The R Project SVN R

/*
 *  File:       SmartScroll.c
 *
 *  Contains:   Smart Scroll API glue code
 *
 *  Copyright:  © 1996, 1997 by Marc Moini, portions by Marc Menschenfreund,
 *              Alessandro Levi Montalcini and Mark Shirley (Thanks!),
 *              misc changes for "WASTE Demo" by Marco Piovanelli.
 *              All rights reserved.
 */

#ifndef __SMARTSCROLL__
#include "SmartScroll.h"
#endif

#ifndef __GESTALT__
#include <Gestalt.h>
#endif

#ifndef __TRAPS__
#include <Traps.h>
#endif

#ifndef __OSUTILS__
#include <OSUtils.h>
#endif

#if PRAGMA_ALIGN_SUPPORTED
#pragma options align=mac68k
#endif

#if PRAGMA_IMPORT_SUPPORTED
#pragma import on
#endif

enum
{
    gestaltSmartScroll = 'MMBS'
};

enum
{
    kSetSmartScrollInfo         = 0L,
    kSetSmartScrollProp         = 1L,
    kGetSmartScrollProp         = 2L,
    kDisposeAllSmartScrolls     = 3L
};

typedef pascal void ( * SmartScrollProcPtr )
    ( SInt32 selector, SInt32 * result, ControlHandle theScrollBar, SInt32 param1, SInt32 param2 ) ;

enum
{
    uppSmartScrollProcInfo = kPascalStackBased
        | STACK_ROUTINE_PARAMETER (1, SIZE_CODE(sizeof(SInt32)))
        | STACK_ROUTINE_PARAMETER (2, SIZE_CODE(sizeof(SInt32 *)))
        | STACK_ROUTINE_PARAMETER (3, SIZE_CODE(sizeof(ControlHandle)))
        | STACK_ROUTINE_PARAMETER (4, SIZE_CODE(sizeof(SInt32)))
        | STACK_ROUTINE_PARAMETER (5, SIZE_CODE(sizeof(SInt32)))
};

#if GENERATINGCFM
    typedef UniversalProcPtr SmartScrollUPP ;
#else
    typedef SmartScrollProcPtr SmartScrollUPP ;
#endif

typedef struct
{
    char                ssPrivate [ 16 ] ;
    SmartScrollUPP      ssDispatch ;
    FourCharCode        ssSignature ;
} SmartScrollGestaltRec ;

static SmartScrollUPP sSmartScrollDispatch = nil ;

pascal void InitSmartScrollAwareApplication ( void )
{
    const SmartScrollGestaltRec * rec ;

#if ! ( GENERATINGCFM || SystemSevenOrLater )
    if ( GetOSTrapAddress ( _Gestalt ) != GetToolTrapAddress ( _Unimplemented ) )
#endif
    {
        if ( ( Gestalt ( gestaltSmartScroll, ( SInt32 * ) & rec ) == noErr ) &&
             ( rec != nil ) &&
             ( rec -> ssSignature == gestaltSmartScroll ) )
        {
            sSmartScrollDispatch = rec -> ssDispatch ;
        }
    }
}

inline SInt32 __SmartScrollDispatch
    (
        SInt32 inSelector,
        ControlHandle inControl,
        SInt32 inParam1,
        SInt32 inParam2
    )
{
    SInt32 result = 0L ;

    if ( sSmartScrollDispatch != nil )
    {
#if GENERATINGCFM
        CallUniversalProc ( sSmartScrollDispatch, uppSmartScrollProcInfo, inSelector,
                        & result, inControl, inParam1, inParam2 ) ;
#else
        sSmartScrollDispatch ( inSelector, & result, inControl, inParam1, inParam2 ) ;
#endif
    }

    return result ;
}

/****************************************************************************************/
/* Call this routine to set the Visible/Total proportion for a scrollbar. */
/*  amountVisible is a 32bit value representing the size of the portion of the document that is visible now. */
/*  amountTotal is a 32bit value representing the size of the whole document. */
/*  these two parameters must share the same unit (pixels, lines, characters, frames, etc). */

pascal void SetSmartScrollInfo
    (
        ControlHandle inScrollBar,
        SInt32 inAmountVisible,
        SInt32 inAmountTotal
    )
{
    __SmartScrollDispatch ( kSetSmartScrollInfo, inScrollBar, inAmountVisible, inAmountTotal ) ;
}

/****************************************************************************************/
/* Call this routine to set the Visible/Total proportion for a scrollbar. */
/*  proportion is a Fract value (32bit) representing the Visible/Total ratio */
/*  This call has the exact same effect as SetSmartScrollInfo, you may use either one. */

pascal void SetSmartScrollProportion
    (
        ControlHandle inScrollBar,
        Fract inProportion
    )
{
    __SmartScrollDispatch ( kSetSmartScrollProp, inScrollBar, inProportion, 0L ) ;
}

/****************************************************************************************/
/* Call this routine to get the last proportion you stored for this scrollbar. */
/* the value returned will be 0 if there is an error (Smart Scroll not installed, or no value stored)  */

pascal Fract GetSmartScrollProportion ( ControlHandle inScrollBar )
{
    return __SmartScrollDispatch ( kGetSmartScrollProp, inScrollBar, 0L, 0L ) ;
}

/****************************************************************************************/
/* Call this routine before your code Quits, to help SmartScroll */
/* free the memory it reserved for the scrollbars in your Application. */

pascal void CloseSmartScrollAwareApplication ( void )
{
    __SmartScrollDispatch ( kDisposeAllSmartScrolls, nil, 0L, 0L ) ;
}