How to create function parameters

Sayagain (9)
Hi, I am having some trouble creating parameters to a function. As it stands, a header file contains the function

declaration / prototype, the main codefile(.cpp) contains the call to function and the actual function code

itself. I am trying to implement parameters into the function(which are variables from within the function code

itself.

CURRENTLY:

In header file:

void DrawSquare(COLOUR );




Call to function in mainfile:

DrawSquare(Default_Colour ); //This call to Drawsquare function is part of another function.



Function code in mainfile (situated after the previous call to function)

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void DrawSquare(COLOUR c )   //draws a square
{
	float y_start = m_iMoveY;
	float y_end = 50 + m_iMoveY;
	float x_start = 200 + m_iMoveX;
	float slope_left = -0.5;
	float x_end = 250 + m_iMoveX;
	float slope_right = 0.5;
	//Note no protection to keep in screen bounds...
	for ( int j = y_start; j <y_end; j++)
	{
		for( int i = x_start; i < x_end; i++)
		{
			Plotpix( i, j, c.r, c.g, c.b );

		}
		x_end = x_end + slope_right;
		x_start = x_start + slope_left;
		y_end = y_end + slope_right;
	}
}

AFTER MY CHANGES:


I changed the declaration in the header file to:

void DrawSquare (float x_start, float x_end, float y_start, float y_end, float slope_left, float slope_right,COLOUR );


I changed the call to the function in the mainfile to:


DrawSquare (float x_start, float x_end, float y_start, float y_end, float slope_left, float slope_right,COLOUR c );



And finally I changed the function code in the mainfile to:

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void DrawSquare (float x_start, float x_end, float y_start, float y_end, float slope_left, float slope_right,COLOUR 
c)
{
	 y_start = m_iMoveY;
	 y_end = 50 + m_iMoveY;
	 x_start = 200 + m_iMoveX;
	slope_left = -0.5;
	x_end = 250 + m_iMoveX;
	 slope_right = 0.5;
	//Note no protection to keep in screen bounds...
	for ( int j = y_start; j <y_end; j++)
	{
		for( int i = x_start; i < x_end; i++)
		{
			Plotpix( i, j, c.r, c.g, c.b );

		}
		x_end = x_end + slope_right;
		x_start = x_start + slope_left;
		y_end = y_end + slope_right;
	}
}


Can anyone seem any problems with what I did, compared to what it was before I altered the header file, call to function, and the function code itself.

Thanks a lot
//

Errors i am getting are:

1>.\MyCode.cpp(233) : error C2660: 'DrawSquare' : function does not take 0 arguments
1>.\MyCode.cpp(233) : error C2144: syntax error : 'float' should be preceded by ')'
1>.\MyCode.cpp(233) : error C2059: syntax error : ')'


all these errors are pointing to the call to function in the main .cpp file.
kempofighter (1183)
You need to show us the main function where the call is made. Post a complete example that demonstrates the problem.
Sayagain (9)
Function where call is made:
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void DrawImage( )
{
	POLYGON polyTempP, polyTempQ, polyTempQT;	// Temporary polygons for copying transformed, projected / clipped
												// versions of scene polys before drawing them. 
	int iCurrentPoly;							// Current polygon in process
	
	if ( m_iNumOfPolys <= 0 )
		 DrawSquare(float x_start, float x_end, float y_start, float y_end, float slope_left, float slope_right,COLOUR c );		// This draws the square you see, replace with Trapezium, and later Polygon
	else
		m_iOurFrameCount++;	// Increment frame counter if we have a polygon to draw


And previously it was:

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void DrawImage( )
{
	POLYGON polyTempP, polyTempQ, polyTempQT;	// Temporary polygons for copying transformed, projected / clipped
												// versions of scene polys before drawing them. 
	int iCurrentPoly;							// Current polygon in process
	
	if ( m_iNumOfPolys <= 0 )
		DrawSquare(Default_Colour );		// This draws the square you see, replace with Trapezium, and later Polygon
	else
		m_iOurFrameCount++;	// Increment frame counter if we have a polygon to draw
Zhuge (4664)
You aren't passing any parameters in the new call. It looks like you are just copying the function prototype.

You want:
func(1, 2, 3, etc);
Not:
func(float a , etc);
when you are calling the function. Look at how it was before; notice how it wasn't specifying types, just passing parameters?
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