Re: Thoughts about a new GdkPixbuf transform interface

Bill Haneman wrote:
 - You have end up with a choice for the pipeline of:

  [1]  - Pixel based. Possibly incredibly slow and inefficient
      when you have steps that base one destination pixel
      on multiple source pixels.

  [2]  - Do the whole image at each step of the pipeline.
      Easy, fast, but you don't get any memory usage 
      savings over a simpler interface without filter
  [3]  - Tile based. Complex, complex, complex.
Yep.  My suggestion would be to choose implementation #2 first, but 
build the APIs with #2 in mind, so that enterprising people could patch
M-m-m... I'm working on this stuff because I need it. I know what I need:
- arbitrary affine transform, speed
- clear code
- drawing (lines etc)
- clipping region

Now I'm looking at your discussion of #1-2-3 and can't help but think: who will need it?..
There are two ways of chaining transformations:
1. Write new algorithm that contain two transformations at once
2. Apply first, then second
You can't do 1 in general case. You can do 2, but result is loss of quality (example: two
rotations in a row, result is worse then one rotation on angle1+angle2). Why build the
whole new 'tile' infrastructure to have the result identical (bad) to just applying two
transformations? 30% memory saving (large images: src+dest+tmpbuffer, last eliminated)?

But I rather consider reasonable to derive from Transformation object.

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