[Squeakland] scripted drawing as an object?

[Bert Freudenberg]

Am 25.05.2005 um 21:09 schrieb Randy Heiland:

> Hi Squeakers,
>
> In Etoys, can I make some drawing that was the result of a script  
> become an
> object?  For example, consider the simple circle-drawing script  
> (fwd by,
> turn by, pen down).  Can I somehow treat that resulting circle as  
> an object
> and thereby make copies of it, etc?  I realize that I could use  
> either the
> 'Grab Patch' or 'Lasso' in the Supplies to manually "select" the  
> circle,
> however that approach of course gives me more pixels than I really  
> want.

Hi Randy,

this is not quite possible out-of-the-box, as far as I know. However,  
nothing is impossible in Squeak ;-)

Here's what you can do:

1. Make a new playfield.
2. Place your drawing player in the playfield.
3. Let it draw.
4. Set the playfield's graphic to the drawn pen trails.
5. Make a new sketch.
6. assign the playfield's graphic to the sketch's graphic.
7. You're done :-)

Now that seems straight-forward, but unfortunately there is no  
"setGraphicFromTrails" tile that we need for step 4.  We'll need a  
bit of magic. Here is how to make that tile:
4a. Get a viewer on the playfield.
4b. From the "playfield" category, drag out the arrow tile for  
"playfields graphic", making a script.
4c. Rename the script to "setGraphicFromTrails".
4d. Switch the script to textual mode (click the square checkbox in  
the upper left of the script)
4e. Replace the text shown there:
=====================
setGraphicFromTrails
     self setGraphic: Form3
=====================
with the following (just copy and paste):
=====================
setGraphicFromTrails
self setGraphic: ((self costume instVarNamed: #turtleTrailsForm)
ifNotNilDo: [:f | f trimBordersOfColor: Color transparent])
=====================
Accept using Cmd-s (Alt-s on PC).
4f. Hide the script with the "o" button.
4f. In the playfield's scripts category you'll find your shiny new  
"setGraphicFromTrails" tile.

For step 6, you could make a skript for the sketch like this:

     Playfield setGraphicFromTrails
     Sketch's graphic <- Playfield's graphic

I think this might be a valuable feature to add generally - that is,  
making the pen trail's graphic available as a tile. Maybe for the  
next etoys version.

- Bert -