933577 - Optimize DrawTargetSkia::MaskSurface

Status: NEW

(Core :: Graphics, defect)

Description

[Andreas Gal :gal]

+++ This bug was initially created as a clone of Bug #933567 +++

mattwoodrow:

I think the best way to implement MaskSurface will be to use the secret features of drawBitmap().

drawBitmap normally draws the passed bitmap as a source, unless the bitmap is a8, in which case it will use the bitmap as a mask and use the SkPaint to decide the source.

Most of the time we should already have a8 bitmap as the mask surface, but we can call SkBitmap::extractAlpha() if we get some other sort of source.

Then the implementation should be more or less identical to FillRect() except passing mask, aOffset.x, aOffset.y instead of aRect.

Comment 1

[Andreas Gal :gal]

Attachment: Part 1: Factor out PaintSurface

Comment 2

[Andreas Gal :gal]

Attachment: Part 2: Change SourceSurfaceSkia::InitFromCanvas to InitFromBitmap

Comment 3

[Andreas Gal :gal]

Attachment: Part 3: Optimize MaskSurface

Comment 4

[Matt Woodrow (:mattwoodrow)]

Comment on attachment 825723 [details] [diff] [review]
Part 1: Factor out PaintSurface

Review of attachment 825723 [details] [diff] [review]:
-----------------------------------------------------------------

::: gfx/2d/DrawTargetSkia.cpp
@@ +328,5 @@
>  
>    SkRect sourceBoundingRect = RectToSkRect(boundingSource);
>    SkIRect sourceBoundingIRect = RectToSkIRect(boundingSource);
>  
> +  const SkBitmap& bitmap = static_cast<SourceSurfaceSkia*>(static_cast<SourceSurface*>(surface))->GetBitmap();

The inner static_cast should just be surface.get()

Comment 5

[Matt Woodrow (:mattwoodrow)]

Comment on attachment 825725 [details] [diff] [review]
Part 3: Optimize MaskSurface

Review of attachment 825725 [details] [diff] [review]:
-----------------------------------------------------------------

Looks good, as long as it works!

Comment 6

[BugBot [:suhaib / :marco/ :calixte]]

The bug assignee didn't login in Bugzilla in the last 7 months, so the assignee is being reset.