if(): howe much time consuming it is?

[omaremad]

I though the statement was the part that the if looks at? Statements can be true or false. If is a function, it does something,it has an input and an output.

It even has its own opcode, with the statement being the input and the output being changing the state and redirecting code excution.

[arras]

It seems this thread is newer going to die
surprises myself howe lively it is

OK here are my two cents:
As much as I know even operators like + - = * / re functions in fact. I think I have it from Bruce Eckel if I remember right ...and if I am correct. Not that I feel like some authority here

[omaremad]

I agree since just look at the definition of a function from wikipedia

an abstract entity that associates an input to a corresponding output according to some rule

Im sure the guys that chose the naming conventions for thing in programming languages followed the alrady exsisting definition.

well you could think of an if statement as the if funtion with the expression inside?

[Luke]

I am updating each tile from data array everytime camera change position more than one tile. Sure I can awoid it if I would shift tiles instead of mooving them.

You could draw the tiles based on there x and y position + (or -) the camera position.

And only loop though the tiles that will be on the screen.

Eg:

Code: Select all

//This is not real code....

Tiles[100][100];

TileSize=30? ;

TilesInScreen=15 ;

CamX, CamY;

for (s32 x=CamX/TileSize -1;x<CamX/TileSize +TilesInScreen;++x) 
for (s32 y=CamY/TileSize -1;y<CamY/TileSize +TilesInScreen;++y)
{
	//(you should check the x and y values are safe)

	DrawTile(Tiles[x][y], x*TileSize +CamX, y*TileSize +CamY);
	
}

[Frodenius]

btw: sorry if i missed that, but what do you want to use instead of the if-statement ?
i think its a, no its THE fundemental thing in programming to decide wether to go on with the current string of ops or jump to another. well and how do you do it if not by testing a condition? (e.g. assembler has jnz and its.. well i dont know 1 cycle or so...)

[Warchief]

btw: sorry if i missed that, but what do you want to use instead of the if-statement ?

You can avoid using the if statement using a container without null pointers. It's not the if itself, but looping for a bunch of elements that will never meet the condition.

[arras]

Not that I am against if() I just want to know what can it's extensive use cause.

Luke >> unfortunately it is not applycable for my problem. Its easier and fasther to update all tiles once, than to check and update vissible tiles every time camera change angle or position.

[Luke]

unfortunately it is not applycable for my problem. Its easier and fasther to update all tiles once, than to check and update vissible tiles every time camera change angle or position.

So it's not a loop to draw the tiles? It's a loop to update the tiles?

Why are you updating the tiles?

[arras]

By drawing tiles one by one I would force most of the computers to standstill. I am drawing tiles in groups.

I am updating them when I change position of terrain. You may look at demo if you wan to understand why.

[messen]

Hi,

Code: Select all

cmp eax, 1

It is fast indeed.

[Luke]

By drawing tiles one by one I would force most of the computers to standstill. I am drawing tiles in groups.

I am updating them when I change position of terrain. You may look at demo if you wan to understand why.

Wait, so this is 3D tiles/terrain your talking about, sorry I though it was 2d tiles.

[arras]

Yes