I'm searching for a high-performance game library (graphic library with collision detection). I would like to program a game, where you can place a bacteria with a left click of the mouse. If such a bacteria "meets" another bacteria, they gave birth to a new bacteria. So, logically, there will be a huge number of bacterias in a short amount of time (I plan to set a limit around 1000 - 2000 bacterias).
I tried to program it with C++, using the Clanlib library, but it wasn't really fast enough for this. The framerate actually dropped already with around 80 moving bacterias. Maybe because I chose the wrong way to do this- I created an array of sprites and each of these sprites checked for a collision with another sprite.. which isn't really a fast way for collision detection, but I couldn't think of a better way.
So my question is: What library and which programing language would be the best choice for this game? I also looking for something not too complicated to understand, since I'm still a beginner in programing.
For those which might be wondering what I want with those bacterias: In the game you could place the next higher lifeform as soon as there are enough bacterias around. This next lifeform will feed on bacterias and otherwise will work excactly like the bacterias (regarding reproduction and movements).
Both bacterias and higher lifeforms can reach a certain age: After reaching this age, they will die and disappear. The goal of the game is to get the perfect balance of bacterias and higher lifeforms. In a next stage of the game, there might be also some levels, in which a certain goal need to be reached- to make the game more interesting.