dimension2d has a operator+, +=. and -= but no - ?

DtD · Post by **DtD** » Sat Sep 26, 2009 4:53 pm

I just noticed that irr::core::dimension2d< T > has no operator- but it does have operator-= and operator+= always has a operator+ so why no operator- ?

~DtD

vitek · Post by **vitek** » Sat Sep 26, 2009 5:09 pm

IMO, most classes that have operator X= should have the similar operator X (where X is one of the C/C++ binary arithmetic operators). There are some special cases where you might not want them all, but this is not one of them.

Travis

DtD · Post by **DtD** » Sat Sep 26, 2009 5:23 pm

I agree. Doing something like "ares->getDriver()->getScreenSize()+core::dimension2ds(-40,-40)" works but it looks off and would not work with non-signed dimensions if you ever used them.

~DtD
In case sombody is confused by my snipet, ares it my game engine and dimension2ds is just a typecase of dimension2d<s32>

Dorth · Post by **Dorth** » Sat Sep 26, 2009 5:25 pm

Especially since the standard recommends implementing one with the other...

DtD · Post by **DtD** » Mon Sep 28, 2009 10:49 pm

I made a function for operator- for dimension2d just add it after operator+ in dimension2d.h on line 99.

Code: Select all

			//! Subtract two dimensions
			dimension2d<T> operator-(const dimension2d<T>& other) const
			{
				return dimension2d<T>(Width-other.Width, Height-other.Height);
			}

~DtD