Send xforms-development mailing list submissions to
address@hidden
To subscribe or unsubscribe via the World Wide Web, visit
https://lists.nongnu.org/mailman/listinfo/xforms-development
or, via email, send a message with subject or body 'help' to
address@hidden
You can reach the person managing the list at
address@hidden
When replying, please edit your Subject line so it is more specific
than "Re: Contents of xforms-development digest..."
Today's Topics:
1. Writing an oscilloscope screen with multiple moving signals
(Peter Rowat)
2. Re: Writing an oscilloscope screen with multiple moving
signals (Jens Thoms Toerring)
3. Re: Writing an oscilloscope screen with multiple moving
signals (Paul)
4. Re: Writing an oscilloscope screen with multiple moving
signals (Peter Rowat)
----------------------------------------------------------------------
Message: 1
Date: Fri, 27 Nov 2015 13:41:35 -0800
From: Peter Rowat <address@hidden>
To: address@hidden, Development with and of XForms
<address@hidden>
Subject: [XForms] Writing an oscilloscope screen with multiple moving
signals
Message-ID: <address@hidden>
Content-Type: text/plain; charset="utf-8"
I?m trying to get started on re-writing a system I had written in SunView back
in the 1990s. The heart of it is a display of multiple signals moving across
the screen, like an oscilloscope. In XForms, should I use a free object as in
the ?freedraw? demo, or should I start with the ?XYplot? demo. I need to use a
single ?box? as the signal amplitudes and the signal positions need to be
modifiable interactively, as the user sees how their system (typically a
dynamical system) is functioning. The signals can overlap. I?ve been looking
at several demos and it isn?t yet clear to me the appropriate way to proceed.
Any suggestions?
Peter Rowat
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://lists.nongnu.org/archive/html/xforms-development/attachments/20151127/076b2c68/attachment.html>
------------------------------
Message: 2
Date: Fri, 27 Nov 2015 23:22:59 +0100
From: Jens Thoms Toerring <address@hidden>
To: Peter Rowat <address@hidden>,
address@hidden
Subject: Re: [XForms] Writing an oscilloscope screen with multiple
moving signals
Message-ID: <address@hidden>
Content-Type: text/plain; charset=utf-8
Hi Peter,
On Fri, Nov 27, 2015 at 01:41:35PM -0800, Peter Rowat wrote:
I?m trying to get started on re-writing a system I had written in SunView
back in the 1990s. The heart of it is a display of multiple signals moving
across the screen, like an oscilloscope. In XForms, should I use a free
object as in the ?freedraw? demo, or should I start with the ?XYplot? demo.
I need to use a single ?box? as the signal amplitudes and the signal
positions need to be modifiable interactively, as the user sees how their
system (typically a dynamical system) is functioning. The signals can
overlap. I?ve been looking at several demos and it isn?t yet clear to me the
appropriate way to proceed.
It's a bit difficult to make suggestion not knowing how complex
your stuff is going to be. So let me just point out an alternative:
using a canvas. There are pro's and con's, of course. A drawback
is t it's a bit harder since you'll do your drawing using Xlib
functions and gettings started can be a bit time consuming. The
advantage is that you have complete control over everything that
happens, what's drawn where, when and how. You can request to
get all the raw XEvents for the canvas, so you basically react in
whatever way you want to them without them getting pre-digested
before they arrive. I used that approach with my fsc2 program that
draws data received from from all kinds of devives used in experi-
ments, either as several curves or a color coded area for data de-
pending on two experimental parameters. I've assigned mouse events
(with different buttons pressed down) for zooming, moving things
around, measuring distances etc. Took some time to get it to work
exactly as I wanted it to, but never looked bad - everything else
would've been too limited for my purposes. Basically, a canvas can
be seen as the nearest you can get to a plain X window whose con-
tent you completely manage yourself without intervention (but also
without moch help;-) from XForms.
Best regards, Jens