Canvas size, bounds, and scrolling

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1

I will be drawing some stuff to a canvas and what I will be drawing will be too large for the actual screen space that the canvas with occupy. It is not reasonable to scale the drawing to fit due to the nature of the content. I want to know how these three things interelate (the documentation does not seem to say):

The canvas has some “size” (returned by its size() method. Is this size “fixed” for the life of the canvas or can it be grown/shrunk somehow.

The draw() method in the Program trait gets passed a bounds argument, a Rectangle struct. What does this represent? The canvas’s size or something else?

When creating a Frame, a size of passed to Frame’s new function. What are the limitations of this argument? Can I just specify something totally arbitarily large?

What happens if something is drawn “out of bounds” (outside of the Frame’s boundries)?

(Also how does a scrollable deal with a canvas? Or does it?)

In the original Tk implementation, using Tk’s canvas, it was possible to draw anywhere, including outside of the visible portion of the canvas. It was then possible to get an overall bounding box of everything that was drawn and that in turn can be used to set the canvas’s “scroll region”, which in turn would control scrollbars, allowing scrolling (both directions). I’m wondering, is it possible to do something similar with iced?

2

OK, first draft sort of works sorta. No horizontal scroll bar?

3

There’s a scrollable example.

Alternatively implement scrolling directly in your canvas, like in the game_of_life example

I encourage you to go through each of the examples to get more acquainted with the library. Just clone iced locally and run them one by one at least once.

4

OK, but is it possible to have both a vertical AND horizontal scrollbar? My application needs both.

5

You clearly haven’t gone through the links I’ve shared but expect me to keep answering questions one by one.

If you’re not comfortable with some level of self-study here, iced likely won’t be a good fit for you.

I’m sorry to put it so bluntly but it’s either that or to continue enabling your behavior which is not an outcome I desire.