B4J Question B4XCanvas: why lines are cut ?

[peacemaker]

Hi, All

Trying to use B4XCanvas for the first time.
Trying to join red point by drawing the yellow lines.
B4XCanvas is tied to the container placed over the image, but strange that the area where lines are visible - is limited sometimes, when app window is maximized:

Spoiler: Screenshots

Fullscreen:

Dimensions of the lines container is changed together with dimensions of the imageview.
Lines like placed into a box when app window is big.
What is wrong ?

 

[Cableguy]

If I understand correctly, the dots are not place onto the canvas, right?
I am guessing the coordinates scheme changes with the re-dimensioning of the image. Try to first place the dots on the same canvas plane, and once that works with the zoom, then connecting the dots will be a breeze.

 

[peacemaker]

place the dots on the same canvas plane

It's not so simple as just say...

It's Erel's code of ZoomImageView with several containers.
Some for dragging, some for zooming. One of them contains the ImageView.
I added the container for dots and cursor, and mouse events...

And now added the container for drawing lines that must be ... over the ImageView, transparent for mouse clicks...
It cannot have the same container with the Imageview - drawn lines are ... not visible under image

Why all is OK while container is small sized ?

 

[Cableguy]

Why all is OK while container is small sized ?

I can almost bet that if you zoom-out a bit more, the lines will be longer than needed be

 

[peacemaker]

Some edge variant when the app window is big, but not fullscreen:

Spoiler: Screenshot

 

[peacemaker]

will be longer than needed be

No, when small window - all is fully OK as expected.

 

[peacemaker]

Zoomed:

Spoiler: Screenshot:

 

[peacemaker]

Hmm, if to set many higher:

    #MainFormWidth: 1600
    #MainFormHeight: 1200

it gots OK with big zoom...

 

[peacemaker]

Solved: B4XCanvas must also be ... _Resized, when class' root container is _Resized.

Public Sub Base_Resize (Width As Double, Height As Double)
    pnl.SetLayoutAnimated(0, 0, 0, Width, Height)
    Reset
    canvas.Resize(Width, Height)
End Sub