more portable rounding behavior - refs ##1454

2012-08-31 20:31:06 -07:00 · 2012-08-31 20:31:06 -07:00 · b8f6b16a56
commit b8f6b16a56
parent d054178a75
1 changed files with 1 additions and 1 deletions
--- a/src/graphics.cpp
+++ b/src/graphics.cpp
@ -117,7 +117,7 @@ void image_32::set_grayscale_to_alpha()
            unsigned b = (rgba >> 16) & 0xff;

            // magic numbers for grayscale
-            unsigned a = (int)((r * .3) + (g * .59) + (b * .11));
+            unsigned a = static_cast<unsigned>(std::ceil((r * .3) + (g * .59) + (b * .11)));

            row_from[x] = (a << 24)| (255 << 16) |  (255 << 8) | (255) ;
        }