Posts by daviddoria

beautiful! thanks!

beautiful! thanks!

you nailed it... sorry for the stupid question.

I have "right" overloading working fine with:

Vector Point::operator*( double P )

this would be called with MyPoint*2 and gives the results I would like. However, if I say:

2*MyPoint, it says I can't do that. Makes sense, but surely this can be done! I had trouble googling because I didn't know what to call this!

Any help will be appreciated!

Dave

I have a class called Point.

Point.h :

#ifndef POINT_H
#define POINT_H

#include "Vector.h"
#include <iostream>

class Point
{
	friend ostream& operator<<(ostream& output, const Point& p) //must have global scope
	{
		output << "x: " << x << " y: " << y;
		return output;
	}

The compiler is telling me
syntax error: Missing ';' before '&'

Am I doing something wrong?

Thanks!

Dave

What I was saying was the compiler did not complain that I did NOT have #ifndef - shouldn't it have?
Other than that I think I'm good to go!

So basically all that is different is you put the functions in a cpp file?

I replaced

Point Vector::GetPoint()

with

Point GetPoint()

is that not a good idea?

Also, you include the headers in the Vector.cpp and Point.cpp AND in program.cpp - doesn't that mean you need to have #ifndef statements?

Thanks for the help!

I have a class Vector that needs to have a function that returns type Point, and a class Point that needs to have a function that returns type Vector.

I was informed that I needed to use forward references, which I thought I had implemented as follows. I am still getting this error: use of undefined type 'Vector'

Here are my files:

Point.h

class Vector;

class Point
{

public:
	Vector GetVector()
	{
		Vector A;
		return A;
	}
};

Vector.h

class Point;

class Vector
{

public:
	Point GetPoint()
	{
		Point A;
		return A;
	}
};

Program.cpp

#include <iostream>

#include "Point.h"
#include "Vector.h"

using namespace std;

void main()
{
	Point P;
	Vector V;
}

Surely this is a very easy problem and I am just doing something silly. Please let me know.

Thanks!

Dave

well apparently not EVERYone because it doesn't let me do what I want...

Is it possible to make a function with an unknown number of parameters without knowing ANY of them?

ie.
void Test(...)

I know you could do
void Test(va_alist)
with varargs.h, doesn't make sense that this functionality has been removed does it?

Thanks!

Dave

but how do you make the color transitions smooth - ie. how to ensure the colors run through the reds first before switching to the mix of red green before switching to the green... etc. ?

ie the colors dont go in order like some sort of binary thing. 0 0 0 is not necessarily followed by 0 0 1, etc.

Am I wrong about this?

Thanks,

Dave

Is there a way to interpolate between RGB values? I have a set of values that I want to map (linearly or otherwise) to colors from a color_min RGB triple to a color_max RGB triple. Since RGB is not "incrementable", how would I do this?

Thanks,

David