src/viewer/scene/camera/Frustum.js
import {Component} from '../Component.js';
import {RenderState} from '../webgl/RenderState.js';
import {math} from '../math/math.js';
/**
* @desc Defines its {@link Camera}'s perspective projection as a frustum-shaped view volume.
*
* * Located at {@link Camera#frustum}.
* * Allows to explicitly set the positions of the left, right, top, bottom, near and far planes, which is useful for asymmetrical view volumes, such as for stereo viewing.
* * {@link Frustum#near} and {@link Frustum#far} specify the distances to the WebGL clipping planes.
*/
class Frustum extends Component {
/**
@private
*/
get type() {
return "Frustum";
}
/**
* @constructor
* @private
*/
constructor(camera, cfg = {}) {
super(camera, cfg);
/**
* The Camera this Frustum belongs to.
*
* @property camera
* @type {Camera}
* @final
*/
this.camera = camera;
this._state = new RenderState({
matrix: math.mat4(),
inverseMatrix: math.mat4(),
transposedMatrix: math.mat4(),
near: 0.1,
far: 10000.0
});
this._left = -1.0;
this._right = 1.0;
this._bottom = -1.0;
this._top = 1.0;
this._inverseMatrixDirty = true;
this._transposedMatrixDirty = true;
// Set component properties
this.left = cfg.left;
this.right = cfg.right;
this.bottom = cfg.bottom;
this.top = cfg.top;
this.near = cfg.near;
this.far = cfg.far;
}
_update() {
math.frustumMat4(this._left, this._right, this._bottom, this._top, this._state.near, this._state.far, this._state.matrix);
this._inverseMatrixDirty = true;
this._transposedMatrixDirty = true;
this.glRedraw();
this.fire("matrix", this._state.matrix);
}
/**
* Sets the position of the Frustum's left plane on the View-space X-axis.
*
* Fires a {@link Frustum#left:emits} emits on change.
*
* @param {Number} value New left frustum plane position.
*/
set left(value) {
this._left = (value !== undefined && value !== null) ? value : -1.0;
this._needUpdate(0);
this.fire("left", this._left);
}
/**
* Gets the position of the Frustum's left plane on the View-space X-axis.
*
* @return {Number} Left frustum plane position.
*/
get left() {
return this._left;
}
/**
* Sets the position of the Frustum's right plane on the View-space X-axis.
*
* Fires a {@link Frustum#right:emits} emits on change.
*
* @param {Number} value New right frustum plane position.
*/
set right(value) {
this._right = (value !== undefined && value !== null) ? value : 1.0;
this._needUpdate(0);
this.fire("right", this._right);
}
/**
* Gets the position of the Frustum's right plane on the View-space X-axis.
*
* Fires a {@link Frustum#right:emits} emits on change.
*
* @return {Number} Right frustum plane position.
*/
get right() {
return this._right;
}
/**
* Sets the position of the Frustum's top plane on the View-space Y-axis.
*
* Fires a {@link Frustum#top:emits} emits on change.
*
* @param {Number} value New top frustum plane position.
*/
set top(value) {
this._top = (value !== undefined && value !== null) ? value : 1.0;
this._needUpdate(0);
this.fire("top", this._top);
}
/**
* Gets the position of the Frustum's top plane on the View-space Y-axis.
*
* Fires a {@link Frustum#top:emits} emits on change.
*
* @return {Number} Top frustum plane position.
*/
get top() {
return this._top;
}
/**
* Sets the position of the Frustum's bottom plane on the View-space Y-axis.
*
* Fires a {@link Frustum#bottom:emits} emits on change.
*
* @emits {"bottom"} event with the value of this property whenever it changes.
*
* @param {Number} value New bottom frustum plane position.
*/
set bottom(value) {
this._bottom = (value !== undefined && value !== null) ? value : -1.0;
this._needUpdate(0);
this.fire("bottom", this._bottom);
}
/**
* Gets the position of the Frustum's bottom plane on the View-space Y-axis.
*
* Fires a {@link Frustum#bottom:emits} emits on change.
*
* @return {Number} Bottom frustum plane position.
*/
get bottom() {
return this._bottom;
}
/**
* Sets the position of the Frustum's near plane on the positive View-space Z-axis.
*
* Fires a {@link Frustum#near:emits} emits on change.
*
* Default value is ````0.1````.
*
* @param {Number} value New Frustum near plane position.
*/
set near(value) {
this._state.near = (value !== undefined && value !== null) ? value : 0.1;
this._needUpdate(0);
this.fire("near", this._state.near);
}
/**
* Gets the position of the Frustum's near plane on the positive View-space Z-axis.
*
* Fires a {@link Frustum#near:emits} emits on change.
*
* Default value is ````0.1````.
*
* @return {Number} Near frustum plane position.
*/
get near() {
return this._state.near;
}
/**
* Sets the position of the Frustum's far plane on the positive View-space Z-axis.
*
* Fires a {@link Frustum#far:emits} emits on change.
*
* Default value is ````10000.0````.
*
* @param {Number} value New far frustum plane position.
*/
set far(value) {
this._state.far = (value !== undefined && value !== null) ? value : 10000.0;
this._needUpdate(0);
this.fire("far", this._state.far);
}
/**
* Gets the position of the Frustum's far plane on the positive View-space Z-axis.
*
* Default value is ````10000.0````.
*
* @return {Number} Far frustum plane position.
*/
get far() {
return this._state.far;
}
/**
* Gets the Frustum's projection transform matrix.
*
* Fires a {@link Frustum#matrix:emits} emits on change.
*
* Default value is ````[1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1]````.
*
* @returns {Number[]} The Frustum's projection matrix matrix.
*/
get matrix() {
if (this._updateScheduled) {
this._doUpdate();
}
return this._state.matrix;
}
/**
* Gets the inverse of {@link Frustum#matrix}.
*
* @returns {Number[]} The inverse orthographic projection matrix.
*/
get inverseMatrix() {
if (this._updateScheduled) {
this._doUpdate();
}
if (this._inverseMatrixDirty) {
math.inverseMat4(this._state.matrix, this._state.inverseMatrix);
this._inverseMatrixDirty = false;
}
return this._state.inverseMatrix;
}
/**
* Gets the transpose of {@link Frustum#matrix}.
*
* @returns {Number[]} The transpose of {@link Frustum#matrix}.
*/
get transposedMatrix() {
if (this._updateScheduled) {
this._doUpdate();
}
if (this._transposedMatrixDirty) {
math.transposeMat4(this._state.matrix, this._state.transposedMatrix);
this._transposedMatrixDirty = false;
}
return this._state.transposedMatrix;
}
/**
* Un-projects the given Canvas-space coordinates, using this Frustum projection.
*
* @param {Number[]} canvasPos Inputs 2D Canvas-space coordinates.
* @param {Number} screenZ Inputs Screen-space Z coordinate.
* @param {Number[]} screenPos Outputs 3D Screen/Clip-space coordinates.
* @param {Number[]} viewPos Outputs un-projected 3D View-space coordinates.
* @param {Number[]} worldPos Outputs un-projected 3D World-space coordinates.
*/
unproject(canvasPos, screenZ, screenPos, viewPos, worldPos) {
const canvas = this.scene.canvas.canvas;
const halfCanvasWidth = canvas.offsetWidth / 2.0;
const halfCanvasHeight = canvas.offsetHeight / 2.0;
screenPos[0] = (canvasPos[0] - halfCanvasWidth) / halfCanvasWidth;
screenPos[1] = (canvasPos[1] - halfCanvasHeight) / halfCanvasHeight;
screenPos[2] = screenZ;
screenPos[3] = 1.0;
math.mulMat4v4(this.inverseMatrix, screenPos, viewPos);
math.mulVec3Scalar(viewPos, 1.0 / viewPos[3]);
viewPos[3] = 1.0;
viewPos[1] *= -1;
math.mulMat4v4(this.camera.inverseViewMatrix, viewPos, worldPos);
return worldPos;
}
/** @private
*
*/
destroy() {
super.destroy();
this._state.destroy();
super.destroy();
}
}
export {Frustum};
