739095 - Offscreen context without offscreen texture does not need YFlip

Status: RESOLVED FIXED

(Core :: Graphics, defect)

Description

[Oleg Romashin (:romaxa)]

When offscreen context bounded to texture with BindTexImage, it does not require YFlip.
So I think we should set YFlip only for offscreen gl context which  gl()->BindOffscreenNeedsTexture(mCanvasGLContext) == false

Comment 1

[Oleg Romashin (:romaxa)]

Attachment: Don't set YFlip for offscreen texture-less gl context

Comment 2

[Kelsey Gilbert [:jgilbert]]

Comment on attachment 609148 [details] [diff] [review]
Don't set YFlip for offscreen texture-less gl context

Review of attachment 609148 [details] [diff] [review]:
-----------------------------------------------------------------

Also, in order to land something touching yflip, we need to check that yflip is correct on the platforms the change touches. All core platform that can use OGL layers should be checked. These should be linux, mac, and mobile.

::: gfx/layers/opengl/CanvasLayerOGL.cpp
@@ +115,5 @@
>  
>      mCanvasGLContext = aData.mGLContext;
>      mGLBufferIsPremultiplied = aData.mGLBufferIsPremultiplied;
>  
> +    mNeedsYFlip = !gl()->BindOffscreenNeedsTexture(mCanvasGLContext);

The function you want is GLContext::GetOffscreenTexture().
BindOffscreenNeedsTexture() is a virtual function that controls whether OGL Layers needs to create its own texture. (and is probably coming out as we clean the provider classes)

Comment 3

[Oleg Romashin (:romaxa)]

Attachment: Don't set YFlip for offscreen texture-less gl context

Comment 4

[Oleg Romashin (:romaxa)]

https://hg.mozilla.org/integration/mozilla-inbound/rev/f65ae1a9074d

Comment 5

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/f65ae1a9074d