ok so, afaict iced currently only supports basic quad rendering, and image (raster and vector) rendering through the Renderer trait. the quads, intended for widgets like buttons, include ability to draw:
- a rectangle within some bounds.
- a single border with a single color and width, but the ability to change the border radius of each corner individually.
- a single shadow with an offset, single color, and a blur radius.
- a background within the bounds of either the rectangle, or if there is a border, within that (including any rounded corners).
- the background may be a single color or a linear gradient.
in terms of potential improvements to this rendering feature set i would probably mention (and please lmk if there is something important that i have missed):
- shadow-related:
- multiple shadows.
- inner shadows.
- shadow spread.
- shadow color being replaced with backgrounds (for gradient, and other background features).
- spread:
- spreads should have the ability to be based on scale reference, or distance from object path shape.
- backgrounds:
- further gradient types (radial, etc.).
- background image (tiled, scale, etc.).
- multiple backgrounds? (as backgrounds can be transparent and stack on each other).
- borders:
- different border widths, styles, and color depending on side (top, right, bottom, left).
- color option based on background like shadows.
- more border types (dashed, dotted, etc.).
- border image (with slice, fill, width, outset, and repeat-x/y options (stretch, repeat, round, space)).
- multiple borders:
- this one is a little messy, i think the only real use for this one is if you want to define an interesting border shape with border-image, and then add a basic border (solid, dashed, etc.) following the path of the image border shape. so basically at most there are two ‘borders’. following a border-image path would also be incompatible with any defined border-radius on the basic border. i guess you could technically potentially also like to have two different basic borders on top of each other? as in, a solid base, and a dashed overlay border, something like that.
- other:
- perspective warp for base quad, and for shadows, independently from the parent quad.
i’m guessing implementing these would require (breaking?) changes to the Renderer api, and therefore a bunch of new shader code, changes in wgpu and tiny_skia crates. also changes to the Border, Shadow, Background, Quad types, maybe a new ImageBorder type, Warp type. as well as of course actually editing the widget style catalogs to allow these options to be changed.
now my questions would be:
- is my understanding generally correct?
- would this level of styling even (eventually) be considered ‘in scope’ for the library?
i would also like to say i am of course interested in tackling these rendering features eventually, probably both once the iced api has become more stable, and i can prioritize it. i’m mostly just putting this here for discussion and reference atm.