src/extras/PointerLens/PointerLens.js
/**
* A PointerLens shows a magnified view of a {@link Viewer}'s canvas, centered at the position of the
* mouse or touch pointer.
*
* This component is used by {@link DistanceMeasurementsControl} and {@link AngleMeasurementsControl}
* to help position the pointer when snap-to-vertex or snap-toedge is enabled.
*
* [[Run an example](https://xeokit.github.io/xeokit-sdk/examples/measurement/#distance_createWithMouse_snapping)]
*
* ````JavaScript
*
* import {Viewer, XKTLoaderPlugin, AngleMeasurementsPlugin, AngleMeasurementsMouseControl, PointerLens} from "../../dist/xeokit-sdk.es.js";
*
* const viewer = new Viewer({
* canvasId: "myCanvas",
* dtxEnabled: true
* });
*
* viewer.camera.eye = [-3.93, 2.85, 27.01];
* viewer.camera.look = [4.40, 3.72, 8.89];
* viewer.camera.up = [-0.01, 0.99, 0.039];
*
* const xktLoader = new XKTLoaderPlugin(viewer);
*
* const sceneModel = xktLoader.load({
* id: "myModel",
* src: "../../assets/models/xkt/v10/glTF-Embedded/Duplex_A_20110505.glTFEmbedded.xkt",
* edges: true
* });
*
* const angleMeasurements = new AngleMeasurementsPlugin(viewer);
*
* const angleMeasurementsMouseControl = new AngleMeasurementsMouseControl(angleMeasurements, {
* pointerLens : new PointerLens(viewer, {
* zoomFactor: 2
* })
* })
*
* angleMeasurementsMouseControl.activate();
* ````
*/
export class PointerLens {
/**
* Constructs a new PointerLens.
* @param viewer The Viewer
* @param [cfg] PointerLens configuration.
* @param [cfg.active=true] Whether PointerLens is active. The PointerLens can only be shown when this is `true` (default).
*/
constructor(viewer, cfg={}) {
this.viewer = viewer;
this.scene = this.viewer.scene;
this._lensCursorDiv = document.createElement('div');
this.viewer.scene.canvas.canvas.parentNode.insertBefore(this._lensCursorDiv, this.viewer.scene.canvas.canvas);
this._lensCursorDiv.style.background = "pink";
this._lensCursorDiv.style.border = "2px solid red";
this._lensCursorDiv.style.borderRadius = "20px";
this._lensCursorDiv.style.width = "10px";
this._lensCursorDiv.style.height = "10px";
this._lensCursorDiv.style.margin = "-200px -200px";
this._lensCursorDiv.style.zIndex = "100000";
this._lensCursorDiv.style.position = "absolute";
this._lensCursorDiv.style.pointerEvents = "none";
this._lensContainer = document.createElement('div');
this._lensContainer.style.border = "1px solid black";
this._lensContainer.style.background = "white";
// this._lensContainer.style.opacity = "0";
this._lensContainer.style.borderRadius = "50%";
this._lensContainer.style.width = "300px";
this._lensContainer.style.height = "300px";
this._lensContainer.style.marginTop = "85px";
this._lensContainer.style.marginLeft = "25px";
this._lensContainer.style.zIndex = "15000";
this._lensContainer.style.position = "absolute";
this._lensContainer.style.pointerEvents = "none";
this._lensContainer.style.visibility = "hidden";
this._lensCanvas = document.createElement('canvas');
// this._lensCanvas.style.background = "darkblue";
this._lensCanvas.style.borderRadius = "50%";
this._lensCanvas.style.width = "300px";
this._lensCanvas.style.height = "300px";
this._lensCanvas.style.zIndex = "15000";
this._lensCanvas.style.pointerEvents = "none";
document.body.appendChild(this._lensContainer);
this._lensContainer.appendChild(this._lensCanvas);
this._lensCanvasContext = this._lensCanvas.getContext('2d');
this._canvasElement = this.viewer.scene.canvas.canvas;
this._canvasPos = null;
this._snappedCanvasPos = null;
this._lensPosToggle = true;
this._zoomLevel = cfg.zoomLevel || 2;
this._active = (cfg.active !== false);
this._visible = false;
this._snapped = false;
this._onViewerRendering = this.viewer.scene.on("rendering", () => {
if (this._active && this._visible) {
this.update();
}
});
}
/**
* Updates this PointerLens.
*/
update() {
if (!this._active || !this._visible) {
return;
}
if (!this._canvasPos) {
return;
}
const lensRect = this._lensContainer.getBoundingClientRect();
const canvasRect = this._canvasElement.getBoundingClientRect();
const pointerOnLens =
this._canvasPos[0] < lensRect.right && this._canvasPos[0] > lensRect.left &&
this._canvasPos[1] < lensRect.bottom && this._canvasPos[1] > lensRect.top;
this._lensContainer.style.marginLeft = `25px`;
if (pointerOnLens) {
if (this._lensPosToggle) {
this._lensContainer.style.marginTop = `${canvasRect.bottom - canvasRect.top - this._lensCanvas.height - 85}px`;
} else {
this._lensContainer.style.marginTop = `85px`;
}
this._lensPosToggle = !this._lensPosToggle;
}
this._lensCanvasContext.clearRect(0, 0, this._lensCanvas.width, this._lensCanvas.height);
const size = Math.max(this._lensCanvas.width, this._lensCanvas.height) / this._zoomLevel;
this._lensCanvasContext.drawImage(
this._canvasElement, // source canvas
this._canvasPos[0] - size / 2, // source x (zoom center)
this._canvasPos[1] - size / 2, // source y (zoom center)
size, // source width
size, // source height
0, // destination x
0, // destination y
this._lensCanvas.width, // destination width
this._lensCanvas.height // destination height
);
const centerLensCanvas = [
(lensRect.left + lensRect.right) / 2 - canvasRect.left,
(lensRect.top + lensRect.bottom) / 2 - canvasRect.top
];
if (this._snappedCanvasPos) {
const deltaX = this._snappedCanvasPos[0] - this._canvasPos[0];
const deltaY = this._snappedCanvasPos[1] - this._canvasPos[1];
this._lensCursorDiv.style.marginLeft = `${centerLensCanvas[0] + deltaX * this._zoomLevel - 10}px`;
this._lensCursorDiv.style.marginTop = `${centerLensCanvas[1] + deltaY * this._zoomLevel - 10}px`;
} else {
this._lensCursorDiv.style.marginLeft = `${centerLensCanvas[0] - 10}px`;
this._lensCursorDiv.style.marginTop = `${centerLensCanvas[1] - 10}px`;
}
}
/**
* Sets the zoom factor for the lens.
*
* This is `2` by default.
*
* @param zoomFactor
*/
set zoomFactor(zoomFactor) {
this._zoomFactor = zoomFactor;
this.update();
}
/**
* Gets the zoom factor for the lens.
*
* This is `2` by default.
*
* @returns Number
*/
get zoomFactor() {
return this._zoomFactor;
}
/**
* Sets the canvas central position of the lens.
* @param canvasPos
*/
set canvasPos(canvasPos) {
this._canvasPos = canvasPos;
this.update();
}
/**
* Gets the canvas central position of the lens.
* @returns {Number[]}
*/
get canvasPos() {
return this._canvasPos;
}
/**
* Sets the canvas coordinates of the pointer.
* @param snappedCanvasPos
*/
set snappedCanvasPos(snappedCanvasPos) {
this._snappedCanvasPos = snappedCanvasPos;
this.update();
}
/**
* Gets the canvas coordinates of the snapped pointer.
* @returns {Number[]}
*/
get snappedCanvasPos() {
return this._snappedCanvasPos;
}
/**
* Sets if the cursor has snapped to anything.
* This is set by plugins.
* @param snapped
* @private
*/
set snapped(snapped) {
this._snapped = snapped;
if (snapped) {
this._lensCursorDiv.style.background = "greenyellow";
this._lensCursorDiv.style.border = "2px solid green";
} else {
this._lensCursorDiv.style.background = "pink";
this._lensCursorDiv.style.border = "2px solid red";
}
}
/**
* Gets if the cursor has snapped to anything.
* This is called by plugins.
* @returns {Boolean}
* @private
*/
get snapped() {
return this._snapped;
}
/**
* Sets if this PointerLens is active.
* @param active
*/
set active(active) {
this._active = active;
this._lensContainer.style.visibility = (active && this._visible) ? "visible" : "hidden";
if (!active || !this._visible ) {
this._lensCursorDiv.style.marginLeft = `-100px`;
this._lensCursorDiv.style.marginTop = `-100px`;
}
this.update();
}
/**
* Gets if this PointerLens is active.
* @returns {Boolean}
*/
get active() {
return this._active;
}
/**
* Sets if this PointerLens is visible.
* This is set by plugins.
* @param visible
* @private
*/
set visible(visible) {
this._visible = visible;
this._lensContainer.style.visibility = (visible && this._active) ? "visible" : "hidden";
if (!visible || !this._active) {
this._lensCursorDiv.style.marginLeft = `-100px`;
this._lensCursorDiv.style.marginTop = `-100px`;
}
this.update();
}
/**
* Gets if this PointerLens is visible.
* This is called by plugins.
* @returns {Boolean}
* @private
*/
get visible() {
return this._visible;
}
/**
* Destroys this PointerLens.
*/
destroy() {
if (!this._destroyed) {
this.viewer.scene.off(this._onViewerRendering);
this._lensContainer.removeChild(this._lensCanvas);
document.body.removeChild(this._lensContainer);
this._destroyed = true;
}
}
}
