Which is faster?

This...

GetCursorPos(&Mouse);
Colors = GetPixel(GetWindowDC(ChildWindowFromPoint(WindowFromPoint(Mouse), Mouse)), Mouse.x, Mouse.y);

Red = GetRValue(Colors);
Green = GetGValue(Colors);
Blue = GetBValue(Colors);

SetDlgItemInt(hMainDialog, ID_EDIT_RED, Red, FALSE);
SetDlgItemInt(hMainDialog, ID_EDIT_GREEN, Green, FALSE);
SetDlgItemInt(hMainDialog, ID_EDIT_BLUE, Blue, FALSE);


Or
This...

GetCursorPos(&Mouse);
Window = WindowFromPoint(Mouse);
Window = ChildWindowFromPoint(Window, Mouse);
Hdc = GetWindowDC(Window);

Colors = GetPixel(Hdc, Mouse.x, Mouse.y);

//Extract RGB values
Red = GetRValue(Colors);
Green = GetGValue(Colors);
Blue = GetBValue(Colors);

//Set the edit boxes
SetDlgItemInt(hMainDialog, ID_EDIT_RED, Red, FALSE);
SetDlgItemInt(hMainDialog, ID_EDIT_GREEN, Green, FALSE);
SetDlgItemInt(hMainDialog, ID_EDIT_BLUE, Blue, FALSE);

[HarryW]

I'd guess the first one, because it doesn't involve the three assignments for the second, third and fourth function calls. Why do you ask?

Thats what i was thinking to0, but does anyone know for sure? I want to know cuz if it is, ill start coding that way.

[HarryW]

We're talking about a difference of a few microseconds; those three assignments will boil down to maybe 10 or 20 CPU cycles. Compared to the function calls it makes a miniscule difference. I'd say stick to whatever makes your code clearer.

Besides, with compilers optimising code like they do, they might be identical once compiled anyway,

Well that code goes into the msg loop, so its called like every time. So even a few microseconds every time it loops will speed it up alot.

[HarryW]

I'm quite sure it won't. A microsecond is a millionth of a second. It depends on your CPU anyway. It's maybe 20 CPU cycles. 3 ASM instructions. How many cycles do you think a function like ChildWindowFromPoint() takes? A lot compared to an assignment.

I doubt if it makes a difference of 1% quite frankly.

[parksie]

They'll take exactly the same time, because the compiler will create temporary variables, since from an ASM point of view, you can only do it the second way.