angle between two points

C
double angle = atan2(y2 - y1, x2 - x1) * 180 / PI;".PVector v1 = new PVector(10, 20);
PVector v2 = new PVector(60, 80); 
float a = PVector.angleBetween(v1, v2);
println(degrees(a));  // Prints "10.304827"

Source

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