KorMA Geometry

KorMA provides some geometry utilities.

Table of contents:

Angle

Angle is an inline class backed by a Double that represents an angle and that can give additional type safety and semantics to code. It can be constructed from and converted to degrees and radians and offer several utilities and operators related to angles:

inline class Angle(val radians: Double)

fun cos(angle: Angle): Double
fun sin(angle: Angle): Double
fun tan(angle: Angle): Double

inline val Number.degrees: Angle
inline val Number.radians: Angle

val Angle.degrees: Double
val Angle.radians: Double

val Angle.normalized: Angle

Point and Matrix

Point and Matrix are classes holding doubles (to get consistency among targets including JavaScript) that represent a 2D Point (with x and y) and a 2D Affine Transform Matrix (with a, b, c, d, tx and ty).

Vector3D and Matrix3D

Vector3D and Matrix3D are vectors and matrices of 4 components / 4 rows and 4 columns. They can also be used as 2, 3 and 4 component vectors, and 2x2, 3x3 and 4x4 matrices.

AABB3D & Sphere3D

data class Sphere3D(val origin: Vector3, val radius: Float) {
}

data class AABB3D(val min: Vector3 = Vector3(), val max: Vector3) {
    var minX: Float
    var minY: Float
    var minZ: Float
    var maxX: Float
    var maxY: Float
    var maxZ: Float
    val sizeX: Float
    val sizeY: Float
    val sizeZ: Float

    companion object {
        operator fun invoke(min: Float = Float.POSITIVE_INFINITY, max: Float = Float.NEGATIVE_INFINITY): AABB3D
        fun fromSphere(pos: IVector3, radius: Float): AABB3D
    }

    fun setX(min: Float, max: Float)
    fun setY(min: Float, max: Float)
    fun setZ(min: Float, max: Float)
    fun copyFrom(other: AABB3D)
    fun expandBy(that: AABB3D)
    fun expandToFit(that: AABB3D)
    fun expandedBy(that: AABB3D, out: AABB3D = AABB3D()): AABB3D
    fun intersectsSphere(sphere: Sphere3D): Boolean
    fun intersectsSphere(origin: Vector3, radius: Float): Boolean
    fun intersectsAABB(box: AABB3D): Boolean
    fun clone(): AABB3D
}

BoundsBuilder

BoundsBuilder is a class that allows to compute the bounds of a set of points without additional allocations.

class BoundsBuilder {
    fun reset()
    fun add(x: Double, y: Double): BoundsBuilder
    fun getBounds(out: Rectangle = Rectangle()): Rectangle
}

inline fun BoundsBuilder.add(x: Number, y: Number)
fun BoundsBuilder.add(p: IPoint)
fun BoundsBuilder.add(ps: Iterable<IPoint>)
fun BoundsBuilder.add(ps: IPointArrayList)
fun BoundsBuilder.add(rect: Rectangle)

PointArrayList

PointArrayList and PointIntArrayList can be used to store a list of points (pair of numbers) without allocating objects per element. You can later access x and y components with getX and getY or convert them into a list of Point for convenience that actually allocate objects.

class PointArrayList(capacity: Int = 7) {
    constructor(capacity: Int = 7, callback: PointArrayList.() -> Unit)
    constructor(points: List<IPoint>): PointArrayList
    constructor(vararg points: IPoint): PointArrayList

    val size: Int
    fun isEmpty(): Boolean
    fun isNotEmpty(): Boolean
    fun add(x: Double, y: Double)
    fun getX(index: Int)
    fun getY(index: Int)

    fun setX(index: Int, x: Double)
    fun setY(index: Int, y: Double)
    fun setXY(index: Int, x: Double, y: Double)
    fun reverse()
    fun sort()
}

fun PointArrayList.getPoint(index: Int): Point
fun PointArrayList.toPoints(): List<Point>
inline fun IPointArrayList.contains(x: Number, y: Number): Boolean

inline fun PointArrayList.add(x: Number, y: Number)
fun PointArrayList.add(p: Point)
fun PointArrayList.add(other: PointArrayList)
inline fun PointArrayList.setX(index: Int, x: Number)
inline fun PointArrayList.setY(index: Int, y: Number)
inline fun PointArrayList.setXY(index: Int, x: Number, y: Number)

Rectangle, Size, Anchor, Orientation and ScaleMode

data class Rectangle(
    var x: Double, var y: Double,
    var width: Double, var height: Double
) : MutableInterpolable<Rectangle>, Interpolable<Rectangle>, IRectangle, Sizeable

inline class Size(val p: Point) : MutableInterpolable<Size>, Interpolable<Size>, ISize, Sizeable

data class Anchor(val sx: Double, val sy: Double) : Interpolable<Anchor>

enum class Orientation(val value: Int) { CW(+1), CCW(-1), COLLINEAR(0) }

class ScaleMode {
    operator fun invoke(item: Size, container: Size, target: Size = Size()): Size

    companion object {
        val COVER: ScaleMode
        val SHOW_ALL: ScaleMode
        val EXACT: ScaleMode
        val NO_SCALE: ScaleMode
    }
}

As a sample combining most of these entities:

assertEquals(
    Rectangle(0, -150, 600, 600),
    Size(100, 100).applyScaleMode(
        Rectangle(0, 0, 600, 300),
        ScaleMode.COVER,
        Anchor.MIDDLE_CENTER
    )
)

Ray, Ray3D

class Ray {
	val point: Point
	val direction: Vector2D
}

class Ray3D {
	val pos: Vector3D
	val dir: Vector3D
	
    fun transformed(mat: Matrix3D): Ray3D
    
	companion object {
        fun fromPoints(p1: Vector3D, p2: Vector3D): Ray3D
    }
}

fun Ray3D.intersectRayAABox1(box: AABB3D) : Boolean 

EulerRotation & Quaternion


class EulerRotation {
    var x: Angle = 0.degrees,
    var y: Angle = 0.degrees,
    var z: Angle = 0.degrees

    companion object {
        fun toQuaternion(roll: Angle, pitch: Angle, yaw: Angle, out: Quaternion = Quaternion()): Quaternion
        fun toQuaternion(euler: EulerRotation, out: Quaternion = Quaternion()): Quaternion
    }

    fun toQuaternion(out: Quaternion = Quaternion()): Quaternion
    fun setQuaternion(x: Double, y: Double, z: Double, w: Double): EulerRotation
    fun setQuaternion(x: Int, y: Int, z: Int, w: Int): EulerRotation
    fun setQuaternion(x: Float, y: Float, z: Float, w: Float): EulerRotation

    fun setQuaternion(quaternion: Quaternion): EulerRotation
    fun setTo(x: Angle, y: Angle, z: Angle): EulerRotation
    fun setTo(other: EulerRotation): EulerRotation
    fun toMatrix(out: Matrix3D = Matrix3D()): Matrix3D
}

// https://en.wikipedia.org/wiki/Conversion_between_quaternions_and_Euler_angles
class Quaternion {
    var x: Double = 0.0,
    var y: Double = 0.0,
    var z: Double = 0.0,
    var w: Double = 1.0

    val xyz: Vector3D

    constructor(xyz: IVector3, w: Double)

    val lengthSquared: Double
    val length: Double

    companion object {
        fun dotProduct(l: Quaternion, r: Quaternion): Double
        operator fun invoke(x: Float, y: Float, z: Float, w: Float): Quaternion
        operator fun invoke(x: Int, y: Int, z: Int, w: Int): Quaternion
        fun toEuler(q: Quaternion, out: EulerRotation = EulerRotation()): EulerRotation
        fun toEuler(x: Double, y: Double, z: Double, w: Double, euler: EulerRotation
        fun toEuler(x: Int, y: Int, z: Int, w: Int, euler: EulerRotation = EulerRotation()): EulerRotation
        fun toEuler(x: Float, y: Float, z: Float, w: Float, out: EulerRotation = EulerRotation()): EulerRotation
    }

    operator fun get(index: Int): Double
    inline fun setToFunc(callback: (Int) -> Double)
    fun setTo(x: Double, y: Double, z: Double, w: Double): Quaternion
    fun setTo(x: Int, y: Int, z: Int, w: Int): Quaternion
    fun setTo(x: Float, y: Float, z: Float, w: Float): Quaternion
    fun setTo(euler: EulerRotation): Quaternion
    fun setTo(other: Quaternion): Quaternion

    fun setEuler(x: Angle, y: Angle, z: Angle): Quaternion
    fun setEuler(euler: EulerRotation): Quaternion

    fun copyFrom(other: Quaternion): Quaternion

    operator fun unaryMinus(): Quaternion
    operator fun plus(other: Quaternion): Quaternion
    operator fun minus(other: Quaternion): Quaternion
    operator fun times(scale: Double): Quaternion

    fun negate()

    inline fun setToFunc(l: Quaternion, r: Quaternion, func: (l: Double, r: Double) -> Double)
    fun setToSlerp(left: Quaternion, right: Quaternion, t: Double, tleft: Quaternion = Quaternion(), tright: Quaternion = Quaternion()): Quaternion
    fun setToNlerp(left: Quaternion, right: Quaternion, t: Double): Quaternion
    fun setToInterpolated(left: Quaternion, right: Quaternion, t: Double): Quaternion
    fun setFromRotationMatrix(m: Matrix3D): Quaternion
    fun normalize(v: Quaternion = this): Quaternion
    fun toMatrix(out: Matrix3D = Matrix3D()): Matrix3D
    fun inverted(out: Quaternion = Quaternion()): Quaternion

    operator fun times(other: Quaternion): Quaternion
    fun transform(vec: Vector3D, out: Vector3D = Vector3D()): Vector3D
}

BVH

N-dimensional Bounding Volume Hierarchy implementation

class BVH<T> {
	data class IntersectResult<T>(val intersect: Double, val obj: Node<T>)
}

BVH2D

A Bounding Volume Hierarchy implementation for 2D. It uses Rectangle to describe volumes and Ray for raycasting.

open class BVH2D<T>(val allowUpdateObjects: Boolean = true) {
    val bvh = BVH<T>(allowUpdateObjects = allowUpdateObjects)
    fun intersectRay(ray: Ray, rect: Rectangle? = null): BVHIntervals?
    fun envelope(): Rectangle
    fun intersect(ray: Ray, return_array = fastArrayListOf()): FastArrayList<IntersectResult<T>>
    fun search(rect: IRectangle, return_array = fastArrayListOf()): FastArrayList<BVH.Node<T>>
    fun insertOrUpdate(rect: IRectangle, obj: T)
    fun remove(rect: IRectangle, obj: T? = null)
    fun remove(obj: T)
    fun getObjectBounds(obj: T, out: Rectangle = Rectangle()): Rectangle
    fun debug()
}

fun BVHIntervals.toRectangle(out: Rectangle = Rectangle())
fun IRectangle.toBVH(out: BVHIntervals = BVHIntervals(2)): BVHIntervals
fun Ray.toBVH(out: BVHIntervals = BVHIntervals(2)): BVHIntervals

BVH3D

A Bounding Volume Hierarchy implementation for 3D. It uses AABB3D to describe volumes and Ray3D for raycasting.

open class BVH3D<T>(val allowUpdateObjects: Boolean = true) {
    val bvh = BVH<T>(allowUpdateObjects = allowUpdateObjects)
    fun intersectRay(ray: Ray3D, rect: AABB3D? = null): BVHIntervals?
    fun envelope(): AABB3D
    fun intersect(ray: Ray3D, return_array = fastArrayListOf()): FastArrayList<BVH.IntersectResult<T>>
    fun search(rect: AABB3D, return_array = fastArrayListOf()): FastArrayList<BVH.Node<T>>
    fun insertOrUpdate(rect: AABB3D, obj: T)
    fun remove(rect: AABB3D, obj: T? = null)
    fun remove(obj: T)
    fun getObjectBounds(obj: T, out: AABB3D = AABB3D()): AABB3D?
    fun debug()
}

fun BVHIntervals.toAABB3D(out: AABB3D = AABB3D()): AABB3D
fun AABB3D.toBVH(out: BVHIntervals = BVHIntervals(3)): BVHIntervals
fun Ray3D.toBVH(out: BVHIntervals = BVHIntervals(3)): BVHIntervals