Windows Game Programming for Dummies (2nd Edition)/WinGamProgFD.iso/pc/Source/GPCHAP13/PROG13_2.CPP

C/C++ Source or Header | 2002-04-29 | 9.7 KB | 343 lines

// PROG13_2.CPP - Making a simple sound with DirectSound
// makes a 500hz tone, try changing it for fun!

// INCLUDES ///////////////////////////////////////////////
#define WIN32_LEAN_AND_MEAN
#define INITGUID

#include <windows.h>   // include important windows stuff
#include <windowsx.h>
#include <mmsystem.h>
#include <iostream.h> // include important C/C++ stuff
#include <conio.h>
#include <stdlib.h>
#include <malloc.h>
#include <memory.h>
#include <string.h>
#include <stdarg.h>
#include <stdio.h>
#include <math.h>
#include <io.h>
#include <fcntl.h>

#include <ddraw.h>  // directX includes
#include <dsound.h>

// DEFINES ////////////////////////////////////////////////

// directx 7+ compatibility, MS got rid of this constant, but I like it
#ifndef DSBCAPS_CTRLDEFAULT
#define DSBCAPS_CTRLDEFAULT (DSBCAPS_CTRLFREQUENCY | DSBCAPS_CTRLPAN | DSBCAPS_CTRLVOLUME )
#endif


// defines for windows
#define WINDOW_CLASS_NAME "WINXCLASS"  // class name

#define WINDOW_WIDTH  320              // size of window
#define WINDOW_HEIGHT 240
#define SCREEN_WIDTH  640              // size of screen
#define SCREEN_HEIGHT 480
#define SCREEN_BPP    8                // bits per pixel

// MACROS /////////////////////////////////////////////////

// these read the keyboard asynchronously
#define KEY_DOWN(vk_code) ((GetAsyncKeyState(vk_code) & 0x8000) ? 1 : 0)
#define KEY_UP(vk_code)   ((GetAsyncKeyState(vk_code) & 0x8000) ? 0 : 1)

// TYPES //////////////////////////////////////////////////

typedef unsigned short USHORT;
typedef unsigned short WORD;
typedef unsigned char  UCHAR;
typedef unsigned char  BYTE;

// PROTOTYPES /////////////////////////////////////////////

int Game_Init(void *parms=NULL);
int Game_Shutdown(void *parms=NULL);
int Game_Main(void *parms=NULL);

// GLOBALS ////////////////////////////////////////////////

HWND main_window_handle = NULL; // save the window handle
HINSTANCE main_instance = NULL; // save the instance
char buffer[80];                // used to print text

LPDIRECTSOUND            lpds;           // directsound interface pointer
DSBUFFERDESC            dsbd;           // directsound description
DSCAPS                  dscaps;         // directsound caps
HRESULT                 dsresult;       // general directsound result
DSBCAPS                 dsbcaps;        // directsound buffer caps

LPDIRECTSOUNDBUFFER    lpdsbprimary,    // you won't need this normally
                       lpdsbsecondary;  // the sound buffers

WAVEFORMATEX            pcmwf;          // generic waveformat structure

// FUNCTIONS //////////////////////////////////////////////

LRESULT CALLBACK WindowProc(HWND hwnd,
                            UINT msg,
                            WPARAM wparam,
                            LPARAM lparam)
{
// this is the main message handler of the system
PAINTSTRUCT    ps;           // used in WM_PAINT
HDC            hdc;       // handle to a device context

// what is the message
switch(msg)
    {
    case WM_CREATE:
        {
        // do initialization stuff here
        return(0);
        } break;

    case WM_PAINT:
         {
         // start painting
         hdc = BeginPaint(hwnd,&ps);

         // end painting
         EndPaint(hwnd,&ps);
         return(0);
        } break;

    case WM_DESTROY:
        {
        // kill the application
        PostQuitMessage(0);
        return(0);
        } break;

    default:break;

    } // end switch

// process any messages that we didn't take care of
return (DefWindowProc(hwnd, msg, wparam, lparam));

} // end WinProc

// WINMAIN ////////////////////////////////////////////////

int WINAPI WinMain(    HINSTANCE hinstance,
                    HINSTANCE hprevinstance,
                    LPSTR lpcmdline,
                    int ncmdshow)
{

WNDCLASS winclass;    // this will hold the class we create
HWND     hwnd;        // generic window handle
MSG      msg;           // generic message
HDC      hdc;       // generic dc
PAINTSTRUCT ps;     // generic paintstruct

// first fill in the window class stucture
winclass.style            = CS_DBLCLKS | CS_OWNDC |
                          CS_HREDRAW | CS_VREDRAW;
winclass.lpfnWndProc    = WindowProc;
winclass.cbClsExtra    = 0;
winclass.cbWndExtra    = 0;
winclass.hInstance     = hinstance;
winclass.hIcon         = LoadIcon(NULL, IDI_APPLICATION);
winclass.hCursor       = LoadCursor(NULL, IDC_ARROW);
winclass.hbrBackground    = (HBRUSH)GetStockObject(BLACK_BRUSH);
winclass.lpszMenuName    = NULL;
winclass.lpszClassName    = WINDOW_CLASS_NAME;

// register the window class
if (!RegisterClass(&winclass))
    return(0);

// create the window, note the use of WS_POPUP
if (!(hwnd = CreateWindow(WINDOW_CLASS_NAME, // class
                         "WinX Game Console - 500hz Tone",      // title
                          WS_OVERLAPPEDWINDOW | WS_VISIBLE,
                          0,0,     // x,y
                          WINDOW_WIDTH,  // width
                          WINDOW_HEIGHT, // height
                          NULL,    // handle to parent
                          NULL,    // handle to menu
                          hinstance,// instance
                          NULL)))       // creation parms
return(0);

// save the window handle and instance in a global
main_window_handle = hwnd;
main_instance      = hinstance;

// perform all game console specific initialization
// start up the directsound sound
Game_Init();

// enter main event loop
while(1)
    {
    if (PeekMessage(&msg,NULL,0,0,PM_REMOVE))
        {
        // test if this is a quit
        if (msg.message == WM_QUIT)
           break;

        // translate any accelerator keys
        TranslateMessage(&msg);

        // send the message to the window proc
        DispatchMessage(&msg);
        } // end if

    // main game processing goes here
    Game_Main();

    } // end while

// shutdown game and release all resources
Game_Shutdown();

// return to Windows like this
return(msg.wParam);

} // end WinMain

// WINX GAME PROGRAMMING CONSOLE FUNCTIONS ////////////////

int Game_Init(void *parms)
{
// this function is where you do all the initialization
// for your game

// this example does everything: it sets up directsound
// creates a secondary buffer, loads it with a synthesizer
// sine wave and plays it

void     *audio_ptr_1 = NULL,   // used to lock memory
        *audio_ptr_2 = NULL;

DWORD    dsbstatus;              // status of sound buffer

DWORD    audio_length_1    = 0,  // length of locked memory
        audio_length_2    = 0,
        snd_buffer_length = 64000; // working buffer

// allocate memory for buffer
UCHAR *snd_buffer_ptr = (UCHAR *)malloc(snd_buffer_length);

// we need some data for the buffer, you could load a .VOC or .WAV
// but as an example, lets synthesize the data

// fill buffer with a synthesized 500hz sine wave
for (int index=0; index < (int)snd_buffer_length; index++)
    snd_buffer_ptr[index] = 127*sin(6.28*((float)(index%22))/(float)22);

// note the math, 127 is the scale or amplitude
// 6.28 is to convert to radians
// (index % 22) read below
// we are playing at 11025 hz or 11025 cycles/sec therefore, in 1 sec
// we want 100 cycles of our synthesized sound, thus 11025/500 is approx.
// 22, thus we want the waveform to repeat each 22 clicks of index, so
// normalize to 22


// create a directsound object
if (DirectSoundCreate(NULL, &lpds, NULL)!=DS_OK )
    return(0);

// set cooperation level
if (lpds->SetCooperativeLevel(main_window_handle,DSSCL_NORMAL)!=DS_OK)
    return(0);

// set up the format data structure
memset(&pcmwf, 0, sizeof(WAVEFORMATEX));

pcmwf.wFormatTag      = WAVE_FORMAT_PCM;
pcmwf.nChannels          = 1;
pcmwf.nSamplesPerSec  = 11025;
pcmwf.nBlockAlign      = 1;
pcmwf.nAvgBytesPerSec = pcmwf.nSamplesPerSec * pcmwf.nBlockAlign;
pcmwf.wBitsPerSample  = 8;
pcmwf.cbSize          = 0;

// create the secondary buffer (no need for a primary)
memset(&dsbd,0,sizeof(DSBUFFERDESC));
dsbd.dwSize            = sizeof(DSBUFFERDESC);
dsbd.dwFlags        = DSBCAPS_CTRLDEFAULT | DSBCAPS_STATIC | DSBCAPS_LOCSOFTWARE;
dsbd.dwBufferBytes    = snd_buffer_length+1;
dsbd.lpwfxFormat    = &pcmwf;

if (lpds->CreateSoundBuffer(&dsbd,&lpdsbsecondary,NULL)!=DS_OK)
    return(0);

// copy data into sound buffer
if (lpdsbsecondary->Lock(0,
                      snd_buffer_length,
                      &audio_ptr_1,
                      &audio_length_1,
                      &audio_ptr_2,
                      &audio_length_2,
                      DSBLOCK_FROMWRITECURSOR)!=DS_OK)
  return(0);

// copy first section of circular buffer
CopyMemory(audio_ptr_1, snd_buffer_ptr, audio_length_1);

// copy last section of circular buffer
CopyMemory(audio_ptr_2, (snd_buffer_ptr+audio_length_1),audio_length_2);

// unlock the buffer
if (lpdsbsecondary->Unlock(audio_ptr_1,
                           audio_length_1,
                           audio_ptr_2,
                           audio_length_2)!=DS_OK)
    return(0);

// play the sound in looping mode
if (lpdsbsecondary->Play(0,0,DSBPLAY_LOOPING )!=DS_OK)
    return(0);

// release the memory since DirectSound has made a copy of it
free(snd_buffer_ptr);

// return success
return(1);

} // end Game_Init

///////////////////////////////////////////////////////////

int Game_Shutdown(void *parms)
{
// this function is where you shutdown your game and
// release all resources that you allocated

// release the directsoundobject
if (lpds!=NULL)
   lpds->Release();


// return success
return(1);
} // end Game_Shutdown

///////////////////////////////////////////////////////////

int Game_Main(void *parms)
{
// this is the workhorse of your game it will be called
// continuously in real-time this is like main() in C
// all the calls for you game go here!

// check of user is trying to exit
if (KEY_DOWN(VK_ESCAPE) || KEY_DOWN(VK_SPACE))
    PostMessage(main_window_handle, WM_DESTROY,0,0);

// return success
return(1);
} // end Game_Main

///////////////////////////////////////////////////////////