Canvas_Draw/index.html at main · cs60apa/Canvas_Draw · GitHub

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<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Canvas Draw</title>
    <link rel="stylesheet" href="/css/styles.css" />
  </head>
  <body>
    <!-- Heading Canvas Draw App -->
    <h1>Canvas Drawing App</h1>

    <div id="controls">
      <!-- Label for the color picker -->
      <label for="colorpicker">Color:</label>
      <input type="color" value="#000000" id="colorpicker" />

      <!-- Brush -->
      <label for="brush"> Brush Size:</label>
      <input type="range" min="1" max="50" value="5" id="brushSize" />

      <!-- Button -->
      <button id="clearBtn">Clear Canvas</button>
    </div>
    <!-- Canvas -->
    <canvas id="canvas" width="600" height="300"> </canvas>

    <!-- Internal JavaScript -->
    <script>
      const canvas = document.getElementById("canvas");
      const ctx = canvas.getContext("2d");
      const colorPicker = document.getElementById("colorpicker");
      const brushSize = document.getElementById("brushSize");
      const clearBtn = document.getElementById("clearBtn");

      let painting = false;

      // Draw dot where a user should start from
      function startPosition(e) {
        painting = true;
        draw(e);
      }

      // Stop drawing
      function endPosition() {
        painting = false;
        ctx.beginPath();
      }

      // Draw
      function draw(e) {
        if (!painting) return;

        ctx.lineWidth = brushSize.value;
        ctx.lineCap = "round"; // It makes the line caps rounded
        ctx.strokeStyle = colorPicker.value;

        ctx.lineTo(e.clientX - canvas.offsetLeft, e.clientY - canvas.offsetTop);
        ctx.stroke();
        ctx.beginPath();
        ctx.moveTo(e.clientX - canvas.offsetLeft, e.clientY - canvas.offsetTop);
      }

      canvas.addEventListener('mousedown', startPosition);
      canvas.addEventListener('mouseup', endPosition);
      canvas.addEventListener('mousemove', draw);
      clearBtn.addEventListener('click', ()=>{
        ctx.clearRect(5, 5, canvas.width, canvas.height);
      });


    </script>
  </body>
</html>