simplesi
Posts: 2327
Joined: Fri Feb 24, 2012 6:19 pm
Location: Euxton, Lancashire, UK

Progress on the 3 main Scratch issues

Fri Sep 28, 2012 9:49 am

I was just wondering if anyone has made any progress on the 3 main bugs (variable display issue, jpg loading and keyboard stickyness)

Or if not, if anyone is actively working on any of these issues, would they mind putting their hand up to indicate which issue they are working on:)

Ta

Simon
Seeking help with Scratch and I/O stuff for Primary age children
http://cymplecy.wordpress.com/ @cymplecy on twitter

proxima
Posts: 30
Joined: Tue Sep 18, 2012 3:16 pm

Re: Progress on the 3 main Scratch issues

Sat Sep 29, 2012 10:54 am

Likewise, I'm interested to hear of any progress with these 3 problems, and I have offered to try and help, time permitting.

I am a C/C++ programmer by day, but I have no specific knowledge of either Scratch under the hood, or the VM it runs on (Squeak?). In another thread, I think 'ked' offered to give us a few pointers to get up and running with Scratch and Squeak from source trees - at that point, I will be happy to spend some time seeing if I can get up to speed enough to provide any help.

I'd be happy to try and look at the 'sticky keys' one, as that may be the best one for a "Scratch and Squeak" newcomer to look at, and would be my personal favourite one to get fixed, too.

ked
Posts: 42
Joined: Thu Aug 04, 2011 9:18 am

Re: Progress on the 3 main Scratch issues

Sat Sep 29, 2012 11:34 pm

There's three or four people working on it, including me. All the work is being done voluntarily or in spare time and unfortunately most people are already very busy. Performance is a complex issue and high priority. It takes time to isolate the issues and identify areas that can be customised for running on the RPi.

Progress: a program has been written and still being tweaked (almost done) to help ARM coder/s run isolated Squeak VM code with a view to ARM specific optimisations. At the same time Scratch/Squeak code is being examined to see if it can be streamlined for the graphics modes supported by the RPi. A combined X/FrameBuffer Squeak VM driver is being considered and work will begin on that soon. I think I've identified the reason for the jpg bug but not the cause. I will take another look at that in the next few days.

I'm not familiar with the sticky-keys problem and have not experienced it on the RPi or any other platform. Does the problem still occur on the latest Wheezy?

I appreciate the offer of help and had already begun writing condensed notes and tips to help anyone interested get set up for debugging. I'll get at least some of these notes posted in the next day or two as soon as the current work is completed. Apart from tips based on how I have things set-up, all the info and code you need can already be found on the web. The VM source code is available from the Raspbian repo's. The Scratch "source" package can be got from the Scratch Wiki site [1]. There's a wealth of info about Squeak from the main site [2] and even a free book to introduce you to Squeak [3]. Note though that the version of Squeak on which Scratch runs is somewhat older that the latest Squeak. It's still a very capable Squeak albeit without all the bells & whistles of the newer versions (some, including me, enjoy it regardless).

[1] http://wiki.scratch.mit.edu/wiki/Source_code
[2] http://www.squeak.org
[3] http://www.squeakbyexample.org/

proxima
Posts: 30
Joined: Tue Sep 18, 2012 3:16 pm

Re: Progress on the 3 main Scratch issues

Sun Sep 30, 2012 6:51 am

ked wrote:I'm not familiar with the sticky-keys problem and have not experienced it on the RPi or any other platform. Does the problem still occur on the latest Wheezy?
I'll find out and let you know as soon as possible, hopefully later today.

Thanks for your reply.

Regards,
Tom

proxima
Posts: 30
Joined: Tue Sep 18, 2012 3:16 pm

Re: Progress on the 3 main Scratch issues

Sun Sep 30, 2012 9:39 am

Yes, the problem still occurs in Scratch running on the latest (2012-09-18) distribution.

To clarify, the problem only occurs in Scratch - it doesn't seem to be a problem in other applications running under the Pi. Also, it doesn't occur when running Scratch under Windows (haven't been able to test other platforms).

A fuller description of the problem, including a sample script written by simplesi, is here http://www.raspberrypi.org/phpBB3/viewt ... 77&t=17840

I'm happy to try and look into the problem myself, if it's the sort of thing a 'newbie' might be able to help with - a bit of a learning curve ahead on the Squeak/Scratch front I imagine though.

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