node-canvas-skia

node-canvas-skia (alpha)

node-canvas-skia is a skia node binding designed to enable GPU accelerated image rendering in desktop applications. We expect to implement the same API as web canvas.

Note:

1. It has not yet fully stabilized and is currently in the testing phase.
2. GPU rendering has not been released yet.

Install

npm install node-canvas-skia

安装时会自动使用预编译的 .node 文件，无需本地编译环境。

如需从源码编译，可设置环境变量：

BUILD_FROM_SOURCE=true npm install node-canvas-skia

Platform

Example

const path = require("path");
const skia = require("node-canvas-skia");

const canvas = new skia.Canvas(256, 256);
const ctx = canvas.getContext("2d", { antialias: true });

const scale = 256;
const R = 0.45 * scale;
const TAU = 6.2831853;
ctx.beginPath();
ctx.moveTo(R, 0);
for (let i = 1; i < 7; ++i) {
  const theta = (3 * i * TAU) / 7;
  ctx.lineTo(R * Math.cos(theta), R * Math.sin(theta));
}
ctx.closePath();
ctx.translate(0.5 * scale, 0.5 * scale);
ctx.strokeStyle = "rgba(255,0,0,1)";
ctx.lineWidth = 2;
ctx.stroke();
ctx.translate(-0.5 * scale, -0.5 * scale);

canvas.saveAsImage(path.resolve(__dirname, "heptagram.jpg"));

API

1. Canvas
   • getContext
   • saveAsImage
   • toBuffer
   • save
   • restore
2. CanvasContext
   • textAlign
   • textBaseline
   • letterSpacing
   • globalAlpha
   • beginPath
   • moveTo
   • lineTo
   • closePath
   • stroke
   • clear
   • translate
   • rotate
   • strokeStyle
   • fillStyle
   • lineWidth
   • arc
   • strokeRect
   • lineCap
   • transform
   • fill
   • rect
   • isPointInPath
   • scale
   • arcTo
   • setFont
   • strokeText
   • fillText
   • measureText
   • getFonts
   • createLinearGradient
   • createRadialGradient
   • createConicGradient
   • fillRect
   • clearRect
   • strokeRect
   • drawImage
   • loadFont
   • roundRect
   • setLineDash
   • quadraticCurveTo
   • bezierCurveTo
   • clip
3. Gradient
   • addColorStop

license

Copyright (c) 2011 The node-skia Authors. All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

* Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. * Neither the name of Google Inc. nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.