On 2 April 2016 at 20:59, stepharo <stepharo@free.fr> wrote:
Le 2/4/16 17:31, Aliaksei Syrel a écrit :
You don't want to draw a shape, you configure it. Shape can not be drawn, it is not an AthensPath.
cell shape: (BlShape new path: BlCirclePath new; strokePaint: (BlStrokePaint new paint: Color blue; width: 1)). cell extent: 50@50.
But this is not what I want! As I mentioned in a mail that was sent but never arrived. I want a square and this is why I did
BlCell>>initialize super initialize. self shape: (BlShape new fillPaint: (BlColorPaint new color: (Color yellow)); path: BlRectanglePath new); extent: self extent
then I want to draw something extra this is why I overrode drawOnAthensCanvas: aCanvas
Now I stop but I find bloc too complex.
Sorry but I cannot lose time like that and just get frustrated at the end. I will use the athens canvas directly and stay in morph for now.
I think there's a bit of misconception. In Athens, shape representing any area you wanna fill with paint. Period. It can be of any complexity, self-intersecting yadda yadda.. the main point is that it defines a region(s), that going to be filled with chosen paint during draw operation.
From perspective of morphs, as UI elements, most of them require some shape(s) to represent themselves on the screen. But there are morphs, that while still taking part in UI, don't need any shapes since they never drawn on the screen. Another point is that nowhere said that morph can be represented by a one and only one shape period. Because as in your case, you want to, say, draw rectangle with paint A, and circle with paint B, then you basically need two different shapes (overlapping or not - not really matters) to represent morph on the screen.
So, the first point in misconception comes from 'self shape:'.. It is wrong from that perspective, because it is all fine, when morph using only single shape to represent itself.. but when you need multiple shapes, you are in trouble. It at least misleading, because provoking you to think that there can be only one. Then you need to invent a 'composite shape' that basically a collection of shapes for a single morph, that will represent it on the screen. A tangent to that, is that since most of morphs has mostly static geometry/topology and changing it very rarely and much less often comparing to drawing same shape(s) over and over again, it is right thing to define and initialize shape(s) and reuse them later in #draw method. Since you don't change shape(s), you don't have to generate new object(s).
From that perspective, this is nice, resource saving, approach. But let us not forget, that this is just a 'statistical observation' and hence good to be a default setup. But it should not dictate you the rule(s). You should still be able to define shape(s) on the fly or change it on the fly, dynamically.
Another problematic is that you may want to use different shapes for a) painting morph on screen b) defining geometry of the morph for UI interactions. As an example, let say, you want a rectangle with circle in centre on the screen, but also want morph to react on mouse over/clicks only if mouse cursor is inside a circle, but not when it's over an area covered by rectangle. What it means, that from UI perspective, you want from morph to define its shape, lets call it 'UI interaction shape'.. and from that perspective 'self shape:' is a good choice. But as example says, it has nothing to do with 'drawing shape(s)', which may or may not coincide with shape you using for UI interaction(s). Because it defines an area, where UI stuff could happen. And indeed, you really need one, and only one. You don't need multiple shapes there, since it serves to answer a simple question: 'are my mouse in interesting region or not'?. Like in your case, when you having box with circle inside , which is two shapes, but only one shape that can define an interesting region, it could be: - intersection of - union - subtraction And that could be completely different from shape(s) you may need to draw it on the screen. Stef
On Apr 2, 2016 4:57 PM, "stepharo" < <stepharo@free.fr>stepharo@free.fr> wrote:
Hi
I want a square morph with a circle or a line at 45 degree inside Now I do not get it.
I thought that I needed to specialize drawOnAthensCanvas: so I did
BlCell >> drawOnAthensCanvas: aCanvas
super drawOnAthensCanvas: aCanvas. aCanvas drawShape: (BlShape new strokePaint: (BlStrokePaint new paint: (BlColorPaint new color: (Color blue)); width: 15); path: BlCirclePath new).
Now I do not know how I can specify a shape size
So I will use another API than drawShape:
Stef
-- Best regards, Igor Stasenko.