To convert from 4-bits to 8-bits channel, one should multiply by 17.
Acked-by: Antoine Cellerier <dionoea@videolan.org>

(not on some specific operating system)
Pointed-out-by: Ramiro Polla <ramiro.polla@gmail.com>

Don't force an explicit --disable-libva. This was especially silly on
non-libVA platforms.

Signed-off-by: Christophe Mutricy <xtophe@videolan.org>

Signed-off-by: Christophe Mutricy <xtophe@videolan.org>

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

Use pkg-config to check for libmodplug, and check for version >= 0.8, which is needed for some functions like ModPlug_NumSamples(), ModPlug_GetMessage(), ModPlug_NumInstruments(), etc...
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

The check for presence has already done in configure.ac

It now autodetects the presence of libVA pkg:
It will fail if --enable-libva is defined and it is not present
It will be activated if nothing is specified and libVA pkg is present

Moreover, it will check the presence of the avcodec/libva.h

You cannot check HAVE_AVCODEC_VAAPI before including "avcodec.h"

This patch also takes into account opening a new skins at any time
(not just at initialization)

When refreshing a window area, the window mask must first be stripped of this
 area, because the new refresh may not result in the same mask being applied.

This patch corrects the following issues :
- an animated bitmap with transparency varying from one subimage to the next
  is now guaranteed the previous subimage won't leave any trace.
- a control that becomes invisible now means transparency is restored
 if no other controls exist for the same area (instead of an undefined and visually unpleasant area)