Lessons learned
1. ImageShader (correctly) always compresses (typically via PNG) during serialization. This has the surprise results of
- if the image was marked opaque, but has some non-opaque pixels (i.e. bug in blitter or caller), then compressing may "fix" those pixels, making the deserialized version draw differently. bug filed.
- 565 compressess/decompresses to 8888 (at least on Mac), which draws differently (esp. under some filters). bug filed.
2. BitmapShader did not enforce a copy for mutable bitmaps, but ImageShader does (since it creates an Image). Thus the former would see subsequent changes to the pixels after shader creation, while the latter does not, hence the change to the BlitRow test to avoid this modify-after-create pattern. I sure hope this prev. behavior was a bug/undefined-behavior, since this CL changes that.
BUG=skia:5595
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2195893002
Review-Url: https://codereview.chromium.org/2195893002
This also:
makes the SkLightingShader handle normal maps where the rects aren't aligned between the diffuse and normal maps.
adds a light aggregating class (Lights) to SkLightingShader (along with a Builder nested class).
Split out of https://codereview.chromium.org/1261433009/ (Add SkCanvas::drawLitAtlas call)
Review URL: https://codereview.chromium.org/1291783003
Additionally this CL:
forces the light colors to be opaque
forces the light direction to be normalized
adds a raster implementation
adds a gm
Review URL: https://codereview.chromium.org/1245883003
Reason for revert:
Compilation failures:
../../../../../samplecode/SampleLighting.cpp:13:18: fatal error: SkGr.h: No such file or directory
Original issue's description:
> Add normal map sample
>
> This adds an example of an SkShader that does normal
> mapping. It has a single directional light and an
> ambient light.
>
> Committed: https://skia.googlesource.com/skia/+/8e0da72ba890de395c9946ec6639c9e1e7b16027TBR=reed@google.com,bsalomon@google.com,jvanverth@google.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
Review URL: https://codereview.chromium.org/1230603002
This adds an example of an SkShader that does normal
mapping. It has a single directional light and an
ambient light.
Review URL: https://codereview.chromium.org/1212813009
