62 lines
1.1 KiB
Go
62 lines
1.1 KiB
Go
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package mx
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//import "fmt"
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// The type represents mathematical equation of line and line itself.
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type LineExpr struct {
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K, C, X Float
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Vertical bool
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}
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// Returns the line itself. Made to implement the Liner interface.
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func (l LineExpr) GetLineExpr() LineExpr {
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return l
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}
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func (e LineExpr) GetContainedPoints(pts Vectors) Vectors {
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ret := make(Vectors, 0, len(pts))
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for _, pt := range pts {
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if e.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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func (l LineExpr) ContainsPoint(p Vector) bool {
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buf := LineExpr{0, p.Y, 0, false}
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pc, ok := DoLinersCross(l, buf)
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if !ok {
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return false
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}
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//Println("points:", l, p, pc)
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return Neq(pc.Point.X, p.X) && Neq(pc.Point.Y, p.Y)
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}
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func (l1 LineExpr) Crosses(l2 LineExpr) (Vector, bool) {
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var x, y Float
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if AreLinersParallel(l1, l2) {
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return ZV, false
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}
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switch {
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case l1.Vertical :
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x = l1.X
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y = l2.K*x + l2.C
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//Println("l1-vert:", x, y)
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case l2.Vertical :
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x = l2.X
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y = l1.K*x + l1.C
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//Println("l2-vert:", x, y)
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default:
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x = (l1.C - l2.C) / (l2.K - l1.K)
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y = l1.K*x + l1.C
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}
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//Println("in:", x, y)
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return Vector{x, y}, true
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}
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