[GRASS-user] Xming as X server for winGRASS?

[Paul Kelly]

Hi Luigi,

On Fri, 7 Mar 2008, Luigi Ponti wrote:

>> http://grass.ibiblio.org/gdp/html_grass63/variables.html#png for some ideas 
>> on how to control it.
> If anybody has a pointer to a working example that would be great. While the 
> concept is clear, the practicalities are not as evident by reading recent 
> posts on the topic:
> http://www.nabble.com/why-d.vect.thematic-won%27t-run-on-WinGRASS---d.mon-problem-td15054987.html#a15054987

Don't be put off by the doubts expressed in that thread! It really is very 
simple and easy to use and works very well.

> Particularly, how do you tell the PNG driver where to start/stop direct 
> rendering to png file without d.mon?

Set the environment variable GRASS_RENDER_IMMEDIATE to TRUE. That seems to 
be missed out in that list. Here is a simple example that works at the 
Windows command prompt (seeing you mentioned Windows) using spearfish:

set GRASS_RENDER_IMMEDIATE=TRUE
set GRASS_TRUECOLOR=TRUE
set GRASS_PNGFILE=c:\output.png
d.rast elevation.dem
rem Next line is required so the calls to d.vect are overlaid on the raster
set GRASS_PNG_READ=TRUE
d.vect roads color=black
d.vect streams color=blue

Hopefully that will get you started.

Paul