[Squeakland] Pen Trails and Sensors

[Ned Konz]

On Friday 04 July 2003 11:15 am, Alan Kay wrote:
> >Some context for the rest of the list: unless the Squeakland image
> > has a fix that isn't in the Squeak 3.5 image, the turtle trails
> > aren't visible in the color:sees: test.
>
> That's odd and interesting -- they used to be, and should be -- for
> just some of the reasons that Jeff needed them. There are many
> wonderful things that can be done if the color sensing can see the
> turtle trails. Any idea of how this got lost? Can Scott Wallace
> easily put this back in?

I just posted a fix to the squeak-dev list that adds a per-Project 
preference for this (seeing the turtle trails in #color:sees: and 
#touchesColor:)

But there's two unresolved questions:

1. The turtle trails form is 8 bits. This means that the colorUnder: 
test may not work right when you're using a deeper Display depth. One 
possibility here (that will waste some memory) would be to make the 
turtle trails form as deep as the display. What should we do? Perhaps 
the deeper form should only be used when the preference is set?

2. Should turtle trails also be visible to the #colorUnder test?

-- 
Ned Konz
http://bike-nomad.com
GPG key ID: BEEA7EFE