Pin to 0 and 255. Don't roll over. Or is there something else?
On Tue, Feb 10, 2009 at 11:11 AM, Lenard Lindstrom <[email protected]> wrote: > Hi, > > I am trying to write unit tests for the blit blend operations and am > running into problems. There are no formal definitions as to what exactly a > BLEND_ADD, BLEND_SUB and BLEND_MULT do. Sure they are add, subtract and > multiply. But what happens with overflow and underflow. Do they truncate or > just return maximum or minimum values. I will not look as the source for the > answers because then I would just write the tests to pass rather than making > tests that reflect the original intent of the operations. > > Lenard > > -- > Lenard Lindstrom > <[email protected]> > >
