Resize of github.com before rendering completes causes scrambled text, graphics

[mikedilger]

Using current master, built fresh today, on a gentoo linux x86_64 system, running this:

./mach run --release -- -w http://github.com

seems to work fine if it is not resized until after the first render completes.

But if you resize it (I resize from bottom right corner) before rendering completes, the text and some graphics get quite scrambled.

EDIT: It may not be related to "before rendering completes". It seems to be hit or miss. I cannot consistently reproduce it, but I can reproduce it about 1 out of every 6 tries or so.

[metajack]

I assume this is webrender specific. Have you tried without -w?

cc @glennw @pcwalton

[mikedilger]

Without the -w I can't get it to happen, so yes probably webrender.

[kilobtye]

I can confirm this issue. And I would like to look into this issue.

[metajack]

@kilobtye Feel free to investigate. It's likely caused by the texture caches getting misused in webrender I think. Ping gw (@glennw) and @pcwalton in IRC if you have specific questions.

[kilobtye]

Thanks @metajack , it is about texture cache.
This issue is caused by text-shadow. Resize changes font-size and does text-shadow. Then

1. texture blur allocates textures but does not free.
2. texture becomes full and grows its size and messes up.
   I will submit a PR to fix a bug in 2, that should fix this issue.

[metajack]

Excellent sleuthing!