[Laszlo-dev] For Review: Change 20090430-maxcarlson-n Summary: Reduce calls to getTextDimension()

[P T Withington]

1) On line 301 of LzTextSprite, could you move your new check (for  
fixed line height) above the comment, with it's own comment, something  
like:

// If the font size has been set, we already know the line height

It's confusing in the place where it is right now.

2) But, I have a question about that too:  since we are trying to  
model swf semantics, will there ever be a case where there is a  
default font size for the <text> but the content, being HTML,  
specifies a larger font size?  In that case, is lineHeight meant to be  
the default font size, or the font that is in the content?

3) Rather than reusing styleKey, could you make a new key, say  
mdivKey, just so I understand that is what it is for?  Presumably the  
_sizedomcache should use that key, rather than the cacheFullKey?

4) On line 510 there is unreachable code.

5) Your comment above line 515 is a restatement of my comment below  
the line.  If you like yours better, how about sign and date it and  
delete mine?

6) If _measureTextContent is never called, maybe it should just go  
away?  Along with the comment in getTextDimension that says it it  
inlined?

Otherwise approved.

On 2009-04-30, at 18:00EDT, Max Carlson wrote:

> Change 20090430-maxcarlson-n by maxcarlson at Bank on 2009-04-30  
> 14:56:24 PDT
>    in /Users/maxcarlson/openlaszlo/trunk-clean
>    for http://svn.openlaszlo.org/openlaszlo/trunk
>
> Summary: Reduce calls to getTextDimension()
>
> Bugs Fixed: LPP-8016 - Performance differences between OL 4.0.x and  
> 4.3.x
>
> Technical Reviewer: ptw
> QA Reviewer: hminsky
>
> Details: LzSprite - Clear out additional cache to prevent leaks in IE.
>
> LzTextSprite - Cache lineheight when the CSS value is set directly  
> to prevent measuring it later.  Reuse measurement divs when the  
> style is equivalent.
>
> Tests: test/lztest/lztest-textheight.lzx? 
> debug=true&lzr=dhtml&lzt=testboth runs as before, webtop has around  
> half the number of calls to getTextDimension().
>
> Files:
> M      WEB-INF/lps/lfc/kernel/dhtml/LzSprite.js
> M      WEB-INF/lps/lfc/kernel/dhtml/LzTextSprite.js
>
> Changeset: http://svn.openlaszlo.org/openlaszlo/patches/20090430-maxcarlson-n.tar