On 24-04-2016, at 1:31 PM, David T. Lewis lewis@mail.msen.com wrote:

That's really quite impressive!

I think it shows just how much can be done to improve software with clever people and decent engineering and determination.

The Pi/Scratch work has involved - lots of rewriting Squeak code to be more effective - lots of rewriting poorly chosen algorithms in the Scratch code - porting forward to the 4.5 system so we could use the stack VM - much detective work to dig out what used to happen so the new system can be made to do the same where needed (for example a current problem stems from a tiny change in how Warpblt reports a rotation center) - writing a Cog for ARM (which obviously relies immensely on Eliot’s work of many years) - a new ARM specific bitblt core - and not shown in those videos a new Pi GPIO pin driver to make it easy to make LEDs explode, buzzers to shriek, motors rev to catastrophe and nuclear power plants to melt down

Lots of people on this list have contributed advice, bug fixes and improvements over the years. Thank you all - not just from me, but from the approximately 2.5 million kids that apparently regularly use Scratch on Pis in places from New York to York to Beirut to Euxton to rural India, China and Africa.

tim -- tim Rowledge; tim@rowledge.org; http://www.rowledge.org/tim Useful random insult:- Immune from any serious head injury.