counting message invocations.

Alan Grimes alangrimes at starpower.net
Thu Mar 25 23:59:40 UTC 2004


Andreas Raab wrote:

>>I _THINK_ I have a working non-bitBlit implementation...
>>    
>>
>
>I would advise STRONGLY against a non-bitBlt implementation in the general
>case (e.g., "improving" pixelAt: so that it doesn't use BitBlt). The reason
>being that BitBlt can deal with "forms" that don't even live in the Squeak
>universe (e.g., bitmaps on your native OS) that BitBlt will deal with lots
>of varying color formats, little endian forms and lots of other things.
>  
>

Okay, then here's an enhancement that could have saved me a heck of a 
lot of time:

Add to form > pixelAt:   the comment:

"If you need to do this many times, make your own instance of BitBlt as 
is done below and use it repeatedly. Look at 'senders of: BitBlt: 
bitPeekerFromForm: "

Benchmark wise, an implementation of the above wiped the floor with even 
my "FastColorConvert" which implemented a 100% custom implementation 
from the raw BitMap. =P

Currently the biggest hog in that part of the program is "rawLuminance" 
a custom addition to Color, which is basically the same as Luminance but 
without the weighting.




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