#define PROGNAME "rpng-win"
#define LONGNAME "Simple PNG Viewer for Windows"
#define VERSION "2.01 of 16 March 2008"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <windows.h>
#ifdef __CYGWIN__
#include <unistd.h>
#include <termio.h>
#include <sys/ioctl.h>
int repl_getch( void )
{
char ch;
int fd = fileno(stdin);
struct termio old_tty, new_tty;
ioctl(fd, TCGETA, &old_tty);
new_tty = old_tty;
new_tty.c_lflag &= ~(ICANON | ECHO | ISIG);
ioctl(fd, TCSETA, &new_tty);
fread(&ch, 1, sizeof(ch), stdin);
ioctl(fd, TCSETA, &old_tty);
return ch;
}
#define _getch repl_getch
#else
#include <conio.h>
#endif
#include "readpng.h"
#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); \
}
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];
static char *progname = PROGNAME;
static char *appname = LONGNAME;
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;
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];
char *p, *q, **argv = args;
int argc = 0;
int rc, alen, flen;
int error = 0;
int have_bg = FALSE;
double LUT_exponent;
double CRT_exponent = 2.2;
double default_display_exponent;
MSG msg;
filename = (char *)NULL;
#ifndef __CYGWIN__
AllocConsole();
freopen("CONOUT$", "a", stderr);
freopen("CONOUT$", "a", stdout);
#endif
#if defined(NeXT)
LUT_exponent = 1.0 / 2.2;
#elif defined(sgi)
LUT_exponent = 1.0 / 1.7;
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;
#else
LUT_exponent = 1.0;
#endif
default_display_exponent = LUT_exponent * CRT_exponent;
if ((p = getenv("SCREEN_GAMMA")) != NULL)
display_exponent = atof(p);
else
display_exponent = default_display_exponent;
argv[argc++] = PROGNAME;
p = cmd;
for (;;) {
if (*p == ' ')
while (*++p == ' ')
;
if (*p == '\0')
break;
argv[argc++] = q = p;
while (*q && *q != ' ')
++q;
if (*q == '\0')
break;
*q = '\0';
p = q + 1;
}
argv[argc] = NULL;
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])
++error;
} else
++error;
}
}
if (!filename)
++error;
if (error) {
#ifndef __CYGWIN__
int ch;
#endif
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"
#ifndef __CYGWIN__
"Press Q or Esc to quit this usage screen.\n"
#endif
"\n", PROGNAME, default_display_exponent);
#ifndef __CYGWIN__
do
ch = _getch();
while (ch != 'q' && ch != 'Q' && ch != 0x1B);
#endif
exit(1);
}
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);
}
if (error) {
#ifndef __CYGWIN__
int ch;
#endif
fprintf(stderr, PROGNAME ": aborting.\n");
#ifndef __CYGWIN__
do
ch = _getch();
while (ch != 'q' && ch != 'Q' && ch != 0x1B);
#endif
exit(2);
} else {
fprintf(stderr, "\n%s %s: %s\n", PROGNAME, VERSION, appname);
#ifndef __CYGWIN__
fprintf(stderr,
"\n [console window: closing this window will terminate %s]\n\n",
PROGNAME);
#endif
}
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 (have_bg) {
unsigned r, g, b;
sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);
bg_red = (uch)r;
bg_green = (uch)g;
bg_blue = (uch)b;
} 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);
}
if (rpng_win_create_window(hInst, showmode))
exit(2);
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"))
readpng_cleanup(FALSE);
fclose(infile);
if (!image_data) {
fprintf(stderr, PROGNAME ": unable to decode PNG image\n");
exit(3);
}
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"))
printf(
#ifndef __CYGWIN__
"Done. Press Q, Esc or mouse button 1 (within image window) to quit.\n"
#else
"Done. Press mouse button 1 (within image window) to quit.\n"
#endif
);
fflush(stdout);
while (GetMessage(&msg, NULL, 0, 0)) {
TranslateMessage(&msg);
DispatchMessage(&msg);
}
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;
wimage_rowbytes = ((3*image_width + 3L) >> 2) << 2;
if (!(dib = (uch *)malloc(sizeof(BITMAPINFOHEADER) +
wimage_rowbytes*image_height)))
{
return 4;
}
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);
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;
}
}
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);
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;
}
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))
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;
*dest++ = r;
}
} else {
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 {
alpha_composite(*dest++, b, a, bg_blue);
alpha_composite(*dest++, g, a, bg_green);
alpha_composite(*dest++, r, a, bg_red);
}
}
}
if (((row+1) & 0xf) == 0) {
rect.left = 0L;
rect.top = (LONG)lastrow;
rect.right = (LONG)image_width;
rect.bottom = (LONG)lastrow + 16L;
InvalidateRect(global_hwnd, &rect, FALSE);
UpdateWindow(global_hwnd);
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;
rect.bottom = (LONG)image_height;
InvalidateRect(global_hwnd, &rect, FALSE);
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:
return 0;
case WM_PAINT:
hdc = BeginPaint(hwnd, &ps);
rc = StretchDIBits(hdc, 0, 0, image_width, image_height,
0, 0, image_width, image_height,
wimage_data, (BITMAPINFO *)bmih,
0, SRCCOPY);
EndPaint(hwnd, &ps);
return 0;
case WM_CHAR:
switch (wP) {
case 'q':
case 'Q':
case 0x1B:
PostQuitMessage(0);
}
return 0;
case WM_LBUTTONDOWN:
case WM_DESTROY:
PostQuitMessage(0);
return 0;
}
return DefWindowProc(hwnd, iMsg, wP, lP);
}