When using GAUSSIAN_NORMALS, image::resampleImage automatically unitizes
its output. This means that clients (e.g. mipgen) need to ensure that
the source image is in [-1,+1] rather than [0,+1].
* Overhaul the image library, Phase I.
The preps for our upcoming mipgen command line tool by adding filtering
capabilities and unit tests for a new LinearImage class, which will
subsume Image (deprecated).
Filament's new image library is composed of three components:
- LinearImage....simple 3D tensor of floats
- ImageOps.......free functions for simple transforms
- ImageSampler...high quality filtering
The old Image class was a simple untyped data blob and is now
deprecated. The new LinearImage class is always float32, and always
stores pixels in packed scanline order. This makes it easier to
implement image-based algorithms because they can be agnostic of the
underlying format.
Remaining refactorings:
- Phase II will migrate imageio to LinearImage
- Phase III will migrate all downstream tools to LinearImage
- Phase IV will remove old the Image class
* Image library code review feedback.
