svg

/*
Package svg is a minimalist and extensible SVG generation library for Gno.

It is the B+ tree successor to [gno.land/p/moul/svg/v1] (whose canvas styles are
backed by an AVL tree): a bump to v2 because the backing data structure used for
the canvas style map — and thus the on-chain storage layout — changed from
[gno.land/p/nt/avl/v0] to [gno.land/p/nt/bptree/v0]. The exported API is
otherwise identical to v1.

A B+ tree packs many entries per persisted node, so a stored style entry costs
less storage than the AVL backing (and inserts spend materially less gas).
Prefer v2 when the canvas is part of persisted realm state.

Two behavioral caveats inherited from the in-place-mutating B+ tree backing:

  - do NOT call AddStyle from inside a Canvas.String/Render iteration — the AVL
    backing tolerated mutation during iteration, the B+ tree one does not;
  - do NOT copy a non-zero Canvas by value once styles have been added — the
    copies would share live B+ tree nodes (v1's AVL copies were independent).

It provides a structured way to create and compose SVG elements such as rectangles, circles, text, paths, and more. The package is designed to be modular and developer-friendly, enabling optional attributes and method chaining for ease of use.

Each SVG element embeds a BaseAttrs struct, which supports common SVG attributes like `id`, `class`, `style`, `fill`, `stroke`, and `transform`.

Canvas objects represent the root SVG container and support global dimensions, viewBox configuration, embedded styles, and element composition.

Example:

	import "gno.land/p/moul/svg/v2"

	func Foo() string {
		canvas := svg.NewCanvas(200, 200).WithViewBox(0, 0, 200, 200)
		canvas.AddStyle(".my-rect", "stroke:black;stroke-width:2")
		canvas.Append(
			svg.NewRectangle(60, 40, 100, 50, "red").WithClass("my-rect"),
			svg.NewCircle(50, 80, 40, "blue"),
			&svg.Path{D: `M 10,30
			A 20,20 0,0,1 50,30
				A 20,20 0,0,1  90,30
				Q 90,60 50,90
				Q 10,60 10,30 z`, Fill: "magenta"},
			svg.NewText(20, 50, "Hello SVG", "black"),
		)
		mysvg := canvas.Base64()
	}
*/
package svg // import "gno.land/p/moul/svg/v2"