Support flags with shapes

[kittsville]

I would like to create flags with coloured shapes e.g. progress flag

This would involve coloured squares, triangles and circles which overlay the bars.

Related to #3

[kittsville]

I'll start by adding arrow support. How to implement this depends on what you consider the underlying logic to flag creation. Daniel Quasar describes the arrows as being "half sized stripes" so let's try halfing the width of any flag's bars then displacing the arrows relative to the flag's left corners e.g.

• A flag with one arrow (demisexual) aligns with the flag's corners with 45° lines meeting in the vertical middle
• A flag with two+ arrows (progress pride flag) has arrows spaced diagonally by half the width of the bars, themselves spaced by the height of the flag divided by the number of bars. This would be (1/4) * √3 * barHeight

[kittsville]

I just assumed equilateral triangles had an angle of 45°. How did I get to A Level maths and through a CS degree?

[kittsville]

Created a mockup but it wasn't appearing as expected because the progress pride flag has a ratio of 5:3. This is presumably because it was created with flags in mind, which are typically 5ft by 3ft. This raises the issue I was hoping to avoid until later that flags have many different ratios: #9

Perhaps allow the flag to specify a ratio and resize the canvas on rendering? Any procedural generation of flags would then need to check if the flag contains arrows and avoid narrow ratios such as 3:2. Alternatively we can switch to 5:3 as the default and kick #9 down the road to deal with at a future date.

[kittsville]

I'm going to choose the lazy option and switch to 5:3.