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function calculatePerpendicularIntersect(centerPosition, startPosition, endPosition) { | |
const { x: cX, y: cY } = centerPosition; | |
const { x: sX, y: sY } = startPosition; | |
const { x: eX, y: eY } = endPosition; | |
const slopeStart = (cX - sX) / (cY - sY); | |
const slopePerp = 1 / slopeStart; | |
const intersectX = (slopeStart * sX - slopePerp * eX + eY - sY) / (slopeStart - slopePerp); | |
const intersectY = (intersectX - sX) * slopeStart + sY; | |
return { | |
x: intersectX, | |
y: intersectY | |
}; | |
} | |
function calculateControlPoint(centerPosition, startPosition, endPosition, perc) { | |
const perpIntersect = calculatePerpendicularIntersect(centerPosition, startPosition, endPosition); | |
return { | |
x: startPosition.x + (perpIntersect.x - startPosition.x) * perc, | |
y: startPosition.y + (perpIntersect.y - startPosition.y) * perc | |
} | |
} | |
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