Why Isn\'t My Image Appearing on the HTML5 Canvas?

Adding Images to an HTML5 Canvas

Incorporating images into your HTML5 canvas can enhance its functionality and visual appeal. However, if your image isn't appearing on the canvas despite properly setting the image source and drawing the image, consider the following:

It's essential to ensure that the image has fully loaded before attempting to draw it on the canvas. If you draw the image before it's ready, it won't display.

To resolve this issue and ensure the image is properly displayed:

1. Use an onload Event Handler: Attach an onload event handler to the image element. This handler will be called when the image has finished loading.
2. Draw the Image in the onload Callback: Within the onload event handler, use the context.drawImage() method to draw the image on the canvas.

Here's an updated code snippet that demonstrates this approach:

<code class="js">var canvas = document.getElementById('viewport'),
context = canvas.getContext('2d');

make_base();

function make_base()
{
  base_image = new Image();
  base_image.src = 'img/base.png';
  base_image.onload = function(){
    context.drawImage(base_image, 100, 100);
  }
}</code>

By using the onload callback, you ensure that the image is fully loaded before it's drawn on the canvas, resolving the issue of the image not appearing.

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