@awayjs/core/lib/projections/OrthographicProjection.ts

AwayJS core classes

import { Vector3D } from '../geom/Vector3D';

import { ProjectionBase } from './ProjectionBase';
import { CoordinateSystem } from './CoordinateSystem';

export class OrthographicProjection extends ProjectionBase {
	constructor(scale: number = 1,  coordinateSystem: CoordinateSystem = CoordinateSystem.LEFT_HANDED) {
		super(coordinateSystem);

		this.scale = scale;
	}

	/**
	 *
	 * @param position
	 * @param target
	 */
	public project(position: Vector3D, target: Vector3D = null): Vector3D {
		const v: Vector3D = this.viewMatrix3D.transformVector(position, target);

		v.y = -v.y;
		v.z = (v.z * (this._far - this._near) + this._far + this._near) / 2;
		v.w = 1;

		return v;
	}

	/**
	 *
	 * @param nX
	 * @param nY
	 * @param sZ
	 * @param target
	 */
	public unproject(nX: number, nY: number, sZ: number, target: Vector3D = null): Vector3D {
		if (target == null)
			target = new Vector3D();

		target.x = nX * sZ;
		target.y = -nY * sZ;
		target.z = (sZ * 2 - this._far - this._near) / (this._far - this._near);
		target.w = 1;

		this.inverseViewMatrix3D.transformVector(target, target);

		target.w = 1;

		return target;
	}

	//@override
	public clone(): ProjectionBase {
		const clone: OrthographicProjection = new OrthographicProjection(this.scale, this._coordinateSystem);

		clone._near = this._near;
		clone._far = this._far;
		clone._coordinateSystem = this._coordinateSystem;

		return clone;
	}

	//@override
	public _updateFrustumMatrix3D(): void {
		super._updateFrustumMatrix3D();

		const raw: Float32Array = this._frustumMatrix3D._rawData;

		const scaleV: number = this._scale;
		const scaleH: number = this._scale / this._ratio;

		this._frustumRect.left = 0.5 * (this._originX - 1) / scaleH;
		this._frustumRect.top = 0.5 * (this._originY - 1) / scaleV;

		this._frustumRect.right = this._frustumRect.left + 1 / scaleH;
		this._frustumRect.bottom = this._frustumRect.top + 1 / scaleV;

		raw[0] = 2 * scaleH; //2/(right - left);
		raw[5] = 2 * scaleV; //2/(bottom - top);
		raw[12] = this._originX; //(right + left)/(right - left)
		raw[13] = this._originY; //(bottom + top)/(bottom - top);
		raw[10] = 2 / (this._far - this._near);
		raw[14] = -(this._far + this._near) / (this._far - this._near);
		raw[1] = raw[2] = raw[3] = raw[4] = raw[6] = raw[7] = raw[8] = raw[9] = raw[11] = 0;
		raw[15] = 1;
	}

	protected _updateProperties(): void {
		super._updateProperties();

		const rawData: Float32Array = this._frustumMatrix3D._rawData;

		this._near = -(rawData[14] + 1) / rawData[10];
		this._far = -(rawData[14] - 1) / rawData[10];
		this._originX = rawData[8];
		this._originY = rawData[9];
		this._scale = rawData[5] / 2;
		this._ratio = 0.5 * this._scale / rawData[0];
	}
}