Re: CGShading

FROM : John C. Randolph
DATE : Tue Oct 12 22:29:38 2004

On Oct 12, 2004, at 12:30 PM, R. Scott Thompson wrote:



>>>>>  Here's some sample code that creates a pretty cool gradient by 
>>>>> using a Category for NSImage:
>>>>>
>>>>> <http://developer.apple.com/samplecode/Transformed_Image/

>>>>> Transformed_Image.html>
>>>>>
>>>>>

>>>
>>> When I wrote that code, CGShading wasn't available.  If I were 
>>> writing that sample today, I'd use GCShading.  I should also point 
>>> out that the code assumes that bytesPerRow == pixelsWide, which 
>>> isn't necessarily the case.
>>>

>>
>> Correction:  I meant to say it assumes that bytesPerRow  == 
>> (pixelsWide *  4), which isn't necessarily true.  In future versions 
>> of AppKit and CoreImage, bitmaps may get padded to allow for word or 
>> long word alignment for optimization.
>>

>
> Just a note, I don't think that CGShading will let you create the same 
> kind of gradient in the sample (at least not easily).


It can, you just need to use more than one gradient and composite one 
over the other.

-jcr





John C. Randolph <<email_removed>> (408) 974-8819
Sr. Cocoa Software Engineer,
Apple Worldwide Developer Relations
http://developer.apple.com/cocoa/index.html