操作和慣性範例

發行項
06/13/2023

操作和慣性範例示範如何將 Windows Touch 支援新增至使用 Windows Touch API 的原生 Windows 應用程式。此範例會實作 API 的基本功能，以啟用物件的轉譯、旋轉和縮放，以及對其套用慣性屬性。此範例也會示範如何為您的 Windows Touch 應用程式提供基本的滑鼠支援。下圖顯示範例在執行時的外觀。

螢幕擷取畫面，顯示操作和慣性範例中具有漸層的兩個方塊

當使用者從支援 Windows Touch 的電腦執行應用程式時，可以獨立操作具有漸層的方塊。

註冊觸控視窗

在接收觸控輸入之前，您必須先呼叫下列函式，通知系統您的應用程式是 Windows Touch 應用程式：

   RegisterTouchWindow(g_hWnd, 0);

實作 _IManipulationEventSink 介面

_IManipulationEvents事件接收包含三個函式：ManipulationStarted、ManipulationDelta和ManipulationCompleted。 IManipulationProcessor介面和IInertiaProcessor介面會使用這些回呼函式來傳回處理器叫用ProcessTime、ProcessUpWithTime、ProcessDownWithTime和ProcessMoveWithTime函式之後所計算的值。下列程式碼範例示範 _IManipulationEvents 介面的範例實作。

#include "cmanipulationeventsink.h"
#include <math.h>

CManipulationEventSink::CManipulationEventSink(HWND hWnd, CDrawingObject *dObj, int iTimerId, BOOL inertia) {
    // Manipulation & Inertia Processors
    m_manip = NULL;
    m_inert = NULL;

    // Connection points for COM.
    m_pConPointContainer = NULL;
    m_pConnPoint = NULL;

    // Reference to an object associated with this event sink.
    m_dObj = dObj;

    // Handle to the window used for computing boundaries.
    m_hWnd = hWnd;

    // The unique timer id for this manipulation event sink.
    m_iTimerId = iTimerId;

    m_bInertia = inertia;

    m_cRefCount = 1;
}


CManipulationEventSink::~CManipulationEventSink()
{

}


HRESULT STDMETHODCALLTYPE CManipulationEventSink::ManipulationStarted(
    FLOAT x,
    FLOAT y)
{
    KillTimer(m_hWnd, m_iTimerId);

    return S_OK;
}

HRESULT STDMETHODCALLTYPE CManipulationEventSink::ManipulationDelta(
    FLOAT x,
    FLOAT y,
    FLOAT translationDeltaX,
    FLOAT translationDeltaY,
    FLOAT scaleDelta,
    FLOAT expansionDelta,
    FLOAT rotationDelta,
    FLOAT cumulativeTranslationX,
    FLOAT cumulativeTranslationY,
    FLOAT cumulativeScale,
    FLOAT cumulativeExpansion,
    FLOAT cumulativeRotation)
{
    FLOAT pivot = 0.0f;

    // Apply transformation based on rotationDelta (in radians).
    FLOAT rads = 180.0f / 3.14159f;
    m_dObj->Rotate(rotationDelta*rads, x, y);

    // Apply translation based on scaleDelta.
    m_dObj->Scale(scaleDelta);

    // Apply translation based on translationDelta.
    m_dObj->Translate(translationDeltaX, translationDeltaY);

    if(!m_bInertia)
    {
        // Set values for one-finger rotations.
        FLOAT fPivotRadius = (FLOAT)(sqrt(pow(m_dObj->GetWidth()/2, 2)
                           + pow(m_dObj->GetHeight()/2, 2)))*0.4f;
        FLOAT fPivotPtX    = m_dObj->GetCenterX();
        FLOAT fPivotPtY    = m_dObj->GetCenterY();

        m_manip->put_PivotPointX(fPivotPtX);
        m_manip->put_PivotPointY(fPivotPtY);
        m_manip->put_PivotRadius(fPivotRadius);
    }
    return S_OK;
}

HRESULT STDMETHODCALLTYPE CManipulationEventSink::ManipulationCompleted(
    FLOAT x,
    FLOAT y,
    FLOAT cumulativeTranslationX,
    FLOAT cumulativeTranslationY,
    FLOAT cumulativeScale,
    FLOAT cumulativeExpansion,
    FLOAT cumulativeRotation)
{
    if(!m_bInertia)
    {
        SetupInertia();

        // Kick off timer that handles inertia.
        SetTimer(m_hWnd, m_iTimerId, DESIRED_MILLISECONDS, NULL);
    }
    else
    {
        // Stop timer that handles inertia.
        KillTimer(m_hWnd, m_iTimerId);
    }

    return S_OK;
}

建立 COM 物件並設定 IManipulationProcessor 和 IInertiaProcessor 介面

API 提供 IManipulationProcessor 和 IInertiaProcessor 介面的實作。您應該建立的實例，並從先前實作的 IManipulationEvents 事件接收參考 COM 物件。

處理WM_TOUCH訊息

輸入資料必須從 WM_TOUCH 訊息中擷取，之後必須處理才能饋送正確的操作處理器。

switch (msg)
{
    case WM_TOUCH:

      iNumContacts = LOWORD(wParam);
      hInput       = (HTOUCHINPUT)lParam;
      pInputs      = new TOUCHINPUT[iNumContacts];

      // Get each touch input info and feed each
      // tagTOUCHINPUT into the process input handler.

      if(pInputs != NULL)
      {
          if(GetTouchInputInfo(hInput, iNumContacts,
               pInputs, sizeof(TOUCHINPUT)))
          {
              for(int i = 0; i < iNumContacts; i++)
              {
                  // Bring touch input info into client coordinates.
                  ptInputs.x = pInputs[i].x/100;
                  ptInputs.y = pInputs[i].y/100;
                  ScreenToClient(g_hWnd, &ptInputs);

                  pInputs[i].x = ptInputs.x;
                  pInputs[i].y = ptInputs.y;

                  g_ctDriver->ProcessInputEvent(pInputs[i]);
              }
          }
      }

      delete [] pInputs;
      break;
}

注意

若要使用 ScreenToClient 函式，您必須在應用程式中支援高 DPI。如需支援高 DPI 的詳細資訊，請流覽 MSDN 的高 DPI 區段。

將 TOUCHINPUT 結構傳遞至適當的處理器

使用GetTouchInputInfo函式從WM_TOUCH訊息擷取資料之後，請叫用ProcessUpWithTime、ProcessDownWithTime或ProcessMoveWithTime函數，根據 TOUCHINPUT結構中設定的dwFlag，將資料摘要至操作處理器。

注意

支援多個操作時，如果TOUCHINPUT結構中定義的dwID必須用來將資料傳送至正確的IManipulationProcessor物件，則必須建立新的操作處理器。

CoreObject* coCurrent = m_coHead;

while(coCurrent!=NULL && !bFoundObj)
{
    if(dwEvent & TOUCHEVENTF_DOWN)
    {
        DownEvent(coCurrent, inData, &bFoundObj);
    }
    else if(dwEvent & TOUCHEVENTF_MOVE)
    {
        MoveEvent(coCurrent, inData);
    }
    else if(dwEvent & TOUCHEVENTF_UP)
    {
        UpEvent(coCurrent, inData);
    }
    coCurrent = coCurrent->coNext;
}

VOID CComTouchDriver::DownEvent(CoreObject* coRef, tagTOUCHINPUT inData, BOOL* bFound) {
    DWORD dwPCursor = inData.dwID;
    DWORD dwPTime   = inData.dwTime;
    int x           = inData.x;
    int y           = inData.y;

    // Check that the user has touched within an object's region and fed to the object's manipulation processor.

    if(coRef->doDrawing->InRegion(x, y) &&
        !HasCursor(coRef, dwPCursor))
    {
        ...

        // Feed values to the Manipulation Processor.
        coRef->manipulationProc->ProcessDownWithTime(dwPCursor, (FLOAT)x, (FLOAT)y, dwPTime);

        ...
    }
}

在 ManipulationCompleted 中設定慣性

叫用ManipulationCompleted方法之後，IManipulationProcessor 物件必須設定連結至 IManipulationProcessor之IInertiaProcessor物件的值，才能叫用慣性。下列程式碼範例示範如何從IManipulationProcessor方法ManipulationCompleted設定IInertiaProcessor物件。

    int iVWidth       = GetSystemMetrics(SM_CXVIRTUALSCREEN);
    int iVHeight      = GetSystemMetrics(SM_CYVIRTUALSCREEN);

    RECT rc;
    GetClientRect(m_hWnd, &rc);
    FLOAT lCWidth     = (FLOAT)rc.right;
    FLOAT lCHeight    = (FLOAT)rc.bottom;

    // Set properties for inertia events.

    // Deceleration for tranlations in pixel / msec^2.
    m_inert->put_DesiredDeceleration(0.001f);

    // Deceleration for rotations in radians / msec^2.
    m_inert->put_DesiredAngularDeceleration(0.00001f);

    // Calculate borders and elastic margin to be set.
    // They are relative to the width and height of the object.

    FLOAT fHOffset = m_dObj->GetWidth()  * 0.5f;
    FLOAT fVOffset = m_dObj->GetHeight() * 0.5f;

    // Elastic margin is in pixels - note that it offsets the boundary.

    FLOAT fHElasticMargin = 25.0f;
    FLOAT fVElasticMargin = 25.0f;

    FLOAT fBoundaryLeft   = fHOffset + fHElasticMargin;
    FLOAT fBoundaryTop    = fVOffset + fVElasticMargin;
    FLOAT fBoundaryRight  = lCWidth - fHOffset - fHElasticMargin;
    FLOAT fBoundaryBottom = lCHeight - fVOffset - fVElasticMargin;

    // Set borders and elastic margin.

    m_inert->put_BoundaryLeft(fBoundaryLeft);
    m_inert->put_BoundaryTop(fBoundaryTop);
    m_inert->put_BoundaryRight(fBoundaryRight);
    m_inert->put_BoundaryBottom(fBoundaryBottom);

    m_inert->put_ElasticMarginLeft(fHElasticMargin);
    m_inert->put_ElasticMarginTop(fVElasticMargin);
    m_inert->put_ElasticMarginRight(fHElasticMargin);
    m_inert->put_ElasticMarginBottom(fVElasticMargin);

    // Set initial origins.

    m_inert->put_InitialOriginX(m_dObj->GetCenterX());
    m_inert->put_InitialOriginY(m_dObj->GetCenterY());

    FLOAT fVX;
    FLOAT fVY;
    FLOAT fVR;

    m_manip->GetVelocityX(&fVX);
    m_manip->GetVelocityY(&fVY);
    m_manip->GetAngularVelocity(&fVR);

    // Set initial velocities for inertia processor.

    m_inert->put_InitialVelocityX(fVX);
    m_inert->put_InitialVelocityY(fVY);
    m_inert->put_InitialAngularVelocity(fVR);

清除 COM 物件

當您的應用程式關閉時，您必須清除 COM 物件。下列程式碼示範如何釋放範例中配置的資源。

CComTouchDriver::~CComTouchDriver(VOID) {
    CoreObject* coCurrent = m_coHead;

    // Clean up COM objects.

    while(coCurrent!=NULL)
    {
        coCurrent->inertiaEventSink->Release();
        coCurrent->manipulationEventSink->Release();
        coCurrent->inertiaProc->Release();
        coCurrent->manipulationProc->Release();
        coCurrent = coCurrent->coNext;
    }
}

多點觸控操作應用程式、操作和慣性範例、 Windows Touch 範例

操作和慣性範例

註冊觸控視窗

實作 _IManipulationEventSink 介面

建立 COM 物件並設定 IManipulationProcessor 和 IInertiaProcessor 介面

處理WM_TOUCH訊息

將 TOUCHINPUT 結構傳遞至適當的處理器

在 ManipulationCompleted 中設定慣性

清除 COM 物件

意見反應

意見反應

其他資源

操作和慣性範例

註冊觸控視窗

實作 _IManipulationEventSink 介面

建立 COM 物件並設定 IManipulationProcessor 和 IInertiaProcessor 介面

處理WM_TOUCH訊息

將 TOUCHINPUT 結構傳遞至適當的處理器

在 ManipulationCompleted 中設定慣性

清除 COM 物件

相關主題

意見反應

意見反應

其他資源