55 lines
982 B
Go
55 lines
982 B
Go
package physics
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import (
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"fmt"
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"math"
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"git.kirsle.net/go/render"
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)
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// Vector holds floating point values on an X and Y coordinate.
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type Vector struct {
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X float64
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Y float64
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}
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// NewVector creates a Vector from X and Y values.
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func NewVector(x, y float64) Vector {
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return Vector{
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X: x,
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Y: y,
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}
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}
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// VectorFromPoint converts a render.Point into a vector.
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func VectorFromPoint(p render.Point) Vector {
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return Vector{
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X: float64(p.X),
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Y: float64(p.Y),
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}
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}
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// IsZero returns if the vector is zero.
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func (v Vector) IsZero() bool {
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return v.X == 0 && v.Y == 0
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}
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// Add to the vector.
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func (v *Vector) Add(other Vector) {
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v.X += other.X
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v.Y += other.Y
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}
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// ToPoint converts the vector into a render.Point with integer coordinates.
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func (v Vector) ToPoint() render.Point {
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return render.Point{
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X: int(math.Round(v.X)),
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Y: int(math.Round(v.Y)),
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}
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}
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// String encoding of the vector.
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func (v Vector) String() string {
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return fmt.Sprintf("%f,%f", v.X, v.Y)
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}
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