Canvas

API

clear_canvas/0

@spec clear_canvas() :: :ok

Used to erase all the drawings and leave an empy canvas.

draw_rectangle/1

@spec draw_rectangle(map) :: {:ok, Rectangle.t()} | {:error, Ecto.Changeset.t()}

It create and store a new Rectangle in the DB which will be rendered on the next page load.

Attributes

• x :integer, the horizontal position of the top right corner of the rectangle, Required
• y :integer, the vertical position of the top right corner of the rectangle, Required
• width :integer, the width of the rectangle, Required
• height :integer, the height of the rectangle, Required
• fill_char :string, the character to fill the rectangle with
• outline_char :string, the character to draw the outline of the rectangle

Note: Either fill_char or outline_char should be specifyed.

## Examples

  iex> Canvas.draw_rectangle(%{x: 2, y: 0, width: 3, height: 5, fill_char: ".", outline_char: "X"})

Sample Usage

To generate the next canvas follow the next steps:

1. Start the server in interactive mode iex -S mix phx.server
2. visit localhost:4000 to see an empty canvas
3. to create the first Rectangles go back to the terminal and run the following commands.

iex> Canvas.draw_rectangle(%{x: 0, y: 10, width: 8, height: 4, outline_char: "O"})
{:ok, %Canvas.Rectangles.Rectangle{ ... }}

iex> Canvas.draw_rectangle(%{x: 5, y: 12, width: 5, height: 3, fill_char: "X", outline_char: "X" })   
{:ok, %Canvas.Rectangles.Rectangle{ ... }}

iex> Canvas.draw_rectangle(%{x: 15, y: 3, width: 7, height: 6, fill_char: "." })                    
{:ok, %Canvas.Rectangles.Rectangle{ ... }}

4. reload the page and the Rectangles should be rendered in the canvas.

Docs

To generate the API documentation files:

> mix deps.get
...

> mix docs

Later you can acces to your doc/Canvas.html