{"author_name":"ippa","cat":"LD #16 - Exploration - 2009","comments":[{"author_name":"sfernald","time":"December 15, 2009 11:41 am","epoch":1260895260,"text":"I liked this game so much I think I’m going to try to make my own level. Since the level code is so clean, I expect this to be quite easy. We’ll see.","spam":"N"},{"author_name":"sfernald","time":"December 15, 2009 5:41 pm","epoch":1260916860,"text":"Hey, I made a new level for your game. I has given me a chance to play around with Chingu. Must say it’s pretty cool.","spam":"N"},{"author_name":"sfernald","time":"December 17, 2009 3:52 pm","epoch":1261083120,"text":"I finished my little sequel of sorts. Here it is:","spam":"N"},{"author_name":"ippa","time":"December 18, 2009 2:50 am","epoch":1261122600,"text":"I love it :D.. you’ve made a better game then the original! Played through it, damn it was hard.","spam":"N"},{"author_name":"ippa","time":"December 18, 2009 3:33 am","epoch":1261125180,"text":"Blogpost + Windows EXE:","spam":"N"},{"author_name":"sfernald","time":"December 18, 2009 9:53 am","epoch":1261147980,"text":"Very cool.","spam":"N"}],"epoch":1260776460,"likes":0,"metadata":{"p_key":"71768","p_author":"ippa","p_authorkey":"1087","p_urlkey":"107590","p_title":"Ruby, OpenGL and Pixels","p_cat":"LD #16 - Exploration - 2009","p_event":"LD16","p_time":"1260776460","p_likes":"0","p_comments":"6","p_status":"UPD5","us_key":"1087","us_name":"ippa","us_username":"ippa","event_start":"1260489600","event_key":"2","event_name":"LD16"},"text":"

I used my favorite language of all time, Ruby<\/a>. With 1.9 Ruby has picked up speed and with Ocra<\/a> you easily make a ~1-2 meg exe-file out of it. Also the excellent (and german precision engineered)\u00a0 Gosu<\/a> enables OpenGL accelerated 2D. On top of that I used my own Ruby\/Gosu-specific framework Chingu<\/a> to get game states, re-usable game logic and a boiler plate “game object”. To get a speedy get_pixel() I used the awesome Texplay<\/a> by John Mair<\/a>.<\/p>\n

I have a pixel fetish. I love retro-looks in games, and I love pixel-perfect-collisions, a fetish that probably came into existence playing hours and hours of Lemmings 2-player mode on the classic Amiga 500.<\/p>\n

So, the most time was spent up building a good pixel-perfect-collision algo, and it came out very playable, but not perfect. I ranted about it in my last blogpost.<\/p>\n

With Ruby and Chingu my level-building got very clean, I think even ppl not into Ruby could understand what’s happening here:<\/p>\n

\n 
class Level7 < Level\n \u00a0 def setup\n \u00a0\u00a0\u00a0 self.background = \"level7.bmp\"\n \u00a0\u00a0\u00a0 every(1000) { Enemy.create(:image => \"acid_drop.bmp\", x => 150, :velocity_y => 5) }\n every(1500) { Enemy.create(:image => \"acid_drop.bmp\", x => 250, :velocity_y => 5) }\n \u00a0 end\n end<\/pre>\n <\/blockquote>\n 
or here (this is from the mainloop):<\/p>\n 
\n 
player.each_collision(Enemy) do |player, enemy|\n unless player.paused?\n player.pause!\n Sound[\"die.wav\"].play(0.3)\n after(1000) {  player.x = @entry_x; player.y = @entry_y; player.unpause!; }\n end\n end<\/pre>\n <\/blockquote>\n 
It’s nice when it’s silly simple building readable levels.<\/p>\n 
I also got a very basic and simple Map-class going so I could build on my matrix of screens that made up the game:<\/p>\n 
\n 
map = [\n [LevelUp, nil, nil, nil],\n [Level1, Level2,Level22, nil],\n [LevelAir, nil, Level3, nil],\n [LevelAir2, Level5, Level4, nil],\n [nil, Level6, Level7, nil],\n [nil, Level8, Level9, End],\n ]<\/pre>\n <\/blockquote>\n 
Basically if you exited a screen to the right I would increment a column_counter and fetch a new screen from the matrix. If exiting downwards, increment row_counter an fetch a new screen.<\/p>\n 
If you like OO, short readable code and scripting languages in general and haven’t checked out Ruby or Gosu yet, now is the time to do it.<\/p>","time":"December 14th, 2009 2:41 am","title":"Ruby, OpenGL and Pixels"}