X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/5a566d89be51576b079dc1b7940304390d11b950..61c213fe224da24ce33c9187263e75a17ca83a04:/samples/image/image.cpp

diff --git a/samples/image/image.cpp b/samples/image/image.cpp
index 8dca999ea3..7bfe2db778 100644
--- a/samples/image/image.cpp
+++ b/samples/image/image.cpp
@@ -184,7 +184,7 @@ public:
                 wxBMP_24BPP
             };
 
-            static const wxString bppchoices[] =
+            const wxString bppchoices[] =
             {
                 _T("1 bpp color"),
                 _T("1 bpp B&W"),
@@ -229,7 +229,7 @@ public:
                 wxPNG_TYPE_GREY_RED,
             };
 
-            static const wxString pngchoices[] =
+            const wxString pngchoices[] =
             {
                 _T("Colour 8bpp"),
                 _T("Colour 16bpp"),
@@ -305,7 +305,7 @@ public:
             return;
         }
 
-//        data.UseAlpha();
+        data.UseAlpha();
 
         Data::Iterator p(data);
 
@@ -319,10 +319,12 @@ public:
 
             for ( int x = 0; x < REAL_SIZE; ++x )
             {
-                p.Red() = r;
-                p.Green() = g;
-                p.Blue() = b;
-                p.Alpha() = (Data::Iterator::ChannelType)((x*255.)/REAL_SIZE);
+                // note that RGB must be premultiplied by alpha
+                unsigned a = (Data::Iterator::ChannelType)((x*255.)/REAL_SIZE);
+                p.Red() = r * a / 256;
+                p.Green() = g * a / 256;
+                p.Blue() = b * a / 256;
+                p.Alpha() = a;
 
                 ++p; // same as p.OffsetX(1)
             }