svg pattern

SVG patterns are a way to fill a shape or area with a repeated design or image. Patterns are defined using the `<pattern>` element and can contain any number of other SVG elements, such as `<rect>`, `<line>`, or even other `<pattern>` elements.

Here's an example of how to create a simple pattern in SVG:

<svg>
  <defs>
    <pattern id="checkerboard" width="20" height="20" patternUnits="userSpaceOnUse">
      <rect x="0" y="0" width="10" height="10" fill="#fff"></rect>
      <rect x="10" y="10" width="10" height="10" fill="#fff"></rect>
      <rect x="0" y="10" width="10" height="10" fill="#000"></rect>
      <rect x="10" y="0" width="10" height="10" fill="#000"></rect>
    </pattern>
  </defs>
  
  <rect x="50" y="50" width="200" height="200" fill="url(#checkerboard)"></rect>
</svg>

In this example, we define a pattern called `checkerboard` that is 20 pixels wide and 20 pixels tall (`width` and `height` attributes). We set the `patternUnits` attribute to `userSpaceOnUse` so that the pattern is scaled based on the size of the object it is applied to.

Inside the `<pattern>` element, we define four `<rect>` elements that alternate between white and black, creating a checkerboard pattern.

Finally, we apply the pattern to a `<rect>` element by setting its `fill` attribute to `"url(#checkerboard)"`.

This is just a basic example of what you can do with SVG patterns. There are many other options and attributes you can use to create more complex patterns and designs.