Quil looked up in shock to see Bigelow floating high in the clouds, his balloons rustling merrily in the wind. He gruffed to her from above, "This truly is a party!". Image after image, vista after vista, passed furry Bige's wide-open eyes. A deep underlying beauty unfolded before him. A flock of bezier gulls whistled past. Beneath his dangling paws a distant shepherd called his scribbly sheep in for re-sketching. Goading him from the distance, wooden letters of so many different fonts mocked PERLIN-WOULD from the hilltops.
This truly was an amazing place. Here, dreams and reality had been drawn together - all in one Process. "_Why would I ever leave?" he barked with joy! _Why indeed!
(mix Processing Clojure)
In one hand Quil holds Processing, a carefully crafted API for making drawing and animation extremely easy to get your biscuit-loving chops around. In the other she clutches Clojure, an interlocking suite of exquisite language abstractions forged by an army of hammocks and delicately wrapped in flowing silky parens of un-braided joy.
In one swift, skilled motion, Quil throws them both high into the air. In a dusty cloud of pixels, they bond instantly and fly off into the distance painting their way with immutable trails of brilliant colour. Moments later, you see them swiftly return and hover nearby. Your very own ride to Perlinwould awaits. Summon the winds and ride well, my friend.
Quil works with Clojure 1.7, 1.8 and ClojureScript 1.9.x.
Create sample project using Quil lein template:
lein new quil hello-quil
Then go to
hello-quil/src/hello-quil/core.clj file and run it!
If you like adding libraries manually - you simply need to add Quil as a dependency to
Then to pull in all of Quil's silky goodness, just add the following to your
(:require [quil.core :as q])
For more detailed instructions head over to the wiki.
Using Quil is as easy as eating chocolate digestives. You just need to grok three basic concepts:
- The Setup fn
- The Draw fn
- The Sketch
draw are hard working artistic gladiators,
sketch is the arena in which they battle for the glory of art. However, they don't actually fight each other - they work as a team - relentlessly spilling colour all over the arena sands. The crowds roar for messy fight.
setup lays all the groundwork and is called only once at the start.
draw, on the other hand, is called immediately after
setup has completed, and then repeatedly until you summon it to stop. When you create a
sketch and name your
draw fns, the fun automatically starts.
A simple example is called for:
(ns for-the-glory-of-art (:require [quil.core :as q])) (defn setup  (q/frame-rate 1) ;; Set framerate to 1 FPS (q/background 200)) ;; Set the background colour to ;; a nice shade of grey. (defn draw  (q/stroke (q/random 255)) ;; Set the stroke colour to a random grey (q/stroke-weight (q/random 10)) ;; Set the stroke thickness randomly (q/fill (q/random 255)) ;; Set the fill colour to a random grey (let [diam (q/random 100) ;; Set the diameter to a value between 0 and 100 x (q/random (q/width)) ;; Set the x coord randomly within the sketch y (q/random (q/height))] ;; Set the y coord randomly within the sketch (q/ellipse x y diam diam))) ;; Draw a circle at x y with the correct diameter (q/defsketch example ;; Define a new sketch named example :title "Oh so many grey circles" ;; Set the title of the sketch :settings #(q/smooth 2) ;; Turn on anti-aliasing :setup setup ;; Specify the setup fn :draw draw ;; Specify the draw fn :size [323 200]) ;; You struggle to beat the golden ratio
Feast your eyes on this beauty.
sketch working in complete harmony. See how
setup turns on anti-aliasing, sets the framerate to 1 FPS and sets the background colour to a nice shade of grey.
draw then kicks into action. It chooses random stroke, fill colours as well as a random stroke weight (thickness of the pen). It then chooses some random coordinates and circle size and draws an ellipse. An ellipse with the same height and width is a circle. Finally
defsketch a convenience macro around
sketch ties everything together, specifies a title and size and starts things running. Don't just watch it though, start modifying it to see immediate effects. Go to town.
Quil supports ClojureScript! Check wiki article for more info.
When getting started with Quil, it's always useful to have the Cheatsheet handy. It may be a little bit out-dated but still contains most functions.
For up-to-date documentation please check quil.info.
If you're new to Processing and graphics programming in general, the Processing.org Learning Pages are an excellent primer and will get you started in no time.
Check Quil wiki for more documentation.
Quil supports an explorable API. For a full list of API categories and subcategories simply type
(show-cats) at the REPL.
user=> (q/show-cats) 1 Color (0) 1.1 Creating & Reading (11) 1.2 Loading & Displaying (1) 1.3 Pixels (1) 1.4 Setting (12) 2 Data (0) 2.1 Conversion (4) . . . etc
In order to see the fns within a specific category use
(show-fns 11.1) if
11.1 is the index of the category you wish to examine.
user=> (q/show-fns 11.1) 11.1 2D Primitives arc ellipse line point quad rect triangle
You can also lookup functions by name of the category or function name.
user=> (q/show-fns "trans") 14 Transform apply-matrix pop-matrix print-matrix push-matrix reset-matrix rotate rotate-x rotate-y rotate-z scale shear-x shear-y translate 14.1 Utility Macros with-translation
If you know the start of Processing API method name such as
bezier, you can use
(q/show-meths "bezier") to list all Processing API methods starting with
bezier alongside their Quil equivalents:
user=> (q/show-meths "bezier") bezierPoint() - bezier-point bezierDetail() - bezier-detail bezier() - bezier bezierTangent() - bezier-tangent bezierVertex() - bezier-vertex
Quil comes chock-packed full of examples covering most of the available API. Many of them have been translated from the excellent book "Generative Art" by Matt Pearson, with kind permission from the author.
Quil provides support for the standard Processing API - currently version
3.0.1 of Processing and
1.4.8 of Processing.js. The majority of fns Processing methods have an equivalent Quil fn. Typically,
camelCased methods have been converted to
hyphenated-versions. For a full API list (with both Processing and Quil equivalents) see API.txt.
You can ask questions, get support on our mailing list:
There is also a small number of people that hang out in
#quil on freenode. New artworks are show-cased on the @quilist Twitter account: http://twitter.com/quilist
Distributed under the Eclipse Public License either version 1.0 or (at your option) any later version.
The official Processing.org's jars, used as dependencies, are distributed under LGPL and their code can be found on http://processing.org/
See list of contributors.