Adds LineCanvas

[tznind]

Fixes #_____ - Adds new class for drawing connected lines in arbitrary configurations

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[BDisp]

@tznind how about to do the same feature for double lines and for rounded corners, single and double lines?

[tznind]

@tznind how about to do the same feature for double lines and for rounded corners, single and double lines?

Should be pretty easy to add a setting for rounded corners on the class.

It already supports double lines and mixing and matching single and double lines.

[BDisp]

Should be pretty easy to add a setting for rounded corners on the class.

It already supports double lines and mixing and matching single and double lines.

Great. The Border already use it, maybe you can use the same glyph's.

[tig]

💘

[tig]

Why StraightLineCanvas? Why not just LineCanvas? I can't imagine (probably because I'm dum) anything but straight lines in a TUI.

[tznind]

Why _Straight_LineCanvas? Why not just LineCanvas? I can't imagine (probably because I'm dum) anything but straight lines in a TUI.

Hmn its not great is it...

I was trying to articulate that it only supports Horizontal or Vertical lines (i.e. not diagonal). By contrast the PathAnnotation in the GraphView supports diagonal lines (although it just uses dots).

I think you are right though and we can probably just go with LineCanvas and in the AddLine xmldoc we can emphasise that its horizontal/vertical rather than PointA to PointB. And who knows maybe down the line we do add support for other line types e.g.

And who knows maybe down the line we do add support for other line types e.g. with braille:

[tznind]

I've marked this ready.

There is room for improvement later on e.g. when making a T that goes from a double line down to a single line you can use  ╨ but the number of combinations gets big fast and it would need quite a bit of work to implement them all.

We can always go down that route later.

[BDisp]

We can always go down that route later.

You are right. I think for now you can force to all borders being single or double (vertical and horizontal). When you have time then you will have a lot of work 😃.
That why I didn't implementing rounded corner for double because it probably need to use others codes for double vertical and horizontal lines.

[tig]

Is this puppy ready?

[tig]

This is awesome.

One question @tznind - have you considered how ConsoleDriver.DrawFrame would be re-factored to use this?

[tznind]

This is awesome.

One question @tznind - have you considered how ConsoleDriver.DrawFrame would be re-factored to use this?

Thanks for review and merge.

I'll take a look into refactoring frame drawing, should cut down the code quite a bit but will have to be careful not to make mistakes and add good code coverage.

Currently would be something like the below. But could add helper methods to LineCanvas to make it less verbose.

var canvas = new LineCanvas();
canvas.AddLine(new Point(region.X + paddingLeft,fleft),fwidth,Orientation.Horizontal,borderStyle);
canvas.AddLine(new Point(ftop,fleft),fheight,Orientation.Vertical,borderStyle);
// TODO: Add lower left lines up and left

var bmp = canvas.GenerateImage(region);
for(int y=0;y< bmp.GetLength(0) ;y++)
for(int x=0;x< bmp.GetLength(1) ;x++)
{
	var rune = bmp[y,x];
	if(rune.HasValue)
	{
		AddRuneAt (region.X + x, region.Y + y, rune.Value);
	}
}