From b0b625b79605ab0a18aa038f3f87e88da2441c16 Mon Sep 17 00:00:00 2001 From: Leon Scroggins III Date: Thu, 22 Dec 2016 16:40:24 -0500 Subject: GIF: Better check for frame dependency If a frame does not have a valid transparent index and it covers the prior frame, it does not really depend on that frame. Instead, it depends on the frame that the prior frame depends on. Determine this once we have parsed the local color map (if any), so a transparent index out of range of the color map is not considered valid. Share code that determines whether a frame has a transparent pixel. Add a test that we compute the dependencies correctly. randPixelsAnim.gif has 13 frames. After the first, the frames cover all combinations of - Whether the prior frame was keep, restoreBG or restoreToPrevious - Whether the new frame covers the prior frame - Whether the new frame has a transparent pixel (It only does so when using a global color table. It may make sense to expand the test to also cover using local color tables.) The test caught a bug where we incorrectly reused an existing SkColorTable for a different frame. Fix that bug by keeping track of the transparent index associated with the current SkColorTable. Change-Id: I3cf6be7f612990fa7a00d9e74d116d31bd227526 Reviewed-on: https://skia-review.googlesource.com/6402 Reviewed-by: Matt Sarett Commit-Queue: Leon Scroggins --- resources/randPixelsAnim.gif | Bin 0 -> 1225 bytes 1 file changed, 0 insertions(+), 0 deletions(-) create mode 100644 resources/randPixelsAnim.gif (limited to 'resources') diff --git a/resources/randPixelsAnim.gif b/resources/randPixelsAnim.gif new file mode 100644 index 0000000000..7b12bfc6f6 Binary files /dev/null and b/resources/randPixelsAnim.gif differ -- cgit v1.2.3