David Storey - Update on CSS support in Kestrel

Update on CSS support in Kestrel

Monday, 27. August 2007, 13:29:32

While Kestrel is getting ready to spread its wings, we are currently busy adding new features to Core-2 and deep into the QA process. I've already mentioned the CSS3 selectors are done and dusted, but what else is new since the last report? Not forgetting about CSS2.1, we've adding support for whitespace: pre-line;. This edges us ever closer to full CSS2.1 support.

CSS3 support is obviously not as advanced but is moving along with every build. background-size from the backgrounds and borders module is now supported with the -o- prefix. overflow-x and overflow-y from the basic box model module have been supported in builds for a while but not widely reported. This was one of the CSS3 properties that had started to become widely used, due to it being supported in IE, so it was essential to support for site compatibility reasons. It pops up many times in Korean web sites for example. The currentColor keyword has now been added from the colour module. This was already supported in Opera for SVG. This specifies a colour to be the same as the value of the color property or inherits the colour from the parent if no colour is specified. Keeping up Opera's reputation for great keyboard support, nav-index, nav-up, nav-down, nav-left and nav-right have been added from the basic user interface module. This allows control of which element will be targeted next when the user presses the corresponding key. The spec doesn't define what key to use for each, but suggests the direction arrows for keyboard use. This is especially useful when absolute positioning is used and the elements may not be displayed in source order. Also from the basic user interface module, outline-offset has been added to round off our outline support.

As well as these properties and the ones already reported, there has been numerous bug fixes to improve our compatibility with major sites. Hopefully we'll be able to add further CSS3 support as Kestrel matures into a release ready product. We are taking note of what properties developers want and we are assessing if they are ready to be implemented.

Opera on top of AfricaOpera Mini 4 Beta 2 and Mobile Web Design

Comments

Fyrd # 27. August 2007, 14:06

Cool stuff!

I'm sure you've heard the demand for multiple background images...is this coming or are you guys waiting for the spec to mature more first? If so, I'd suggest doing exactly what Safari does but with the -o- prefix.

Actually I was wondering if it would be possible to emulate multiple backgrounds by creating an SVG file (which could include multiple rasterized images) and setting the background image to that? (I believe it was mentioned that CSS SVG backgrounds will be supported in Kestrel)

dstorey # 27. August 2007, 14:10

It should be possible using SVG as a background image. I'll leave it as an exercise to the reader to make an example of that (even if you don't yet have a build that supports this

)

Fyrd # 27. August 2007, 14:17

Ooh, I think I'll try that! Hey, would it work on the Wii? (I seem to recall you mentioning it having some Kestrel features)

DjiXas # 27. August 2007, 15:17

Does Yahoo Search Marketing and MSN AdCenter already works in 9.5 with no problems at all?

Andrew Gregory # 27. August 2007, 15:27

In terms of CSS, the top of my list would be rgba/hsl/hsla colour support. Quickly followed by border-radius.

I have to say a peeve of mine is finding sites using overflow-x/y but not specifying just overflow anywhere!

It's very nice to hear o-x/y support confirmed.

Fyrd # 27. August 2007, 15:46

Okay, I've written up a test case. If you wouldn't mind, could you tell me if this page looks like this?

Daedalus # 27. August 2007, 16:24

Very nice to see background-size in there, should be quite fun to play with

I don't personally care very much about the other new stuff in this post, but it's good to have anyway.

And I too want border-radius, btw

vithar # 27. August 2007, 18:53

Please, please, test Kestrel carefuly and not release it until it will be ready.

Anonymous # 13. September 2007, 13:55

Peter Gasston writes:

Hi David,

It seems that background-size isn't implemented correctly; it seems to clip itself if the background-size is set to less than its original size, or repeat itself if set to larger - even if no-repeat is also set. Take a look at this page:

http://www.broken-links.com/tests/opera_bg.html

It displays correctly in Safari & Konqueror, but not in Kestrel. Curiously, the example page on CSS3.info:

http://www.css3.info/preview/background-size/

Displays as it should, and yet the code seems the same.

_Grey_ # 14. September 2007, 11:09

@Peter Gaston: I tested with Safari 3.0 on XP and Opera 9.5a3 and for me they display them the same, only that Safari uses Anti-Aliasing (looks nicer/smoother), while Opera doesn't.

I don't think that's what you mean, though, is it?

Anonymous # 14. September 2007, 16:16

Peter Gasston writes:

Problem is fixed in the latest Alpha.

Anonymous # 14. September 2007, 22:48

Peter Gasston writes:

Hmmm... actually, not in the Linux version I'm using; strange, I thought the rendering engine would be identical.

ndluthier # 28. October 2007, 21:17

Thanks for making CSS3 support a priority.

duncanbrown # 29. December 2007, 14:14

Hopefuly Kestrel will be a very good thing, so you guys don't rush into things and test everything carefuly first. It's good to hear that CSS3 support is being developed.

Profesjonalna # 20. January 2008, 01:45

David - in my last comment I thank You for great article and I must do it again:) Regards

deborahwebb # 12. February 2008, 12:07

Yes, don't be hasty and test everything carefully before releasing it. Although I must say that I can't wait to see the new Kestrel in action. Thanks for an interesting article anyway!

annmacgiff # 12. February 2008, 13:13

I keep waiting for the new Kerstrel to be released. It look like worth to be patient and wait until everything is perfect. I'm very interested in how will the CSS3 support look like.