On Sep 15, 2010, at 1:57 PM, Alan wrote: > This looks a lot like what I would do - I'm afraid I don't have any > brilliant insights for you. I do have a couple ways you could make > this smaller, though: > > - Instead of (atom ()) and convoluted swap! logic, what about (atom > []) and (swap! shapes conj new-shape)? > - Similarly don't use (list shape-name...), try [shape-name...] > -- (defn render-shape [shape-name [x y w h] color]) > -- (render-shape 'rect (take 4 (repeatedly #(rand-int 400))) blue) > > The last two combine to let you avoid writing rand-int so many times.
Thanks Alan. Using vectors instead of lists does clean things up a little. I've spent a lot of my life in other Lisps and so lists spring to mind first. FYI below is a slightly nicer version that uses vectors and also adds line drawing. I didn't follow your other suggestions because I was interested in minimizing the tool, not the example. I'd still be quite interested in any advise anyone has on minimizing the code for initializing/buffering the window (using only core, contrib, and built-in java libraries -- but maybe different built-in java libraries? I'm coming from Lisp, not from Java, and I'm not sure what's in there.) Also, this would have a smaller impact but I'm curious about it: is there a way to treat method names as data and then make calls to them, as one can with clojure functions? Then I could pass things like fillRect, or map rect to fillRect, etc. This would make things slightly simpler here but be handy in other cases... but I don't see how to do it. Thanks, -Lee -------------- (def max-x 500) (def max-y 500) (def shapes (atom [])) (defn render-shape [graphics [shape-name x y w h r g b a]] (.setColor graphics (java.awt.Color. r g b a)) (case shape-name rect (.fillRect graphics x y w h) oval (.fillOval graphics x y w h) line (.drawLine graphics x y w h))) (def panel (let [jp (proxy [javax.swing.JPanel] [] (getPreferredSize [] (java.awt.Dimension. max-x max-y)) (paint [g] (render-shape g ['rect 0 0 max-x max-y 255 255 255 255]) (doall (map #(render-shape g %) @shapes))))] (doto (new javax.swing.JFrame "My graphics window") (.setSize max-x max-y) (.add jp) (.setVisible true)) jp)) (defn draw-shape [& shape] "Adds a shape to the current drawing. The first argument should be one of the following symbols: rect, oval, or line. For rect or oval this should be followed by: x, y, width, height, red, green, blue, alpha. The x and y coordinates specify the upper right corner. Color values (including alpha, which is opacity) should range from 0 to 255. For line the arguments are the remaining arguments are x-start, y-start, x-end, y-end, red, green, blue, alpha." (swap! shapes conj shape) (.paint panel (.getGraphics panel))) ;; test it out by drawing a bunch of shapes (draw-shape 'rect 20 20 460 80 255 128 0 255) (draw-shape 'oval 120 120 300 100 100 100 0 20) (draw-shape 'oval 300 50 100 300 10 100 200 20) (draw-shape 'line 0 0 500 500 255 0 0 255) -- Lee Spector, Professor of Computer Science School of Cognitive Science, Hampshire College 893 West Street, Amherst, MA 01002-3359 lspec...@hampshire.edu, http://hampshire.edu/lspector/ Phone: 413-559-5352, Fax: 413-559-5438 Check out Genetic Programming and Evolvable Machines: http://www.springer.com/10710 - http://gpemjournal.blogspot.com/ -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en