Issue 709331  has been merged into this issue.

 Issue 709329  has been merged into this issue.

 Issue 709328  has been merged into this issue.

Unable to reproduce the issue on the latest canary(59.0.3065.0) on MacBook Air OS 10.12.3. Attached is the screenshot.

Not sure, but if reproducible this looks to be specific to 10.11.6. 

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@ajha you need to run with --enable-experimental-web-platform-features, otherwise you're hitting Lea's polyfill on https://leaverou.github.io/conic-gradient/.

This is a Skia rendering artifact (for the GL backend specifically;  the software backend has its own issues).

@yiorsi@gmail.com just to confirm: your chrome://gpu/ shows "Rasterization: Hardware accelerated on all pages", right?

I'll open a Skia bug.

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Same issue. 

> just to confirm: your chrome://gpu/ shows "Rasterization: Hardware accelerated on all pages", right?

yes

@fmalita

The default chrome://gpu/ shows "Rasterization: Hardware accelerated"

When I disabled chrome://flags/#enable-gpu-rasterization, display effects such as sweep_cpu.png

Thanks.

Skia issue: http://bugs.skia.org/6470

@fmalita Thanks, and also has transparent Alpha problem

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@yiorsi@gmail.com

(I have not yet looked at the alpha difference very closely, it could be a valid issue)

Note that one of the stated limitations of Lea's polyfill is that interpolation is not performed in premultiplied space.  So the reference result you're using is likely not correct either.

Comparing to a linear gradient using the same colors: the new/native impl is correct and the difference you're seeing is due to the premul limitation in the conic polyfill.

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Thanks very much!

This is a better example for demonstrating this issue: http://dabblet.com/gist/51d6d879542fa5dc32376dd6b3f2585d

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There have been several improvements in Skia's gradient impl, and I believe these cases are now rendering with sharp transitions on both sw/gpu.

But the general case (multiple, uneven stops) is still blurry with GPU rasterization.  Merging into the master bug.