Bug: b/160984428
Bug: b/163595585
Add support to SkAndroidCodec for decoding all frames with an
fSampleSize, so that an entire animation can be decoded to a smaller
size.
dm/:
- Test scaled + animated decodes
SkAndroidCodec:
- Make AndroidOptions inherit from SkCodec::Options. This allows
SkAndroidCodec to use fFrameIndex. (It also combines the two versions
of fSubset, which is now const for both.)
- Respect fFrameIndex, and call SkCodec::handleFrameIndex to decode
the required frame.
- Disallow decoding with kRespect + fFrameIndex > 0 if there is a
non-default orientation. As currently written (except without
disabling this combination), SkPixmapPriv::Orient would draw the new
portion of the frame on top of uninitialized pixels, instead of the
prior frame. This could be fixed by
- If SkAndroidCodec needs to decode the required frame, it could do so
without applying the orientation, then decode fFrameIndex, and then
apply the orientation.
- If the client provided the required frame, SkAndroidCodec would need
to un-apply the orientation to get the proper starting state, then
decode and apply.
I think it is simpler to force the client to handle the orientation
externally.
SkCodec:
- Allow SkAndroidCodec to call its private method handleFrameIndex. This
method handles decoding a required frame, if necessary. When called by
SkAndroidCodec, it now uses the SkAndroidCodec to check for/decode the
required frame, so that it will scale properly.
- Call rewindIfNeeded inside handleFrameIndex. handleFrameIndex calls a
virtual method which may set some state (e.g. in SkJpegCodec). Without
this change, that state would be reset by rewindIfNeeded.
- Simplify handling a kRestoreBGColor frame. Whether provided or not,
take the same path to calling zero_rect.
- Updates to zero_rect:
- Intersect after scaling, which will also check for empty.
- Round out instead of in - this ensures we don't under-erase
- Use kFill_ScaleToFit, which better matches the intent.
Change-Id: Ibe1951980a0dca8f5b7b1f20192432d395681683
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/333225
Commit-Queue: Leon Scroggins <scroggo@google.com>
Reviewed-by: Derek Sollenberger <djsollen@google.com>
fc4fdc5b25