1637437 - Recompute Backdrop-Filters Enabled State Whenever UseWebRender is Modified

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, defect, P3)

Description

[Erik Nordin [:nordzilla]]

[1635584] added logic to recompute backdrop-filter's enabled state in some places where UseWebRender is set.

This is not good for several reasons:

1. These functions are tightly coupled together and should really exist within the same function call.

2. It would be easy to accidentally miss a place where one is called, but not the other.

3. Anyone adding a new call to SetUseWebRender() would have to magically know to recompute backdrop-filter's state.

4. Adding a call to RecomputeBackdropFilterEnabledState() after every use of SetUseWebRender() would be wasteful, because we really only want to recompute if the value changed.

Having this functionality separated just feels like a defect waiting to happen (if you don't already consider it a defect itself).

This patch modifies the macros that generate the gfxVars such that SetUseWebRender can have a custom setter that only recomputes backdrop-filter's state if its UseWebRender's value changes.

Comment 1

[Erik Nordin [:nordzilla]]

Attachment: Bug 1637437 - Recompute backdrop-filter only when WebRender changes r=jrmuizel,emilio

• Modify the gfxVars generation macros to allow custom setters.
  • Remove previous manual calls to recompute backdrop filter.

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/090e5dcb0308
Recompute backdrop-filter only when WebRender changes r=jrmuizel

Comment 3

[Razvan Maries]

https://hg.mozilla.org/mozilla-central/rev/090e5dcb0308