Add makefile.win32 and other minor changes for build on Windows

.gitignore

@@ -1,4 +1,5 @@
 *.o
+*.exe
 Makefile
 Makefile.in
 /aclocal.m4

README

@@ -14,7 +14,7 @@ Usage
 The options are controlled with simple key commands:
 
   d     Next webcam device
-  f     Toggle fullscreen view
+  f     Toggle fullscreen view (non-win32 only)
   i     Invert the colors
   c     Next color pair
   l     Increment line size
@@ -34,10 +34,15 @@ For systems where Autotools is supported, simply use:
     $ make
     $ make install # possibly as root depending on prefix
 
+For Windows, install Mingw and OpenCV and make sure their `bin`
+directories are the PATH environment variable.  Then edit the first
+variable in `win32/makefile.win32` to point to the installation prefix
+for you OpenCV installation.  After, change into the `win32` directory
+and run `mingw32-make -f makefile.win32`.  If everything went properly
+there should be a `digimag.exe` file in that directory.
+
 Dependencies
 ------------
 
-OpenCV 2.3 is used to grab frames from the webcam and process them.
-You'll need at least the `cxcore` and `highgui` libraries.
-
-OpenCV can be optained from: http://opencv.willowgarage.com
+OpenCV 2.3 is used to grab frames from the webcam and process them. It
+can be optained from: http://opencv.willowgarage.com

src/config.c

@@ -23,6 +23,10 @@
  * TODO: ensure this file is portable
  */
 
+#ifdef HAVE_WINDOWS
+#include <windows.h>
+#endif
+
 #include <string.h>
 #include <errno.h>
 #include <libgen.h>
@@ -159,12 +163,30 @@ static int on_ini_entry(void *user, const char *section, const char *name,
 }
 
 
+#ifdef HAVE_WINDOWS
+BOOL FileExists(LPCTSTR szPath)
+{
+  DWORD dwAttrib = GetFileAttributes(szPath);
+  return (dwAttrib != INVALID_FILE_ATTRIBUTES);
+}
+#endif
+
+
 static void config_create(void)
 {
   /* FIXME */
   char  command[PATH_MAX + 11] = { 0 };
   char *path = strdup(config_get_path());
+#ifdef HAVE_WINDOWS
+  if (FileExists(dirname(path)))
+    {
+      free(path);
+      return;
+    }
+  snprintf(command, PATH_MAX + 11, "mkdir \"%s\"", dirname(path));
+#else
   snprintf(command, PATH_MAX + 11, "mkdir -p \"%s\"", dirname(path));
+#endif
   (void) system(command);
   free(path);
 }

src/main.c

@@ -151,7 +151,14 @@ int main(int argc, char *argv[])
 
   open_device(conf);
 
-  cvNamedWindow(conf->title, 0);
+#ifndef HAVE_WINDOWS
+  cvNamedWindow(conf->title, CV_WINDOW_NORMAL | CV_WINDOW_KEEPRATIO);
+#else
+  /* Windows doesn't support fullscreen and doesn't keep aspect ration
+   * even with CV_WINDOW_KEEPRATIO. */
+  cvNamedWindow(conf->title, CV_WINDOW_AUTOSIZE | CV_WINDOW_KEEPRATIO);
+#endif
+
   cvSetMouseCallback(conf->title, on_mouse_callback, conf);
   handle = cvGetWindowHandle(conf->title);
   name = cvGetWindowName(handle);

win32/makefile.win32

@@ -0,0 +1,34 @@
+# Adjust this to where you installed OpenCV
+OPENCV_INSTALL_PREFIX = C:/OpenCV/install
+
+CFLAGS = \
+	-D_WIN32 -DHAVE_WINDOWS=1 \
+	-I$(OPENCV_INSTALL_PREFIX)/include/opencv \
+	-I$(OPENCV_INSTALL_PREFIX)/include
+
+LDFLAGS = \
+	-L$(OPENCV_INSTALL_PREFIX)/lib \
+	-lopencv_calib3d231 \
+	-lopencv_contrib231 \
+	-lopencv_core231 \
+	-lopencv_features2d231 \
+	-lopencv_flann231 \
+	-lopencv_gpu231 \
+	-lopencv_highgui231 \
+	-lopencv_imgproc231 \
+	-lopencv_legacy231 \
+	-lopencv_ml231 \
+	-lopencv_objdetect231 \
+	-lopencv_ts231 \
+	-lopencv_video231
+
+SOURCES = \
+	../src/main.c \
+	../src/ini.c ../src/ini.h \
+	../src/config.c ../src/config.h
+
+digimag.exe: $(SOURCES)
+	gcc $(CFLAGS) -o $@ $^ $(LDFLAGS)
+
+clean:
+	del digimag.exe