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script.js
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script.js
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const canvas = document.querySelector("canvas");
const form = document.querySelector(".sign-pad-form");
const clear = document.querySelector(".clear-button");
const ctx = canvas.getContext("2d");
let writingMode = false;
form.addEventListener("submit", (e) => {
e.preventDefault();
const imageURL = canvas.toDataURL();
const image = document.createElement("img");
image.src = imageURL;
image.height = canvas.height;
image.width = canvas.width;
image.style.display = "block";
form.appendChild(image);
clearPad();
});
clear.addEventListener("click", (e) => {
e.preventDefault();
clearPad();
});
const clearPad = () => {
ctx.clearRect(0, 0, canvas.width, canvas.height);
};
const getTargetPosition = (e) => {
positionX = e.clientX - e.target.getBoundingClientRect().x;
positionY = e.clientY - e.target.getBoundingClientRect().y;
return [positionX, positionY];
}
const handlePointerMove = (e) => {
if(!writingMode) return;
const [positionX, positionY] = getTargetPosition(e);
ctx.lineTo(positionX, positionY);
ctx.stroke();
}
const handlePointerUp = () => {
writingMode = false;
}
const handlePointerDown = (e) => {
writingMode = true;
ctx.beginPath();
const [positionX, positionY] = getTargetPosition(e);
ctx.moveTo(positionX, positionY);
};
const handleTouchMove = (e) => {
if(!writingMode) return;
e.preventDefault(); // Prevent scrolling
const touch = e.touches[0];
const [positionX, positionY] = getTargetPosition(touch);
ctx.lineTo(positionX, positionY);
ctx.stroke();
}
const handleTouchEnd = () => {
writingMode = false;
}
const handleTouchStart = (e) => {
writingMode = true;
ctx.beginPath();
const touch = e.touches[0];
const [positionX, positionY] = getTargetPosition(touch);
ctx.moveTo(positionX, positionY);
};
ctx.lineWidth = 3;
ctx.lineJoin = ctx.linecap = "round";
canvas.addEventListener("pointerdown", handlePointerDown, {passive: true});
canvas.addEventListener("pointerup", handlePointerUp, {passive: true});
canvas.addEventListener("pointermove", handlePointerMove, {passive: true});
canvas.addEventListener("touchstart", handleTouchStart, { passive: true });
canvas.addEventListener("touchend", handleTouchEnd, { passive: true });
canvas.addEventListener("touchmove", handleTouchMove, { passive: true });