33 lines
468 B
Go
33 lines
468 B
Go
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package mx
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// The type describes a simple
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// math circle.
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type Circle struct {
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Center Vector
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Radius Float
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}
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func (c Circle) ContainsPoint(
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pt Vector,
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) bool {
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d := c.Center.Sub(pt)
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dx, dy := d.XY()
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d2 := dx*dx + dy*dy
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r2 := c.Radius*c.Radius
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return r2 > d2
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}
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func (c Circle) GetContainedPoints(
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pts Vectors,
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) Vectors {
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ret := make(Vectors, 0, len(pts))
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for _, pt := range pts {
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if c.ContainsPoint(pt) {
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ret = append(ret, pt)
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}
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}
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return ret
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}
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