Tag: devblog

Ordering from Amazon the using Flow Browser

Being a big fan of online shopping, I’ve been keen to see when Flow could successfully complete a transaction on amazon.co.uk. It’s fair to say that online shopping is not a target use case for Flow, so I wasn’t going to get any engineering time dedicated to this; instead I was relying upon the product’s ongoing development to do the job for me.

Devblog: Fixed point vs floating point

I had an interesting problem with one of the sites I tried loading a while ago. weibo.com was using jQuery (version 1.7.2) which tries to detect browser features, and decided Flow was actually Internet Explorer. It later tried to use IE-specific filters rather than CSS opacity, so no fades worked. I tracked this down to jQuery’s startup code setting opacity to 0.55 and then getting it back out again. Since we converted 0.55 into 16.16 fixed point too early, it was retrieving it as 0.549988. That wasn’t equal to 0.55, and so jQuery decided Flow didn’t support opacity and therefore must be Internet Explorer.

Devblog: Rendering HTML/CSS on the GPU

When rendering web pages most browsers use a general purpose graphics library to do all their drawing. For example Chrome uses the Skia graphics library. This makes sense for cross platform browsers since they can use a single drawing API and leave the implementation details to the graphics library. The graphics library can try to optimise the drawing operations using some platform specific 2D hardware acceleration, or using a 3D library such as OpenGL/DirectX to take advantage of the GPU. If there is no hardware acceleration available the graphics library can do all the drawing in software using the CPU.

Devblog: Google Mail in a clean room browser

Google Mail (Basic HTML) screenshot

Flow only recently added limited HTML form support and that lets us log into Google. We hadn’t concentrated on forms as they’re barely, if ever, used in TV UIs and there was plenty of other stuff to get on with. Pleasingly, Google Mail (Basic HTML version) rendered very well the first time we were able to log in. Full Google Mail doesn’t work yet, but it makes sense to start with the basic mode first.

Devblog: From SVG browser to HTML browser

In 2006 we started writing a clean room SVG browser, primarily targeting set-top boxes. Back then, user interfaces were written in native code (usually ugly and inflexible) or HTML (very slow). We emphasised how it was equivalent to a web browser but, rather than an HTML parser with CSS box model layout, we parsed SVG markup. SVG takes negligible time to lay out and uses CSS sparsely, so we massively outperformed HTML browsers on equivalent UIs.