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Re: Should RGBA have got 4 arguments constructor? [message #43395 is a reply to message #43179]

Thu, 24 July 2014 22:32

Klugier
Messages: 1099
Registered: September 2012
Location: Poland, Kraków

Senior Contributor

Hello Mirek,

We can easily implement RGBA constructor in C++11 branch... This standard changes a little bit POD rules. Now we can define constructor, but firstly we need to tell compiler that default constructor exists. I enclose demonstrative code:

#include <Core/Core.h>

#include <type_traits>

using namespace Upp;

namespace UppCpp11 {
struct RGBA {
	RGBA() = default;
	RGBA(byte r, byte g, byte b, byte a) {
		this->r = r;
		this->g = g;
		this->b = b;
		this->a = a;
	}
	
	byte b, g, r, a;
};

struct NotPodRGBA {
	NotPodRGBA(byte r, byte g, byte b, byte a) {
		this->r = r;
		this->g = g;
		this->b = b;
		this->a = a;
	}
	
	byte b, g, r, a;
};
}

CONSOLE_APP_MAIN
{
	UppCpp11::RGBA color(255, 255, 255, 255);
	Cout() << "Is RGBA POD? " << (std::is_pod<UppCpp11::RGBA>::value ? "True" : "False") << "!\n";
	Cout() << "Is NotPodRGBA POD? " << (std::is_pod<UppCpp11::NotPodRGBA>::value ? "True" : "False") << "!\n";
}

Result:

Is RGBA POD? True!
Is NotPodRGBA POD? False!

More information you can find on: http://stackoverflow.com/questions/4178175/what-are-aggregat es-and-pods-and-how-why-are-they-special/7189821#7189821 - second answer.

P.S.
Tested with g++ 4.8 using std=c++11 flag.

Sincerely,
Klugier

U++ - one framework to rule them all.

[Updated on: Thu, 24 July 2014 22:35]

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