go-opengl-pixel/examples/community/ASharedJourney/supervisor/direction.go

package supervisor

import (
	"github.com/faiface/pixel"
	"github.com/faiface/pixel/examples/community/ASharedJourney/tiles"
)

//call motion
func Move() *PlayerDirections {
	newDir := new(PlayerDirections)
	newDir.Player1 = key()
	newDir.mirror()
	return newDir
}

//mirror motion of player 1 onto direction of player 2
func (dir *PlayerDirections) mirror() {
	dir.Player2.X = dir.Player1.X
	if dir.Player1.Y != 0 {
		dir.Player2.Y = dir.Player1.Y * (-1)
	}
}

//calculate next position based on direction
func (dir Direction) Next(currentPos pixel.Vec) pixel.Vec {
	currentPos.X += float64(dir.X * tiles.TileSize)
	currentPos.Y += float64(dir.Y * tiles.TileSize)
	//log.Printf("Calculated next position ", currentPos)
	return currentPos
}