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<div class="editor">
<canvas id="canvas" style="background:#fff; border:1px inset #888" width="400" height="200"></canvas><br>
<button type="button" id="blackbtn">Black</button> <button type="button" id="whitebtn">White</button>
<button type="button" id="redbtn">Red</button> <button type="button" id="bluebtn">Blue</button><br>
pen size : <input type="number" id="pensize" value="1" min="1" max="99"><br>
<button type="button" id="sendbtn">Send</button>
</div>
<footer><a href="/about.html">About this site</a></footer>
</main>
</body>
<script type="text/javascript">
const canvas = document.getElementById('canvas');
const ctx = canvas.getContext('2d');
ctx.getImageData(0, 0, 1, 1); // to trigger librewolf's protection (and allow users to enable canvas before publishing)
//ctx.fillStyle = "black";
let isDrawing = false;
function startDrawing(event) {
event.preventDefault();
isDrawing = true;
draw(event);
}
function startDrawingTouch(event) {
event.preventDefault();
isDrawing = true;
drawTouch(event);
}
function draw(event) {
event.preventDefault();
if (!isDrawing) return;
const x = event.clientX - canvas.offsetLeft + window.pageXOffset;
const y = event.clientY - canvas.offsetTop + window.pageYOffset;
ctx.lineTo(x, y);
ctx.stroke();
}
function drawTouch(event) {
event.preventDefault();
if (!isDrawing) return;
const x = event.touches[0].clientX - canvas.offsetLeft + window.pageXOffset;
const y = event.touches[0].clientY - canvas.offsetTop + window.pageYOffset;
ctx.lineTo(x, y);
ctx.stroke();
}
function stopDrawing() {
event.preventDefault();
isDrawing = false;
ctx.beginPath();
}
canvas.addEventListener("mousedown", startDrawing);
canvas.addEventListener("mousemove", draw);
canvas.addEventListener("mouseup", stopDrawing);
canvas.addEventListener("mouseout", stopDrawing);
canvas.addEventListener("touchstart", startDrawingTouch);
canvas.addEventListener("touchmove", drawTouch);
canvas.addEventListener("touchend", stopDrawing);
canvas.addEventListener("touchcancel", stopDrawing);
function sendPic() {
fetch("/api/post", {
method: "POST",
body: JSON.stringify({ {{ if .threadId }}
thread: "{{.threadId}}",{{ end }}
picture: canvas.toDataURL("image/png")
}),
headers: {
"Content-type": "application/json; charset=UTF-8"
}
})
.then((response) => response.json())
.then((json) => {
if (json.status == "ok") {
location.reload();
}
});
}
const sendbtn = document.getElementById('sendbtn');
sendbtn.addEventListener("click", sendPic);
const blackbtn = document.getElementById('blackbtn');
blackbtn.addEventListener("click", () => {
ctx.strokeStyle="black";
});
const whitebtn = document.getElementById('whitebtn');
whitebtn.addEventListener("click", () => {
ctx.strokeStyle="white";
});
const redbtn = document.getElementById('redbtn');
redbtn.addEventListener("click", () => {
ctx.strokeStyle="red";
});
const bluebtn = document.getElementById('bluebtn');
bluebtn.addEventListener("click", () => {
ctx.strokeStyle="blue";
});
const pensize = document.getElementById('pensize');
pensize.addEventListener("change", () => {
ctx.lineWidth=pensize.value;
console.log(pensize.value)
});
</script>
</html>
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