scratch-vm/src/io/mouse.js
2023-12-15 17:40:05 -08:00

145 lines
4.5 KiB
JavaScript

const MathUtil = require('../util/math-util');
class Mouse {
constructor (runtime) {
this._x = 0;
this._y = 0;
this._isDown = false;
/**
* Reference to the owning Runtime.
* Can be used, for example, to activate hats.
* @type{!Runtime}
*/
this.runtime = runtime;
}
/**
* Activate "event_whenthisspriteclicked" hats.
* @param {Target} target to trigger hats on.
* @private
*/
_activateClickHats (target) {
// Activate both "this sprite clicked" and "stage clicked"
// They were separated into two opcodes for labeling,
// but should act the same way.
// Intentionally not checking isStage to make it work when sharing blocks.
// @todo the blocks should be converted from one to another when shared
this.runtime.startHats('event_whenthisspriteclicked',
null, target);
this.runtime.startHats('event_whenstageclicked',
null, target);
}
/**
* Find a target by XY location
* @param {number} x X position to be sent to the renderer.
* @param {number} y Y position to be sent to the renderer.
* @return {Target} the target at that location
* @private
*/
_pickTarget (x, y) {
if (this.runtime.renderer) {
const drawableID = this.runtime.renderer.pick(x, y);
for (let i = 0; i < this.runtime.targets.length; i++) {
const target = this.runtime.targets[i];
if (Object.prototype.hasOwnProperty.call(target, 'drawableID') &&
target.drawableID === drawableID) {
return target;
}
}
}
// Return the stage if no target was found
return this.runtime.getTargetForStage();
}
/**
* Mouse DOM event handler.
* @param {object} data Data from DOM event.
*/
postData (data) {
if (data.x) {
this._clientX = data.x;
this._scratchX = Math.round(MathUtil.clamp(
480 * ((data.x / data.canvasWidth) - 0.5),
-240,
240
));
}
if (data.y) {
this._clientY = data.y;
this._scratchY = Math.round(MathUtil.clamp(
-360 * ((data.y / data.canvasHeight) - 0.5),
-180,
180
));
}
if (typeof data.isDown !== 'undefined') {
const previousDownState = this._isDown;
this._isDown = data.isDown;
// Do not trigger if down state has not changed
if (previousDownState === this._isDown) return;
// Never trigger click hats at the end of a drag
if (data.wasDragged) return;
// Do not activate click hats for clicks outside canvas bounds
if (!(data.x > 0 && data.x < data.canvasWidth &&
data.y > 0 && data.y < data.canvasHeight)) return;
const target = this._pickTarget(data.x, data.y);
const isNewMouseDown = !previousDownState && this._isDown;
const isNewMouseUp = previousDownState && !this._isDown;
// Draggable targets start click hats on mouse up.
// Non-draggable targets start click hats on mouse down.
if (target.draggable && isNewMouseUp) {
this._activateClickHats(target);
} else if (!target.draggable && isNewMouseDown) {
this._activateClickHats(target);
}
}
}
/**
* Get the X position of the mouse in client coordinates.
* @return {number} Non-clamped X position of the mouse cursor.
*/
getClientX () {
return this._clientX;
}
/**
* Get the Y position of the mouse in client coordinates.
* @return {number} Non-clamped Y position of the mouse cursor.
*/
getClientY () {
return this._clientY;
}
/**
* Get the X position of the mouse in scratch coordinates.
* @return {number} Clamped and integer rounded X position of the mouse cursor.
*/
getScratchX () {
return this._scratchX;
}
/**
* Get the Y position of the mouse in scratch coordinates.
* @return {number} Clamped and integer rounded Y position of the mouse cursor.
*/
getScratchY () {
return this._scratchY;
}
/**
* Get the down state of the mouse.
* @return {boolean} Is the mouse down?
*/
getIsDown () {
return this._isDown;
}
}
module.exports = Mouse;