make conversions between BitmapColor and sal_uInt8 explicit

Implicit conversions are a dangerous cause of confusion as seen
in http://markmail.org/thread/a4copx2di7cxeowg and require tricky
rewrites to work around them, this change cleans them up and
disables them for all code outside of the immutable binfilter.

1 files changed, 1 insertions, 1 deletions

diff --git a/sd/source/ui/slidesorter/view/SlsButtonBar.cxx b/sd/source/ui/slidesorter/view/SlsButtonBar.cxx
index d6f71505c345..ff088bf4675a 100644
--- a/sd/source/ui/slidesorter/view/SlsButtonBar.cxx
+++ b/sd/source/ui/slidesorter/view/SlsButtonBar.cxx
@@ -158,7 +158,7 @@ namespace {
                             static_cast<sal_Int32>(nValue * (1-nAlpha)),
                             0,
                             255));
-                    pBitmap->SetPixel(nY, nX, 255-sal_uInt8(nNewValue));
+                    pBitmap->SetPixelIndex(nY, nX, static_cast<sal_uInt8>(255-nNewValue));
                 }
         }
     }