1 /*

     2 * Copyright (c) 2006-2007 Nokia Corporation and/or its subsidiary(-ies). 

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:   ?Description

    15 *

    16 */

    17 

    18 

    19 

    20 #include <e32cmn.h>

    21 #include "uiacceltk/huifixmath.h"

    22 

    23 

    24 static const TInt KFixPi_2 = 0x1921F;

    25 static const TInt KSinMagic = 0x78000;

    26 

    27 #define FIX_PT_BITS 16

    28 #define SWAP(x, y) {(x)^=(y);(y)^=(x);(x)^=(y);}

    29 

    30 

    31 EXPORT_C TInt HuiFixMath::FixSin(TInt aRadians)

    32 	{

    33     if (aRadians < (-KFixPi*2) || aRadians > (KFixPi*2))

    34         {

    35         aRadians%=KFixPi*2;

    36         }

    37     

    38     if (aRadians < -KFixPi_2)

    39         {

    40         aRadians+=2*KFixPi;

    41         }

    42 

    43     // PI/2 - PI

    44     if (aRadians > KFixPi_2 && aRadians < KFixPi)

    45         {

    46         aRadians = KFixPi-aRadians;

    47         }

    48     // PI-PI*3/4

    49     else if (aRadians >=KFixPi && aRadians < (KFixPi+KFixPi_2))    

    50         {

    51         aRadians = -(aRadians-KFixPi);

    52         }

    53     // PI3*/4-2PI

    54     else if (aRadians >=(KFixPi+KFixPi_2) && aRadians <=2*KFixPi)

    55         {

    56         aRadians-=KFixPi*2;

    57         }

    58     else

    59         {

    60         // for PC lint

    61         }

    62 

    63     TInt64 value = aRadians;

    64     value = (value*value*value);

    65     value = (value / KSinMagic)>>FIX_PT_BITS;

    66     return FixMul(aRadians-value,0xF2E0);

    67 	}

    68 

    69 EXPORT_C TInt HuiFixMath::FixCos(TInt aRadians)

    70 	{

    71 	return FixSin(KFixPi_2-aRadians);

    72 	}

    73 	

    74 EXPORT_C TUint HuiFixMath::FixHypot(TInt aVal1,TInt aVal2)

    75     {

    76     TUint64 r;    

    77     TUint p = Abs(aVal1);

    78     TUint q = Abs(aVal2);

    79     if (q == 0)

    80         {

    81         return p;

    82         }

    83     if (p<q)

    84         {

    85         SWAP(p,q)

    86         }

    87     for (;;)

    88         {

    89         r = ((TUint64(q))<<FIX_PT_BITS)/p;

    90         r = (r*r) >> FIX_PT_BITS;

    91         if (r == 0)

    92             {

    93             return p;

    94             }

    95         r = (r<<FIX_PT_BITS)/(0x40000+r);

    96         p = p + 2*TUint(((r*p)>>FIX_PT_BITS));

    97         q = (TUint((q*r))) >> FIX_PT_BITS;

    98         }

    99     }