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It looks ok to me, except for the missing $] at the end of #drawOn:<br>
<br>
Cheers,<br>
<br>
On 7/11/2024 8:50 PM, Mark Volkmann via Cuis-dev wrote:
<blockquote
cite="mid:CAFfRWnVy-rROcSNB3nP3p652Pzy2t8TwZcpa_JwbWLXeQfp3QA@mail.gmail.com"
type="cite">
<div dir="ltr">
<div dir="ltr">On Thu, Jul 11, 2024 at 5:51 PM Juan Vuletich
<<a moz-do-not-send="true" href="mailto:juan@cuis.st">juan@cuis.st</a>>
wrote:<br>
</div>
<div class="gmail_quote">
<blockquote class="gmail_quote" style="margin: 0px 0px 0px
0.8ex; border-left: 1px solid rgb(204, 204, 204);
padding-left: 1ex;">
<div bgcolor="#ffffff"> On 7/11/2024 4:39 PM, Mark Volkmann
via Cuis-dev wrote:
<blockquote type="cite">
<div dir="ltr">When creating a custom morph it's not
clear to me whether I should subclass PlacedMorph or
BoxedMorph.
<div><br>
</div>
<div>I see that PlacedMorph doesn't hold the size of
the morph, but BoxedMorph does. BoxedMorph has the
instance variable extent and the accessors
morphExtent and morphExtent:. I want to be able to
set the extent of my custom morph instances and
utilize that size information in my drawOn: method.</div>
<div><br>
<div>However, the drawOn: method in PlaceMorph uses
a VectorCanvas and BoxedMorph uses a HybridCanvas.
HybridCanvas doesn't have the
strokeWidth:color:fillColor:do: method and I want
to use that.</div>
<div><br>
</div>
<div>I could add my own extent instance variable to
my PlacedMorph subclass, but that feels wrong.</div>
<div><br>
</div>
<div>I need some advice on this.</div>
<div><br>
</div>
<div>
<div><span class="gmail_signature_prefix">-- </span><br>
<div dir="ltr" class="gmail_signature">
<div dir="ltr">
<div>
<div dir="ltr">
<div>
<div dir="ltr">
<div dir="ltr">
<div><font face="arial, helvetica,
sans-serif">R. Mark Volkmann</font></div>
<div><span style="font-size:
12.8px;"><font face="arial,
helvetica, sans-serif">Object
Computing, Inc.</font></span></div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</blockquote>
BoxedMorph are a Hierarchy for morphs that are rectangle
like, and that occupy an area that can be specified as a
Rectangle. This means that, besides being of rectangular
shape, sides are aligned with local coordinate axes.
Including rectangles with rounded corners and such. The
idea is that the 'extent' ivar is all that's needed to
establish our dimensions and shape.<br>
<br>
They are used, for example, for common widgets.<br>
<br>
If your morph is not in the shape of a rectangle, it is
better to make it a PlacedMorph. See `PlacedMorph
subclasses`, and play with instances of them in your
Morphic World to see some of the things that can be done.<br>
<br>
See #requiresVectorCanvas and #knowsOwnLocalBounds. You
can redefine #requiresVectorCanvas in a subclass of
BoxedMorph if desired. But see, in the other subclasses of
PlacedMorph, the kind of freedom you get when you can make
#knowsOwnLocalBounds answer false.<br>
<br>
Finally, you can add whatever instance variable you need
to any of your classes. You're the master. Why would
adding 'extent' to your own PlacedMorph feel wrong, if
that happens to be what you need / want? Don't be shy.
You're just playing.<br>
<br>
Happy explorations!</div>
</blockquote>
<div><br>
</div>
<div>Thanks Juan! I suppose the reason I thought that adding
an `extent` instance variable to my class was suspect is
that I would get that automatically if I subclass BoxedMorph
instead of PlacedMorph.</div>
<div><br>
</div>
<div>Here is my latest code that subclasses PlacedMorph and
does add an `extent` instance variable. I'm curious if
anyone sees anything suspect in this code.</div>
<div><br>
</div>
<div><font face="monospace">PlacedMorph subclass: #CanvasDemo<br>
instanceVariableNames: 'extent'<br>
classVariableNames: ''<br>
poolDictionaries: ''<br>
category: 'Volkmann'<br>
</font></div>
<div><font face="monospace"><br>
</font></div>
<div><font face="monospace">extent<br>
^ extent<br>
</font></div>
<div><font face="monospace"><br>
</font></div>
<div><font face="monospace">extent: aPoint<br>
extent := aPoint<br>
</font></div>
<div><font face="monospace"><br>
</font></div>
<div><font face="monospace">initialize<br>
super initialize.<br>
extent := 100 @ 100<br>
</font></div>
<div><font face="monospace"><br>
</font></div>
<div><font face="monospace">drawOn: aCanvas<br>
| x1 x2 y1 y2 |<br>
</font><span style="font-family: monospace;"> <span
class="gmail-Apple-converted-space"> </span></span><font
face="monospace">x1 := 0.<br>
</font><span style="font-family: monospace;"> <span
class="gmail-Apple-converted-space"> </span></span><font
face="monospace">y1 := 0.<br>
</font><span style="font-family: monospace;"> <span
class="gmail-Apple-converted-space"> </span></span><font
face="monospace">x2 := extent x.<br>
</font><span style="font-family: monospace;"> <span
class="gmail-Apple-converted-space"> </span></span><font
face="monospace">y2 := extent y.<br>
</font><span style="font-family: monospace;"> <span
class="gmail-Apple-converted-space"> </span></span><font
face="monospace">aCanvas strokeWidth: 10 color: Color red
fillColor: Color green do: [<br>
</font><span style="font-family: monospace;"> <span
class="gmail-Apple-converted-space"> </span></span><span
style="font-family: monospace;"> </span><span
class="gmail-Apple-converted-space" style="font-family:
monospace;"> </span><span style="font-family: monospace;">aCanvas</span></div>
<div><span style="font-family: monospace;"> </span><span
class="gmail-Apple-converted-space" style="font-family:
monospace;"> </span><span style="font-family: monospace;">
</span><span class="gmail-Apple-converted-space"
style="font-family: monospace;"> </span><span
style="font-family: monospace;"> </span><span
class="gmail-Apple-converted-space" style="font-family:
monospace;"> </span><span style="font-family: monospace;">moveTo:
x1 @ y1;</span></div>
<div><span style="font-family: monospace;"> </span><span
class="gmail-Apple-converted-space" style="font-family:
monospace;"> </span><span style="font-family: monospace;">
</span><span class="gmail-Apple-converted-space"
style="font-family: monospace;"> </span><span
style="font-family: monospace;"> </span><span
class="gmail-Apple-converted-space" style="font-family:
monospace;"> </span><font face="monospace">lineTo: x2 @
y2;<br>
</font><span style="font-family: monospace;"> </span><span
class="gmail-Apple-converted-space" style="font-family:
monospace;"> </span><span style="font-family: monospace;">
</span><span class="gmail-Apple-converted-space"
style="font-family: monospace;"> </span><span
style="font-family: monospace;"> </span><span
class="gmail-Apple-converted-space" style="font-family:
monospace;"> </span><font face="monospace">lineTo: x2 @
y1;<br>
</font><span style="font-family: monospace;"> </span><span
class="gmail-Apple-converted-space" style="font-family:
monospace;"> </span><span style="font-family: monospace;">
</span><span class="gmail-Apple-converted-space"
style="font-family: monospace;"> </span><span
style="font-family: monospace;"> </span><span
class="gmail-Apple-converted-space" style="font-family:
monospace;"> </span><font face="monospace">lineTo: x1 @
y1;<br>
</font><span style="font-family: monospace;"> </span><span
class="gmail-Apple-converted-space" style="font-family:
monospace;"> </span><span style="font-family: monospace;">
</span><span class="gmail-Apple-converted-space"
style="font-family: monospace;"> </span><span
style="font-family: monospace;"> </span><span
class="gmail-Apple-converted-space" style="font-family:
monospace;"> </span><font face="monospace">lineTo: x1 @
y2;<br>
</font><span style="font-family: monospace;"> </span><span
class="gmail-Apple-converted-space" style="font-family:
monospace;"> </span><span style="font-family: monospace;">
</span><span class="gmail-Apple-converted-space"
style="font-family: monospace;"> </span><span
style="font-family: monospace;"> </span><span
class="gmail-Apple-converted-space" style="font-family:
monospace;"> </span><font face="monospace">lineTo: x2 @ y2<br>
<br>
</font></div>
<div><font face="arial, sans-serif">Here's an example of using
this class:</font></div>
<div><font face="monospace"><br>
</font></div>
<div><font face="monospace">cd := CanvasDemo new extent:
300@400.<br>
cd openInHand.</font></div>
</div>
<div><br>
</div>
<span class="gmail_signature_prefix">-- </span><br>
<div dir="ltr" class="gmail_signature">
<div dir="ltr">
<div>
<div dir="ltr">
<div>
<div dir="ltr">
<div dir="ltr">
<div><font face="arial, helvetica, sans-serif">R.
Mark Volkmann</font></div>
<div><span style="font-size: 12.8px;"><font
face="arial, helvetica, sans-serif">Object
Computing, Inc.</font></span></div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</blockquote>
<br>
<br>
<pre class="moz-signature" cols="72">--
Juan Vuletich
cuis.st
github.com/jvuletich
researchgate.net/profile/Juan-Vuletich
independent.academia.edu/JuanVuletich
patents.justia.com/inventor/juan-manuel-vuletich
linkedin.com/in/juan-vuletich-75611b3
twitter.com/JuanVuletich</pre>
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