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[pygame] Formal definitions for the BLEND operations
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
<len-l@xxxxxxxxx>