openmct/platform/features/plot/src/Canvas2DChart.js
Victor Woeltjen ac5ac8d34e [Build] Remove boilerplate from scripts
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2016-03-04 10:46:38 -08:00

118 lines
4.2 KiB
JavaScript

/*****************************************************************************
* Open MCT Web, Copyright (c) 2014-2015, United States Government
* as represented by the Administrator of the National Aeronautics and Space
* Administration. All rights reserved.
*
* Open MCT Web is licensed under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* http://www.apache.org/licenses/LICENSE-2.0.
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
* Open MCT Web includes source code licensed under additional open source
* licenses. See the Open Source Licenses file (LICENSES.md) included with
* this source code distribution or the Licensing information page available
* at runtime from the About dialog for additional information.
*****************************************************************************/
define(
[],
function () {
/**
* Create a new chart which uses Canvas's 2D API for rendering.
*
* @memberof platform/features/plot
* @constructor
* @implements {platform/features/plot.Chart}
* @param {CanvasElement} canvas the canvas object to render upon
* @throws {Error} an error is thrown if Canvas's 2D API is unavailable.
*/
function Canvas2DChart(canvas) {
this.canvas = canvas;
this.c2d = canvas.getContext('2d');
this.width = canvas.width;
this.height = canvas.height;
this.dimensions = [ this.width, this.height ];
this.origin = [ 0, 0 ];
if (!this.c2d) {
throw new Error("Canvas 2d API unavailable.");
}
}
// Convert from logical to physical x coordinates
Canvas2DChart.prototype.x = function (v) {
return ((v - this.origin[0]) / this.dimensions[0]) * this.width;
};
// Convert from logical to physical y coordinates
Canvas2DChart.prototype.y = function (v) {
return this.height -
((v - this.origin[1]) / this.dimensions[1]) * this.height;
};
// Set the color to be used for drawing operations
Canvas2DChart.prototype.setColor = function (color) {
var mappedColor = color.map(function (c, i) {
return i < 3 ? Math.floor(c * 255) : (c);
}).join(',');
this.c2d.strokeStyle = "rgba(" + mappedColor + ")";
this.c2d.fillStyle = "rgba(" + mappedColor + ")";
};
Canvas2DChart.prototype.clear = function () {
var canvas = this.canvas;
this.width = canvas.width;
this.height = canvas.height;
this.c2d.clearRect(0, 0, this.width, this.height);
};
Canvas2DChart.prototype.setDimensions = function (newDimensions, newOrigin) {
this.dimensions = newDimensions;
this.origin = newOrigin;
};
Canvas2DChart.prototype.drawLine = function (buf, color, points) {
var i;
this.setColor(color);
// Configure context to draw two-pixel-thick lines
this.c2d.lineWidth = 2;
// Start a new path...
if (buf.length > 1) {
this.c2d.beginPath();
this.c2d.moveTo(this.x(buf[0]), this.y(buf[1]));
}
// ...and add points to it...
for (i = 2; i < points * 2; i = i + 2) {
this.c2d.lineTo(this.x(buf[i]), this.y(buf[i + 1]));
}
// ...before finally drawing it.
this.c2d.stroke();
};
Canvas2DChart.prototype.drawSquare = function (min, max, color) {
var x1 = this.x(min[0]),
y1 = this.y(min[1]),
w = this.x(max[0]) - x1,
h = this.y(max[1]) - y1;
this.setColor(color);
this.c2d.fillRect(x1, y1, w, h);
};
return Canvas2DChart;
}
);