[RQt-devel] scale of view for some primitive doesn't work

[Michael Lawrence]

On Thu, Nov 11, 2010 at 7:32 PM, Tengfei Yin <yintengfei at gmail.com> wrote:

> So even when you use view$rotate(), the text direction won't change..is
> this also what we expected to see?
>
>
Yes. I can see how that may not always be desirable, but it would be tough
to work around it. That is, I cannot tease out the rotation from the rest of
the transformation. In the case of a word cloud, I think it would be
desirable, i.e., one is thinking of the text as glyphs that are independent
of the scales.


> and by the way, do you know any way to change to text size, the use case
> here is sth like "tag cloud", but I guess I can draw text as path to solve
> this problem.
>
>
Just change the font.. do you want some sort of vectorized "cex" argument to
qdrawText? Might not be that hard to add.

Michael


>
> On Thu, Nov 11, 2010 at 6:14 PM, Tengfei Yin <yintengfei at gmail.com> wrote:
>
>>
>>
>> On Thu, Nov 11, 2010 at 5:39 PM, Michael Lawrence <
>> lawrence.michael at gene.com> wrote:
>>
>>> This is by design. If this didn't work that way, then when the user
>>> zoomed into a chromosome, for example, the text labels would get really
>>> stretched out. Glyphs are the same way (they're essentially fancy
>>> characters). Zooming into a scatterplot should not make the glyphs larger.
>>> Circles (after much debate inside my head) behave the same as glyphs. This
>>> is because their radius, like in a bubble plot, is derived from something
>>> other than the X and Y axes.
>>>
>>> Shapes however, like rectangles, polygons and paths, are zoomed. You
>>> expect a mosaic plot rectangle or a map polygon to scale with the plot.
>>>
>>>
>> This make sense to me, in most cases, i guess people won't expect the
>> circle or text to be  zoomed in.
>>
>> Are you sure you really need the text to scale with the zoom? Deepayan and
>>> I decided a long time ago that zooming does not behave like a "magnifying
>>> glass." It rescales the plot.
>>>
>>>
>> No, you don't have to change that, it's convenient so far, I am just
>> curious why this doesn't work for text and circle, because in other rare
>> case, I will draw very small text as labels of axis for one circular track,
>> or if I draw points around the circular track, I am still expecting the
>> points will be zoomed in when I rescale the view. I guess I am confused the
>> "rescale of the view" with the one you defined with Deepayan, but it make
>> sense to me.
>>
>> There are some ways to get around this if you really want to:
>>> - Draw the text as a path.
>>> - Use the "render" method on the scene to render to a QPicture, rescale
>>> that and display it. This is how I imagined someone making a magnifying
>>> glass. QPicture is a vectorized representation, so no nasty scaling
>>> artifacts are introduced.
>>>
>>
>> Thanks, I think I need to do it in this way, if I really need them to be
>> rescaled.  I never try QPicture before, I will take a look at it.
>>
>>
>>> Michael
>>>
>>> On Thu, Nov 11, 2010 at 3:24 PM, Tengfei Yin <yintengfei at gmail.com>wrote:
>>>
>>>> Hi
>>>>
>>>> Here comes another question with text, please see the attached  code
>>>> below, only rect could be resized,  when I call v$scale()
>>>>
>>>> text, circle doesn't change. it happens to visnab, the circular view,
>>>> when I scale the view, every thing resize but the text, it's still in the
>>>> same size.
>>>>
>>>> library(qtpaint)
>>>> s <- qscene()
>>>> test_layer <- qlayer(s,function(layer,painter){
>>>>   qdrawRect(painter,30,30,70,70,stroke="blue")
>>>>   qdrawCircle(painter,50,50,20,stroke="red")
>>>>   qdrawText(painter,"TEST",50,50)
>>>> },limits=qrect(0,0,100,100))
>>>> v <- qplotView(s)
>>>> v$show()
>>>>
>>>> v$scale(1.5,1.5)
>>>>
>>>> Thanks
>>>>
>>>> Tengfei
>>>> --
>>>> Tengfei Yin
>>>> MCDB PhD student
>>>> 1620 Howe Hall, 2274,
>>>> Iowa State University
>>>> Ames, IA,50011-2274
>>>> Homepage: www.tengfei.name
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> Qtinterfaces-devel mailing list
>>>> Qtinterfaces-devel at lists.r-forge.r-project.org
>>>>
>>>> https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/qtinterfaces-devel
>>>>
>>>>
>>>
>>
>>
>> --
>> Tengfei Yin
>> MCDB PhD student
>> 1620 Howe Hall, 2274,
>> Iowa State University
>> Ames, IA,50011-2274
>> Homepage: www.tengfei.name
>>
>>
>>
>
>
> --
> Tengfei Yin
> MCDB PhD student
> 1620 Howe Hall, 2274,
> Iowa State University
> Ames, IA,50011-2274
> Homepage: www.tengfei.name
>
>
>
> _______________________________________________
> Qtinterfaces-devel mailing list
> Qtinterfaces-devel at lists.r-forge.r-project.org
>
> https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/qtinterfaces-devel
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