Thank you both for your suggestions, they are really helpful. I was
able to optimise my code quite a bit.
My collision detection is pretty primitive, so I'll definitely try to
improve that.
public boolean detectCollision(Point target, int dist)
{
return (Math.abs(this.x - target.x)<=dist && Math.abs(this.y -
target.y)<=dist);
}
@Danie, you mentioned that I should split the drawing form the
animation code; What are the benefits of doing this? as both drawing
and moving are driven by the same loop?
On May 24, 8:33 am, Daniel Drozdzewski <[email protected]>
wrote:
> Stuart,
>
> There are few fixes straight away:
>
> - Have a predefined Paint object for your dots and use that instead
> of creating new Paint object each time you enter drawDots()
> - assign dots.size() to a local variable and keep testing that
> variable in the for loop, rather than calling size() method with each
> operation
> - don't detect collisions in your drawing code
> - worth testing whether Canvas.drawBitmap() (cached bitmap of a dot)
> could be quicker than Canvas.drawCircle(); first one only copies
> memory byte by byte, while second does some computation too
> - and finally as String said: profile it
>
> Then you have to think:
> - how complex is your collision detection? it has to be optimised and
> you should not be iterating through all dots testing for potential
> collision with PacMan; if you think about it, your dots don't move and
> PacMan moves incrementally; there are few clever strategies that you
> could use; in general collision detection optimisation strategies are
> not trivial, but I am sure you could find something that would work
> well for you and would not be too hard to implement;
>
> have a look here as an entry to possible
> ideas:http://en.wikipedia.org/wiki/Collision_detection
>
>
>
>
>
>
>
>
>
> On Tue, May 24, 2011 at 12:57 PM, neuromit <[email protected]> wrote:
> > I'm writing a pacman style game that has a lot of things to be drawn,
> > namely, the dots that pacman likes to eat.
>
> > I'm finding that the drawing of the dots is greatly hampering the
> > performance of the game. If I turn them off my app consumes much fewer
> > cpu cycles than if they are left on.
>
> > here is the code i'm using to draw the dots:http://paste2.org/p/1432169
>
> > void drawDots(Canvas c) {
> > if (!this.drawDots)
> > return;
>
> > Paint p = new Paint(mPaint);
> > p.setColor(this.dotColor);
> > for (int i=0; i<dots.size(); i++)
> > {
> > Dot d = dots.get(i);
> > if (this.pacdroid.detectCollision(d))
> > d.disableDot();
> > if (d.enabled)
> > c.drawCircle(d.x, d.y,d.r, p);
> > //dots.get(i).draw(c, p);
> > }
> > }
>
> > --
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>
> --
> Daniel Drozdzewski
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