void	InitToolbox	( void );
void	InitWindow	( void );
void	Line2		( short, short, short, short, short );
void	main		( void );

Ptr		baseAddr;
short	rowBytes;

void	InitToolbox	( void )
{
	InitGraf ( &qd.thePort );
	InitFonts ();
	InitWindows ();
	InitMenus ();
	InitCursor ();
}

void	InitWindow ( void )
{
	WindowPtr	window;
	Rect		windowRect = { 0, 0, 480, 640 };
	
	window = NewCWindow ( nil, &windowRect, "\p", true, 0, (WindowPtr)-1L, false, 0L );
	ShowWindow ( window );
	SetPort ( window );
}

void	Line2	( short x1, short y1, short x2, short y2, short color )
{
	double	curX, curY, deltaDot, colorIndex;
	short	drawX, drawY, curColor;
//	short	temp;
	
	if (( x1 == x2 ) || ( y1 == y2 ) || (( x2 - x1 ) & 0x7FFF) == (( y2 - y1 ) & 0x7FFF ))
	{
		MoveTo ( x1, y1 );
		LineTo ( x2, y2 );
		return;
	}
	
	deltaDot = (float)( y2 - y1 ) / (float)( x2 - x1 );
	curX = x1;
	curY = y1;
	colorIndex = 0;
	
	if ( deltaDot < 1 && deltaDot > -1 )
	{
		for ( curX = x1; curX < x2; ++curX )
		{
			curColor = 10 * ( colorIndex >= 0 ? colorIndex : -colorIndex );
			
			drawX = curX;
			drawY = curY;
			
			if ( drawX >= 0 && drawX < 640 && drawY >= 0 && drawY < 480 )
				baseAddr [ rowBytes * drawY + drawX ] = color - curColor;
			if ( colorIndex > 0 )
			{
				if ( drawX >= 0 && drawX < 640 && ( drawY + 1 ) >= 0 && ( drawY + 1 ) < 480 )
					baseAddr [ rowBytes * ( drawY + 1 ) + drawX ] = color - 10 + curColor;
			}
			else if ( colorIndex < 0 )
			{
				if ( drawX >= 0 && drawX < 640 && ( drawY - 1 ) >= 0 && ( drawY - 1 ) < 480 )
					baseAddr [ rowBytes * ( drawY - 1 ) + drawX ] = color - 10 + curColor;
			}
			
			curY += deltaDot;
			
			colorIndex += deltaDot;
			if ( colorIndex >= 1 )
				colorIndex--;
			else if ( colorIndex <= -1 )
				colorIndex++;
		}
	}
	else
	{
		deltaDot = (float)(( x2 - x1 ) & 0x7FFF ) / (float)( y2 - y1 );
		for ( curY = y1; curY < y2; ++curY )
		{
			curColor = 10 * ( colorIndex >= 0 ? colorIndex : -colorIndex );
			
			drawX = curX;
			drawY = curY;
			
			if ( drawX >= 0 && drawX < 640 && drawY >= 0 && drawY < 480 )
				baseAddr [ rowBytes * drawY + drawX ] = color - curColor;
			if ( colorIndex > 0 )
			{
				if (( drawX + 1 ) >= 0 && ( drawX + 1 ) < 640 && drawY >= 0 && drawY < 480 )
					baseAddr [ rowBytes * drawY + drawX + 1 ] = color - 10 + curColor;
			}
			else if ( colorIndex < 0 )
			{
				if (( drawX + 1 ) >= 0 && ( drawX + 1 ) < 640 && drawY >= 0 && drawY < 480 )
					baseAddr [ rowBytes * drawY + drawX + 1 ] = color - 10 + curColor;
			}
			
			curX += deltaDot;
			
			colorIndex += deltaDot;
			if ( colorIndex >= 1 )
				colorIndex--;
			else if ( colorIndex <= -1 )
				colorIndex++;
		}
	}
}

void	main	( void )
{
	InitToolbox ();
	InitWindow ();
	
	baseAddr = GetPixBaseAddr((**GetMainDevice()).gdPMap);
	rowBytes = (**(**GetMainDevice()).gdPMap).rowBytes & 0x3FFF;
	
	MoveTo ( 10, 470 );
	TextSize ( 48 );
	DrawString ( "\pAnti-Aliased Lines" );
	
	Line2 ( 0, 0, 640, 480, 255 );
	
	while ( !Button ())
	{
		WaitNextEvent ( everyEvent, nil, 0L, 0L );
	}
	FlushEvents ( everyEvent, 0 );
}