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NorbertHartl

Morph relative positions

Next try. I may do something stupid but it appears that all morphs draw on the same coordinate system. Meaning that every Morph that will draw something at 0@0 will put it in the top left corner of the image displayed. I would expect that a morph that is positioned somewhere provides a canvas where 0@0 is relative to the position of the morph. If coordinates are absoulte how can I delegate work to sub components and having them calculate the offsets properly?

Norbert

Igor Stasenko

Re: Morph relative positions

On 20 September 2013 12:15, Norbert Hartl <[hidden email]> wrote:

Next try. I may do something stupid but it appears that all morphs draw on the same coordinate system. Meaning that every Morph that will draw something at 0@0 will put it in the top left corner of the image displayed. I would expect that a morph that is positioned somewhere provides a canvas where 0@0 is relative to the position of the morph. If coordinates are absoulte how can I delegate work to sub components and having them calculate the offsets properly?

Welcome to club.

To ease the pain, take a look at TransformMorph.

Norbert

--
Best regards,
Igor Stasenko.

NorbertHartl

Re: Morph relative positions

Am 20.09.2013 um 12:24 schrieb Igor Stasenko <[hidden email]>:

On 20 September 2013 12:15, Norbert Hartl <[hidden email]> wrote:

Next try. I may do something stupid but it appears that all morphs draw on the same coordinate system. Meaning that every Morph that will draw something at 0@0 will put it in the top left corner of the image displayed. I would expect that a morph that is positioned somewhere provides a canvas where 0@0 is relative to the position of the morph. If coordinates are absoulte how can I delegate work to sub components and having them calculate the offsets properly?

Welcome to club.

To ease the pain, take a look at TransformMorph.

Thanks. I look at it but it is still hard to achieve something simple.

Norbert

Norbert

--
Best regards,
Igor Stasenko.

NorbertHartl

Re: Morph relative positions

In reply to this post by Igor Stasenko

Am 20.09.2013 um 12:24 schrieb Igor Stasenko <[hidden email]>:

On 20 September 2013 12:15, Norbert Hartl <[hidden email]> wrote:

Next try. I may do something stupid but it appears that all morphs draw on the same coordinate system. Meaning that every Morph that will draw something at 0@0 will put it in the top left corner of the image displayed. I would expect that a morph that is positioned somewhere provides a canvas where 0@0 is relative to the position of the morph. If coordinates are absoulte how can I delegate work to sub components and having them calculate the offsets properly?

Welcome to club.

To ease the pain, take a look at TransformMorph.

I figured out how to do it. Basically it is exactly what I need: transform geo coordinates to screen coordinates. But then LineMorph does not seem to like a borderWidth below 1. It is a drag. I think I could burn several days on this crap. Better start doing something different.

Norbert

Markus Schlager-2

Re: Morph relative positions

In reply to this post by NorbertHartl

On Fri, 20 Sep 2013, Norbert Hartl wrote:

> Next try. I may do something stupid but it appears that all morphs draw
> on the same coordinate system. Meaning that every Morph that will draw
> something at 0@0 will put it in the top left corner of the image
> displayed. I would expect that a morph that is positioned somewhere
> provides a canvas where 0@0 is relative to the position of the morph. If
> coordinates are absoulte how can I delegate work to sub components and
> having them calculate the offsets properly?

I had this problem to while teaching pupils (grade 10) Smalltalk as their
first 'real' programming language. We were embedding EllipseMorphs into a
PasteUpMorph. Embedded morphs know their owner, hence

self owner position

might be the desired offset.

Markus

Markus Schlager-2

Re: Morph relative positions

I'd not expect though, that it should be necessary to add offsets by hand.
What is the advantage of having embedded objects use global coordinates?

Markus

Igor Stasenko

Re: Morph relative positions

On 20 September 2013 17:37, Markus Schlager <[hidden email]> wrote:

I'd not expect though, that it should be necessary to add offsets by hand. What is the advantage of having embedded objects use global coordinates?

Markus

i don't know.. i think people who could answer this question is not on this list.

i think it, as many other aspects of our heritage, a result of many years of building on top of
once simple and robust things,
and that build-on-top-without-rethinking process led us to what we have now:

once simple and robust solution, now buried under tons of layers, where some of them
trying to extend design, and some trying to fix its original issues..
and all of that instead of changing design to something more adequate and simpler.

--
Best regards,
Igor Stasenko.

Igor Stasenko

Re: Morph relative positions

On 20 September 2013 19:22, Igor Stasenko <[hidden email]> wrote:

On 20 September 2013 17:37, Markus Schlager <[hidden email]> wrote:

I'd not expect though, that it should be necessary to add offsets by hand. What is the advantage of having embedded objects use global coordinates?

Markus

i don't know.. i think people who could answer this question is not on this list.
i think it, as many other aspects of our heritage, a result of many years of building on top of
once simple and robust things,
and that build-on-top-without-rethinking process led us to what we have now:
once simple and robust solution, now buried under tons of layers, where some of them
trying to extend design, and some trying to fix its original issues..

... and some of them there is to duplicate already existing functionality. i guess because people
was unaware of its existence or because coding is much more fun than reading and learning code :)

and all of that instead of changing design to something more adequate and simpler.

--
Best regards,
Igor Stasenko.

--
Best regards,
Igor Stasenko.

Stéphane Ducasse

Re: Morph relative positions

In reply to this post by Markus Schlager-2

On Sep 20, 2013, at 5:37 PM, Markus Schlager <[hidden email]> wrote:

> I'd not expect though, that it should be necessary to add offsets by hand. What is the advantage of having embedded objects use global coordinates?

conceptually this is a bug.

>
> Markus
>

hilaire

Re: Morph relative positions

In reply to this post by NorbertHartl

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NorbertHartl

Re: Morph relative positions

In reply to this post by Igor Stasenko

Am 20.09.2013 um 12:24 schrieb Igor Stasenko <[hidden email]>:

On 20 September 2013 12:15, Norbert Hartl <[hidden email]> wrote:

Next try. I may do something stupid but it appears that all morphs draw on the same coordinate system. Meaning that every Morph that will draw something at 0@0 will put it in the top left corner of the image displayed. I would expect that a morph that is positioned somewhere provides a canvas where 0@0 is relative to the position of the morph. If coordinates are absoulte how can I delegate work to sub components and having them calculate the offsets properly?

Welcome to club.

To ease the pain, take a look at TransformMorph.

Thanks. I'm trying to understand TransformMorph but I don't really get it. I cannot see _how_ it is transforming stuff. For testing I have three morphs

MasterMorph

TransformMorph

TestMorph

In TransformMorph I use

MorphicTransform offset: 0 angle: 0 scale: 10.0.

When I implement #drawOn: in TestMorph and do

aCanvas

fillRectangle: (Rectangle origin: 10@10 extent: 10@10)

color: Color red.

the result looks good although I don't understand where the coordinates are translated. To me it appears that the way it goes is from Canvas to GrafPort and I didn't find the location where TransformMorph comes into play. I'm trying to figure that out because I cannot use Float coordinates in my transform morph. Doing in TestMorph>>#drawOn something like

aCanvas fillRectangle: (Rectangle origin: 0.9@0.9 extent: 1@1)

color: Color green.

I get two problems. Basically the Rectangle is truncated to Ints before the transform. Additionally in this particular case the rectangle is not displayed at all. For 0.89@.089 I can see it truncated at origin 0@0 but at 0.9@0.9 it just disappears. Same goes for 0.63 and other values.

And I don't know how to debug morphic because using breakpoints is too dangerous while it is in stepping mode.

thanks,

Norbert