fullscreen drawing

.gitignore

@@ -1,3 +1,5 @@
 
 .env
 tmp
+
+node_modules

.vscode/settings.json

@@ -0,0 +1,3 @@
+{
+    "typescript.tsdk": "node_modules/typescript/lib"
+}

js/draw.js

@@ -1,101 +1,101 @@
+"use strict";
 (() => {
-  const canvas = document.getElementById("drawCanvas");
+    const drawElement = document.getElementById("drawDiv");
-  const ctx = canvas.getContext("2d");
+    if (!drawElement) {
-
+        throw new Error("canvas not found");
-  ctx.lineWidth = 2;
+    }
-  ctx.lineCap = "round";
+    const drawEmitter = mitt();
-  ctx.strokeStyle = "white";
-
     let drawing = false;
-  let lineId = 0;
+    const socketUrl = "/draw/ws";
-
-  const socketUrl =
-    (window.location.protocol.startsWith("https") ? "wss://" : "ws://") +
-    window.location.host +
-    "/draw/ws";
-
     let socket = new WebSocket(socketUrl);
-
     socket.onerror = console.error;
     socket.onclose = console.warn;
-
+    const serializeDraw = ({ from, to }) => `${from.x},${from.y},${to.x},${to.y}`;
-  setTimeout(() => socket.send("ping"), 200);
+    const deserializeDraw = (message) => {
-
+        const parts = message.split(",");
-  // const queue = []
+        return {
-
+            from: {
-  const sendMessage = (id, x, y) => {
+                x: Number(parts[0]),
-    // queue.push(`${id},${x},${y}`)
+                y: Number(parts[1]),
-
+            },
-    // console.log(queue)
+            to: {
-
+                x: Number(parts[2]),
+                y: Number(parts[3]),
+            },
+        };
+    };
+    drawEmitter.on("draw", (e) => sendMessage(e));
+    const sendMessage = (e) => {
         if (socket.readyState !== socket.OPEN) {
             socket = new WebSocket(socketUrl);
         }
-
+        socket.send(serializeDraw(e));
-    socket.send(id + "," + x + "," + y);
     };
-
+    const mouseDown = () => {
-  const drawStart = () => {
-    ctx.beginPath();
-    lineId++;
         drawing = true;
+        previous = null;
     };
-
+    const mouseUp = () => {
-  const drawStop = () => {
         drawing = false;
-    ctx.closePath();
     };
-
+    let previous = null;
-  const drawMove = (e) => {
+    const mouseMove = (e) => {
-    if (!drawing) return;
+        if (!drawing)
-    ctx.lineTo(e.offsetX, e.offsetY);
+            return;
-    sendMessage(lineId, e.offsetX, e.offsetY);
+        if (previous) {
-    ctx.stroke();
+            drawEmitter.emit("draw", {
-  };
+                from: previous,
-
+                to: { x: e.offsetX, y: e.offsetY },
-  const touchStart = (e) => drawStart(e.touches[0]);
-  const touchMove = (e) => {
-    drawMove({
-      offsetX: e.touches[0].clientX - canvas.offsetLeft,
-      offsetY: e.touches[0].clientY - canvas.offsetTop,
             });
-    e.preventDefault();
+        }
+        previous = { x: e.offsetX, y: e.offsetY };
     };
-  const touchEnd = (e) => drawStop(e.changedTouches[0]);
+    const touchMove = (e) => {
-
+        e.preventDefault();
-  canvas.addEventListener("mousedown", drawStart);
+        mouseMove({
-  canvas.addEventListener("mouseup", drawStop);
+            offsetX: e.touches[0].clientX - drawElement.offsetLeft,
-  canvas.addEventListener("mousemove", drawMove);
+            offsetY: e.touches[0].clientY - drawElement.offsetTop,
-
+        });
-  canvas.addEventListener("touchstart", touchStart);
+    };
-  canvas.addEventListener("touchend", touchEnd);
+    drawElement.addEventListener("mousedown", mouseDown);
-  canvas.addEventListener("touchmove", touchMove);
+    drawElement.addEventListener("mouseup", mouseUp);
-
+    drawElement.addEventListener("mousemove", mouseMove);
+    drawElement.addEventListener("touchstart", mouseDown);
+    drawElement.addEventListener("touchend", mouseUp);
+    drawElement.addEventListener("touchmove", touchMove);
     const receiveCanvas = document.getElementById("receiveCanvas");
-  const recCtx = receiveCanvas.getContext("2d");
+    const recCtx = receiveCanvas?.getContext("2d");
+    if (!recCtx || !receiveCanvas) {
+        throw new Error("canvas not found");
+    }
+    //@ts-expect-error
+    window.ctx = recCtx;
+    setTimeout(() => {
         recCtx.lineWidth = 2;
         recCtx.lineCap = "round";
         recCtx.strokeStyle = "white";
-
+    }, 10);
-  let receiveLineId = 0;
+    socket.addEventListener("message", (event) => {
-
+        if (event.data === "ping" || event.data.startsWith('pong'))
-  socket.addEventListener("message", function (event) {
+            return;
-    const parts = event.data.split(",");
+        const { from, to } = deserializeDraw(event.data);
-    if (parts[0] != receiveLineId) {
-      recCtx.closePath();
         recCtx.beginPath();
-      receiveLineId = parts[0];
+        recCtx.moveTo(from.x, from.y);
-      recCtx.moveTo(parts[1], parts[2]);
+        recCtx.lineTo(to.x, to.y);
-    } else {
+        recCtx.closePath();
-      recCtx.lineTo(parts[1], parts[2]);
         recCtx.stroke();
-    }
+        console.log(from, to);
     });
-
     setInterval(() => {
         if (socket.readyState !== socket.OPEN) {
             socket = new WebSocket(socketUrl);
         }
         socket.send("ping");
     }, 10000);
+    const resizeObserver = new ResizeObserver((entries) => {
+        const entry = entries.at(0);
+        receiveCanvas.height = entry?.contentRect.height ?? 500;
+        receiveCanvas.width = entry?.contentRect.width ?? 500;
+    });
+    resizeObserver.observe(drawElement);
 })();

js/draw.ts

@@ -0,0 +1,138 @@
+(() => {
+  const drawElement = document.getElementById(
+    "drawDiv"
+  ) as HTMLDivElement | null;
+  if (!drawElement) {
+    throw new Error("canvas not found");
+  }
+
+  type DrawPoint = {
+    x: number;
+    y: number;
+  };
+  type DrawEvent = {
+    from: DrawPoint;
+    to: DrawPoint;
+  };
+  type Events = {
+    draw: DrawEvent;
+  };
+
+  const drawEmitter = mitt<Events>();
+
+  let drawing = false;
+  const socketUrl = "/draw/ws";
+
+  let socket = new WebSocket(socketUrl);
+
+  socket.onerror = console.error;
+  socket.onclose = console.warn;
+
+  const serializeDraw = ({from, to }: DrawEvent) =>
+    `${from.x},${from.y},${to.x},${to.y}`;
+
+  const deserializeDraw = (message: string): DrawEvent => {
+    const parts = message.split(",");
+    return {
+      from: {
+        x: Number(parts[0]),
+        y: Number(parts[1]),
+      },
+      to: {
+        x: Number(parts[2]),
+        y: Number(parts[3]),
+      },
+    };
+  };
+
+  drawEmitter.on("draw", (e) => sendMessage(e));
+  const sendMessage = (e: DrawEvent) => {
+    if (socket.readyState !== socket.OPEN) {
+      socket = new WebSocket(socketUrl);
+    }
+    socket.send(serializeDraw(e));
+  };
+
+  const mouseDown = () => {
+    drawing = true;
+    previous=null
+  };
+
+  const mouseUp = () => {
+    drawing = false;
+  };
+
+  let previous: DrawPoint | null = null;
+  const mouseMove = (e: Pick<MouseEvent, "offsetX" | "offsetY">) => {
+    if (!drawing) return;
+    if (previous) {
+      drawEmitter.emit("draw", {
+        from: previous,
+        to: { x: e.offsetX, y: e.offsetY },
+      });
+    }
+    previous = { x: e.offsetX, y: e.offsetY };
+  };
+
+  const touchMove = (e: TouchEvent) => {
+    e.preventDefault();
+    mouseMove({
+      offsetX: e.touches[0].clientX - drawElement.offsetLeft,
+      offsetY: e.touches[0].clientY - drawElement.offsetTop,
+    });
+  };
+
+  drawElement.addEventListener("mousedown", mouseDown);
+  drawElement.addEventListener("mouseup", mouseUp);
+  drawElement.addEventListener("mousemove", mouseMove);
+
+  drawElement.addEventListener("touchstart", mouseDown);
+  drawElement.addEventListener("touchend", mouseUp);
+  drawElement.addEventListener("touchmove", touchMove);
+
+  const receiveCanvas = document.getElementById(
+    "receiveCanvas"
+  ) as HTMLCanvasElement | null;
+  const recCtx = receiveCanvas?.getContext("2d");
+
+  if (!recCtx || !receiveCanvas) {
+    throw new Error("canvas not found");
+  }
+  //@ts-expect-error
+  window.ctx = recCtx;
+
+  setTimeout(()=>{
+    recCtx.lineWidth = 2;
+    recCtx.lineCap = "round";
+    recCtx.strokeStyle = "white";
+  },10)
+
+
+
+
+  socket.addEventListener("message", (event) => {
+    if(event.data==="ping" || event.data.startsWith('pong')) return
+    const { from, to } = deserializeDraw(event.data);
+
+    recCtx.beginPath();
+    recCtx.moveTo(from.x, from.y);
+    recCtx.lineTo(to.x, to.y);
+    recCtx.closePath();
+    recCtx.stroke();
+    console.log(from, to);
+  });
+
+  setInterval(() => {
+    if (socket.readyState !== socket.OPEN) {
+      socket = new WebSocket(socketUrl);
+    }
+    socket.send("ping");
+  }, 10000);
+
+  const resizeObserver = new ResizeObserver((entries) => {
+    const entry = entries.at(0);
+    receiveCanvas.height = entry?.contentRect.height ?? 500;
+    receiveCanvas.width = entry?.contentRect.width ?? 500;
+  });
+  resizeObserver.observe(drawElement);
+})();

js/global.d.ts

@@ -0,0 +1,4 @@
+declare const mitt: {
+    //@ts-expect-error 
+    <T = any>(): import("mitt").Emitter<T>;
+  };

js/mitt/mitt.js

@@ -0,0 +1,2 @@
+function mitt (n){return{all:n=n||new Map,on:function(e,t){var i=n.get(e);i?i.push(t):n.set(e,[t])},off:function(e,t){var i=n.get(e);i&&(t?i.splice(i.indexOf(t)>>>0,1):n.set(e,[]))},emit:function(e,t){var i=n.get(e);i&&i.slice().map(function(n){n(t)}),(i=n.get("*"))&&i.slice().map(function(n){n(e,t)})}}};
+//# sourceMappingURL=mitt.js.map

package.json

@@ -0,0 +1,27 @@
+{
+  "name": "knet",
+  "version": "1.0.0",
+  "description": "",
+  "homepage": "https://github.com/JurajKubrican/knet#readme",
+  "bugs": {
+    "url": "https://github.com/JurajKubrican/knet/issues"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/JurajKubrican/knet.git"
+  },
+  "license": "ISC",
+  "author": "",
+  "type": "commonjs",
+  "main": "index.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1",
+    "dev": "tsc --project tsconfig.json --watch"
+  },
+  "devDependencies": {
+    "typescript": "^5.7.3"
+  },
+  "dependencies": {
+    "mitt": "^3.0.1"
+  }
+}

pnpm-lock.yaml

@@ -0,0 +1,33 @@
+lockfileVersion: '9.0'
+
+settings:
+  autoInstallPeers: true
+  excludeLinksFromLockfile: false
+
+importers:
+
+  .:
+    dependencies:
+      mitt:
+        specifier: ^3.0.1
+        version: 3.0.1
+    devDependencies:
+      typescript:
+        specifier: ^5.7.3
+        version: 5.7.3
+
+packages:
+
+  mitt@3.0.1:
+    resolution: {integrity: sha512-vKivATfr97l2/QBCYAkXYDbrIWPM2IIKEl7YPhjCvKlG3kE2gm+uBo6nEXK3M5/Ffh/FLpKExzOQ3JJoJGFKBw==}
+
+  typescript@5.7.3:
+    resolution: {integrity: sha512-84MVSjMEHP+FQRPy3pX9sTVV/INIex71s9TL2Gm5FG/WG1SqXeKyZ0k7/blY/4FdOzI12CBy1vGc4og/eus0fw==}
+    engines: {node: '>=14.17'}
+    hasBin: true
+
+snapshots:
+
+  mitt@3.0.1: {}
+
+  typescript@5.7.3: {}

tsconfig.json

@@ -0,0 +1,10 @@
+{
+  "compilerOptions": {
+    "target": "ESNext",
+    "module": "ESNext",
+    "moduleResolution": "Node",
+    "strict": true,
+    "esModuleInterop": true,
+      "types": ["./js/global.d.ts"]
+  }
+}

views/draw.html

@@ -1,21 +1,30 @@
 {{block "draw" .}}
-<div style="width:500px; height:500px">
   <canvas
     id="receiveCanvas"
     width="500"
     height="500"
-  style="position:absolute; border: 1px solid black ;background-color: transparent"
+    style="
-></canvas>
+      position: absolute;
-<canvas
+      background-color: transparent;
-  id="drawCanvas"
+      top: 0;
-  width="500"
+      left: 0;
-  height="500"
+      right: 0;
-  style="position:absolute; border: 1px solid black; background-color: transparent;"
+      bottom: 0;
-></canvas>
+    "
-
+  ></canvas>  
-<div>
+  <div
-
+    id="drawDiv"
-<script src="/js/draw.js">
+    style="
- 
+      position: absolute;
-</script>
+      background-color: transparent;
-{{end}}
+      top: 0;
+      left: 0;
+      right: 0;
+      bottom: 0;
+    "
+  ></div>
+    <script src="/js/mitt/mitt.js"></script>
+    <script src="/js/draw.js"></script>
+    {{end}}
+  </div>
+</div>

views/drawIndex.html

@@ -8,36 +8,11 @@
     <link rel="stylesheet" href="/css/main.css" />
   </head>
   <body>
-    <header>
-      <nav>
-        <ul>
-          <li>
-            <h1><a href="/">K</a></h1>
-          </li>
-        </ul>
-      </nav>
-    </header>
-
     <main>
       <section>
         {{template "draw" }}
       </section>
     </main>
-
-    <footer>
-      <nav>
-        <ul>
-          <li>
-            <a href="https://github.com/JurajKubrican">Github</a>
-          </li>
-          <li>
-            <a href="https://www.linkedin.com/in/juraj-kubri%C4%8Dan-614b3274/"
-              >LinkedIn</a
-            >
-          </li>
-        </ul>
-      </nav>
-    </footer>
   </body>
 </html>
 {{end}}