Transparency in CLJS

[mmb90]

Trying to fill a shape with alpha in clojurescript. Here’s my attempt that doesn’t work, what am I doing wrong?

(ns my.core
  (:require [quil.core :as q :include-macros true]
            [quil.middleware :as m]))


(defn setup []
  (q/frame-rate 30)
  {:graphic (q/create-graphics 500 500)})


(defn draw-state [state]
  (q/with-graphics (:graphic state)
    (q/background 240)
    ;; With the 0.5 the shape has no fill. Remove the 0.5 and it is a solid color
    (q/fill 100 140 255 0.5)
    (q/ellipse 100 100 100 100))
    (q/image (:graphic state) 0 0))


(q/defsketch my
  :host "host"
  :size [500 500]
  :setup setup
  :draw draw-state
  :middleware [m/fun-mode])

[mmb90]

Turns out the opacity is given with a range of 0-255 where I assumed it would be 0-1.0. So I don't want 0.5 I want 127. Works great.