gopatterns/pkg/pattern/point/absolute_point.go

package point

import (
	"git.wtrh.nl/wouter/gopatterns/pkg/position"
	"git.wtrh.nl/wouter/gopatterns/pkg/vector"
	"github.com/tdewolff/canvas"
)

// AbsolutePoint implements Point and defines an absolute position.
// All other points should eventually be relative to one or more absolute point(s).
type AbsolutePoint struct {
	id       ID
	position position.Position
	name     string
	draw     bool
	hide     bool
}

// Matrix calculates and returns the [canvas.Matrix] of a point.
func (a *AbsolutePoint) Matrix() canvas.Matrix {
	return canvas.Identity.Translate(a.position.Vector.Values()).Rotate(a.position.Rotation)
}

// ID returns the point ID.
func (a *AbsolutePoint) ID() ID {
	return a.id
}

// Name returns the name of a point.
func (a *AbsolutePoint) Name() string {
	return a.name
}

// Position calculates and returns the absolute [position.Position].
func (a *AbsolutePoint) Position() position.Position {
	return a.position
}

// Vector calculates and returns the absolute [vector.Vector].
func (a *AbsolutePoint) Vector() vector.Vector {
	return a.Position().Vector
}

// NewAbsolutePoint returns a new absolute point.
func NewAbsolutePoint(x, y, r float64, id ID) *AbsolutePoint {
	return &AbsolutePoint{
		position: position.Position{
			Vector: vector.Vector{
				X: x,
				Y: y,
			},
			Rotation: r,
		},
		id:   id,
		name: string(id),
	}
}

// Draw returns if the point should be drawn.
func (a *AbsolutePoint) Draw() bool {
	return a.draw
}

// SetDraw indicates that the point should be drawn.
func (a *AbsolutePoint) SetDraw() {
	a.draw = true
}

// UnsetDraw indicates that the point should not be drawn.
func (a *AbsolutePoint) UnsetDraw() {
	a.draw = true
}

// Hide returns if the point must remain hidden.
func (a *AbsolutePoint) Hide() bool {
	return a.hide
}

// SetHide indicates that the must be hidden.
func (a *AbsolutePoint) SetHide() {
	a.hide = true
}