Re: [CSSOM] Revisiting transforms and getBoundingClientRect()

On Fri, Sep 9, 2011 at 7:01 AM, Simon Fraser <smfr@me.com> wrote:

> Sure. With all these new point/quad methods, maybe we should bite the
> bullet and have a WebPoint class with x, y members. Then WebQuad can have 4
> WebPoints.
>
> The poorly-named ClientRect should become WebRect.
>

I don't think we should have "Web" prefixes on Web APIs. If we need a
prefix, maybe CSSRect.

> Having a variety of functions for the content, padding and margin rects
> seems like overkill; I would prefer one or two "bottleneck" quad mapping
> functions with helper methods to get the various boxes for a given element.
> >
> > I'm not quite sure what you mean. Can you suggest something?
>
> The basic pieces seem to be:
>
> 1. Get an element's padding, content, border and margin boxes relative to
> its own border-box, as rects.
> 2. Convert a rect to a quad.
> 3. Map arbitrary point from one element to another.
> 4. Map arbitrary quad from one element to another (mapping 4 points)
>
> We should make sure each of these steps is available to web developers,
> possibly with the addition of convenience wrappers.
>
> That suggests:
>
>  const CONTENT_BOX;
>  const PADDING_BOX;
>  const BORDER_BOX;
>  const MARGIN_BOX;
>  WebRectList element.localBoxes(boxType); // relative to border-box of
> first box.
>
> Quad to rect conversions:
>  WebQuad rect.toQuad();
>  WebRect quad.boundingRect();
>
> Would be nice to have a way to convert a WebRectList to a WebQuadList.
>
>  WebPoint element.mapPoint(WebPoint, [relativeTo])  // point is border-box
> relative on both ends.
>  WebQuad element.mapQuad(WebQuad, [relativeTo]) // quads are border-box
> relative on both eneds
>  WebQuadList element.mapQuads(WebQuadList, [relativeTo]) // ditto


That breakdown makes a lot of sense. I'd bikeshed a little over the syntax
for localBoxes() and boundingRect(). We should definitely use multiple
methods instead of a boxType parameter IMHO.

Rob
-- 
"If we claim to be without sin, we deceive ourselves and the truth is not in
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