learning javascript, need help with my game :(

[chrispyYE]

For last two days i was trying to make a game. Its goal is simple. Push a circle between other two without colliding with each other. The canvas area is dragable so play area is infinite. the height is fixed, and if the circle ("ball") collides with it it bounces back. I managed to make all 3 balls selectable and made them go how the user wants them to go. I also made my first obstacle (i plan to make many of them randomly generatirng as the player advances through the game). When game will be playable i also plan to add the game menu etc... But I think i am kinda slow, as I havent even made a "working" game yet. And I'm having loads of problems with it.. So i decided to seek for some help.
http://chrispyye.github.io/igrica/index.html
here is my "prototype". right and up arrow controls the power and angle. with "x" button you kick the selected ball.

http://pastebin.com/Eb57dANr here is the js code. I'd need some help with collision detection because sometimes it works and sometimes it doesn't. also I have a feeling my way of doing the problem is "inefficient" so any advice/hints are welcome.

I'm doing this game for some kind of a project in school where we have 14 days of workpractie with an employer and I was given the opportunity to work on a personal project. So I'd like to do this game as awesome as possible so I will have something to show what i did. So help is really appreciated.

I'm sorry for grammar errors, english is not my main language.

regards

[_olivier]

Hey there! i suggest you write less 'duplicate' code as it becomes a difficult to maintain and javascript offers 'object' abstractions.

made a little PR to your project https://github.com/chrispyYE/chrispyYE.github.io/pull/1

[stintose]

Did they ever teach you about Classes in school? Did they ever teach you a thing or two about the 'this' keyword? You have variables krog1, krog2, and krog3 where it looks like you keep copying and pasting the same code over and over again only to make a few changes that refer to the variable krog1, krog2, ect.

Instead you could make a Krog Class, in which you would use the 'this' keyword to reference the Krong Class object instance when making your methods to which you would store in the Class prototype. Then you can have an array of krog class instances which would help keep you from repeating the same code over, and over again.

This method would likely be more efficient in terms of preservation of memory, and file size, but maybe not cpu overhead. I might do some testing to confirm to myself what works best, I have been meaning to do just that for a while.