neihangif/server/build.js

const gifEncoder = require('gifencoder');
const Canvas = require('canvas');
const fs = require('fs');
const gifInfo = require('./config/gifInfo');

var task = 'sorry';
var target = gifInfo[task];
var ctxW = target.width;
var ctxH = target.height;
var encoder = new gifEncoder(ctxW, ctxH);

var startTime = new Date().getTime()
console.log(`正在生成gif...`);

encoder.createReadStream().pipe(fs.createWriteStream(`dist/${task}.gif`));
encoder.start();
encoder.setRepeat(0);
encoder.setDelay(1);
encoder.setQuality(10);

var canvas = new Canvas(ctxW, ctxH);
var ctx = canvas.getContext('2d');

function drawText(ctx, text, x, y) {
	ctx.fillStyle = "#ffffff";
	ctx.font = "16px Arial";
	ctx.textAlign = "center";
	ctx.fillText(text, x, y)
}

var imgObj = new Canvas.Image()
for (let i = 0; i <= target.size; i++) {
	imgObj.src = `res/${task}/image-${i}.png`
	ctx.drawImage(imgObj, 0, 0, ctxW, ctxH)

	target.textArr.forEach(n => {
		if(i >= n.arr[0] && i < n.arr[1]) {
			drawText(ctx, n.text, ctxW / 2, ctxH - 6)
		}
	})
	// ctx.fillStyle = '#ff0000';
	// ctx.fillRect(0, 0, ctxW, ctxH);
	encoder.addFrame(ctx)
}
encoder.finish()

var endTime = new Date().getTime() - startTime;
console.log(`成功生成，耗时：${endTime}ms`);