Convert GLHighContrastFilterEffect to an .fp file.
The fuzzer detected a bug in our handling of null child processors.
Rather than attempt to further tweak a hand-rolled effect, it seemed
more productive to convert it into a full-fledged .fp file. This
provides a very high degree of confidence that the basics are done
properly, for a relatively low amount of effort.
Contrast calculation has also been optimized slightly. The original
shader calculated (1+c/1-c) separately for every pixel. This is now done
once, in Make(). Also, if contrast adjustment is set to zero, the
contrast block is fully omitted.
Change-Id: I2af4708536b249e03c3ebede9b10fc1125eadb7b
Bug: oss-fuzz:24039
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/301942
Commit-Queue: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
9 files changed