ol-games/control/FrameRate.js
2022-09-16 11:34:04 +02:00

86 lines
2.4 KiB
JavaScript

/* Copyright (c) 2017 Jean-Marc VIGLINO,
released under the CeCILL-B license (French BSD license)
(http://www.cecill.info/licences/Licence_CeCILL-B_V1-en.txt).
*/
import ol_control_Control from 'ol/control/Control'
import ol_Observable from 'ol/Observable'
import ol_ext_element from 'ol-ext/util/element'
/**
* @classdesc A control to display frame rate as histogram.
*
* @constructor
* @extends {ol.control.Control}
* @param {Object=} Control options.
*
*/
var ol_control_FrameRate = class olcontrolFrameRate extends ol_control_Control {
constructor(opt_options) {
var options = opt_options || {};
var element = ol_ext_element.create('DIV', {
className: (options.className || "ol-framerate") + (options.target ? '' : ' ol-unselectable ol-control')
});
super({
element: element,
target: options.target
});
var canvas = this.canvas_ = document.createElement('canvas');
canvas.width = 100;
canvas.height = 40;
element.appendChild(canvas);
this.ctx = canvas.getContext('2d');
this.ctx.font = "bold 11px sans-serif";
this.ctx.textAlign = "center";
this.ctx.textBaseline = "top";
this.ctx.fillStyle = "#fff";
this.ctx.fillRect(1, 15, 99, 45);
}
/**
* @param {ol.Map} map The map instance.
*/
setMap(map) {
if (this._listener)
ol_Observable.unByKey(this._listener);
this._listener = null;
ol_control_Control.prototype.setMap.call(this, map);
if (this.getMap()) {
this._listener = this.getMap().on("precompose", this.update_.bind(this));
this.time_ = (new Date()).getTime();
}
}
update_(e) {
var dt = e.frameState.time - this.time;
this.time = e.frameState.time;
// Move image left
this.ctx.drawImage(this.canvas_, 1, 15, 99, this.canvas_.height, 0, 15, 99, this.canvas_.height);
// Draw text
var fps = Math.round(500 / dt);
this.ctx.clearRect(0, 0, 100, 15);
this.ctx.fillStyle = "#000";
this.ctx.fillText((2 * fps) + " fps", 50, 0);
this.ctx.strokeStyle = "#fff";
this.ctx.beginPath();
this.ctx.moveTo(100, 15);
this.ctx.lineTo(100, 40);
this.ctx.closePath();
this.ctx.stroke();
this.ctx.strokeStyle = (fps > 20 ? "#060" : fps > 12 ? "#f80" : "#800");
this.ctx.beginPath();
this.ctx.moveTo(100, 40 - fps / 2);
this.ctx.lineTo(100, 40);
this.ctx.closePath();
this.ctx.stroke();
}
}
export default ol_control_FrameRate