[RQt-devel] par(xpd=NA) and the layout approach in qtpaint

Yihui Xie xie at yihui.name
Wed Sep 1 17:49:05 CEST 2010 

Ahhh! cache!!! again! It brought me a problem that I could not solve
for months... sigh... I've been wondering why I'm not able to draw a
gray background with grid like ggplot2 exactly at the locations I
specified (near the margins) -- some parts of the gray rectangles just
do not show up no matter how large a limit I designate to the layer,
as Tengfei suggested to me in the last email (I know that approach,
but it just does not work).

Thanks a lot! The pain that I was unable to explain to Di has finally gone...

Regards,
Yihui
--
Yihui Xie <xieyihui at gmail.com>
Phone: 515-294-2465 Web: http://yihui.name
Department of Statistics, Iowa State University
2215 Snedecor Hall, Ames, IA



On Wed, Sep 1, 2010 at 10:31 AM, Michael Lawrence
<lawrence.michael at gene.com> wrote:
>
>
> On Wed, Sep 1, 2010 at 6:54 AM, Yihui Xie <xie at yihui.name> wrote:
>>
>> Thanks! That was my guess, but it does not seem to work, e.g.:
>>
>
> I would suggest turning off caching, i.e., pass cache=FALSE to qlayer, at
> least for the two axes. The issue, I think, is that Qt will only allocate a
> buffer large enough for the layer. You're then drawing outside of the cache,
> and it never makes it to the screen. I might make clip and cache both
> default to FALSE.  Caching usually only makes sense when there is a dynamic
> overlay on the layer. This is usually not the case for axes.
>
> Michael
>
>>
>> # all layers with clip=FALSE but still get clipped
>> library(qtpaint)
>> scene = qscene()
>> figLayer = qlayer(scene, clip = FALSE)
>> titlePainter = function(item, painter) {
>>    qdrawText(painter, paste(rep("The Useless Title", 5), collapse = " -
>> "),
>>        300, 10, "center", "center")
>> }
>> yAxisPainter = function(item, painter) {
>>    qdrawText(painter, as.character(pretty(1:400)), 37.5, pretty(1:400))
>> }
>> plotPainter = function(item, painter) {
>>    qdrawPoint(painter, runif(1000, 0, 600), runif(1000, 0, 400))
>>    qdrawRect(painter, 1, 1, 600 - 1, 400 - 1)
>> }
>> xAxisPainter = function(item, painter) {
>>    qdrawText(painter, as.character(pretty(1:600)), pretty(1:600),
>>        37.5)
>> }
>> mouseLocator = function(item, event) {
>>    print(as.numeric(event$pos()))
>> }
>> titleLayer = qlayer(figLayer, titlePainter, mousePressFun = mouseLocator,
>>    limits = qrect(0, 0, 600, 20), clip = FALSE, row = 0, col = 1)
>> yaxis = qlayer(figLayer, yAxisPainter, mousePressFun = mouseLocator,
>>    limits = qrect(0, 0, 75, 400), clip = FALSE, row = 1, col = 0)
>> plotLayer = qlayer(figLayer, plotPainter, mousePressFun = mouseLocator,
>>    limits = qrect(0, 0, 600, 400), clip = FALSE, row = 1, col = 1)
>> xaxis = qlayer(figLayer, xAxisPainter, mousePressFun = mouseLocator,
>>    limits = qrect(0, 0, 600, 75), clip = FALSE, row = 2, col = 1)
>>
>> layout = figLayer$gridLayout()
>>
>> layout$setRowStretchFactor(0, 1)
>> layout$setRowStretchFactor(1, 5)
>> layout$setRowStretchFactor(2, 1)
>> layout$setColumnStretchFactor(0, 1)
>> layout$setColumnStretchFactor(1, 5)
>>
>> print(view <- qplotView(scene = scene))
>>
>>
>> Regards,
>> Yihui
>> --
>> Yihui Xie <xieyihui at gmail.com>
>> Phone: 515-294-6609 Web: http://yihui.name
>> Department of Statistics, Iowa State University
>> 2215 Snedecor Hall, Ames, IA
>>
>>
>>
>> On Wed, Sep 1, 2010 at 7:26 AM, Hadley Wickham <hadley at rice.edu> wrote:
>> > For the answer to your first question, turning clipping off for that
>> > layer.
>> >
>> > Hadley
>> >
>> > On Wednesday, September 1, 2010, Yihui Xie <xie at yihui.name> wrote:
>> >> Hi all,
>> >>
>> >> I'm wondering if there are any approaches to completely show the
>> >> graphical elements on the boundaries under a layout containing several
>> >> layers. This is like the functionality par(xpd=NA) in base R graphics.
>> >> See the example below that the texts for the origin (0,0) on the axes
>> >> are partially hidden.
>> >>
>> >> My another problem is, I don't really understand the layout approach,
>> >> although I've been reading the qtpaint vignette and digging the Nokia
>> >> Qt documentations. Specifically, how should we define the coordinate
>> >> system in each layer in a layout? (I experimented with mouse clicking
>> >> to get locations but got even more confused) With a single layer, I
>> >> can plot the data using its range to define the limits and everything
>> >> is fine. Besides, does anyone have a working demo to draw a simplest
>> >> plot with the layout approach? I struggled with
>> >> set(Column|Row)(Maximum|Minimum|Preferred)(Width|Height) and
>> >> set(Column|Row)StretchFactor, but they do not behave as we expect them
>> >> to, e.g. the stretch factor being 0 will not restrict the height/width
>> >> of a layer to be a fixed value -- they change as we resize the window.
>> >>
>> >> Below is the R code:
>> >>
>> >> # I need hints on how to split the root layer into several regions
>> >> # and what are their coordinate systems
>> >> library(qtpaint)
>> >> scene = qscene()
>> >> figLayer = qlayer(scene,limits=qrect(0,0,675,550))
>> >> titlePainter = function(item, painter) {
>> >>     qdrawText(painter, 'The Useless Title', 300, 0,'center','bottom')
>> >>     tmp=as.matrix(titleLayer$boundingRect())
>> >>     qdrawRect(painter, tmp[1,1],tmp[1,2],tmp[2,1],tmp[2,2])
>> >> }
>> >> yAxisPainter = function(item, painter) {
>> >>     qdrawText(painter, as.character(pretty(1:400)), 37.5,
>> >> pretty(1:400))
>> >> }
>> >> plotPainter = function(item, painter) {
>> >>     qdrawPoint(painter, runif(1000, 0, 600), runif(1000, 0, 400))
>> >>     qdrawRect(painter, 1, 1, 600-1, 400-1)
>> >> }
>> >> xAxisPainter = function(item, painter) {
>> >>     qdrawText(painter, as.character(pretty(1:600)), pretty(1:600),
>> >> 37.5)
>> >> }
>> >> mouseLocator = function(item, event){
>> >>     print(as.numeric(event$pos()))
>> >> }
>> >> titleLayer = qlayer(figLayer, titlePainter,
>> >> mousePressFun=mouseLocator, row=2,col=1)
>> >> yaxis = qlayer(figLayer, yAxisPainter,mousePressFun=mouseLocator,row =
>> >> 1,col=0)
>> >> plotLayer = qlayer(figLayer, plotPainter,
>> >> mousePressFun=mouseLocator,row = 1, col = 1)
>> >> xaxis = qlayer(figLayer, xAxisPainter, mousePressFun=mouseLocator,row
>> >> = 0, col = 1)
>> >>
>> >> layout = figLayer$gridLayout()
>> >>
>> >> layout$setRowMaximumHeight(0, 75)
>> >> layout$setRowMinimumHeight(0, 60)
>> >> # main plot region: 400x600
>> >> layout$setRowPreferredHeight(1, 400)
>> >> layout$setRowMaximumHeight(2, 75)
>> >> layout$setRowMinimumHeight(2, 60)
>> >>
>> >> layout$setColumnMaximumWidth(0, 75)
>> >> layout$setColumnMinimumWidth(0, 60)
>> >> layout$setColumnPreferredWidth(1, 600)
>> >> layout$setRowStretchFactor(0, 0)
>> >> layout$setRowStretchFactor(1, 1)
>> >> layout$setRowStretchFactor(2, 0)
>> >> layout$setColumnStretchFactor(0, 0)
>> >> layout$setColumnStretchFactor(1, 1)
>> >>
>> >> print(view<-qplotView(scene = scene))
>> >>
>> >>
>> >> #################################################
>> >>
>> >>> sessionInfo()
>> >> R version 2.11.1 (2010-05-31)
>> >> x86_64-pc-linux-gnu
>> >>
>> >> locale:
>> >> [1] en_US.utf8
>> >>
>> >> attached base packages:
>> >> [1] stats     graphics  grDevices utils     datasets  methods   base
>> >>
>> >> other attached packages:
>> >> [1] qtpaint_0.7.9
>> >>
>> >> loaded via a namespace (and not attached):
>> >> [1] qtbase_0.8-4 tools_2.11.1
>> >>
>> >>
>> >> Thanks a lot!
>> >>
>> >> Regards,
>> >> Yihui
>> >> --
>> >> Yihui Xie <xieyihui at gmail.com>
>> >> Phone: 515-294-6609 Web: http://yihui.name
>> >> Department of Statistics, Iowa State University
>> >> 3211 Snedecor Hall, Ames, IA
>> >> _______________________________________________
>> >> 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
>> >>
>> >
>> > --
>> > Assistant Professor / Dobelman Family Junior Chair
>> > Department of Statistics / Rice University
>> > http://had.co.nz/
>> >
>> _______________________________________________
>> 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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