import { ObservablePoint } from './ObservablePoint';
import { Matrix } from './Matrix';
/**
* Transform that takes care about its versions
*
* @class
* @memberof PIXI
*/
export class Transform
{
constructor()
{
/**
* The world transformation matrix.
*
* @member {PIXI.Matrix}
*/
this.worldTransform = new Matrix();
/**
* The local transformation matrix.
*
* @member {PIXI.Matrix}
*/
this.localTransform = new Matrix();
/**
* The coordinate of the object relative to the local coordinates of the parent.
*
* @member {PIXI.ObservablePoint}
*/
this.position = new ObservablePoint(this.onChange, this, 0, 0);
/**
* The scale factor of the object.
*
* @member {PIXI.ObservablePoint}
*/
this.scale = new ObservablePoint(this.onChange, this, 1, 1);
/**
* The pivot point of the displayObject that it rotates around.
*
* @member {PIXI.ObservablePoint}
*/
this.pivot = new ObservablePoint(this.onChange, this, 0, 0);
/**
* The skew amount, on the x and y axis.
*
* @member {PIXI.ObservablePoint}
*/
this.skew = new ObservablePoint(this.updateSkew, this, 0, 0);
/**
* The rotation amount.
*
* @protected
* @member {number}
*/
this._rotation = 0;
/**
* The X-coordinate value of the normalized local X axis,
* the first column of the local transformation matrix without a scale.
*
* @protected
* @member {number}
*/
this._cx = 1;
/**
* The Y-coordinate value of the normalized local X axis,
* the first column of the local transformation matrix without a scale.
*
* @protected
* @member {number}
*/
this._sx = 0;
/**
* The X-coordinate value of the normalized local Y axis,
* the second column of the local transformation matrix without a scale.
*
* @protected
* @member {number}
*/
this._cy = 0;
/**
* The Y-coordinate value of the normalized local Y axis,
* the second column of the local transformation matrix without a scale.
*
* @protected
* @member {number}
*/
this._sy = 1;
/**
* The locally unique ID of the local transform.
*
* @protected
* @member {number}
*/
this._localID = 0;
/**
* The locally unique ID of the local transform
* used to calculate the current local transformation matrix.
*
* @protected
* @member {number}
*/
this._currentLocalID = 0;
/**
* The locally unique ID of the world transform.
*
* @protected
* @member {number}
*/
this._worldID = 0;
/**
* The locally unique ID of the parent's world transform
* used to calculate the current world transformation matrix.
*
* @protected
* @member {number}
*/
this._parentID = 0;
}
/**
* Called when a value changes.
*
* @protected
*/
onChange()
{
this._localID++;
}
/**
* Called when the skew or the rotation changes.
*
* @protected
*/
updateSkew()
{
this._cx = Math.cos(this._rotation + this.skew._y);
this._sx = Math.sin(this._rotation + this.skew._y);
this._cy = -Math.sin(this._rotation - this.skew._x); // cos, added PI/2
this._sy = Math.cos(this._rotation - this.skew._x); // sin, added PI/2
this._localID++;
}
/**
* Updates the local transformation matrix.
*/
updateLocalTransform()
{
const lt = this.localTransform;
if (this._localID !== this._currentLocalID)
{
// get the matrix values of the displayobject based on its transform properties..
lt.a = this._cx * this.scale._x;
lt.b = this._sx * this.scale._x;
lt.c = this._cy * this.scale._y;
lt.d = this._sy * this.scale._y;
lt.tx = this.position._x - ((this.pivot._x * lt.a) + (this.pivot._y * lt.c));
lt.ty = this.position._y - ((this.pivot._x * lt.b) + (this.pivot._y * lt.d));
this._currentLocalID = this._localID;
// force an update..
this._parentID = -1;
}
}
/**
* Updates the local and the world transformation matrices.
*
* @param {PIXI.Transform} parentTransform - The parent transform
*/
updateTransform(parentTransform)
{
const lt = this.localTransform;
if (this._localID !== this._currentLocalID)
{
// get the matrix values of the displayobject based on its transform properties..
lt.a = this._cx * this.scale._x;
lt.b = this._sx * this.scale._x;
lt.c = this._cy * this.scale._y;
lt.d = this._sy * this.scale._y;
lt.tx = this.position._x - ((this.pivot._x * lt.a) + (this.pivot._y * lt.c));
lt.ty = this.position._y - ((this.pivot._x * lt.b) + (this.pivot._y * lt.d));
this._currentLocalID = this._localID;
// force an update..
this._parentID = -1;
}
if (this._parentID !== parentTransform._worldID)
{
// concat the parent matrix with the objects transform.
const pt = parentTransform.worldTransform;
const wt = this.worldTransform;
wt.a = (lt.a * pt.a) + (lt.b * pt.c);
wt.b = (lt.a * pt.b) + (lt.b * pt.d);
wt.c = (lt.c * pt.a) + (lt.d * pt.c);
wt.d = (lt.c * pt.b) + (lt.d * pt.d);
wt.tx = (lt.tx * pt.a) + (lt.ty * pt.c) + pt.tx;
wt.ty = (lt.tx * pt.b) + (lt.ty * pt.d) + pt.ty;
this._parentID = parentTransform._worldID;
// update the id of the transform..
this._worldID++;
}
}
/**
* Decomposes a matrix and sets the transforms properties based on it.
*
* @param {PIXI.Matrix} matrix - The matrix to decompose
*/
setFromMatrix(matrix)
{
matrix.decompose(this);
this._localID++;
}
/**
* The rotation of the object in radians.
*
* @member {number}
*/
get rotation()
{
return this._rotation;
}
set rotation(value) // eslint-disable-line require-jsdoc
{
if (this._rotation !== value)
{
this._rotation = value;
this.updateSkew();
}
}
}
/**
* A default (identity) transform
*
* @static
* @constant
* @member {PIXI.Transform}
*/
Transform.IDENTITY = new Transform();
