| Microsoft DirectX 8.1 (C++) |
The CDrawImage class is a worker class for the owning CBaseWindow object. It handles the actual drawing operation from that class. To use this class, be sure to call CDrawImage::NotifyAllocator when the allocator has been agreed upon, and call CDrawImage::NotifyMediaType with a pointer to a CMediaType object (which must not be stack-based, because a pointer is maintained by this class rather than making a copy) when that is agreed.
When the palette changes, call CDrawImage::IncrementPaletteVersion, and before rendering call CDrawImage::SetDrawContext so that the class can obtain the handle to a device context (HDC) handles from the owning CBaseWindow object.
Protected Data Members
| m_bStretch | Flag to stretch the images. |
| m_bUsingImageAllocator | Flag to determine if samples share DIBSECTION structures. |
| m_EndSample | End time for the current sample. |
| m_hdc | Main window device context (DC). |
| m_MemoryDC | Off-screen draw DC. |
| m_pBaseWindow | Owning video window object. |
| m_PaletteVersion | Current palette version token. |
| m_perfidRenderNow | Moment when returned from draw (for performance logging). |
| m_perfidRenderTime | Time taken to render an image (for performance logging). |
| m_pMediaType | Pointer to the current media type format. |
| m_SourceRect | Source image rectangle. |
| m_StartSample | Start time for the current sample. |
| m_TargetRect | Destination rectangle. |
Member Functions
| CDrawImage | Constructs a CDrawImage object. |
| DisplaySampleTimes | Displays a |
| DrawImage | Looks after drawing an image to a window. |
| FastRender | Draws an image using BitBlt and StretchBlt. |
| GetPaletteVersion | Retrieves the currently installed palette version. |
| GetSourceRect | Retrieves the current source rectangle. |
| GetTargetRect | Retrieves the current target rectangle. |
| IncrementPaletteVersion | Increments the current palette version. |
| NotifyAllocator | Notifies the draw object which allocator is being used. |
| NotifyEndDraw | Indicates the conclusion of image rendering. |
| NotifyMediaType | Passes the media type established during connection. |
| NotifyStartDraw | Indicates the beginning of image rendering. |
| ResetPaletteVersion | Resets the current palette version. |
| ScaleSourceRect | Retrieves a scaled version of a provided source rectangle. |
| SetDrawContext | Sets the window and off-screen device contexts to draw with. |
| SetSourceRect | Sets the source rectangle for the video. |
| SetStretchMode | Determines whether it is necessary to stretch. |
| SetTargetRect | Sets the target rectangle for the window. |
| SlowRender | Uses the Microsoft® Win32® SetDIBitsToDevice and StretchDIBits functions to draw an image. |
| UpdateColourTable | Updates the palette held in a DIBSECTION structure. |
| UsingImageAllocator | Retrieves the type of samples to be drawn. |