Anglepic

[Qrrbrbirlbel]

Fixes #1363

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[muzimuzhi]

Instead of removing, how about rewrite it to

    The three points \meta{A}, \meta{B}, and \meta{C} can be either the names
    of nodes or coordinates, or direct coordinates like ``|(1,1)|''.

to document the extended syntax.

[Qrrbrbirlbel]

Sure, but it needs to be ``|1,1|'' then because the () are inserted by the pic's setup code. So pic […] {angle = {A--1,1--B.south west}} or pic […] {angle = A--{1,1}--B.south west} would be valid syntax.

[muzimuzhi]

You're right.

Then this syntax seems a bit more strange. Is a key-value interface needed here as well?

[Qrrbrbirlbel]

I wouldn't mind one. I always put the coordinates in the wrong order anyway. :D
But is it so strange? Sure, in most cases, the () are used to indicate something is a coordinate (and baseline et al uses it to decide between a value and a coordinate).
But there are also many that don't use the ():

• the technically deprecated (intersection of A--B and C--D) syntax where additional parentheses are missing (it even has the --)
• (A |- B) (and not ((A) |- (B)) = ({(A)} |- {(B)})) as well as
• below = of A.

They would all also allow 1, 1, the latter only with {}, of course.

---

We can check for -- – twice even – and use the old syntax (both for backwards compatibility and for the simple syntax), otherwise use start direction = (A), center = {(1, 1)}, end direction = (B.south west). I'd would even be as fancy as allowing start direction = (A), center = {(1, 1)}, delta angle=60. (But that can give weird results with xyz coordinate systems whose axes don't align with the canvas coordinate system. The arc/circle path operators solve this by choosing one or the other by looking whether the radii have a unit.)

The advantage of a key-value interface would be that it allows to set, say, a center coordinate for multiple angles.