implement background color

reduce flickering by keeping pixels if we know the background didn't change

panel text is now gone, it would require us to redraw every transparent
widget on top, which is a bad tradeoff since that panel text isn't very
useful anyway.

1 files changed, 24 insertions, 0 deletions

diff --git a/alf/alf.cpp b/alf/alf.cpp
index d40522f..311c65b 100644
--- a/alf/alf.cpp
+++ b/alf/alf.cpp
@@ -415,3 +415,27 @@ ALF_ShouldMessageBubble(HWND hwnd, UINT msg, WPARAM wparam, LPARAM lparam)
         || msg == WM_CTLCOLORLISTBOX || msg == WM_CTLCOLORSCROLLBAR
         || msg == WM_CTLCOLORSTATIC;
 }
+
+void
+ALF_FillRect(HDC dc, const RECT *rc, ALFColor color)
+{
+    if (color == ALF_COLOR_TRANSPARENT)
+        return;
+
+    COLORREF gdicolor = ALF_ColorToGdi(color);
+    COLORREF oldBkColor = SetBkColor(dc, gdicolor);
+    ExtTextOut(dc, 0, 0, ETO_OPAQUE, rc, NULL, 0, NULL);
+    SetBkColor(dc, oldBkColor);
+}
+
+COLORREF
+ALF_ColorToGdi(ALFColor color)
+{
+    if (color == ALF_COLOR_TRANSPARENT) {
+        return (COLORREF)-1;
+    } else if (color & 0x80000000) {
+        return GetSysColor((color & 0x7f000000) >> 24);
+    } else {
+        return (COLORREF)color;
+    }
+}