up3

server/block/cube/axis.go

@@ -0,0 +1,63 @@
+package cube
+
+import "github.com/go-gl/mathgl/mgl64"
+
+// Axis represents the axis that a block, such as a log, may be directed in.
+type Axis int
+
+const (
+	// Y represents the vertical Y axis.
+	Y Axis = iota
+	// Z represents the horizontal Z axis.
+	Z
+	// X represents the horizontal X axis.
+	X
+)
+
+// String converts an Axis into either x, y or z, depending on which axis it is.
+func (a Axis) String() string {
+	switch a {
+	case X:
+		return "x"
+	case Y:
+		return "y"
+	default:
+		return "z"
+	}
+}
+
+// RotateLeft rotates an Axis from X to Z or from Z to X.
+func (a Axis) RotateLeft() Axis {
+	switch a {
+	case X:
+		return Z
+	case Z:
+		return X
+	default:
+		return 0
+	}
+}
+
+// RotateRight rotates an Axis from X to Z or from Z to X.
+func (a Axis) RotateRight() Axis {
+	// No difference in rotating left or right for an Axis.
+	return a.RotateLeft()
+}
+
+// Vec3 returns a unit Vec3 of either (1, 0, 0), (0, 1, 0) or (0, 0, 1),
+// depending on the Axis.
+func (a Axis) Vec3() mgl64.Vec3 {
+	switch a {
+	case X:
+		return mgl64.Vec3{1, 0, 0}
+	case Y:
+		return mgl64.Vec3{0, 1, 0}
+	default:
+		return mgl64.Vec3{0, 0, 1}
+	}
+}
+
+// Axes return all possible axes. (x, y, z)
+func Axes() []Axis {
+	return []Axis{X, Y, Z}
+}