Text draw speed regression

[edvv]

Dear WinObjC Engineers,

From release 41 to 42 there is a regression in text drawing speed. Release 41 is about 10 to 100 times faster than 42. It is a very significant effect. Release 41 text draw speed was similar to an iPad, while Release 42 is an order of magnitude or two slower.

See also #1374

Sincerely,

Ed

[rajsesh]

@edvv could you please explain what text draw API you are seeing regression in? What formatting you are using and the contents?

[edvv]

@rajsesh-msft The API is that of the project at this URL:

#1335

Where [aString drawAtPoint:aPoint withAttributes:stringAttributes]; is called tens to hundreds of times for tables formatted as shown at this URL:

http://www.vvidget.org/manuals/GraphIDE/Controls/Tables/index.html

and while scrolling. It is noticeable by a user while scrolling, but is not particular to this situation.

Sincerely,

Ed

[edvv]

This problem persists with release 43.

[antoine-haas]

Thanks for trying it out with the new release @edvv. This is currently being investigated by #1374.

[rajsesh]

@eddv, thanks for reporting this. We had seen the regression internally as well. We will use #1374 for tracking perf issues. We will likely have to address these over a couple of iterations. For example, #1490 is also hit quite a bit in this code path.

[rajsesh]

#1374 won't fix all issues afterall, so we will keep this active for now.

[rajsesh]

Issue #1620 will improve the performance. We will re-evaluate perf after that work and iterate.