@spec render(Result.t(String.t(), binary()), :png | :svg) ::
  Result.t(String.t(), binary())

Render QR matrix to svg or png binary representation with default settings.

@spec render(
  Result.t(String.t(), binary()),
  atom(),
  QRCode.Render.SvgSettings.t() | QRCode.Render.PngSettings.t()
) :: Result.t(String.t(), binary())

Render QR matrix to svg or png binary representation with your settings.

You can change the appearance of svg using the options:

| Setting            | Type                   | Default value | Description                         |
|--------------------|------------------------|---------------|-------------------------------------|
| scale              | positive integer       | 10            | changes size of rendered QR code    |
| background_opacity | nil or 0.0 <= x <= 1.0 | nil           | sets background opacity of svg      |
| background_color   | string or {r, g, b}    | "#ffffff"     | sets background color of svg        |
| qrcode_color       | string or {r, g, b}    | "#000000"     | sets color of QR                    |
| image              | {string, size} or nil  | nil           | puts the image to the center of svg |
| structure          | :minify or :readable   | :minify       | minifies or makes readable svg file |

svg_settings = %QRCode.Render.SvgSettings{qrcode_color: {17, 170, 136}, structure: :readable}

and same a way for png:

| Setting            | Type                   | Default value | Description                  |
|--------------------|------------------------|---------------|------------------------------|
| scale              | positive integer       | 10            | changes size of rendered QR  |
| background_color   | string or {r, g, b}    | "#ffffff"     | sets background color of png |
| qrcode_color       | string or {r, g, b}    | "#000000"     | sets color of QR             |

@spec save(Result.t(any(), binary()), Path.t()) ::
  Result.t(String.t() | File.posix() | :badarg | :terminated, Path.t())

Saves rendered QR code to svg or png file. See a few examples below:

  iex> "Hello World"
        |> QRCode.create(:high)
        |> QRCode.render(:svg)
        |> QRCode.save("/path/to/hello.svg")
  {:ok, "/path/to/hello.svg"}

  iex> png_settings = %QRCode.Render.PngSettings{qrcode_color: {17, 170, 136}}
  iex> "Hello World"
        |> QRCode.create(:high)
        |> QRCode.render(:png, png_settings)
        |> QRCode.save("/tmp/to/hello.png")
  {:ok, "/path/to/hello.png"}

@spec to_base64(Result.t(String.t(), binary())) :: Result.t(String.t(), binary())

Encodes rendered QR matrix as svg or png binary into a base 64. This encoded string can be then used in Html as

For svg use

<img src="data:image/svg+xml; base64, encoded_svg_qr_code" alt="QR code" />

and in case of png

<img src="data:image/png; base64, encoded_png_qr_code" alt="QR code" />