const canvas = document.getElementById('canvas'); const increaseBtn = document.getElementById('increase'); const decreaseBtn = document.getElementById('decrease'); const sizeEL = document.getElementById('size'); const colorEl = document.getElementById('color'); const clearEl = document.getElementById('clear'); const ctx = canvas.getContext('2d'); let size = 10 let isPressed = false colorEl.value = 'black' let color = colorEl.value let x let y canvas.addEventListener('mousedown', (e) => { isPressed = true x = e.offsetX y = e.offsetY }) document.addEventListener('mouseup', (e) => { isPressed = false x = undefined y = undefined }) canvas.addEventListener('mousemove', (e) => { if(isPressed) { const x2 = e.offsetX const y2 = e.offsetY drawCircle(x2, y2) drawLine(x, y, x2, y2) x = x2 y = y2 } }) function drawCircle(x, y) { ctx.beginPath(); ctx.arc(x, y, size, 0, Math.PI * 2) ctx.fillStyle = color ctx.fill() } function drawLine(x1, y1, x2, y2) { ctx.beginPath() ctx.moveTo(x1, y1) ctx.lineTo(x2, y2) ctx.strokeStyle = color ctx.lineWidth = size * 2 ctx.stroke() } function updateSizeOnScreen() { sizeEL.innerText = size } increaseBtn.addEventListener('click', () => { size += 5 if(size > 50) { size = 50 } updateSizeOnScreen() }) decreaseBtn.addEventListener('click', () => { size -= 5 if(size < 5) { size = 5 } updateSizeOnScreen() }) colorEl.addEventListener('change', (e) => color = e.target.value) clearEl.addEventListener('click', () => ctx.clearRect(0,0, canvas.width, canvas.height))