Thanks to I.Savant and George Orthwein, I can now colorize the
source image and then draw the tile to the view.
To make it faster I'd like to optimize the code, by only colorizing
one 8x8 'cell' at a time, rather than the full 128x128 image (as I
need to do it 25 x 40 times each time I refresh the display).
So my basic question is how can I create an NSImage, or
NSBitmapRepresentation, which contains just a specified rectangle of
a source image?
I've been all through the docs and can't figure out how to pull a
sepcific rectangle from an image, and store it in an NSImage or
NSBitmapRepresentation.
Any ideas?
-Kenny
On 30 Jun 2006, at 21:52, I. Savant wrote:
George:
Thanks for this - I hadn't considered that solution.
--
I.S.
On Jun 30, 2006, at 11:17 AM, George Orthwein wrote:
On Jun 30, 2006, at 10:36 AM, Kenny Millar wrote:
Because I need to change the foreground colour too, and every
location on
the 'screen' can have a different forground/background colour.
It would take two operations. You'd composite the text with
transparent background with a solid fill color as source, using
CompositeSourceIn. That colorizes the text and leaves the
transparency. Then you'd draw that over the background color. At
least, I think that should work. :)
If you can't add transparency, I just discovered -
colorizeByMappingGray:toColor:blackMapping:whiteMapping. It kinda
works for me but for some reason the white areas are using the
gray color instead of the specified white color. But I did end up
with custom back/foreground colors.
I'm surprised there is not an NSImage method for using a grayscale
image as a mask. Half the messages in the archives asking about
this topic reference CompositeSourceIn, but I see now that that
will only work if you already have some transparency. There do
seem to be some Quartz methods though: http://developer.apple.com/documentation/GraphicsImaging/
Conceptual/drawingwithquartz2d/dq_images/chapter_12_section_6.html
Looks like a good candidate for an NSBitmapImageRef category. :)
(though I don't actually know how difficult using the quartz calls
would be...)
George
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Cocoa-dev mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/idiotsavant2005%
40gmail.com
This email sent to email@hidden
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Cocoa-dev mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
http://lists.apple.com/mailman/options/cocoa-dev/email@hidden
