anima

A Processing-style drawing and animation framework for Carp, backed by Cairo via cairo.carp. Read my blog post about the original version or browse the docs.

Dependencies

Cairo must be installed and discoverable via pkg-config:

brew install cairo        # macOS
apt install libcairo2-dev # Debian / Ubuntu

SDL2 is still used for windowing and events in defsketch.

Example

(load "anima.carp")
(use Anima)

(defn setup [cr]
  (framerate 0)) ; static sketch, draws once

(defn draw [cr]
  (do
    (stroke-color 255)
    (line cr 0.0 0.0 800.0 800.0)))

(defsketch "One line to rule them all" 800 800
  setup
  draw)

Callbacks receive a (Ptr CairoContext). Drawing coordinates are Double.

Drawing model

Anima tracks fill and stroke colors as module-level state. Each shape function builds a Cairo path and applies fill then stroke automatically, matching Processing's behavior.

(fill-color 255 0 0)       ; red fill
(stroke-color 0)            ; black stroke
(stroke-weight 2.0)
(rect cr 10.0 10.0 80.0 80.0) ; filled red, stroked black

Available shapes: line, rect, circle, ellipse, arc, triangle, point, bezier. State: fill-color, stroke-color, no-fill, no-stroke, stroke-weight, background. Transforms: push, pop, translate, rotate, scale. Text: text, text-size, text-font. Color: hsb-to-rgb.

defpicture writes a PNG directly via Cairo, no SDL window needed:

(defn render [cr]
  (do
    (background cr 255)
    (stroke-color 0)
    (line cr 10.0 10.0 190.0 190.0)))

(defpicture "MyPic" 200 200 render)

Tests

carp -x test/anima.carp