Привет всем, поэтому у меня есть очень сложный редактор холста, который позволяет пользователю выбирать фоновое видео, добавлять текст, gifs и Lott ie анимации, используя библиотеки Konva js и Gifler. Однако я прошел долгий путь, пытаясь ускорить работу моего приложения на холсте. Я много читал о закадровом холсте, но не совсем понимаю. Скажем, у меня есть обычный HTML объект холста, как бы я создал внеэкранный холст и выплюнул его обратно в браузер? В идеале я хотел бы иметь возможность получать изображения с холста в массиве со скоростью 30 кадров в секунду без задержки. У меня также есть другое беспокойство, что пока не поддерживается широкоэкранный холст в соответствии с caniuse.com . Всякий раз, когда я пытаюсь создать закадровый холст из своего холста, я всегда получаю:
Failed to execute 'transferControlToOffscreen' on
'HTMLCanvasElement': Cannot transfer control from a canvas that has a rendering context.
Как я уже говорил, я просто пытаюсь понять, как плавно отрисовать анимацию, но не уверен, как go об этом. Любая помощь здесь будет отличной. Вот код.
<template>
<div>
<button @click="render">Render</button>
<h2>Backgrounds</h2>
<template v-for="background in backgrounds">
<img
:src="background.poster"
class="backgrounds"
@click="changeBackground(background.video)"
/>
</template>
<h2>Images</h2>
<template v-for="image in images">
<img
:src="image.source"
@click="addImage(image)"
class="images"
/>
</template>
<br />
<button @click="addText">Add Text</button>
<button v-if="selectedNode" @click="removeNode">
Remove selected {{ selectedNode.type }}
</button>
<label>Font:</label>
<select v-model="selectedFont">
<option value="Arial">Arial</option>
<option value="Courier New">Courier New</option>
<option value="Times New Roman">Times New Roman</option>
<option value="Desoto">Desoto</option>
<option value="Kalam">Kalam</option>
</select>
<label>Font Size</label>
<input type="number" v-model="selectedFontSize" />
<label>Font Style:</label>
<select v-model="selectedFontStyle">
<option value="normal">Normal</option>
<option value="bold">Bold</option>
<option value="italic">Italic</option>
</select>
<label>Color:</label>
<input type="color" v-model="selectedColor" />
<button
v-if="selectedNode && selectedNode.type === 'text'"
@click="updateText"
>
Update Text
</button>
<template v-if="selectedNode && selectedNode.lottie">
<input type="text" v-model="text">
<button @click="updateAnim(selectedNode.image)">
Update Animation
</button>
</template>
<br />
<video
id="preview"
v-show="preview"
:src="preview"
:width="width"
:height="height"
preload="auto"
controls
/>
<a v-if="file" :href="file" download="dopeness.mp4">download</a>
<div id="container"></div>
</div>
</template>
<script>
import lottie from "lottie-web";
import * as anim from "../AEAnim/anim.json";
import * as anim2 from "../AEAnim/anim2.json";
import * as anim3 from "../AEAnim/anim3.json";
import * as anim4 from "../AEAnim/anim4.json";
import * as anim5 from "../AEAnim/anim5.json";
export default {
data() {
return {
source: null,
stage: null,
layer: null,
video: null,
animations: [],
text: "",
animationData: null,
captures: [],
backgrounds: [
{
poster: "/api/files/stock/3oref310k1uud86w/poster/poster.jpg",
video:
"/api/files/stock/3oref310k1uud86w/main/1080/3oref310k1uud86w_1080.mp4"
},
{
poster: "/api/files/stock/3yj2e30tk5x6x0ww/poster/poster.jpg",
video:
"/api/files/stock/3yj2e30tk5x6x0ww/main/1080/3yj2e30tk5x6x0ww_1080.mp4"
},
{
poster: "/api/files/stock/2ez931ik1mggd6j/poster/poster.jpg",
video:
"/api/files/stock/2ez931ik1mggd6j/main/1080/2ez931ik1mggd6j_1080.mp4"
},
{
poster: "/api/files/stock/yxrt4ej4jvimyk15/poster/poster.jpg",
video:
"/api/files/stock/yxrt4ej4jvimyk15/main/1080/yxrt4ej4jvimyk15_1080.mp4"
},
{
poster:
"https://images.costco-static.com/ImageDelivery/imageService?profileId=12026540&itemId=100424771-847&recipeName=680",
video: "/api/files/jedi/surfing.mp4"
},
{
poster:
"https://thedefensepost.com/wp-content/uploads/2018/04/us-soldiers-afghanistan-4308413-1170x610.jpg",
video: "/api/files/jedi/soldiers.mp4"
}
],
images: [
{ source: "/api/files/jedi/solo.jpg" },
{ source: "api/files/jedi/yoda.jpg" },
{ source: "api/files/jedi/yodaChristmas.jpg" },
{ source: "api/files/jedi/darthMaul.jpg" },
{ source: "api/files/jedi/darthMaul1.jpg" },
{ source: "api/files/jedi/trump.jpg" },
{ source: "api/files/jedi/hat.png" },
{ source: "api/files/jedi/trump.png" },
{ source: "api/files/jedi/bernie.png" },
{ source: "api/files/jedi/skywalker.png" },
{ source: "api/files/jedi/vader.gif" },
{ source: "api/files/jedi/vader2.gif" },
{ source: "api/files/jedi/yoda.gif" },
{ source: "api/files/jedi/kylo.gif" },
{
source: "https://media3.giphy.com/media/R3IxJW14a3QNa/source.gif",
animation: anim
},
{
source: "https://bestanimations.com/Text/Cool/cool-story-3.gif",
animation: anim2
},
{
source: "https://freefrontend.com/assets/img/css-text-animations/HTML-CSS-Animated-Text-Fill.gif",
animation: anim3
},
{
source: "api/files/jedi/zoomer.gif",
animation: anim4
},
{
source: "api/files/jedi/slider.gif",
animation: anim5
}
],
backgroundVideo: null,
imageGroups: [],
anim: null,
selectedNode: null,
selectedFont: "Arial",
selectedColor: "black",
selectedFontSize: 20,
selectedFontStyle: "normal",
width: 1920,
height: 1080,
texts: [],
preview: null,
file: null,
canvas: null
};
},
mounted: function() {
this.initCanvas();
},
methods: {
changeBackground(source) {
this.source = source;
this.video.src = this.source;
this.anim.stop();
this.anim.start();
this.video.play();
},
removeNode() {
if (this.selectedNode && this.selectedNode.type === "text") {
this.selectedNode.transformer.destroy(
this.selectedNode.text.transformer
);
this.selectedNode.text.destroy(this.selectedNode.text);
this.texts.splice(this.selectedNode.text.index - 1, 1);
this.selectedNode = null;
this.layer.draw();
} else if (this.selectedNode && this.selectedNode.type == "image") {
this.selectedNode.group.destroy(this.selectedNode);
this.imageGroups.splice(this.selectedNode.group.index - 1, 1);
if (this.selectedNode.lottie) {
clearTimeout(this.animations.interval);
this.selectedNode.lottie.destroy();
this.animations.splice(this.selectedNode.lottie.index - 1, 1);
}
this.selectedNode = null;
this.layer.draw();
}
},
async addImage(imageToAdd, isUpdate) {
let lottieAnimation = null;
let imageObj = null;
const type = imageToAdd.source.slice(imageToAdd.source.lastIndexOf("."));
const vm = this;
function process(img) {
return new Promise((resolve, reject) => {
img.onload = () => resolve({ width: img.width, height: img.height });
});
}
imageObj = new Image();
imageObj.src = imageToAdd.source;
imageObj.width = 200;
imageObj.height = 200;
await process(imageObj);
if (type === ".gif" && !imageToAdd.animation) {
const canvas = document.createElement("canvas");
canvas.setAttribute("id", "gif");
async function onDrawFrame(ctx, frame) {
ctx.drawImage(frame.buffer, frame.x, frame.y);
// redraw the layer
vm.layer.draw();
}
gifler(imageToAdd.source).frames(canvas, onDrawFrame);
canvas.onload = async () => {
canvas.parentNode.removeChild(canvas);
};
imageObj = canvas;
const gif = new Image();
gif.src = imageToAdd.source;
const gifImage = await process(gif);
imageObj.width = gifImage.width;
imageObj.height = gifImage.height;
} else if (imageToAdd.animation) {
if(!isUpdate){this.text = "new text";}
const canvas = document.createElement("canvas");
canvas.style.width = 1920;
canvas.style.height= 1080;
canvas.setAttribute("id", "animationCanvas");
const ctx = canvas.getContext("2d");
const div = document.createElement("div");
div.setAttribute("id", "animationContainer");
div.style.display = "none";
canvas.style.display = "none";
this.animationData = imageToAdd.animation.default;
for(let i =0; i <this.animationData.layers.length; i++){
for(let b =0; b<this.animationData.layers[i].t.d.k.length; b++){
this.animationData.layers[i].t.d.k[b].s.t = this.text;
}
}
lottieAnimation = lottie.loadAnimation({
container: div, // the dom element that will contain the animation
renderer: "svg",
loop: true,
autoplay: true,
animationData: this.animationData
});
lottieAnimation.imgSrc = imageToAdd.source;
lottieAnimation.text = this.text;
const svg = await div.getElementsByTagName("svg")[0];
const timer = setInterval(async () => {
const xml = new XMLSerializer().serializeToString(svg);
const svg64 = window.btoa(xml);
const b64Start = "data:image/svg+xml;base64,";
const image64 = b64Start + svg64;
imageObj = new Image({ width: canvas.width, height: canvas.height });
imageObj.src = image64;
await process(imageObj);
ctx.clearRect(0, 0, canvas.width, canvas.height);
ctx.drawImage(imageObj, 0, 0, canvas.width, canvas.height);
this.layer.batchDraw();
}, 1000 / 30);
this.animations.push({ lottie: lottieAnimation, interval: timer });
imageObj = canvas;
canvas.onload = async () => {
canvas.parentNode.removeChild(canvas);
};
}
const image = new Konva.Image({
x: 50,
y: 50,
image: imageObj,
width: imageObj.width,
height: imageObj.height,
position: (0, 0),
strokeWidth: 10,
stroke: "blue",
strokeEnabled: false
});
const group = new Konva.Group({
draggable: true
});
// add the shape to the layer
addAnchor(group, 0, 0, "topLeft");
addAnchor(group, imageObj.width, 0, "topRight");
addAnchor(group, imageObj.width, imageObj.height, "bottomRight");
addAnchor(group, 0, imageObj.height, "bottomLeft");
imageObj = null;
image.on("click", function () {
vm.hideAllHelpers();
vm.selectedNode = {
type: "image",
group,
lottie: lottieAnimation,
image: imageToAdd
};
if(lottieAnimation && lottieAnimation.text){vm.text = lottieAnimation.text}
group.find("Circle").show();
vm.layer.draw();
});
image.on("mouseover", function(evt) {
if (vm.selectedNode && vm.selectedNode.type === "image") {
const index = image.getParent().index;
const groupId = vm.selectedNode.group.index;
if (index != groupId) {
evt.target.strokeEnabled(true);
vm.layer.draw();
}
} else {
evt.target.strokeEnabled(true);
vm.layer.draw();
}
});
image.on("mouseout", function(evt) {
evt.target.strokeEnabled(false);
vm.layer.draw();
});
vm.hideAllHelpers();
group.find("Circle").show();
group.add(image);
vm.layer.add(group);
vm.imageGroups.push(group);
vm.selectedNode = {
type: "image",
group,
lottie: lottieAnimation,
image: imageToAdd
};
function update(activeAnchor) {
const group = activeAnchor.getParent();
let topLeft = group.get(".topLeft")[0];
let topRight = group.get(".topRight")[0];
let bottomRight = group.get(".bottomRight")[0];
let bottomLeft = group.get(".bottomLeft")[0];
let image = group.get("Image")[0];
let anchorX = activeAnchor.getX();
let anchorY = activeAnchor.getY();
// update anchor positions
switch (activeAnchor.getName()) {
case "topLeft":
topRight.y(anchorY);
bottomLeft.x(anchorX);
break;
case "topRight":
topLeft.y(anchorY);
bottomRight.x(anchorX);
break;
case "bottomRight":
bottomLeft.y(anchorY);
topRight.x(anchorX);
break;
case "bottomLeft":
bottomRight.y(anchorY);
topLeft.x(anchorX);
break;
}
image.position(topLeft.position());
let width = topRight.getX() - topLeft.getX();
let height = bottomLeft.getY() - topLeft.getY();
if (width && height) {
image.width(width);
image.height(height);
}
}
function addAnchor(group, x, y, name) {
let stage = vm.stage;
let layer = vm.layer;
let anchor = new Konva.Circle({
x: x,
y: y,
stroke: "#666",
fill: "#ddd",
strokeWidth: 2,
radius: 8,
name: name,
draggable: true,
dragOnTop: false
});
anchor.on("dragmove", function() {
update(this);
layer.draw();
});
anchor.on("mousedown touchstart", function() {
group.draggable(false);
this.moveToTop();
});
anchor.on("dragend", function() {
group.draggable(true);
layer.draw();
});
// add hover styling
anchor.on("mouseover", function() {
let layer = this.getLayer();
document.body.style.cursor = "pointer";
this.strokeWidth(4);
layer.draw();
});
anchor.on("mouseout", function() {
let layer = this.getLayer();
document.body.style.cursor = "default";
this.strokeWidth(2);
layer.draw();
});
group.add(anchor);
}
},
async updateAnim(image){
this.addImage(image, true);
this.removeNode();
},
hideAllHelpers() {
for (let i = 0; i < this.texts.length; i++) {
this.texts[i].transformer.hide();
}
for (let b = 0; b < this.imageGroups.length; b++) {
this.imageGroups[b].find("Circle").hide();
}
},
async startRecording(duration) {
const chunks = []; // here we will store our recorded media chunks (Blobs)
const stream = this.canvas.captureStream(30); // grab our canvas MediaStream
const rec = new MediaRecorder(stream, {
videoBitsPerSecond: 20000 * 1000
});
// every time the recorder has new data, we will store it in our array
rec.ondataavailable = e => chunks.push(e.data);
// only when the recorder stops, we construct a complete Blob from all the chunks
rec.onstop = async e => {
this.anim.stop();
const blob = new Blob(chunks, {
type: "video/webm"
});
this.preview = await URL.createObjectURL(blob);
const video = window.document.getElementById("preview");
const previewVideo = new Konva.Image({
image: video,
draggable: false,
width: this.width,
height: this.height
});
this.layer.add(previewVideo);
console.log("video", video);
video.addEventListener("ended", () => {
console.log("preview ended");
if (!this.file) {
const vid = new Whammy.fromImageArray(this.captures, 30);
this.file = URL.createObjectURL(vid);
}
previewVideo.destroy();
this.anim.stop();
this.anim.start();
this.video.play();
});
let seekResolve;
video.addEventListener("seeked", async () => {
if (seekResolve) seekResolve();
});
video.addEventListener("loadeddata", async () => {
let interval = 1 / 30;
let currentTime = 0;
while (currentTime <= duration && !this.file) {
video.currentTime = currentTime;
await new Promise(r => (seekResolve = r));
this.layer.draw();
let base64ImageData = this.canvas.toDataURL("image/webp");
this.captures.push(base64ImageData);
currentTime += interval;
video.currentTime = currentTime;
}
this.layer.draw();
});
};
rec.start();
setTimeout(() => rec.stop(), duration);
},
async render() {
this.captures = [];
this.preview = null;
this.file = null;
this.hideAllHelpers();
this.selectedNode = null;
this.video.currentTime = 0;
this.video.loop = false;
const duration = this.video.duration * 1000;
this.startRecording(duration);
this.layer.draw();
},
updateText() {
if (this.selectedNode && this.selectedNode.type === "text") {
const text = this.selectedNode.text;
const transformer = this.selectedNode.transformer;
text.fontSize(this.selectedFontSize);
text.fontFamily(this.selectedFont);
text.fontStyle(this.selectedFontStyle);
text.fill(this.selectedColor);
this.layer.draw();
}
},
addText() {
const vm = this;
const text = new Konva.Text({
text: "new text " + (vm.texts.length + 1),
x: 50,
y: 80,
fontSize: this.selectedFontSize,
fontFamily: this.selectedFont,
fontStyle: this.selectedFontStyle,
fill: this.selectedColor,
align: "center",
width: this.width * 0.5,
draggable: true
});
const transformer = new Konva.Transformer({
node: text,
keepRatio: true,
enabledAnchors: ["top-left", "top-right", "bottom-left", "bottom-right"]
});
text.on("click", async () => {
for (let i = 0; i < this.texts.length; i++) {
let item = this.texts[i];
if (item.index === text.index) {
let transformer = item.transformer;
this.selectedNode = { type: "text", text, transformer };
this.selectedFontSize = text.fontSize();
this.selectedFont = text.fontFamily();
this.selectedFontStyle = text.fontStyle();
this.selectedColor = text.fill();
vm.hideAllHelpers();
transformer.show();
transformer.moveToTop();
text.moveToTop();
vm.layer.draw();
break;
}
}
});
text.on("mouseover", () => {
transformer.show();
this.layer.draw();
});
text.on("mouseout", () => {
if (
(this.selectedNode &&
this.selectedNode.text &&
this.selectedNode.text.index != text.index) ||
(this.selectedNode && this.selectedNode.type === "image") ||
!this.selectedNode
) {
transformer.hide();
this.layer.draw();
}
});
text.on("dblclick", () => {
text.hide();
transformer.hide();
vm.layer.draw();
let textPosition = text.absolutePosition();
let stageBox = vm.stage.container().getBoundingClientRect();
let areaPosition = {
x: stageBox.left + textPosition.x,
y: stageBox.top + textPosition.y
};
let textarea = document.createElement("textarea");
window.document.body.appendChild(textarea);
textarea.value = text.text();
textarea.style.position = "absolute";
textarea.style.top = areaPosition.y + "px";
textarea.style.left = areaPosition.x + "px";
textarea.style.width = text.width() - text.padding() * 2 + "px";
textarea.style.height = text.height() - text.padding() * 2 + 5 + "px";
textarea.style.fontSize = text.fontSize() + "px";
textarea.style.border = "none";
textarea.style.padding = "0px";
textarea.style.margin = "0px";
textarea.style.overflow = "hidden";
textarea.style.background = "none";
textarea.style.outline = "none";
textarea.style.resize = "none";
textarea.style.lineHeight = text.lineHeight();
textarea.style.fontFamily = text.fontFamily();
textarea.style.transformOrigin = "left top";
textarea.style.textAlign = text.align();
textarea.style.color = text.fill();
let rotation = text.rotation();
let transform = "";
if (rotation) {
transform += "rotateZ(" + rotation + "deg)";
}
let px = 0;
let isFirefox =
navigator.userAgent.toLowerCase().indexOf("firefox") > -1;
if (isFirefox) {
px += 2 + Math.round(text.fontSize() / 20);
}
transform += "translateY(-" + px + "px)";
textarea.style.transform = transform;
textarea.style.height = "auto";
textarea.focus();
// start
function removeTextarea() {
textarea.parentNode.removeChild(textarea);
window.removeEventListener("click", handleOutsideClick);
text.show();
transformer.show();
transformer.forceUpdate();
vm.layer.draw();
}
function setTextareaWidth(newWidth) {
if (!newWidth) {
// set width for placeholder
newWidth = text.placeholder.length * text.fontSize();
}
// some extra fixes on different browsers
let isSafari = /^((?!chrome|android).)*safari/i.test(
navigator.userAgent
);
let isFirefox =
navigator.userAgent.toLowerCase().indexOf("firefox") > -1;
if (isSafari || isFirefox) {
newWidth = Math.ceil(newWidth);
}
let isEdge =
document.documentMode || /Edge/.test(navigator.userAgent);
if (isEdge) {
newWidth += 1;
}
textarea.style.width = newWidth + "px";
}
textarea.addEventListener("keydown", function(e) {
// hide on enter
// but don't hide on shift + enter
if (e.keyCode === 13 && !e.shiftKey) {
text.text(textarea.value);
removeTextarea();
}
// on esc do not set value back to node
if (e.keyCode === 27) {
removeTextarea();
}
});
textarea.addEventListener("keydown", function(e) {
let scale = text.getAbsoluteScale().x;
setTextareaWidth(text.width() * scale);
textarea.style.height = "auto";
textarea.style.height =
textarea.scrollHeight + text.fontSize() + "px";
});
function handleOutsideClick(e) {
if (e.target !== textarea) {
text.text(textarea.value);
removeTextarea();
}
}
setTimeout(() => {
window.addEventListener("click", handleOutsideClick);
});
// end
});
text.transformer = transformer;
this.texts.push(text);
this.layer.add(text);
this.layer.add(transformer);
this.hideAllHelpers();
this.selectedNode = { type: "text", text, transformer };
transformer.show();
this.layer.draw();
},
initCanvas() {
const vm = this;
this.stage = new Konva.Stage({
container: "container",
width: vm.width,
height: vm.height
});
this.layer = new Konva.Layer();
this.stage.add(this.layer);
let video = document.createElement("video");
video.setAttribute("id", "video");
video.setAttribute("ref", "video");
if (this.source) {
video.src = this.source;
}
video.preload = "auto";
video.loop = "loop";
video.style.display = "none";
this.video = video;
this.backgroundVideo = new Konva.Image({
image: vm.video,
draggable: false
});
this.video.addEventListener("loadedmetadata", function(e) {
vm.backgroundVideo.width(vm.width);
vm.backgroundVideo.height(vm.height);
});
this.video.addEventListener("ended", () => {
console.log("the video ended");
this.anim.stop();
this.anim.start();
this.video.loop = "loop";
this.video.play();
});
this.anim = new Konva.Animation(function() {
console.log("animation called");
// do nothing, animation just need to update the layer
}, vm.layer);
this.layer.add(this.backgroundVideo);
this.layer.batchDraw();
const canvas = document.getElementsByTagName("canvas")[0];
canvas.style.border = "3px solid red";
this.canvas = canvas;
}
}
};
</script>
<style scoped>
body {
margin: 0;
padding: 0;
background-color: #f0f0f0;
}
.backgrounds,
.images {
width: 100px;
height: 100px;
padding-left: 2px;
padding-right: 2px;
}
</style>