/*

    File:       DMFkey.c

    Description:Uses the Display Manager 2.0 (found in System 7.5.2 and later, or in

                the version 2.0 Display Enabler system extension which ships with

                AppleVision multisync displays) to change the monitor screen resolution

                the specified HxV resolutions.

                This FKey will flip between 640x480 and BIG.

                BIG is up to 2000x2000 if your monitor supports it.

                For information on the use of the RequestVideo sample code, please 

                refer to the    documentation found in the Display Manager Development

                Kit, or just look at the code and comments to figure it out.

    Author:     EWA

    Copyright:  Copyright: © 1996-1999 by Apple Computer, Inc.

                all rights reserved.

    Disclaimer: You may incorporate this sample code into your applications without

                restriction, though the sample code has been provided "AS IS" and the

                responsibility for its operation is 100% yours.  However, what you are

                not permitted to do is to redistribute the source as "DSC Sample 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 Code, but that you've made changes.

    Change History (most recent first):

                6/24/99 Updated for Metrowerks Codewarror Pro 2.1(KG)

                2/10/96 New today(EWA)

*/

#define minHorizontalRequest        640

#define minVerticalRequest          480

#define maxHorizontalRequest        1600

#define maxVerticalRequest          1200

#define bitDepthRequest             32

#include <Types.h>

#include <Quickdraw.h>

#include <OSUtils.h>

#include "RequestVideo.h"                   // The code that does the real work

struct INITGlobals {

    QDGlobals       initQDGlobals;          // FKEY's own private QDGlobals

    unsigned long   initQDBase;             // FKEY's global base

};

typedef struct INITGlobals INITGlobals;

main()

{

    VideoRequestRec requestRec;

    INITGlobals     qdGlobs;

    long            oldA5;

    unsigned long   theHorizontalRequest;

    unsigned long   theVerticalRequest;     

    oldA5 = SetA5((long) &qdGlobs.initQDBase);

    InitGraf((Ptr) &qdGlobs.initQDGlobals.thePort);

    theHorizontalRequest = minHorizontalRequest;

    theVerticalRequest = minVerticalRequest;

    requestRec.screenDevice = GetMainDevice ();

    requestRec.reqHorizontal = (*(*(requestRec.screenDevice))->gdPMap)->bounds.right;   // main screen is always zero offset (bounds.left == 0)

    requestRec.reqVertical = (*(*(requestRec.screenDevice))->gdPMap)->bounds.bottom;    // main screen is always zero offset (bounds.top == 0)

     if (requestRec.reqHorizontal == minHorizontalRequest || requestRec.reqVertical == minVerticalRequest)  // on a small screen now?

     {

        theHorizontalRequest    =   maxHorizontalRequest;

        theVerticalRequest      =   maxVerticalRequest;

     }

    requestRec.reqBitDepth      =   bitDepthRequest;        // bit depth request

    requestRec.reqHorizontal    =   theHorizontalRequest;   // H request

    requestRec.reqVertical      =   theVerticalRequest;     // V request

    requestRec.displayMode      =   nil;                    // must init to nil

    requestRec.depthMode        =   nil;                    // must init to nil

    requestRec.requestFlags     =   0;                      

    if (noErr == RVRequestVideoSetting(&requestRec))

    {

        RVSetVideoRequest (&requestRec);

    }

    SetA5(oldA5);

    return (noErr);

}