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Re: Arc Adjustment proposal


On 2019-07-10 14:08, Brian wrote:
On 7/10/19 2:02 PM, Seth Hillbrand wrote:
Start-center-end is under constrained and requires the additional knowledge of which direction the arc is going.

On the contrary.  Start-center-end is fully constrained.  Arc
direction is implied and unambiguous.

Ah yes, you are right. We can assume a CW or CCW direction and swap start/end to match.

The only remaining concern would be robustness. You can create a start-center-end combination that is invalid, so we'd need to define a governing parameter.

The start-midpoint-end triplet can also be invalid but only if you assume the midpoint is exactly midway. The three-point conversion I listed previously allows the third point to exist anywhere on the arc and avoids this issue. We would use midpoint for convenience when writing the file but don't require it when reading.

Is there a good solution to this issue for the center point idea?


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