!!!Listing 21


void MainFormUserDraw( void )
{
	UInt16 IDX;
	RectangleType Rect;

// for debugging purposes
	char *TxtBuf;
	MemHandle h;

// erase the drawing area
	RctSetRectangle( &Rect, 13, 30, 86, 110 );
	WinEraseRectangle( &Rect, 0 );
	RctSetRectangle( &Rect, 99, 40, 24, 100 );
	WinEraseRectangle( &Rect, 0 );
	for ( IDX = 0; IDX<30; IDX++ )
		WinDrawPixel( 67 + LW_DoubleToInt( LW_sin( LW_IntToDouble( IDX ) / 30.0 * 2.0 * LW_PI ) * 55.0 ) ,
			83 - LW_DoubleToInt( LW_cos( LW_IntToDouble( IDX ) / 30.0 * 2.0 * LW_PI ) * 55.0 ) );

// for debugging purposes
	h = MemHandleNew( 20 );
	TxtBuf = (char *) MemHandleLock( h );
	LW_DoubleToStr( TxtBuf, 10, Zenith.x );
	WinPaintChars( TxtBuf, StrLen( TxtBuf ), 30, 50 );
	LW_DoubleToStr( TxtBuf, 10, Zenith.y );
	WinPaintChars( TxtBuf, StrLen( TxtBuf ), 30, 62 );
	LW_DoubleToStr( TxtBuf, 10, Zenith.z );
	WinPaintChars( TxtBuf, StrLen( TxtBuf ), 30, 74 );
	LW_DoubleToStr( TxtBuf, 10, As );
	WinPaintChars( TxtBuf, StrLen( TxtBuf ), 30, 90 );
	MemHandleUnlock( h );
}
