[vtk-developers] Charts regressions

[Marcus D. Hanwell]

I merged the topic branch in this morning, and will be keeping a close
eye on the dashboards. If you take a look at the new baseline images I
hope you agree that they look better (and are pretty much what I was
aiming for). It is important to have the charts use font metrics to do
as much of the layout as possible so that any font size/string length
should be displayed correctly.

Let me know what you think of it.

Marcus

On Sun, Oct 17, 2010 at 11:28 PM, Bill Lorensen <bill.lorensen at gmail.com> wrote:
> Thanks. You are correct I did not mean to send it to the arb.
>
> And, I guess I forgot I had mentioned this before.
>
> I'll look forward to the new code.
>
> Bill
>
> On Sun, Oct 17, 2010 at 6:24 PM, Marcus D. Hanwell
> <marcus.hanwell at kitware.com> wrote:
>> On Sun, Oct 17, 2010 at 3:24 PM, Bill Lorensen <bill.lorensen at gmail.com>
>> wrote:
>>>
>>> Sorry, I did mean to send this to arb at vtk.org. gmail was overly agressive.
>>
>> Do you mean you didn't mean to send this to arb at ...? I was wondering why it
>> was an ARB issue.
>>>
>>> Marcus,
>>>
>>> I noticed a while back on the wiki examples that the y axis label does
>>> not fit on the window for vtk charts. I'm not sure when this
>>> regression occurred since we don't update VTK every night.
>>
>> I remember you emailing me about this, and I gave you an overview of what I
>> was doing at the time. Due to my travel schedule, and some other events, my
>> topic branch to address this has been a little delayed. I had most of it
>> staged last week, but was working on fixing a few more regressions before
>> merging it. I think I got most of it finished yesterday.
>>>
>>> I looked at the VTKData git repository. On 8/23, many Charts baselines
>>> were changed.
>>>
>>> Please compare this baseline:
>>>
>>> http://vtk.org/gitweb?p=VTKData.git;a=blob;f=Baseline/Charts/TestScatterPlot.png;hb=e293ebc8db06c21a574f42911b27b9b8c92c6a95
>>> with this baseline
>>>
>>> http://vtk.org/gitweb?p=VTKData.git;a=blob;f=Baseline/Charts/TestScatterPlot.png;hb=fcdb83896ab1de8ec8efcb10bf5a079f2c7219f7
>>>
>>> The former looks correct to me. The Y-Axis lies completely in the
>>> window, while the later looks wrong to me. The Y-Axis label is
>>> truncated.
>>
>> The problem is that it was only correct for short strings, for longer ones
>> they would still fall off the edge. The newer code uses font metrics to
>> determine the chart layout and works for all font sizes and string lengths.
>> The issue was that only the Qt label render strategy was respecting the
>> rotation, but the freetype strategy was returning the wrong metrics and not
>> rotating the font.
>>>
>>> This occurs consistently on all of the baselines that hav ea Y-Axis labe;.
>>>
>> It looks a lot better when using the Qt label render strategy, and as I said
>> I was working on getting this into shape with the freetype rendering (which
>> is default for most VTK applications. The StringToImage topic branch
>> contains a lot of these changes, and there are a few more I will push
>> shortly and integrate tomorrow.
>> I didn't want to cause all of the baseline images to need multiple updates,
>> but once I merge the changes in tomorrow many tests will require updates. I
>> think the new baselines look far better, and I am hoping to land some more
>> string rendering improvements in master over the next few weeks. I did not
>> intend to leave the axis rendering like this for a release.
>> I hope that clears things up, these changes would have likely made it in
>> last week if it weren't for some other large changes also being integrated
>> along with some other timing issues.
>> Marcus
>