ImageRenderer.h

// Manages the drawing of image data

#pragma once

#include <d2d1.h>

class ImageRenderer
{
public:
    /// <summary>
    /// Constructor
    /// </summary>
    ImageRenderer();

    /// <summary>
    /// Destructor
    /// </summary>
    virtual ~ImageRenderer();

    /// <summary>
    /// Set the window to draw to as well as the video format
    /// Implied bits per pixel is 32
    /// </summary>
    /// <param name="hWnd">window to draw to</param>
    /// <param name="pD2DFactory">already created D2D factory object</param>
    /// <param name="sourceWidth">width (in pixels) of image data to be drawn</param>
    /// <param name="sourceHeight">height (in pixels) of image data to be drawn</param>
    /// <param name="sourceStride">length (in bytes) of a single scanline</param>
    /// <returns>indicates success or failure</returns>
    HRESULT Initialize(HWND hwnd, ID2D1Factory* pD2DFactory, int sourceWidth, int sourceHeight, int sourceStride);

    /// <summary>
    /// Draws a 32 bit per pixel image of previously specified width, height, and stride to the associated hwnd
    /// </summary>
    /// <param name="pImage">image data in RGBX format</param>
    /// <param name="cbImage">size of image data in bytes</param>
    /// <returns>indicates success or failure</returns>
    HRESULT Draw(BYTE* pImage, unsigned long cbImage);

private:
    HWND                     m_hWnd;

    // Format information
    UINT                     m_sourceHeight;
    UINT                     m_sourceWidth;
    LONG                     m_sourceStride;

     // Direct2D 
    ID2D1Factory*            m_pD2DFactory;
    ID2D1HwndRenderTarget*   m_pRenderTarget;
    ID2D1Bitmap*             m_pBitmap;

    /// <summary>
    /// Ensure necessary Direct2d resources are created
    /// </summary>
    /// <returns>indicates success or failure</returns>
    HRESULT EnsureResources();

    /// <summary>
    /// Dispose of Direct2d resources 
    /// </summary>
    void DiscardResources();
};