanks to David.Geldreich@realviz.com for supplying the magical |
| 186 * incantation. */ |
| 187 |
| 188 AllocConsole(); |
| 189 freopen("CONOUT$", "a", stderr); |
| 190 freopen("CONOUT$", "a", stdout); |
| 191 #endif |
| 192 |
| 193 |
| 194 /* Next set the default value for our display-system exponent, i.e., |
| 195 * the product of the CRT exponent and the exponent corresponding to |
| 196 * the frame-buffer's lookup table (LUT), if any. This is not an |
| 197 * exhaustive list of LUT values (e.g., OpenStep has a lot of weird |
| 198 * ones), but it should cover 99% of the current possibilities. And |
| 199 * yes, these ifdefs are completely wasted in a Windows program... */ |
| 200 |
| 201 #if defined(NeXT) |
| 202 LUT_exponent = 1.0 / 2.2; |
| 203 /* |
| 204 if (some_next_function_that_returns_gamma(&next_gamma)) |
| 205 LUT_exponent = 1.0 / next_gamma; |
| 206 */ |
| 207 #elif defined(sgi) |
| 208 LUT_exponent = 1.0 / 1.7; |
| 209 /* there doesn't seem to be any documented function to get the |
| 210 * "gamma" value, so we do it the hard way */ |
| 211 infile = fopen("/etc/config/system.glGammaVal", "r"); |
| 212 if (infile) { |
| 213 double sgi_gamma; |
| 214 |
| 215 fgets(tmpline, 80, infile); |
| 216 fclose(infile); |
| 217 sgi_gamma = atof(tmpline); |
| 218 if (sgi_gamma > 0.0) |
| 219 LUT_exponent = 1.0 / sgi_gamma; |
| 220 } |
| 221 #elif defined(Macintosh) |
| 222 LUT_exponent = 1.8 / 2.61; |
| 223 /* |
| 224 if (some_mac_function_that_returns_gamma(&mac_gamma)) |
| 225 LUT_exponent = mac_gamma / 2.61; |
| 226 */ |
| 227 #else |
| 228 LUT_exponent = 1.0; /* assume no LUT: most PCs */ |
| 229 #endif |
| 230 |
| 231 /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */ |
| 232 default_display_exponent = LUT_exponent * CRT_exponent; |
| 233 |
| 234 |
| 235 /* If the user has set the SCREEN_GAMMA environment variable as suggested |
| 236 * (somewhat imprecisely) in the libpng documentation, use that; otherwise |
| 237 * use the default value we just calculated. Either way, the user may |
| 238 * override this via a command-line option. */ |
| 239 |
| 240 if ((p = getenv("SCREEN_GAMMA")) != NULL) |
| 241 display_exponent = atof(p); |
| 242 else |
| 243 display_exponent = default_display_exponent; |
| 244 |
| 245 |
| 246 /* Windows really hates command lines, so we have to set up our own argv. |
| 247 * Note that we do NOT bother with quoted arguments here, so don't use |
| 248 * filenames with spaces in 'em! */ |
| 249 |
| 250 argv[argc++] = PROGNAME; |
| 251 p = cmd; |
| 252 for (;;) { |
| 253 if (*p == ' ') |
| 254 while (*++p == ' ') |
| 255 ; |
| 256 /* now p points at the first non-space after some spaces */ |
| 257 if (*p == '\0') |
| 258 break; /* nothing after the spaces: done */ |
| 259 argv[argc++] = q = p; |
| 260 while (*q && *q != ' ') |
| 261 ++q; |
| 262 /* now q points at a space or the end of the string */ |
| 263 if (*q == '\0') |
| 264 break; /* last argv already terminated; quit */ |
| 265 *q = '\0'; /* change space to terminator */ |
| 266 p = q + 1; |
| 267 } |
| 268 argv[argc] = NULL; /* terminate the argv array itself */ |
| 269 |
| 270 |
| 271 /* Now parse the command line for options and the PNG filename. */ |
| 272 |
| 273 while (*++argv && !error) { |
| 274 if (!strncmp(*argv, "-gamma", 2)) { |
| 275 if (!*++argv) |
| 276 ++error; |
| 277 else { |
| 278 display_exponent = atof(*argv); |
| 279 if (display_exponent <= 0.0) |
| 280 ++error; |
| 281 } |
| 282 } else if (!strncmp(*argv, "-bgcolor", 2)) { |
| 283 if (!*++argv) |
| 284 ++error; |
| 285 else { |
| 286 bgstr = *argv; |
| 287 if (strlen(bgstr) != 7 || bgstr[0] != '#') |
| 288 ++error; |
| 289 else |
| 290 have_bg = TRUE; |
| 291 } |
| 292 } else { |
| 293 if (**argv != '-') { |
| 294 filename = *argv; |
| 295 if (argv[1]) /* shouldn't be any more args after filename */ |
| 296 ++error; |
| 297 } else |
| 298 ++error; /* not expecting any other options */ |
| 299 } |
| 300 } |
| 301 |
| 302 if (!filename) |
| 303 ++error; |
| 304 |
| 305 |
| 306 /* print usage screen if any errors up to this point */ |
| 307 |
| 308 if (error) { |
| 309 #ifndef __CYGWIN__ |
| 310 int ch; |
| 311 #endif |
| 312 |
| 313 fprintf(stderr, "\n%s %s: %s\n\n", PROGNAME, VERSION, appname); |
| 314 readpng_version_info(); |
| 315 fprintf(stderr, "\n" |
| 316 "Usage: %s [-gamma exp] [-bgcolor bg] file.png\n" |
| 317 " exp \ttransfer-function exponent (``gamma'') of the display\n" |
| 318 "\t\t system in floating-point format (e.g., ``%.1f''); equal\n" |
| 319 "\t\t to the product of the lookup-table exponent (varies)\n" |
| 320 "\t\t and the CRT exponent (usually 2.2); must be positive\n" |
| 321 " bg \tdesired background color in 7-character hex RGB format\n" |
| 322 "\t\t (e.g., ``#ff7700'' for orange: same as HTML colors);\n" |
| 323 "\t\t used with transparent images\n" |
| 324 "\nPress Q, Esc or mouse button 1 after image is displayed to quit.\n" |
| 325 #ifndef __CYGWIN__ |
| 326 "Press Q or Esc to quit this usage screen.\n" |
| 327 #endif |
| 328 "\n", PROGNAME, default_display_exponent); |
| 329 #ifndef __CYGWIN__ |
| 330 do |
| 331 ch = _getch(); |
| 332 while (ch != 'q' && ch != 'Q' && ch != 0x1B); |
| 333 #endif |
| 334 exit(1); |
| 335 } |
| 336 |
| 337 |
| 338 if (!(infile = fopen(filename, "rb"))) { |
| 339 fprintf(stderr, PROGNAME ": can't open PNG file [%s]\n", filename); |
| 340 ++error; |
| 341 } else { |
| 342 if ((rc = readpng_init(infile, &image_width, &image_height)) != 0) { |
| 343 switch (rc) { |
| 344 case 1: |
| 345 fprintf(stderr, PROGNAME |
| 346 ": [%s] is not a PNG file: incorrect signature\n", |
| 347 filename); |
| 348 break; |
| 349 case 2: |
| 350 fprintf(stderr, PROGNAME |
| 351 ": [%s] has bad IHDR (libpng longjmp)\n", filename); |
| 352 break; |
| 353 case 4: |
| 354 fprintf(stderr, PROGNAME ": insufficient memory\n"); |
| 355 break; |
| 356 default: |
| 357 fprintf(stderr, PROGNAME |
| 358 ": unknown readpng_init() error\n"); |
| 359 break; |
| 360 } |
| 361 ++error; |
| 362 } |
| 363 if (error) |
| 364 fclose(infile); |
| 365 } |
| 366 |
| 367 |
| 368 if (error) { |
| 369 #ifndef __CYGWIN__ |
| 370 int ch; |
| 371 #endif |
| 372 |
| 373 fprintf(stderr, PROGNAME ": aborting.\n"); |
| 374 #ifndef __CYGWIN__ |
| 375 do |
| 376 ch = _getch(); |
| 377 while (ch != 'q' && ch != 'Q' && ch != 0x1B); |
| 378 #endif |
| 379 exit(2); |
| 380 } else { |
| 381 fprintf(stderr, "\n%s %s: %s\n", PROGNAME, VERSION, appname); |
| 382 #ifndef __CYGWIN__ |
| 383 fprintf(stderr, |
| 384 "\n [console window: closing this window will terminate %s]\n\n", |
| 385 PROGNAME); |
| 386 #endif |
| 387 } |
| 388 |
| 389 |
| 390 /* set the title-bar string, but make sure buffer doesn't overflow */ |
| 391 |
| 392 alen = strlen(appname); |
| 393 flen = strlen(filename); |
| 394 if (alen + flen + 3 > 1023) |
| 395 sprintf(titlebar, "%s: ...%s", appname, filename+(alen+flen+6-1023)); |
| 396 else |
| 397 sprintf(titlebar, "%s: %s", appname, filename); |
| 398 |
| 399 |
| 400 /* if the user didn't specify a background color on the command line, |
| 401 * check for one in the PNG file--if not, the initialized values of 0 |
| 402 * (black) will be used */ |
| 403 |
| 404 if (have_bg) { |
| 405 unsigned r, g, b; /* this approach quiets compiler warnings */ |
| 406 |
| 407 sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b); |
| 408 bg_red = (uch)r; |
| 409 bg_green = (uch)g; |
| 410 bg_blue = (uch)b; |
| 411 } else if (readpng_get_bgcolor(&bg_red, &bg_green, &bg_blue) > 1) { |
| 412 readpng_cleanup(TRUE); |
| 413 fprintf(stderr, PROGNAME |
| 414 ": libpng error while checking for background color\n"); |
| 415 exit(2); |
| 416 } |
| 417 |
| 418 |
| 419 /* do the basic Windows initialization stuff, make the window and fill it |
| 420 * with the background color */ |
| 421 |
| 422 if (rpng_win_create_window(hInst, showmode)) |
| 423 exit(2); |
| 424 |
| 425 |
| 426 /* decode the image, all at once */ |
| 427 |
| 428 Trace((stderr, "calling readpng_get_image()\n")) |
| 429 image_data = readpng_get_image(display_exponent, &image_channels, |
| 430 &image_rowbytes); |
| 431 Trace((stderr, "done with readpng_get_image()\n")) |
| 432 |
| 433 |
| 434 /* done with PNG file, so clean up to minimize memory usage (but do NOT |
| 435 * nuke image_data!) */ |
| 436 |
| 437 readpng_cleanup(FALSE); |
| 438 fclose(infile); |
| 439 |
| 440 if (!image_data) { |
| 441 fprintf(stderr, PROGNAME ": unable to decode PNG image\n"); |
| 442 exit(3); |
| 443 } |
| 444 |
| 445 |
| 446 /* display image (composite with background if requested) */ |
| 447 |
| 448 Trace((stderr, "calling rpng_win_display_image()\n")) |
| 449 if (rpng_win_display_image()) { |
| 450 free(image_data); |
| 451 exit(4); |
| 452 } |
| 453 Trace((stderr, "done with rpng_win_display_image()\n")) |
| 454 |
| 455 |
| 456 /* wait for the user to tell us when to quit */ |
| 457 |
| 458 printf( |
| 459 #ifndef __CYGWIN__ |
| 460 "Done. Press Q, Esc or mouse button 1 (within image window) to quit.\n" |
| 461 #else |
| 462 "Done. Press mouse button 1 (within image window) to quit.\n" |
| 463 #endif |
| 464 ); |
| 465 fflush(stdout); |
| 466 |
| 467 while (GetMessage(&msg, NULL, 0, 0)) { |
| 468 TranslateMessage(&msg); |
| 469 DispatchMessage(&msg); |
| 470 } |
| 471 |
| 472 |
| 473 /* OK, we're done: clean up all image and Windows resources and go away */ |
| 474 |
| 475 rpng_win_cleanup(); |
| 476 |
| 477 return msg.wParam; |
| 478 } |
| 479 |
| 480 |
| 481 |
| 482 |
| 483 |
| 484 static int rpng_win_create_window(HINSTANCE hInst, int showmode) |
| 485 { |
| 486 uch *dest; |
| 487 int extra_width, extra_height; |
| 488 ulg i, j; |
| 489 WNDCLASSEX wndclass; |
| 490 |
| 491 |
| 492 /*--------------------------------------------------------------------------- |
| 493 Allocate memory for the display-specific version of the image (round up |
| 494 to multiple of 4 for Windows DIB). |
| 495 ---------------------------------------------------------------------------*/ |
| 496 |
| 497 wimage_rowbytes = ((3*image_width + 3L) >> 2) << 2; |
| 498 |
| 499 if (!(dib = (uch *)malloc(sizeof(BITMAPINFOHEADER) + |
| 500 wimage_rowbytes*image_height))) |
| 501 { |
| 502 return 4; /* fail */ |
| 503 } |
| 504 |
| 505 /*--------------------------------------------------------------------------- |
| 506 Initialize the DIB. Negative height means to use top-down BMP ordering |
| 507 (must be uncompressed, but that's what we want). Bit count of 1, 4 or 8 |
| 508 implies a colormap of RGBX quads, but 24-bit BMPs just use B,G,R values |
| 509 directly => wimage_data begins immediately after BMP header. |
| 510 ---------------------------------------------------------------------------*/ |
| 511 |
| 512 memset(dib, 0, sizeof(BITMAPINFOHEADER)); |
| 513 bmih = (BITMAPINFOHEADER *)dib; |
| 514 bmih->biSize = sizeof(BITMAPINFOHEADER); |
| 515 bmih->biWidth = image_width; |
| 516 bmih->biHeight = -((long)image_height); |
| 517 bmih->biPlanes = 1; |
| 518 bmih->biBitCount = 24; |
| 519 bmih->biCompression = 0; |
| 520 wimage_data = dib + sizeof(BITMAPINFOHEADER); |
| 521 |
| 522 /*--------------------------------------------------------------------------- |
| 523 Fill in background color (black by default); data are in BGR order. |
| 524 ---------------------------------------------------------------------------*/ |
| 525 |
| 526 for (j = 0; j < image_height; ++j) { |
| 527 dest = wimage_data + j*wimage_rowbytes; |
| 528 for (i = image_width; i > 0; --i) { |
| 529 *dest++ = bg_blue; |
| 530 *dest++ = bg_green; |
| 531 *dest++ = bg_red; |
| 532 } |
| 533 } |
| 534 |
| 535 /*--------------------------------------------------------------------------- |
| 536 Set the window parameters. |
| 537 ---------------------------------------------------------------------------*/ |
| 538 |
| 539 memset(&wndclass, 0, sizeof(wndclass)); |
| 540 |
| 541 wndclass.cbSize = sizeof(wndclass); |
| 542 wndclass.style = CS_HREDRAW | CS_VREDRAW; |
| 543 wndclass.lpfnWndProc = rpng_win_wndproc; |
| 544 wndclass.hInstance = hInst; |
| 545 wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION); |
| 546 wndclass.hCursor = LoadCursor(NULL, IDC_ARROW); |
| 547 wndclass.hbrBackground = (HBRUSH)GetStockObject(DKGRAY_BRUSH); |
| 548 wndclass.lpszMenuName = NULL; |
| 549 wndclass.lpszClassName = progname; |
| 550 wndclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION); |
| 551 |
| 552 RegisterClassEx(&wndclass); |
| 553 |
| 554 /*--------------------------------------------------------------------------- |
| 555 Finally, create the window. |
| 556 ---------------------------------------------------------------------------*/ |
| 557 |
| 558 extra_width = 2*(GetSystemMetrics(SM_CXBORDER) + |
| 559 GetSystemMetrics(SM_CXDLGFRAME)); |
| 560 extra_height = 2*(GetSystemMetrics(SM_CYBORDER) + |
| 561 GetSystemMetrics(SM_CYDLGFRAME)) + |
| 562 GetSystemMetrics(SM_CYCAPTION); |
| 563 |
| 564 global_hwnd = CreateWindow(progname, titlebar, WS_OVERLAPPEDWINDOW, |
| 565 CW_USEDEFAULT, CW_USEDEFAULT, image_width+extra_width, |
| 566 image_height+extra_height, NULL, NULL, hInst, NULL); |
| 567 |
| 568 ShowWindow(global_hwnd, showmode); |
| 569 UpdateWindow(global_hwnd); |
| 570 |
| 571 return 0; |
| 572 |
| 573 } /* end function rpng_win_create_window() */ |
| 574 |
| 575 |
| 576 |
| 577 |
| 578 |
| 579 static int rpng_win_display_image() |
| 580 { |
| 581 uch *src, *dest; |
| 582 uch r, g, b, a; |
| 583 ulg i, row, lastrow; |
| 584 RECT rect; |
| 585 |
| 586 |
| 587 Trace((stderr, "beginning display loop (image_channels == %d)\n", |
| 588 image_channels)) |
| 589 Trace((stderr, "(width = %ld, rowbytes = %ld, wimage_rowbytes = %d)\n", |
| 590 image_width, image_rowbytes, wimage_rowbytes)) |
| 591 |
| 592 |
| 593 /*--------------------------------------------------------------------------- |
| 594 Blast image data to buffer. This whole routine takes place before the |
| 595 message loop begins, so there's no real point in any pseudo-progressive |
| 596 display... |
| 597 ---------------------------------------------------------------------------*/ |
| 598 |
| 599 for (lastrow = row = 0; row < image_height; ++row) { |
| 600 src = image_data + row*image_rowbytes; |
| 601 dest = wimage_data + row*wimage_rowbytes; |
| 602 if (image_channels == 3) { |
| 603 for (i = image_width; i > 0; --i) { |
| 604 r = *src++; |
| 605 g = *src++; |
| 606 b = *src++; |
| 607 *dest++ = b; |
| 608 *dest++ = g; /* note reverse order */ |
| 609 *dest++ = r; |
| 610 } |
| 611 } else /* if (image_channels == 4) */ { |
| 612 for (i = image_width; i > 0; --i) { |
| 613 r = *src++; |
| 614 g = *src++; |
| 615 b = *src++; |
| 616 a = *src++; |
| 617 if (a == 255) { |
| 618 *dest++ = b; |
| 619 *dest++ = g; |
| 620 *dest++ = r; |
| 621 } else if (a == 0) { |
| 622 *dest++ = bg_blue; |
| 623 *dest++ = bg_green; |
| 624 *dest++ = bg_red; |
| 625 } else { |
| 626 /* this macro (copied from png.h) composites the |
| 627 * foreground and background values and puts the |
| 628 * result into the first argument; there are no |
| 629 * side effects with the first argument */ |
| 630 alpha_composite(*dest++, b, a, bg_blue); |
| 631 alpha_composite(*dest++, g, a, bg_green); |
| 632 alpha_composite(*dest++, r, a, bg_red); |
| 633 } |
| 634 } |
| 635 } |
| 636 /* display after every 16 lines */ |
| 637 if (((row+1) & 0xf) == 0) { |
| 638 rect.left = 0L; |
| 639 rect.top = (LONG)lastrow; |
| 640 rect.right = (LONG)image_width; /* possibly off by one? */ |
| 641 rect.bottom = (LONG)lastrow + 16L; /* possibly off by one? */ |
| 642 InvalidateRect(global_hwnd, &rect, FALSE); |
| 643 UpdateWindow(global_hwnd); /* similar to XFlush() */ |
| 644 lastrow = row + 1; |
| 645 } |
| 646 } |
| 647 |
| 648 Trace((stderr, "calling final image-flush routine\n")) |
| 649 if (lastrow < image_height) { |
| 650 rect.left = 0L; |
| 651 rect.top = (LONG)lastrow; |
| 652 rect.right = (LONG)image_width; /* possibly off by one? */ |
| 653 rect.bottom = (LONG)image_height; /* possibly off by one? */ |
| 654 InvalidateRect(global_hwnd, &rect, FALSE); |
| 655 UpdateWindow(global_hwnd); /* similar to XFlush() */ |
| 656 } |
| 657 |
| 658 /* |
| 659 last param determines whether or not background is wiped before paint |
| 660 InvalidateRect(global_hwnd, NULL, TRUE); |
| 661 UpdateWindow(global_hwnd); |
| 662 */ |
| 663 |
| 664 return 0; |
| 665 } |
| 666 |
| 667 |
| 668 |
| 669 |
| 670 |
| 671 static void rpng_win_cleanup() |
| 672 { |
| 673 if (image_data) { |
| 674 free(image_data); |
| 675 image_data = NULL; |
| 676 } |
| 677 |
| 678 if (dib) { |
| 679 free(dib); |
| 680 dib = NULL; |
| 681 } |
| 682 } |
| 683 |
| 684 |
| 685 |
| 686 |
| 687 |
| 688 LRESULT CALLBACK rpng_win_wndproc(HWND hwnd, UINT iMsg, WPARAM wP, LPARAM lP) |
| 689 { |
| 690 HDC hdc; |
| 691 PAINTSTRUCT ps; |
| 692 int rc; |
| 693 |
| 694 switch (iMsg) { |
| 695 case WM_CREATE: |
| 696 /* one-time processing here, if any */ |
| 697 return 0; |
| 698 |
| 699 case WM_PAINT: |
| 700 hdc = BeginPaint(hwnd, &ps); |
| 701 /* dest */ |
| 702 rc = StretchDIBits(hdc, 0, 0, image_width, image_height, |
| 703 /* source */ |
| 704 0, 0, image_width, image_height, |
| 705 wimage_data, (BITMAPINFO *)bmih, |
| 706 /* iUsage: no clue */ |
| 707 0, SRCCOPY); |
| 708 EndPaint(hwnd, &ps); |
| 709 return 0; |
| 710 |
| 711 /* wait for the user to tell us when to quit */ |
| 712 case WM_CHAR: |
| 713 switch (wP) { /* only need one, so ignore repeat count */ |
| 714 case 'q': |
| 715 case 'Q': |
| 716 case 0x1B: /* Esc key */ |
| 717 PostQuitMessage(0); |
| 718 } |
| 719 return 0; |
| 720 |
| 721 case WM_LBUTTONDOWN: /* another way of quitting */ |
| 722 case WM_DESTROY: |
| 723 PostQuitMessage(0); |
| 724 return 0; |
| 725 } |
| 726 |
| 727 return DefWindowProc(hwnd, iMsg, wP, lP); |
| 728 } |
OLD | NEW |