ios - How to calculate area of an organic shape? -

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i want know possible calculate area of organic shape. shape im trying calculate looks this:

imagine drawn cgpoints

is there special function this? im thinking maybe coreimage or quartz or maybe opengl.

if boundary path consists of straight line segments , not intersect can use following formula compute area of enclosed region (from https://en.wikipedia.org/wiki/polygon#area_and_centroid):

cgpoint points[n];   cgfloat area = 0; (int = 0; < n; i++) {     area += (points[i].x * points[(i+1) % n].y - points[(i+1) % n].x * points[i].y)/2.0; }

where points[0], ... , points[n-1] starting points of line segments in counter-clockwise order.

for more complicate path segments such bézier curves, can subdivide each segment small parts can approximated line segments.


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