/*

    File:       OldBitMap.c

    Contains:   old-style bitmap utility routines for allocating, de-allocating, and masking.

    Written by:     

    Copyright:  Copyright © 1992-1999 by Apple Computer, Inc., All Rights Reserved.

                You may incorporate this Apple sample source code into your program(s) without

                restriction. This Apple sample source code has been provided "AS IS" and the

                responsibility for its operation is yours. You are not permitted to redistribute

                this Apple sample source code as "Apple sample source code" after having made

                changes. If you're going to re-distribute the source, we require that you make

                it clear in the source that the code was descended from Apple sample source

                code, but that you've made changes.

    Change History (most recent first):

                7/9/1999    Karl Groethe    Updated for Metrowerks Codewarror Pro 2.1

*/

#include "OldBitMap.h"

#include <Quickdraw.h>

#include <Memory.h>

void FreeBitMap(BitMap *Bits)

/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    Dumps a BitMap created by NewBitMap below.

  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/

{

    DisposePtr(Bits->baseAddr);

    Bits->baseAddr=nil;

    SetRect(&Bits->bounds,0,0,0,0);

    Bits->rowBytes=0;

}

void CalcOffScreen(register Rect *frame,register long *needed, register short *rows)

/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    Calculates how much memory and rowbytes a bitmap of the size frame would require.

  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/

{

    *rows=((((frame->right) - (frame->left)) + 15)/16) *2;

    *needed=(((long)(*rows)) * (long)((frame->bottom) - (frame->top)));

}

void NewBitMap(Rect *frame,BitMap *theMap)

/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    Creates a new empty bitmap.

  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/

{

    Size    size;

    short   rbytes;

    CalcOffScreen(frame,&size,&rbytes);

    theMap->rowBytes=rbytes;

    theMap->bounds=*frame;

    theMap->baseAddr=NewPtrClear(size);

}

void NewMaskedBitMap(BitMap *srcBits, BitMap *maskBits, Rect *srcRect)

/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    Pass a pointer to an existing bitmap, and this creates a bitmap that is an

    equivelent mask.

  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/

{

    short   rowbytes,height,words;

    long    needed;

    NewBitMap(srcRect,maskBits);

    if(MemError())      

    {

        maskBits->baseAddr=nil;

        SetRect(&maskBits->bounds,0,0,0,0);

        maskBits->rowBytes=0;

     }

     else       /*  memory was allocated for Mask BitMap ok */

     {

        CalcOffScreen(srcRect,&needed,&rowbytes);

        words=rowbytes/2;

        height=srcRect->bottom - srcRect->top;

        CalcMask(srcBits->baseAddr,maskBits->baseAddr,rowbytes,rowbytes,height,words);

     }

}