add jpeg support for Gem under Windows

README.md

@@ -219,6 +219,7 @@ that case, but I haven't tested doing it like that. Sorry. Get a better OS...)
           mingw-w64-i686-ladspa-sdk mingw-w64-i686-lame \
           mingw-w64-i686-libsndfile mingw-w64-i686-libvorbis \
           mingw-w64-i686-lua mingw-w64-i686-toolchain \
+          mingw-w64-i686-libjpeg-turbo \
           rsync unzip wget
 
 5. Download the source code *(3-6 minutes)*  

externals/Makefile

@@ -642,6 +642,9 @@ $(gem_src)/Gem.dll: $(gem_src)/configure
 		CXXFLAGS="-DHAVE_S_STUFF_H" \
 		--host=i686-w64-mingw32 \
 		--without-ALL \
+		--with-jpeg \
+		--with-jpeg-cflags="-I/mingw32/include" \
+		--with-jpeg-libs="-L/mingw32/lib -ljpeg" \
 		--with-ftgl \
 		--with-ftgl-cflags="-I/mingw32/include -I/mingw32/include/freetype2" \
 		--with-ftgl-libs="-L/mingw32/lib -lftgl" \

packages/win32_inno/Makefile

@@ -118,6 +118,7 @@ lib_install:
 	install -p $(bin_src)/zlib1.dll $(DESTDIR)$(bindir)/
 	install -p $(bin_src)/libpcre-1.dll $(DESTDIR)$(bindir)/
 	install -p $(bin_src)/libgraphite2.dll $(DESTDIR)$(bindir)/
+	install -p $(bin_src)/libjpeg-8.dll $(DESTDIR)$(bindir)/
 	# Apparently these Gem dependencies must be in the bindir
 	# to be found on Windows
 	-install -p $(DESTDIR)/extra/Gem/gem_film*.dll $(DESTDIR)$(bindir)/