FBALL.H

//==========================================================================; 
// 
//  THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY 
//  KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE 
//  IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR 
//  PURPOSE. 
// 
//  Copyright (c) 1992 - 1997  Microsoft Corporation.  All Rights Reserved. 
// 
//--------------------------------------------------------------------------; 
 
// Generates a movie on the fly of a bouncing ball... 
 
// The class managing the output pin 
class CBallStream; 
 
// Main object for a bouncing ball filter 
class CBouncingBall : public CSource 
{ 
 
public: 
 
    // The only allowed way to create Bouncing balls! 
    static CUnknown * WINAPI CreateInstance(LPUNKNOWN lpunk, HRESULT *phr); 
 
private: 
 
    // It is only allowed to to create these objects with CreateInstance 
    CBouncingBall(LPUNKNOWN lpunk, HRESULT *phr); 
 
}; // CBouncingBall 
 
 
// CBallStream manages the data flow from the output pin. 
class CBallStream : public CSourceStream 
{ 
 
public: 
 
    CBallStream(HRESULT *phr, CBouncingBall *pParent, LPCWSTR pPinName); 
    ~CBallStream(); 
 
    // plots a ball into the supplied video frame 
    HRESULT FillBuffer(IMediaSample *pms); 
 
    // Ask for buffers of the size appropriate to the agreed media type 
    HRESULT DecideBufferSize(IMemAllocator *pIMemAlloc, 
                             ALLOCATOR_PROPERTIES *pProperties); 
 
    // Set the agreed media type, and set up the necessary ball parameters 
    HRESULT SetMediaType(const CMediaType *pMediaType); 
 
    // Because we calculate the ball there is no reason why we 
    // can't calculate it in any one of a set of formats... 
    HRESULT CheckMediaType(const CMediaType *pMediaType); 
    HRESULT GetMediaType(int iPosition, CMediaType *pmt); 
 
    // Resets the stream time to zero 
    HRESULT OnThreadCreate(void); 
 
    // Quality control notifications sent to us 
    STDMETHODIMP Notify(IBaseFilter * pSender, Quality q); 
 
private: 
 
    int m_iImageHeight;                // The current image height 
    int m_iImageWidth;                // And current image width 
    int m_iRepeatTime;                  // Time in msec between frames 
    const int m_iDefaultRepeatTime;     // Initial m_iRepeatTime 
    BYTE m_BallPixel[4];        // Represents one coloured ball 
    intm_iPixelSize;                // The pixel size in bytes 
    PALETTEENTRY m_Palette[256];// The optimal palette for the image 
    CCritSec m_cSharedState;        // Lock on m_rtSampleTime and m_Ball 
    BOOL m_bZeroMemory;                 // Do we need to clear the buffer 
    CRefTime m_rtSampleTime;        // The time stamp for each sample 
    CBall *m_Ball;                // The current ball object 
 
    // set up the palette appropriately 
    enum Colour {Red, Blue, Green, Yellow}; 
    HRESULT SetPaletteEntries(Colour colour); 
 
}; // CBallStream