Okay, can I ask exactly how you produce the map ? In my situation I know how to compute whether a cell [i,j] is blocked, I can generate the list of couples [i,j] that suits me ... and then I am stuck, not knowing with function / macro to call. I guess it's just the same problem as with cond, I am pretty sure their is a function that does just that, but I don't have a clue how it's called ;) what I am looking for is :
foobar [f col] "Returns a map of the elements of col to the evaluation of function f on each of them" For some value of foobar ... I tried google all functions starting with "Returns a map", but I had no luck .... it is some usage of map ? of assoc itself in a way that I haven't tried ? Cheers PH On 9 fév, 17:57, Matt Clark <matt.clar...@gmail.com> wrote: > I agree with what Laurent said about clojuredev, I've been having > great success using it myself, for my clojure/slickcreations. My > first project was converting Kevin Glass's platformer example over to > clojure which gave me a chance to learnslickand Clojure all in one > go! Unfortunately, the code I wrote for that is getting to be quite > out of date now and probably doesn't work with the latest clojure, but > I can at least offer some input based on my experience. > > The platformer example is based on a tile grid with some fancy phys2d > stuff thrown in for collision detection. For grid storage I started > with a vector of vectors, and like you, which I too found far too > cumbersome. So I ditched it and decided to go with a sorted map of > coordinates to tiles (from the suggestion made in your linked thread > actually). Although I'm still not sure this is going to be a "best > practice" in clojure grids, it worked really well for me, simplifying > access to grid immensely. In your code, moving over to a map would > probably reduce the number of functions involved in your matrix > generation phase. > > Also, in order to reduce passing around refs to collections for all > the functions, I declared things like the player and the screen in the > game's namespace and then later defined them during the game's init > stage. Still not completely ok with that solution, but I think it's > OK within the context of aslickgame. > > For me the import count reduced as the game grew and I separated it > into various files, so I wouldn't worry about that too much. > Personally, I've always been a fan of explicit imports so I know > what's going on when I reference a class name :) > > -Matt > > On Feb 9, 9:14 am, phtrivier <phtriv...@gmail.com> wrote: > > > Hi everyone > > > first of all, this is my first post, so if I ask FAQs or deserve to > > RTFM, please tell me. > > > I am learning clojure, and trying to adapt some game code written in a > > Java framework calledSlick. After a couple of beginner's mistake (the > > kind you do to learn ;) ), I got a working convestion of a Scoller > > example. Still, there are some things that I don't find very elegant, > > or where I'm pretty sure to be reinventing some wheel. > > > Code is here : > > >http://tinyurl.com/dj4l9z > > or > > git://github.com/phtrivier/clj-slick-tank.git > > > * The game is tile-based. I need to build up a collision map ("can the > > tank walk on cell [3,2] ?"). Java does it with a two-dimensional array > > of booleans. From discussion here > > :http://groups.google.com/group/clojure/browse_thread/thread/5eb78c620... > > , I choosed to use a vector of vector (i probably should'nt have, but > > that's another point). I wrote this : > > > (defn blocked? > > "Is a position blocked in the screen?" > > [screen x y] > > (let [i (int x) > > j (int y)] > > (true? (get (get (screen :blocked) i) j)))) > > > (defn make-row-generator > > [cell-generator w] > > (fn [i] > > (vec (map (fn [j] (cell-generator i j)) > > (range 0 w))))) > > > (defn make-matrix > > [w h cell-generator] > > (vec (map (make-row-generator cell-generator w) > > (range 0 h)))) > > > (defn make-collision-map > > "Builds a double dimensioned array telling > > whether a cell is blocked" > > [m w h] > > (make-matrix > > w h > > (fn [i j] > > (let [tileId (.getTileId m i j 0)] > > (let [res > > (Boolean/parseBoolean > > (.getTileProperty m tileId "blocked" "false"))] > > res > > ))))) > > > (the 'm' is aslick-specific stucture that holds the tile map). > > Am I duplicating some existing library to build matrices ? Is there a > > cleaner way to do it ? > > > * In a method I check for collisions : > > > ;; Movement > > (defn try-move > > "Try and move a player in the screen given a direction. > > Returns a list with the moved player, and a > > boolean indicating whether the move was successfull. > > " > > [player screen dx dy] > > (let [new_x (+ (player :x) dx) > > new_y (+ (player :y) dy)] > > > (let [bxy (blocked? screen new_x new_y) > > bx (blocked? screen new_x (player :y)) > > by (blocked? screen (player :x) new_y)] > > (if bxy > > (if bx > > (if by > > [player, false] > > [(assoc player :y new_y), true]) > > [(assoc player :x new_x), true]) > > [(assoc player :x new_x :y new_y), true])))) > > > Will i get used to the nested 'if' blocks someday ? Any way to write > > the equivalent of a switch case here, if only to improve > > readibility ? > > > * Finally, my code starts with a rather ugly > > > (ns tank > > (:import (org.newdawn.slickAnimation > > AppGameContainer > > BasicGame > > GameContainer > > Graphics > > Input > > SlickException > > SpriteSheet) > > (org.newdawn.slick.tiled TiledMap) > > (org.newdawn.slick.util Log))) > > > I know there is no way to import org.newdawn.slick.* (as discussed > > here > > :http://groups.google.com/group/clojure/browse_thread/thread/fa00a0ff4... > > ). What do you do in programs that need huge list of imports ? I'm > > kinda spoiled by the Eclipse way of doing this, which is roughly : > > import everything, forget about it, and let you IDE clear up the list. > > And at least for development part it make things easier. If I hadn't > > had the exact list of import to copy paste in this case, I would > > probably have gone bored and depressed by the second class to import > > manually (lazyness is not only for evaluation ;) ) > > > Thanks for any ideas, sorry if post is too long / newbie-like. > > > Cheers > > PH --~--~---------~--~----~------------~-------~--~----~ 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 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 -~----------~----~----~----~------~----~------~--~---
