[RaudiusParticipant]

Damn you’re right parameters are much faster than structs! A lot faster!

I even made my own test to check the speed difference for a similar implementation  to the one in my game, and primitives values are significantly faster. As I understand it this has to do with the time it takes to copy structs from one method stack to the next.

I also found that using Getters to get the primitives also significantly affects the time it takes. I assume this is also to do with copying the (“pass-by-value”) value from the one method stack to the next as opposed to just reading it directly from the class’ memory in the heap.

I may have to consider changing my game to just passing the primitives separately (instead of combining them inside a struct) since the performance impact is so much more than I anticipated.

Thanks for the heads up!

<!–more–>

Monkey

#Import "<std>" Using std.. ' Calculate distance between two coordinates Function CalculateDistance:Float(pos1:Vec2f, pos2:Vec2f) Return CalculateDistance( pos1.X, pos1.Y, pos2.X, pos2.Y ) End Function CalculateDistance:Float(x1:Float, y1:Float, x2:Float, y2:Float) Local i := x1-x2 Local j := y1-y2 Return Sqrt(i*i + j*j) End ' Entity inside the "world" has x and y fields Class Entity Field x:Float Field y:Float ' entity is given a random coordinate in the world Method New() Self.x = Rand() Self.y = Rand() End ' Get Distance from Self to another entitiy in the "world" Method DistStruct(e:Entity) CalculateDistance(Self, e) ' passing Vec2f structs with coordinates End Method DistStructGet(e:Entity) CalculateDistance(GetVec2f(), e.GetVec2f()) ' passing Vec2f structs with coordinates End Method DistPrimsGet(e:Entity) CalculateDistance(GetX(), GetY(), e.GetX(), e.GetY()) ' passing primitive coordinate values End Method DistPrims(e:Entity) CalculateDistance(x, y, e.x, e.y) ' passing primitive coordinate values End Method GetX:Float() Return x End Method GetY:Float() Return y End Method To:Vec2f() Return New Vec2f(x, y) End Method GetVec2f:Vec2f() Return New Vec2f(GetX(), GetY()) End End ' The test involves calculating distances from each entity (in an array of entitties) to every entity '>in the same array. Const n := 5000 ' size of entitiy array Function Main() Local ents:Entity[] = New Entity[n] For Local i:=0 Until n ents[i] = New Entity() End Local t := Millisecs() '' CREATE AND PASS STRUCT TO DISTANCE CALC. FUNCTION '' For Local i:=0 Until n For Local j:=0 Until n ents[i].DistStruct(ents[j]) End End Print "Time DistStruct = " + (Millisecs()-t) t = Millisecs() '' CREATE AND PASS STRUCT (created using getters) TO DISTANCE CALC. FUNCTION '' For Local i:=0 Until n For Local j:=0 Until n ents[i].DistStructGet(ents[j]) End End Print "Time DistStruct (w/ getter) = " + (Millisecs()-t) t = Millisecs() '' PASS PRIMITIVES TO DISTANCE CALC. FUNCTION '' For Local i:=0 Until n For Local j:=0 Until n ents[i].DistPrims(ents[j]) End End Print "Time DistPrims = " + (Millisecs()-t) t = Millisecs() '' PASS PRIMITIVES (from getter) TO DISTANCE CALC. FUNCTION '' For Local i:=0 Until n For Local j:=0 Until n ents[i].DistPrimsGet(ents[j]) End End Print "Time DistPrims (w/ getter) = " + (Millisecs()-t) End Function Rand:Float() Return Rnd(100) End

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#Import "<std>" Using std..   ' Calculate distance between two coordinates Function CalculateDistance:Float(pos1:Vec2f, pos2:Vec2f) Return CalculateDistance( pos1.X, pos1.Y, pos2.X, pos2.Y ) End   Function CalculateDistance:Float(x1:Float, y1:Float, x2:Float, y2:Float) Local i := x1-x2 Local j := y1-y2 Return Sqrt(i*i + j*j) End       ' Entity inside the "world" has x and y fields Class Entity Field x:Float Field y:Float ' entity is given a random coordinate in the world Method New() Self.x = Rand() Self.y = Rand() End ' Get Distance from Self to another entitiy in the "world" Method DistStruct(e:Entity) CalculateDistance(Self, e) ' passing Vec2f structs with coordinates End Method DistStructGet(e:Entity) CalculateDistance(GetVec2f(), e.GetVec2f()) ' passing Vec2f structs with coordinates End Method DistPrimsGet(e:Entity) CalculateDistance(GetX(), GetY(), e.GetX(), e.GetY()) ' passing primitive coordinate values End Method DistPrims(e:Entity) CalculateDistance(x, y, e.x, e.y) ' passing primitive coordinate values End Method GetX:Float() Return x End Method GetY:Float() Return y End Method To:Vec2f() Return New Vec2f(x, y) End Method GetVec2f:Vec2f() Return New Vec2f(GetX(), GetY()) End End     ' The test involves calculating distances from each entity (in an array of entitties) to every entity '>in the same array.   Const n := 5000 ' size of entitiy array Function Main() Local ents:Entity[] = New Entity[n] For Local i:=0 Until n ents[i] = New Entity() End     Local t := Millisecs() '' CREATE AND PASS STRUCT TO DISTANCE CALC. FUNCTION '' For Local i:=0 Until n For Local j:=0 Until n ents[i].DistStruct(ents[j]) End End Print "Time DistStruct = " + (Millisecs()-t) t = Millisecs() '' CREATE AND PASS STRUCT (created using getters) TO DISTANCE CALC. FUNCTION '' For Local i:=0 Until n For Local j:=0 Until n ents[i].DistStructGet(ents[j]) End End Print "Time DistStruct (w/ getter) = " + (Millisecs()-t) t = Millisecs() '' PASS PRIMITIVES TO DISTANCE CALC. FUNCTION '' For Local i:=0 Until n For Local j:=0 Until n ents[i].DistPrims(ents[j]) End End Print "Time DistPrims = " + (Millisecs()-t) t = Millisecs() '' PASS PRIMITIVES (from getter) TO DISTANCE CALC. FUNCTION '' For Local i:=0 Until n For Local j:=0 Until n ents[i].DistPrimsGet(ents[j]) End End Print "Time DistPrims (w/ getter) = " + (Millisecs()-t) End   Function Rand:Float() Return Rnd(100) End

[RaudiusParticipant]

I think for my specific case I’d rather be creating structs than objects since they are a one time use thing and creating objects would drastically increase the load on the GC, right?

I am just using “Rect” structs as a more convenient way to pass primitives (i.e. coordinates and dimensions for hit testing) and just wanted to make sure I am not making my game terribly inefficient in the process.

[RaudiusParticipant]

Thanks! I suppose it always pays to check the docs and forums.

So creating a struct and passing it around instead of primitives is basically the same as both the primitives and structs are “pass by value”.

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