Re: Changing the background of a 1 bit bitmap?

FROM : Glen Simmons
DATE : Mon Oct 04 19:58:53 2004

On 4 Oct, 2004, at 12:39 PM, R. Scott Thompson wrote:

>
> On Oct 4, 2004, at 11:25 AM, Glen Simmons wrote:
>

>> I'm creating an NSImage from some 1 bit bitmap data using the
>> -[NSBitmapImageRep initWithBitmapDataPlanes:pixelsWide: ...] method
>> passing NSCalibratedBlackColorSpace so that 1 bits become black
>> pixels and 0 bits become white pixels. I'd like the 0 bits to become
>> a color of my choice instead of white. Is there an easy way to do
>> this?

>
> What you want is a different Compositing operation
> (NSCompositeSourceOver I think).  There doesn't appear to be a way to
> do that with an NSImageView.  Perhaps you could create a custom view
> and use NSImage calls yourself?


I did say "easy". :-)  I was thinking this could be done at the time of
creation. The replacement color would always be the same, so I figured
some particular value passed as the colorSpaceName: parameter would do
it. Not so?

Glen