comp.lang.idl-pvwave archive: archive » Re: Huge Maps & a device for faking a large window

Home » Public Forums » archive » Re: Huge Maps & a device for faking a large window

Show: Today's Messages :: Show Polls :: Message Navigator
E-mail to friend

Re: Huge Maps & a device for faking a large window [message #38839 is a reply to message #38837]

Wed, 31 March 2004 13:09

Michael Wallace
Messages: 409
Registered: December 2003

Senior Member

Here's a trick I've used before on *nix. If you're on Windows, you can
stop reading right here. There's a program called Xvfb which emulates a
dumb framebuffer using virtual memory. If it's not already installed on
your machine, there are plenty of places across the internet where you
can download it.

Once you have Xvfb, you can create a framebuffer with any dimension or
color depth you want. Then, make your IDL code use this new display
instead your actual X window session. IDL thinks that there is a valid
display available, however you do not see a thing. You can then create
a super-huge IDL window and do what you need to do with your map.
However, I don't know how Xvfb manages memory or how efficient it is.
This might not be a viable solution, but I don't know since I've never
used it in this way.

Even if this doesn't work for you, there are some good uses of the "Xvfb
trick," especially for automation. There have been times I wanted to
automate a task, but the program insisted on having a display even
though it didn't really need one. There have been other times when I've
wanted to automate programs that used the 'X' device. Instead of
changing code around to use the Z buffer and remove all of the
references to windows devices, I could just create a virtual framebuffer
and send all IDL graphical output to it. Now I can run those programs
even if no "real" display is available without changing a line of code.
I have a server that doesn't even have a monitor attached and I can
run graphical IDL code with no problem (assuming that there doesn't need
to be any graphical interaction with the program).

-Mike

Report message to a moderator

[Message index]

		Re: Huge Maps & a device for faking a large window By: Jack Saba on Thu, 01 April 2004 05:55
		Re: Huge Maps & a device for faking a large window By: JD Smith on Wed, 31 March 2004 15:38
		Re: Huge Maps & a device for faking a large window By: Liam Gumley on Wed, 31 March 2004 13:59
		Re: Huge Maps & a device for faking a large window By: Michael Wallace on Wed, 31 March 2004 13:09
		Re: Huge Maps & a device for faking a large window By: btt on Wed, 31 March 2004 12:46
		Re: Huge Maps & a device for faking a large window By: dmarino on Thu, 01 April 2004 13:13

Previous Topic:	Need help with value_locate and interpolation
Next Topic:	Re: How do I save parameters for next run?

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Mon Dec 01 13:07:41 PST 2025

Total time taken to generate the page: 0.96420 seconds