[Squeakland] Pen Trails and Sensors

[Bert Freudenberg]

It works in playfields, not on the World itself. And it can be tricky  
to choose the right color because the trails are in 8 bit while the  
rest is in 16 or 32. Things evolve ;-)

I'll sent a fix for both issues to the Squeak-Dev list.

-- Bert

Am Freitag, 04.07.03 um 20:15 Uhr schrieb Alan Kay:

> Thanks Ned --
>
> At 8:27 AM -0700 7/4/03, Ned Konz wrote:
>> On Thursday 03 July 2003 07:20 pm, Jeff Longland wrote:
>>>  I've been using
>>>  penDown to create a pen trail behind the snake, but my major
>>>  problem is that the sensor on my object is unable to view the pen
>>>  trail.
>>
>> Welcome Jeff!
>>
>> 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?
>
> Cheers,
>
> Alan
>
>>
>> One possibility is to make the turtle trails visible to the
>> color:sees: test (and add a per-Project Preference for making them
>> visible). Is there any interest in this?
>>
>> Looking back in the Squeakland list, I see that Markus Denker recently
>> posted a link to a project that includes an enhancement that Markus
>> Gaelli wrote. This enhancement lets you make PolygonMorphs (like
>> lines and filled polygons) from your scripts. So instead of using the
>> penDown turtle features, you'd add points to a line that you were
>> constructing. That would be visible to the color:sees: test.
>>
>> I quote Markus D here:
>>
>> ----
>>>  I was talking to Markus Gaelli abaout his PolygonFactory
>>>  improvement, and then I realised that sending a Link
>>>  to the squeak.org bugfix-archive is not the right thing to
>>>  do on the squeakland mailinglist... that's something for
>>>  the squeak.org hackers.
>>>
>>>  So here's now a version that is actually usable:
>>>
>>>
>> http://squeakland.org/project.jsp?http://www.ira.uka.de/~marcus/ 
>> PolygonFactory.001.pr
>>>
>>>  This is a project with Markus's new Polygon-drawing tiles and a
>>>  very simple example.
>>>
>>>          Marcus
>>>
>>>  On Fri, May 09, 2003 at 09:51:03AM +0200, Marcus Denker wrote:
>>>  > On Thu, May 08, 2003 at 02:07:41PM -0800, Alan Kay wrote:
>>>  > > However, it's also pretty clear that a more appropriate
>>>  > > implementation would be to have them actually make an object of
>>>  > > some kind (a SketchMorph or a PolygonMorph) that works like any
>>>  > > other object. We will probably do something like this in a
>>>  > > future version of etoys.
>>>  >
>>>  > Hi,
>>>  >
>>>  > Markus Gaelli posted something like that to the squeak-dev list
>>>  > some days ago:
>>>  >
>>>  > http://swiki.gsug.org:8080/sqfixes/3240.html
>>>  >
>>>  > from preamble:
>>>  >
>>>  >  "Change Set:            PolygonFactory
>>>  >  Date:                   20 April 2003
>>>  >  Author:                 Markus Gaelli
>>>  >
>>>  >  Did you ever want to paint polygons out of the traces of your
>>>  > EToy-cars?
>>>  >
>>>  >  Now it's possible.
>>>  >  Just drop a polygon in the world, open a viewer on it, select
>>>  > the category 'Miscellaneous'.
>>>  >  Here you can select between two new options: -
>>>  > setVertexFromPositionOf: dot
>>>  >  With this one you can initialize your polygon to have only one
>>>  > point, that is the current position of the player (replace 'dot'
>>>  > with the tile of your player / car)
>>>  >  - addVertexFromPositionOf: dot
>>>  >  Use this one if you want to add a new point to your polygon,
>>>  > which is the current position of the player (again replace 'dot'
>>>  > with the tile of your player, probably somewhere after you just
>>>  > moved it a bit...)
>>
>> --
>> Ned Konz
>> http://bike-nomad.com
>> GPG key ID: BEEA7EFE
>>
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>
>
> -- 
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