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beebot/imageex.js
2018-01-03 14:04:57 +01:00

299 lines
9.3 KiB
JavaScript

const _ = require('lodash');
const fs = require('fs');
const got = require('got');
const Canvas = require('canvas');
const streamBuffers = require('stream-buffers');
const mime = require('mime-types');
const { GifReader } = require('omggif');
const GifEncoder = require('gifencoder');
const { Image } = Canvas;
function loadFromUri(uri) {
if (uri.startsWith('http')) {
return got(uri, { encoding: null }).then(res => ({
type: res.headers['content-type'],
data: res.body
}));
}
return new Promise((resolve, reject) => {
fs.readFile(uri, (err, data) => {
if (err) reject(err);
resolve({
type: mime.lookup(uri),
data
});
});
});
}
function createCanvas(width, height) {
const canvas = new Canvas(width, height);
return canvas;
}
function _drawImage(ctx, img, x, y, args = {}) {
if (args.transform) {
ctx.save();
_.each(args.transform, (val, prop) => {
console.log('Transform: ', prop, val);
ctx[prop](...val);
});
}
if (args.sx !== undefined || args.sy !== undefined || args.swidth !== undefined || args.sheight !== undefined) {
ctx.drawImage(img, args.sx, args.sy, args.swidth, args.sheight, x, y, args.width || args.swidth, args.height || args.sheight);
} else {
ctx.drawImage(img, x, y, args.width, args.height);
}
if (args.transform) {
ctx.restore();
}
}
class ImageEx {
constructor(uri) {
this.uri = uri;
this.loaded = loadFromUri(uri).then(result => {
this.type = result.type;
this.data = result.data;
if (this.type === 'image/gif') {
console.log(uri, 'loaded');
this.initGif();
} else {
this.initStatic();
}
return this;
});
}
initGif() {
const reader = new GifReader(new Uint8Array(this.data));
this.width = reader.width;
this.height = reader.height;
console.log('Decoding frames');
this.frames = this.decodeFrames(reader);
console.log('Frames decoded!');
this.renderAllFrames();
return this;
}
initStatic() {
const img = new Image();
img.src = this.data;
this.width = img.width;
this.height = img.height;
this.frames = [{
actualOffset: 0,
actualDelay: Infinity,
delay: Infinity
}];
this.spriteSheet = createCanvas(this.width, this.height);
const spriteSheetCtx = this.spriteSheet.getContext('2d');
spriteSheetCtx.drawImage(img, 0, 0);
}
decodeFrames(reader) {
const frames = [];
let offset = 0;
for (let i = 0; i < reader.numFrames(); ++i) {
const frameInfo = reader.frameInfo(i);
frameInfo.pixels = new Uint8ClampedArray(reader.width * reader.height * 4);
reader.decodeAndBlitFrameRGBA(i, frameInfo.pixels);
frameInfo.buffer = this.createBufferCanvas(frameInfo, this.width, this.height);
frameInfo.actualOffset = offset;
frameInfo.actualDelay = Math.max(frameInfo.delay * 10, 20);
offset += frameInfo.actualDelay;
frames.push(frameInfo);
}
this.totalDuration = offset;
return frames;
}
renderAllFrames() {
let disposeFrame = null;
const canvas = createCanvas(this.width, this.height);
const ctx = canvas.getContext('2d');
let saved;
this.spriteSheet = createCanvas((this.width + 1) * this.frames.length, this.height);
const spriteSheetCtx = this.spriteSheet.getContext('2d');
for (let i = 0; i < this.frames.length; ++i) {
const frame = this.frames[i];
if (typeof disposeFrame === 'function') disposeFrame();
switch (frame.disposal) {
case 2:
disposeFrame = () => ctx.clearRect(0, 0, canvas.width, canvas.height);
break;
case 3:
saved = ctx.getImageData(0, 0, canvas.width, canvas.height);
disposeFrame = () => ctx.putImageData(saved, 0, 0); // eslint-disable-line no-loop-func
break;
default:
this.disposeFrame = null;
}
// draw current frame
ctx.drawImage(frame.buffer, frame.x, frame.y);
// draw the frame onto the sprite sheet
spriteSheetCtx.drawImage(canvas, (this.width + 1) * i, 0);
}
}
createBufferCanvas(frame, width, height) {
const canvas = createCanvas(frame.width, frame.height);
const ctx = canvas.getContext('2d');
const imageData = ctx.createImageData(width, height);
imageData.data.set(frame.pixels);
ctx.putImageData(imageData, -frame.x, -frame.y);
return canvas;
}
drawFrame(ctx, frameNum, x, y, args = {}) {
const sx = frameNum * (this.width + 1) + (args.sx || 0);
const sy = args.sy || 0;
const swidth = Math.min(args.swidth || this.width, this.width) - (args.sx || 0);
const sheight = args.sheight || this.height;
console.log(`Drawing frame ${frameNum} at`);
console.log('sx', sx);
console.log('sy', sy);
console.log('sw', swidth);
console.log('sh', sheight);
console.log('x', x);
console.log('y', y);
console.log('w', args.width);
console.log('h', args.height);
_drawImage(ctx, this.spriteSheet, x, y, {
sx, sy, swidth, sheight, width: args.width || swidth, height: args.height || sheight, transform: args.transform
});
// ctx.drawImage(this.spriteSheet, 0, 0, 112, 112, 0, 0, 112, 112)
}
}
class CanvasEx {
constructor(width, height) {
this.width = Math.round(width);
this.height = Math.round(height);
this.frames = [];
this.totalDuration = Infinity;
}
addFrame(actualDelay, delay) {
if ((actualDelay === undefined || actualDelay === null)
&& (delay === undefined || delay === null)) throw new Error('Delay has to be set!');
const canvas = createCanvas(this.width, this.height);
if (!Number.isNaN(delay) && delay <= 1) {
delay = 10;
}
const frame = {
actualOffset: this.totalDuration,
delay: delay || Math.max(Math.round(actualDelay / 10), 2),
actualDelay: actualDelay || Math.max(delay * 10, 20),
canvas,
ctx: canvas.getContext('2d')
};
this.totalDuration += delay;
this.frames.push(frame);
}
drawImage(img, x, y, args = {}) {
console.log('Drawing image ', img);
console.log('At ', x, y, args);
if (img.frames && img.frames.length > 1) {
if (this.frames.length > 1) throw new Error('Cannot render animations onto animated canvases!');
this.totalDuration = img.totalDuration;
// we are drawing an animated image onto a static one.
// for each frame in the image, create a frame on this one, cloning the original picture (if any),
// render the original on each frame, and draw the frame on top.
for (let i = this.frames.length; i < img.frames.length; ++i) {
const frame = img.frames[i];
// console.log(`Adding frame ${i}:`, frame);
this.addFrame(null, frame.delay);
if (this.frames.length > 0) {
this.frames[i].ctx.antialias = 'none';
_drawImage(this.frames[i].ctx, this.frames[0].canvas, 0, 0, { width: this.width, height: this.height });
this.frames[i].ctx.antialias = 'default';
}
}
for (let i = 0; i < img.frames.length; ++i) {
// console.log(`Drawing frame ${i}:`, img.frames[i]);
// draw the i-th source frame to the i-th target frame
img.drawFrame(this.frames[i].ctx, i, x, y, args);
}
} else {
// we are drawing a static image on top of a (possibly animated) image.
// for each frame, just draw, nothing fancy.
if (img.frames) { // eslint-disable-line no-lonely-if
// the image cant have more than one frame, and if it has 0, we dont need to do anything at all
if (img.frames.length === 1) {
// if theres no frames at all, add one
if (this.frames.length === 0) {
this.addFrame(Infinity);
}
for (let i = 0; i < this.frames.length; ++i) {
img.drawFrame(this.frames[i].ctx, 0, x, y, args);
}
}
} else {
for (let i = 0; i < this.frames.length; ++i) {
_drawImage(this.frames[i].ctx, img, x, y, args);
}
}
}
}
drawFrame(ctx, frameNum, x, y, args = {}) {
_drawImage(ctx, this.frames[frameNum].canvas, x, y, args);
}
export(outStream) {
if (this.frames.length > 1) {
if (outStream.setHeader) outStream.setHeader('Content-Type', 'image/gif');
const gif = new GifEncoder(this.width, this.height);
gif.createReadStream().pipe(outStream);
// gif.setTransparent(0xfefe01);
gif.setRepeat(0);
gif.start();
for (let i = 0; i < this.frames.length; ++i) {
const frame = this.frames[i];
gif.setDelay(frame.actualDelay);
gif.addFrame(frame.ctx);
}
gif.finish();
} else if (this.frames.length === 1) {
if (outStream.setHeader) outStream.setHeader('Content-Type', 'image/png');
const stream = this.frames[0].canvas.pngStream();
stream.pipe(outStream);
} else {
throw new Error('No image data to be exported');
}
}
toBuffer() {
const buf = new streamBuffers.WritableStreamBuffer({
initialSize: this.height * this.width * 4 * this.frames.length,
incrementAmount: this.height * this.width * 4
});
this.export(buf);
return new Promise(resolve => {
buf.on('finish', () => {
console.log('Render completed (1)');
resolve(buf.getContents());
});
});
}
}
module.exports = {
CanvasEx,
ImageEx
};