Cauldron2D.Easel.Drafter

This package is the atlas editor in the terminal, built on drafter. It lists the arts of a directory. It opens one on a zoomed canvas, with the palette, the tools and the frames beside it. The pointer paints, and every tool and colour has a key. The package also holds the sector map editor.

Installation

Add the dependency to mix.exs:

def deps do
  [
    {:cauldron_2d_easel_drafter, "~> 0.3", only: :dev}
  ]
end

Usage

Run the mix task on an art directory:

mix cauldron.easel priv/art --tile 16
mix cauldron.easel priv/art --tile 16 --art ship --atlas my_game

--tile is required. It is the tile size in pixels. --art opens that art at once. --atlas names the atlas that saves install into.

To start the editor from code, pass the same options as mount props:

Drafter.run(Cauldron2D.Easel.Drafter, props: %{dir: "priv/art", tile: 16, atlas: :my_game})

Each pixel is drawn as a block of cells in its colour. This works in any terminal, over ssh too. The pointer paints. Every tool, colour and frame in the side panel is a button. Press ? to see every key.

• Tools: b brush, l line, r rectangle, R filled rectangle, f fill, e eraser, i eyedropper.
• c opens the colour picker. It shows a chart of hues and greys with the palette under it. Choose with the pointer or the arrows. The colour goes under the next free key.
• o shows the frame before as onion skin. p plays the frames.
• u undoes and U redoes.
• s saves. w saves and installs the directory as the atlas named by --atlas.

A game in the same VM can subscribe to that atlas with Cauldron2D.Atlas.subscribe/1. It then redraws with the new art on its next frame.

The side panel shows the picture at actual size. It is drawn by cauldron_2d_drafter's surface widget, the same way a game draws it. A terminal with graphics (kitty, sixel, iTerm2) shows the picture, animated at its rate. Other terminals show its glyph. Press m to tile the picture, to check one that repeats. Press g to set the glyph and colour the text renderer draws.

On the arts screen, press D to derive an art from the one chosen. You type a line that Linocut.Derive reads, such as name = from ART; colour K #rrggbb; flip h; over HAT 0 -2. The line is kept in atlas.txt. The derived art is rebuilt from the drawing every time the atlas loads. Press y to clone an art into a picture of its own.

This is a pixel-art tool. A picture has a palette of up to ninety colours and a grid of keys. That is what .pic holds and what every renderer draws. A .png with more colours is refused on load. It is not quantised.

The widgets

Cauldron2D.Easel.Drafter.Canvas is the canvas widget. Any drafter application can use it. Call Cauldron2D.Easel.Drafter.register_widgets/0 first, then add:

{:easel_canvas, [id: :canvas, easel: easel, zoom: 4, onion: false, on_paint: :paint, flex: 1]}

A press or a drag sends the application {:paint, %{x: x, y: y, phase: :start | :drag | :end}}.

Cauldron2D.Easel.Drafter.Swatches is the colour chart widget, :easel_swatches. Cauldron2D.Easel.Drafter.ActualSize installs the picture being edited as an atlas with one art. A Cauldron2D.Drafter.Surface then draws it.

The sector editor

Run mix cauldron.sectors on a sector document. It opens Cauldron2D.Easel.Drafter.SectorEditor. If the file does not exist, the first save creates it.

mix cauldron.sectors priv/maps/hall.json
mix cauldron.sectors priv/maps/hall.json --grid 16

--grid sets the snap for a new document, in world units. The default is 32.

The document is a Cauldron2D.Easel.Sectors map. You draw rooms as polygons on a grid. Rooms that share an edge are joined. Each room and wall has its own heights, pictures and light. Edits can be undone. The plan from above is Cauldron2D.Easel.Drafter.Plan. Beside it, Cauldron2D.Sectors.View draws a first-person view. It uses Cauldron2D.Easel.SectorArt's pictures, or the game's own pictures when you pass them as the :art prop.

The keys:

• m switches between drawing and choosing.
• Drawing: press on the plan to add a corner. Enter closes the room. Backspace takes back a corner. Esc drops the room.
• Choosing: press on a room to pick it. The eye stands in that room.
• With a room picked: f/F lower or raise the floor, c/C the ceiling. [/] change the light. t sets the floor's picture, T the ceiling's and w the walls'. x removes the room.
• The eye: i/k move forward and back. j/l turn.
• The plan: arrows pan. +/- zoom.
• u undoes, U redoes, s saves, ^Q quits.

How it fits

The document and the art directory come from cauldron_2d_easel. This package draws them with drafter and cauldron_2d_drafter. The same editor runs in a browser with cauldron_2d_easel_web, and in Livebook with cauldron_2d_easel_kino.

License

MIT