--- /dev/null
+/*---------------------------------------------------------------------------
+
+ rpng - simple PNG display program rpng-win.c
+
+ This program decodes and displays PNG images, with gamma correction and
+ optionally with a user-specified background color (in case the image has
+ transparency). It is very nearly the most basic PNG viewer possible.
+ This version is for 32-bit Windows; it may compile under 16-bit Windows
+ with a little tweaking (or maybe not).
+
+ to do:
+ - handle quoted command-line args (especially filenames with spaces)
+ - have minimum window width: oh well
+ - use %.1023s to simplify truncation of title-bar string?
+
+ ---------------------------------------------------------------------------
+
+ Changelog:
+ - 1.00: initial public release
+ - 1.01: modified to allow abbreviated options; fixed long/ulong mis-
+ match; switched to png_jmpbuf() macro
+ - 1.02: added extra set of parentheses to png_jmpbuf() macro; fixed
+ command-line parsing bug
+ - 1.10: enabled "message window"/console (thanks to David Geldreich)
+
+ ---------------------------------------------------------------------------
+
+ Copyright (c) 1998-2001 Greg Roelofs. All rights reserved.
+
+ This software is provided "as is," without warranty of any kind,
+ express or implied. In no event shall the author or contributors
+ be held liable for any damages arising in any way from the use of
+ this software.
+
+ Permission is granted to anyone to use this software for any purpose,
+ including commercial applications, and to alter it and redistribute
+ it freely, subject to the following restrictions:
+
+ 1. Redistributions of source code must retain the above copyright
+ notice, disclaimer, and this list of conditions.
+ 2. Redistributions in binary form must reproduce the above copyright
+ notice, disclaimer, and this list of conditions in the documenta-
+ tion and/or other materials provided with the distribution.
+ 3. All advertising materials mentioning features or use of this
+ software must display the following acknowledgment:
+
+ This product includes software developed by Greg Roelofs
+ and contributors for the book, "PNG: The Definitive Guide,"
+ published by O'Reilly and Associates.
+
+ ---------------------------------------------------------------------------*/
+
+#define PROGNAME "rpng-win"
+#define LONGNAME "Simple PNG Viewer for Windows"
+#define VERSION "1.20 of 28 May 2001"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <windows.h>
+#include <conio.h> /* only for _getch() */
+
+/* #define DEBUG : this enables the Trace() macros */
+
+#include "readpng.h" /* typedefs, common macros, readpng prototypes */
+
+
+/* could just include png.h, but this macro is the only thing we need
+ * (name and typedefs changed to local versions); note that side effects
+ * only happen with alpha (which could easily be avoided with
+ * "ush acopy = (alpha);") */
+
+#define alpha_composite(composite, fg, alpha, bg) { \
+ ush temp = ((ush)(fg)*(ush)(alpha) + \
+ (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128); \
+ (composite) = (uch)((temp + (temp >> 8)) >> 8); \
+}
+
+
+/* local prototypes */
+static int rpng_win_create_window(HINSTANCE hInst, int showmode);
+static int rpng_win_display_image(void);
+static void rpng_win_cleanup(void);
+LRESULT CALLBACK rpng_win_wndproc(HWND, UINT, WPARAM, LPARAM);
+
+
+static char titlebar[1024], *window_name = titlebar;
+static char *progname = PROGNAME;
+static char *appname = LONGNAME;
+static char *icon_name = PROGNAME; /* GRR: not (yet) used */
+static char *filename;
+static FILE *infile;
+
+static char *bgstr;
+static uch bg_red=0, bg_green=0, bg_blue=0;
+
+static double display_exponent;
+
+static ulg image_width, image_height, image_rowbytes;
+static int image_channels;
+static uch *image_data;
+
+/* Windows-specific variables */
+static ulg wimage_rowbytes;
+static uch *dib;
+static uch *wimage_data;
+static BITMAPINFOHEADER *bmih;
+
+static HWND global_hwnd;
+
+
+
+
+int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
+{
+ char *args[1024]; /* arbitrary limit, but should suffice */
+ char *p, *q, **argv = args;
+ int argc = 0;
+ int rc, alen, flen;
+ int error = 0;
+ int have_bg = FALSE;
+ double LUT_exponent; /* just the lookup table */
+ double CRT_exponent = 2.2; /* just the monitor */
+ double default_display_exponent; /* whole display system */
+ MSG msg;
+
+
+ filename = (char *)NULL;
+
+
+ /* First reenable console output, which normally goes to the bit bucket
+ * for windowed apps. Closing the console window will terminate the
+ * app. Thanks to David.Geldreich@realviz.com for supplying the magical
+ * incantation. */
+
+ AllocConsole();
+ freopen("CONOUT$", "a", stderr);
+ freopen("CONOUT$", "a", stdout);
+
+
+ /* Next set the default value for our display-system exponent, i.e.,
+ * the product of the CRT exponent and the exponent corresponding to
+ * the frame-buffer's lookup table (LUT), if any. This is not an
+ * exhaustive list of LUT values (e.g., OpenStep has a lot of weird
+ * ones), but it should cover 99% of the current possibilities. And
+ * yes, these ifdefs are completely wasted in a Windows program... */
+
+#if defined(NeXT)
+ LUT_exponent = 1.0 / 2.2;
+ /*
+ if (some_next_function_that_returns_gamma(&next_gamma))
+ LUT_exponent = 1.0 / next_gamma;
+ */
+#elif defined(sgi)
+ LUT_exponent = 1.0 / 1.7;
+ /* there doesn't seem to be any documented function to get the
+ * "gamma" value, so we do it the hard way */
+ infile = fopen("/etc/config/system.glGammaVal", "r");
+ if (infile) {
+ double sgi_gamma;
+
+ fgets(tmpline, 80, infile);
+ fclose(infile);
+ sgi_gamma = atof(tmpline);
+ if (sgi_gamma > 0.0)
+ LUT_exponent = 1.0 / sgi_gamma;
+ }
+#elif defined(Macintosh)
+ LUT_exponent = 1.8 / 2.61;
+ /*
+ if (some_mac_function_that_returns_gamma(&mac_gamma))
+ LUT_exponent = mac_gamma / 2.61;
+ */
+#else
+ LUT_exponent = 1.0; /* assume no LUT: most PCs */
+#endif
+
+ /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */
+ default_display_exponent = LUT_exponent * CRT_exponent;
+
+
+ /* If the user has set the SCREEN_GAMMA environment variable as suggested
+ * (somewhat imprecisely) in the libpng documentation, use that; otherwise
+ * use the default value we just calculated. Either way, the user may
+ * override this via a command-line option. */
+
+ if ((p = getenv("SCREEN_GAMMA")) != NULL)
+ display_exponent = atof(p);
+ else
+ display_exponent = default_display_exponent;
+
+
+ /* Windows really hates command lines, so we have to set up our own argv.
+ * Note that we do NOT bother with quoted arguments here, so don't use
+ * filenames with spaces in 'em! */
+
+ argv[argc++] = PROGNAME;
+ p = cmd;
+ for (;;) {
+ if (*p == ' ')
+ while (*++p == ' ')
+ ;
+ /* now p points at the first non-space after some spaces */
+ if (*p == '\0')
+ break; /* nothing after the spaces: done */
+ argv[argc++] = q = p;
+ while (*q && *q != ' ')
+ ++q;
+ /* now q points at a space or the end of the string */
+ if (*q == '\0')
+ break; /* last argv already terminated; quit */
+ *q = '\0'; /* change space to terminator */
+ p = q + 1;
+ }
+ argv[argc] = NULL; /* terminate the argv array itself */
+
+
+ /* Now parse the command line for options and the PNG filename. */
+
+ while (*++argv && !error) {
+ if (!strncmp(*argv, "-gamma", 2)) {
+ if (!*++argv)
+ ++error;
+ else {
+ display_exponent = atof(*argv);
+ if (display_exponent <= 0.0)
+ ++error;
+ }
+ } else if (!strncmp(*argv, "-bgcolor", 2)) {
+ if (!*++argv)
+ ++error;
+ else {
+ bgstr = *argv;
+ if (strlen(bgstr) != 7 || bgstr[0] != '#')
+ ++error;
+ else
+ have_bg = TRUE;
+ }
+ } else {
+ if (**argv != '-') {
+ filename = *argv;
+ if (argv[1]) /* shouldn't be any more args after filename */
+ ++error;
+ } else
+ ++error; /* not expecting any other options */
+ }
+ }
+
+ if (!filename) {
+ ++error;
+ } else if (!(infile = fopen(filename, "rb"))) {
+ fprintf(stderr, PROGNAME ": can't open PNG file [%s]\n", filename);
+ ++error;
+ } else {
+ if ((rc = readpng_init(infile, &image_width, &image_height)) != 0) {
+ switch (rc) {
+ case 1:
+ fprintf(stderr, PROGNAME
+ ": [%s] is not a PNG file: incorrect signature\n",
+ filename);
+ break;
+ case 2:
+ fprintf(stderr, PROGNAME
+ ": [%s] has bad IHDR (libpng longjmp)\n",
+ filename);
+ break;
+ case 4:
+ fprintf(stderr, PROGNAME ": insufficient memory\n");
+ break;
+ default:
+ fprintf(stderr, PROGNAME
+ ": unknown readpng_init() error\n");
+ break;
+ }
+ ++error;
+ }
+ if (error)
+ fclose(infile);
+ }
+
+
+ /* usage screen */
+
+ if (error) {
+ int ch;
+
+ fprintf(stderr, "\n%s %s: %s\n\n", PROGNAME, VERSION, appname);
+ readpng_version_info();
+ fprintf(stderr, "\n"
+ "Usage: %s [-gamma exp] [-bgcolor bg] file.png\n"
+ " exp \ttransfer-function exponent (``gamma'') of the display\n"
+ "\t\t system in floating-point format (e.g., ``%.1f''); equal\n"
+ "\t\t to the product of the lookup-table exponent (varies)\n"
+ "\t\t and the CRT exponent (usually 2.2); must be positive\n"
+ " bg \tdesired background color in 7-character hex RGB format\n"
+ "\t\t (e.g., ``#ff7700'' for orange: same as HTML colors);\n"
+ "\t\t used with transparent images\n"
+ "\nPress Q, Esc or mouse button 1 after image is displayed to quit.\n"
+ "Press Q or Esc to quit this usage screen.\n"
+ "\n", PROGNAME, default_display_exponent);
+ do
+ ch = _getch();
+ while (ch != 'q' && ch != 'Q' && ch != 0x1B);
+ exit(1);
+ } else {
+ fprintf(stderr, "\n%s %s: %s\n", PROGNAME, VERSION, appname);
+ fprintf(stderr,
+ "\n [console window: closing this window will terminate %s]\n\n",
+ PROGNAME);
+ }
+
+
+ /* set the title-bar string, but make sure buffer doesn't overflow */
+
+ alen = strlen(appname);
+ flen = strlen(filename);
+ if (alen + flen + 3 > 1023)
+ sprintf(titlebar, "%s: ...%s", appname, filename+(alen+flen+6-1023));
+ else
+ sprintf(titlebar, "%s: %s", appname, filename);
+
+
+ /* if the user didn't specify a background color on the command line,
+ * check for one in the PNG file--if not, the initialized values of 0
+ * (black) will be used */
+
+ if (have_bg)
+ sscanf(bgstr+1, "%2x%2x%2x", &bg_red, &bg_green, &bg_blue);
+ else if (readpng_get_bgcolor(&bg_red, &bg_green, &bg_blue) > 1) {
+ readpng_cleanup(TRUE);
+ fprintf(stderr, PROGNAME
+ ": libpng error while checking for background color\n");
+ exit(2);
+ }
+
+
+ /* do the basic Windows initialization stuff, make the window and fill it
+ * with the background color */
+
+ if (rpng_win_create_window(hInst, showmode))
+ exit(2);
+
+
+ /* decode the image, all at once */
+
+ Trace((stderr, "calling readpng_get_image()\n"))
+ image_data = readpng_get_image(display_exponent, &image_channels,
+ &image_rowbytes);
+ Trace((stderr, "done with readpng_get_image()\n"))
+
+
+ /* done with PNG file, so clean up to minimize memory usage (but do NOT
+ * nuke image_data!) */
+
+ readpng_cleanup(FALSE);
+ fclose(infile);
+
+ if (!image_data) {
+ fprintf(stderr, PROGNAME ": unable to decode PNG image\n");
+ exit(3);
+ }
+
+
+ /* display image (composite with background if requested) */
+
+ Trace((stderr, "calling rpng_win_display_image()\n"))
+ if (rpng_win_display_image()) {
+ free(image_data);
+ exit(4);
+ }
+ Trace((stderr, "done with rpng_win_display_image()\n"))
+
+
+ /* wait for the user to tell us when to quit */
+
+ printf(
+ "Done. Press Q, Esc or mouse button 1 (within image window) to quit.\n");
+ fflush(stdout);
+
+ while (GetMessage(&msg, NULL, 0, 0)) {
+ TranslateMessage(&msg);
+ DispatchMessage(&msg);
+ }
+
+
+ /* OK, we're done: clean up all image and Windows resources and go away */
+
+ rpng_win_cleanup();
+
+ return msg.wParam;
+}
+
+
+
+
+
+static int rpng_win_create_window(HINSTANCE hInst, int showmode)
+{
+ uch *dest;
+ int extra_width, extra_height;
+ ulg i, j;
+ WNDCLASSEX wndclass;
+
+
+/*---------------------------------------------------------------------------
+ Allocate memory for the display-specific version of the image (round up
+ to multiple of 4 for Windows DIB).
+ ---------------------------------------------------------------------------*/
+
+ wimage_rowbytes = ((3*image_width + 3L) >> 2) << 2;
+
+ if (!(dib = (uch *)malloc(sizeof(BITMAPINFOHEADER) +
+ wimage_rowbytes*image_height)))
+ {
+ return 4; /* fail */
+ }
+
+/*---------------------------------------------------------------------------
+ Initialize the DIB. Negative height means to use top-down BMP ordering
+ (must be uncompressed, but that's what we want). Bit count of 1, 4 or 8
+ implies a colormap of RGBX quads, but 24-bit BMPs just use B,G,R values
+ directly => wimage_data begins immediately after BMP header.
+ ---------------------------------------------------------------------------*/
+
+ memset(dib, 0, sizeof(BITMAPINFOHEADER));
+ bmih = (BITMAPINFOHEADER *)dib;
+ bmih->biSize = sizeof(BITMAPINFOHEADER);
+ bmih->biWidth = image_width;
+ bmih->biHeight = -((long)image_height);
+ bmih->biPlanes = 1;
+ bmih->biBitCount = 24;
+ bmih->biCompression = 0;
+ wimage_data = dib + sizeof(BITMAPINFOHEADER);
+
+/*---------------------------------------------------------------------------
+ Fill in background color (black by default); data are in BGR order.
+ ---------------------------------------------------------------------------*/
+
+ for (j = 0; j < image_height; ++j) {
+ dest = wimage_data + j*wimage_rowbytes;
+ for (i = image_width; i > 0; --i) {
+ *dest++ = bg_blue;
+ *dest++ = bg_green;
+ *dest++ = bg_red;
+ }
+ }
+
+/*---------------------------------------------------------------------------
+ Set the window parameters.
+ ---------------------------------------------------------------------------*/
+
+ memset(&wndclass, 0, sizeof(wndclass));
+
+ wndclass.cbSize = sizeof(wndclass);
+ wndclass.style = CS_HREDRAW | CS_VREDRAW;
+ wndclass.lpfnWndProc = rpng_win_wndproc;
+ wndclass.hInstance = hInst;
+ wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
+ wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
+ wndclass.hbrBackground = (HBRUSH)GetStockObject(DKGRAY_BRUSH);
+ wndclass.lpszMenuName = NULL;
+ wndclass.lpszClassName = progname;
+ wndclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
+
+ RegisterClassEx(&wndclass);
+
+/*---------------------------------------------------------------------------
+ Finally, create the window.
+ ---------------------------------------------------------------------------*/
+
+ extra_width = 2*(GetSystemMetrics(SM_CXBORDER) +
+ GetSystemMetrics(SM_CXDLGFRAME));
+ extra_height = 2*(GetSystemMetrics(SM_CYBORDER) +
+ GetSystemMetrics(SM_CYDLGFRAME)) +
+ GetSystemMetrics(SM_CYCAPTION);
+
+ global_hwnd = CreateWindow(progname, titlebar, WS_OVERLAPPEDWINDOW,
+ CW_USEDEFAULT, CW_USEDEFAULT, image_width+extra_width,
+ image_height+extra_height, NULL, NULL, hInst, NULL);
+
+ ShowWindow(global_hwnd, showmode);
+ UpdateWindow(global_hwnd);
+
+ return 0;
+
+} /* end function rpng_win_create_window() */
+
+
+
+
+
+static int rpng_win_display_image()
+{
+ uch *src, *dest;
+ uch r, g, b, a;
+ ulg i, row, lastrow;
+ RECT rect;
+
+
+ Trace((stderr, "beginning display loop (image_channels == %d)\n",
+ image_channels))
+ Trace((stderr, "(width = %ld, rowbytes = %ld, wimage_rowbytes = %d)\n",
+ image_width, image_rowbytes, wimage_rowbytes))
+
+
+/*---------------------------------------------------------------------------
+ Blast image data to buffer. This whole routine takes place before the
+ message loop begins, so there's no real point in any pseudo-progressive
+ display...
+ ---------------------------------------------------------------------------*/
+
+ for (lastrow = row = 0; row < image_height; ++row) {
+ src = image_data + row*image_rowbytes;
+ dest = wimage_data + row*wimage_rowbytes;
+ if (image_channels == 3) {
+ for (i = image_width; i > 0; --i) {
+ r = *src++;
+ g = *src++;
+ b = *src++;
+ *dest++ = b;
+ *dest++ = g; /* note reverse order */
+ *dest++ = r;
+ }
+ } else /* if (image_channels == 4) */ {
+ for (i = image_width; i > 0; --i) {
+ r = *src++;
+ g = *src++;
+ b = *src++;
+ a = *src++;
+ if (a == 255) {
+ *dest++ = b;
+ *dest++ = g;
+ *dest++ = r;
+ } else if (a == 0) {
+ *dest++ = bg_blue;
+ *dest++ = bg_green;
+ *dest++ = bg_red;
+ } else {
+ /* this macro (copied from png.h) composites the
+ * foreground and background values and puts the
+ * result into the first argument; there are no
+ * side effects with the first argument */
+ alpha_composite(*dest++, b, a, bg_blue);
+ alpha_composite(*dest++, g, a, bg_green);
+ alpha_composite(*dest++, r, a, bg_red);
+ }
+ }
+ }
+ /* display after every 16 lines */
+ if (((row+1) & 0xf) == 0) {
+ rect.left = 0L;
+ rect.top = (LONG)lastrow;
+ rect.right = (LONG)image_width; /* possibly off by one? */
+ rect.bottom = (LONG)lastrow + 16L; /* possibly off by one? */
+ InvalidateRect(global_hwnd, &rect, FALSE);
+ UpdateWindow(global_hwnd); /* similar to XFlush() */
+ lastrow = row + 1;
+ }
+ }
+
+ Trace((stderr, "calling final image-flush routine\n"))
+ if (lastrow < image_height) {
+ rect.left = 0L;
+ rect.top = (LONG)lastrow;
+ rect.right = (LONG)image_width; /* possibly off by one? */
+ rect.bottom = (LONG)image_height; /* possibly off by one? */
+ InvalidateRect(global_hwnd, &rect, FALSE);
+ UpdateWindow(global_hwnd); /* similar to XFlush() */
+ }
+
+/*
+ last param determines whether or not background is wiped before paint
+ InvalidateRect(global_hwnd, NULL, TRUE);
+ UpdateWindow(global_hwnd);
+ */
+
+ return 0;
+}
+
+
+
+
+
+static void rpng_win_cleanup()
+{
+ if (image_data) {
+ free(image_data);
+ image_data = NULL;
+ }
+
+ if (dib) {
+ free(dib);
+ dib = NULL;
+ }
+}
+
+
+
+
+
+LRESULT CALLBACK rpng_win_wndproc(HWND hwnd, UINT iMsg, WPARAM wP, LPARAM lP)
+{
+ HDC hdc;
+ PAINTSTRUCT ps;
+ int rc;
+
+ switch (iMsg) {
+ case WM_CREATE:
+ /* one-time processing here, if any */
+ return 0;
+
+ case WM_PAINT:
+ hdc = BeginPaint(hwnd, &ps);
+ /* dest */
+ rc = StretchDIBits(hdc, 0, 0, image_width, image_height,
+ /* source */
+ 0, 0, image_width, image_height,
+ wimage_data, (BITMAPINFO *)bmih,
+ /* iUsage: no clue */
+ 0, SRCCOPY);
+ EndPaint(hwnd, &ps);
+ return 0;
+
+ /* wait for the user to tell us when to quit */
+ case WM_CHAR:
+ switch (wP) { /* only need one, so ignore repeat count */
+ case 'q':
+ case 'Q':
+ case 0x1B: /* Esc key */
+ PostQuitMessage(0);
+ }
+ return 0;
+
+ case WM_LBUTTONDOWN: /* another way of quitting */
+ case WM_DESTROY:
+ PostQuitMessage(0);
+ return 0;
+ }
+
+ return DefWindowProc(hwnd, iMsg, wP, lP);
+}
projects / synfig.git / blobdiff