views:

576

answers:

6

who could be faster ? and why ?

1:

Point point = new Point(25,25);   //any numbers..
Point point2 = new Point(20,95);  //any numbers..

Graphics g = CreateGraphics();
g.DrawLine(point,point2);

OR

2:

Graphics g = CreateGraphics();
g.DrawLine(new Point(25,25),new Point(20,95));
+3  A: 

Neither, there is no real difference between them except for the loss in readability (especially after a JITing).

Aaron Maenpaa
what about memory? i thought that the first one create in memory two points (objects) but the second one doesn't create in memory?is that right ????
mavric
@mavric - are created the same way -- on the stack (at least I think Point is a structure). The only difference even with reference types is that in #1, in debug mode, the Point objects won't be collected until you exit the method. In release mode, the objects will have the same lifetime.
Jonathan
A: 

2 might be faster because you're not creating intermediate pointers to the object before passing it to g.DrawLine; however, if that's the only place you use point and point2 then the compiler will likely optimize so the binary is the same anyway.

Charles Ma
+15  A: 

None of them, since both snippets will compile to the same MSIL code representation.

Besides, this is a micro-optimization, which you should avoid before actually knowing that it is the bottleneck.

arul
+2  A: 

Micro Optimization, huh? One notable playwright says code readability is more important than micro optimizations, and I agree.

Factor Mystic
+1 for playwright
TheVillageIdiot
+2  A: 

Neither is faster, the fastest one would be the one that avoids allocating those points in the Render path altogether and precreates them earlier

Paul Betts
A: 

It all depends on what else you're doing.

If you're doing almost nothing else (which I doubt) then this is the "bottleneck".

If this is the "bottleneck" then you still don't know what's dominant:

  • two "new"s and associated constructors, destructors, and garbage collection.

  • actually rendering lines.

The second is probably unavoidable, but the first is only there for style reasons.

You can find out by profiling or this simple method.

Or you can avoid the whole question with:

g.DrawLine(25,25,20,95);
Mike Dunlavey