Hi
baptiste auguie wrote:
Very nice, thank you for this great addition to R graphics! I can't
wait to see lattice and ggplot2 functions that use rasterGrob to
display images. The pdf output is so much better in every way!
Incidentally, I ran into a segfault with grid.cap on the quartz
device, but maybe it's normal at this stage.
This may be due to the fact that I tested the changes on Mac OS X 10.6
(looks like you have 10.5 ?), plus the fact that I am feeling my way a
bit on the Mac. I have access to a 10.4 machine so I will try to take a
look there. Thanks for the report.
Paul
This works fine:
library(grid)
x11()
grid.text("test")
cap <- grid.cap()
This doesn't:
library(grid)
quartz()
grid.text("test")
cap <- grid.cap()
*** caught segfault ***
address 0x18330001, cause 'memory not mapped'
Traceback:
1: .Call(fnname, ..., PACKAGE = "grid")
2: grid.Call("L_cap")
3: grid.cap()
Possible actions:
1: abort (with core dump, if enabled)
2: normal R exit
3: exit R without saving workspace
4: exit R saving workspace
[R.app GUI 1.30 (5527) i386-apple-darwin9.8.0]
sessionInfo()
R version 2.11.0 Under development (unstable) (2009-11-30 r50622)
i386-apple-darwin9.8.0
locale:
[1] en_GB.UTF-8/en_GB.UTF-8/C/C/en_GB.UTF-8/en_GB.UTF-8
attached base packages:
[1] stats graphics grDevices utils datasets methods base
Best regards,
baptiste
2009/12/1 Paul Murrell <p.murr...@auckland.ac.nz>:
Hi
This is for developers of extension packages that provide extra *graphics
devices* for R.
In the *development* version of R, support has been added to the graphics
engine for sending raster images (bitmaps) to a graphics device. This
consists mainly of two new device functions: dev_Raster() and dev_Cap().
The R_GE_version constant (in GraphicsEngine.h) has been bumped up to 6 as a
marker of this change.
This means that, at a minimum, all graphics devices should be updated to
provide dummy implementations of these new functions that just say the
feature is not yet implemented (see for example the PicTeX and XFig devices
in the 'grDevices' package).
A full implementation of dev_Raster() should be able to draw a raster image
(provided as an array of 32-bit R colors) at any size, possibly (bilinear)
interpolated (otherwise nearest-neighbour), at any orientation, and with a
per-pixel alpha channel. Where these are not natively supported by a
device, the graphics engine provides some routines for scaling and rotating
raster images (see for example the X11 device). The dev_Cap() function
should return a representation of a raster image captured from the current
device. This will only make sense for some devices (see for example the
Cairo device in the 'grDevices' package).
A little more information and a couple of small examples are provided at
http://developer.r-project.org/Raster/raster-RFC.html
Paul
--
Dr Paul Murrell
Department of Statistics
The University of Auckland
Private Bag 92019
Auckland
New Zealand
64 9 3737599 x85392
p...@stat.auckland.ac.nz
http://www.stat.auckland.ac.nz/~paul/
______________________________________________
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel
--
Dr Paul Murrell
Department of Statistics
The University of Auckland
Private Bag 92019
Auckland
New Zealand
64 9 3737599 x85392
p...@stat.auckland.ac.nz
http://www.stat.auckland.ac.nz/~paul/
______________________________________________
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel
