Programming a Multiplayer FPS in DirectX/Programming a Multiplayer FPS in DirectX (Companion CD).iso/Source/Chapter 5/Engine/Engine.cpp

C/C++ Source or Header | 2005-03-29 | 12.8 KB | 399 lines

//-----------------------------------------------------------------------------
// Engine.h implementation.
// Refer to the Engine.h interface for more details.
//
// Programming a Multiplayer First Person Shooter in DirectX
// Copyright (c) 2004 Vaughan Young
//-----------------------------------------------------------------------------
#include "Engine.h"

//-----------------------------------------------------------------------------
// Globals
//-----------------------------------------------------------------------------
Engine *g_engine = NULL;

//-----------------------------------------------------------------------------
// Handles Windows messages.
//-----------------------------------------------------------------------------
LRESULT CALLBACK WindowProc( HWND wnd, UINT msg, WPARAM wparam, LPARAM lparam )
{
    switch( msg )
    {
        case WM_ACTIVATEAPP:
            g_engine->SetDeactiveFlag( !wparam );
            return 0;

        case WM_DESTROY:
            PostQuitMessage( 0 );
            return 0;

        default:
            return DefWindowProc( wnd, msg, wparam, lparam );
    }
}

//-----------------------------------------------------------------------------
// The engine class constructor.
//-----------------------------------------------------------------------------
Engine::Engine( EngineSetup *setup )
{
    // Indicate that the engine is not yet loaded.
    m_loaded = false;

    // If no setup structure was passed in, then create a default one.
    // Otehrwise, make a copy of the passed in structure.
    m_setup = new EngineSetup;
    if( setup != NULL )
        memcpy( m_setup, setup, sizeof( EngineSetup ) );

    // Store a pointer to the engine in a global variable for easy access.
    g_engine = this;

    // Prepare and register the window class.
    WNDCLASSEX wcex;
    wcex.cbSize        = sizeof( WNDCLASSEX );
    wcex.style         = CS_CLASSDC;
    wcex.lpfnWndProc   = WindowProc;
    wcex.cbClsExtra    = 0;
    wcex.cbWndExtra    = 0;
    wcex.hInstance     = m_setup->instance;
    wcex.hIcon         = LoadIcon( NULL, IDI_APPLICATION );
    wcex.hCursor       = LoadCursor( NULL, IDC_ARROW );
    wcex.hbrBackground = NULL;
    wcex.lpszMenuName  = NULL;
    wcex.lpszClassName = "WindowClass";
    wcex.hIconSm       = LoadIcon( NULL, IDI_APPLICATION );
    RegisterClassEx( &wcex );

    // Initialise the COM using multithreaded concurrency.
    CoInitializeEx( NULL, COINIT_MULTITHREADED );

    // Create the Direct3D interface.
    IDirect3D9 *d3d = Direct3DCreate9( D3D_SDK_VERSION );

    // Enumerate Direct3D device configurations on the default adapter.
    g_deviceEnumeration = new DeviceEnumeration;
    if( g_deviceEnumeration->Enumerate( d3d ) != IDOK )
    {
        SAFE_RELEASE( d3d );
        return;
    }

    // Create the window and retrieve a handle to it.
    m_window = CreateWindow( "WindowClass", m_setup->name, g_deviceEnumeration->IsWindowed() ? WS_OVERLAPPED : WS_POPUP, 0, 0, 800, 600, NULL, NULL, m_setup->instance, NULL );

    // Prepare the device presentation parameters.
    D3DPRESENT_PARAMETERS d3dpp;
    ZeroMemory( &d3dpp, sizeof( D3DPRESENT_PARAMETERS ) );
    d3dpp.BackBufferWidth = g_deviceEnumeration->GetSelectedDisplayMode()->Width;
    d3dpp.BackBufferHeight = g_deviceEnumeration->GetSelectedDisplayMode()->Height;
    d3dpp.BackBufferFormat = g_deviceEnumeration->GetSelectedDisplayMode()->Format;
    d3dpp.BackBufferCount = m_setup->totalBackBuffers;
    d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;
    d3dpp.hDeviceWindow = m_window;
    d3dpp.Windowed = g_deviceEnumeration->IsWindowed();
    d3dpp.EnableAutoDepthStencil = true;
    d3dpp.AutoDepthStencilFormat = D3DFMT_D16;
    d3dpp.FullScreen_RefreshRateInHz = g_deviceEnumeration->GetSelectedDisplayMode()->RefreshRate;
    if( g_deviceEnumeration->IsVSynced() == true )
        d3dpp.PresentationInterval = D3DPRESENT_INTERVAL_DEFAULT;
    else
        d3dpp.PresentationInterval = D3DPRESENT_INTERVAL_IMMEDIATE;

    // Destroy the device enumeration object.
    SAFE_DELETE( g_deviceEnumeration );

    // Create the Direct3D device.
    if( FAILED( d3d->CreateDevice( D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, m_window, D3DCREATE_MIXED_VERTEXPROCESSING, &d3dpp, &m_device ) ) )
        return;

    // Release the Direct3D interface as it is no longer needed.
    SAFE_RELEASE( d3d );

    // Switch lighting off by default.
    m_device->SetRenderState( D3DRS_LIGHTING, false );

    // Set the texture filters to use anisotropic texture filtering.
    m_device->SetSamplerState ( 0, D3DSAMP_MAGFILTER, D3DTEXF_ANISOTROPIC );
    m_device->SetSamplerState ( 0, D3DSAMP_MINFILTER, D3DTEXF_ANISOTROPIC );
    m_device->SetSamplerState( 0, D3DSAMP_MIPFILTER, D3DTEXF_LINEAR );

    // Set the projection matrix.
    D3DXMATRIX projMatrix;
    D3DXMatrixPerspectiveFovLH( &projMatrix, D3DX_PI / 4, (float)d3dpp.BackBufferWidth / (float)d3dpp.BackBufferHeight, 0.1f / m_setup->scale, 1000.0f / m_setup->scale );
    m_device->SetTransform( D3DTS_PROJECTION, &projMatrix );

    // Store the display mode details.
    m_displayMode.Width = d3dpp.BackBufferWidth;
    m_displayMode.Height = d3dpp.BackBufferHeight;
    m_displayMode.RefreshRate = d3dpp.FullScreen_RefreshRateInHz;
    m_displayMode.Format = d3dpp.BackBufferFormat;

    // The swap chain always starts on the first back buffer.
    m_currentBackBuffer = 0;

    // Create the sprite interface.
    D3DXCreateSprite( m_device, &m_sprite );

    // Create the linked lists of states.
    m_states = new LinkedList< State >;
    m_currentState = NULL;

    // Create the resource managers.
    m_scriptManager = new ResourceManager< Script >;

    // Create the input object.
    m_input = new Input( m_window );

    // Seed the random number generator with the current time.
    srand( timeGetTime() );

    // Allow the application to perform any state setup now.
    if( m_setup->StateSetup != NULL )
        m_setup->StateSetup();

    // The engine is fully loaded and ready to go.
    m_loaded = true;
}

//-----------------------------------------------------------------------------
// The engine class destructor.
//-----------------------------------------------------------------------------
Engine::~Engine()
{
    // Ensure the engine is loaded.
    if( m_loaded == true )
    {
        // Destroy the states linked lists.
        if( m_currentState != NULL )
            m_currentState->Close();
        SAFE_DELETE( m_states );

        // Destroy everything.
        SAFE_DELETE( m_input );
        SAFE_DELETE( m_scriptManager );

        // Release the sprite interface.
        SAFE_RELEASE( m_sprite );

        // Release the device.
        SAFE_RELEASE( m_device );
    }

    // Uninitialise the COM.
    CoUninitialize();

    // Unregister the window class.
    UnregisterClass( "WindowClass", m_setup->instance );

    // Destroy the engine setup structure.
    SAFE_DELETE( m_setup );
}

//-----------------------------------------------------------------------------
// Enters the engine into the main processing loop.
//-----------------------------------------------------------------------------
void Engine::Run()
{
    // Ensure the engine is loaded.
    if( m_loaded == true )
    {
        // Show the window.
        ShowWindow( m_window, SW_NORMAL );

        // Used to retrieve details about the viewer from the application.
        ViewerSetup viewer;

        // Enter the message loop.
        MSG msg;
        ZeroMemory( &msg, sizeof( MSG ) );
        while( msg.message != WM_QUIT )
        {
            if( PeekMessage( &msg, NULL, 0, 0, PM_REMOVE ) )
            {
                TranslateMessage( &msg );
                DispatchMessage( &msg );
            }
            else if( !m_deactive )
            {
                // Calculate the elapsed time.
                unsigned long currentTime = timeGetTime();
                static unsigned long lastTime = currentTime;
                float elapsed = ( currentTime - lastTime ) / 1000.0f;
                lastTime = currentTime;

                // Update the input object, reading the keyboard and mouse.
                m_input->Update();

                // Check if the user wants to make a forced exit.
                if( m_input->GetKeyPress( DIK_F1 ) )
                    PostQuitMessage( 0 );

                // Request the viewer from the current state, if there is one.
                if( m_currentState != NULL )
                    m_currentState->RequestViewer( &viewer );

                // Update the current state (if there is one), taking state
                // changes into account.
                m_stateChanged = false;
                if( m_currentState != NULL )
                    m_currentState->Update( elapsed );
                if( m_stateChanged == true )
                    continue;

                // Begin the scene.
                m_device->Clear( 0, NULL, viewer.viewClearFlags, 0, 1.0f, 0 );
                if( SUCCEEDED( m_device->BeginScene() ) )
                {
                    // Render the current state, if there is one.
                    if( m_currentState != NULL )
                        m_currentState->Render();

                    // End the scene and present it.
                    m_device->EndScene();
                    m_device->Present( NULL, NULL, NULL, NULL );

                    // Keep track of the index of the current back buffer.
                    if( ++m_currentBackBuffer == m_setup->totalBackBuffers + 1 )
                        m_currentBackBuffer = 0;
                }
            }
        }
    }

    // Destroy the engine.
    SAFE_DELETE( g_engine );
}

//-----------------------------------------------------------------------------
// Returns the window handle.
//-----------------------------------------------------------------------------
HWND Engine::GetWindow()
{
    return m_window;
}

//-----------------------------------------------------------------------------
// Sets the deactive flag.
//-----------------------------------------------------------------------------
void Engine::SetDeactiveFlag( bool deactive )
{
    m_deactive = deactive;
}

//-----------------------------------------------------------------------------
// Returns the scale that the engine is currently running in.
//-----------------------------------------------------------------------------
float Engine::GetScale()
{
    return m_setup->scale;
}

//-----------------------------------------------------------------------------
// Returns a pointer to the Direct3D device.
//-----------------------------------------------------------------------------
IDirect3DDevice9 *Engine::GetDevice()
{
    return m_device;
}

//-----------------------------------------------------------------------------
// Returns a pointer to the display mode of the current Direct3D device.
//-----------------------------------------------------------------------------
D3DDISPLAYMODE *Engine::GetDisplayMode()
{
    return &m_displayMode;
}

//-----------------------------------------------------------------------------
// Returns a pointer to the sprite interface.
//-----------------------------------------------------------------------------
ID3DXSprite *Engine::GetSprite()
{
    return m_sprite;
}

//-----------------------------------------------------------------------------
// Adds a state to the engine.
//-----------------------------------------------------------------------------
void Engine::AddState( State *state, bool change )
{
    m_states->Add( state );

    if( change == false )
        return;

    if( m_currentState != NULL )
        m_currentState->Close();

    m_currentState = m_states->GetLast();
    m_currentState->Load();
}

//-----------------------------------------------------------------------------
// Removes a state from the engine
//-----------------------------------------------------------------------------
void Engine::RemoveState( State *state )
{
    m_states->Remove( &state );
}

//-----------------------------------------------------------------------------
// Changes processing to the state with the specified ID.
//-----------------------------------------------------------------------------
void Engine::ChangeState( unsigned long id )
{
    // Iterate through the list of states and find the new state to change to.
    m_states->Iterate( true );
    while( m_states->Iterate() != NULL )
    {
        if( m_states->GetCurrent()->GetID() == id )
        {
            // Close the old state.
            if( m_currentState != NULL )
                m_currentState->Close();

            // Set the new current state and load it.
            m_currentState = m_states->GetCurrent();
            m_currentState->Load();

            // Swap the back buffers until the first one is in the front.
            while( m_currentBackBuffer != 0 )
            {
                m_device->Present( NULL, NULL, NULL, NULL );

                if( ++m_currentBackBuffer == m_setup->totalBackBuffers + 1 )
                    m_currentBackBuffer = 0;
            }

            // Indicate that the state has changed.
            m_stateChanged = true;

            break;
        }
    }
}

//-----------------------------------------------------------------------------
// Returns a pointer to the current state.
//-----------------------------------------------------------------------------
State *Engine::GetCurrentState()
{
    return m_currentState;
}

//-----------------------------------------------------------------------------
// Returns a pointer to the script manager.
//-----------------------------------------------------------------------------
ResourceManager< Script > *Engine::GetScriptManager()
{
    return m_scriptManager;
}

//-----------------------------------------------------------------------------
// Returns a pointer to the input object.
//-----------------------------------------------------------------------------
Input *Engine::GetInput()
{
    return m_input;
}