Generating Debug Bitmaps for DirectX

WEBINAR: On-demand webcast

How to Boost Database Development Productivity on Linux, Docker, and Kubernetes with Microsoft SQL Server 2017 REGISTER >

Introduction

Debugging a DirectX application is not the easiest thing to do. Most times, you're looking for reasons why your image did not display on the screen or why it displayed incorrectly. The following snippet of code should help in your debugging efforts. Cut and paste it to your DirectX program and call it before calling the DirectX Present() method. It will allow you to capture an image of a screen buffer into a bitmap file. Each image is named in a sequential fashion. This will provide a snapshot of exactly what is being presented to the screen.

Notes:
  1. This code assumes you have one back buffer defined.
  2. This code assumes your DirectX device is defined as 'windowed'.
  3. m_rect is the CRect for the associated device window.
//
// This method is used for debugging. It will dump the current
// back buffer surface to a bitmap. This provides a snapshot of
// what is currently ready for presentation.
//
void debug_dump_buffer()
{
   IDirect3DSurface9* pRenderTarget=NULL;
   IDirect3DSurface9* pDestTarget=NULL;
   D3DDISPLAYMODE d3ddisplaymode;

   // sanity checks.
   if (pDirect3DDevice == NULL)
      return;

   // get the render target surface.
   HRESULT hr = pDirect3DDevice->GetRenderTarget(0, &pRenderTarget);
   // get the current adapter display mode.
   hr = pDirect3D->GetAdapterDisplayMode(D3DADAPTER_DEFAULT,
                                         &d3ddisplaymode);
   // create a destination surface.
   hr = pDirect3DDevice->CreateOffscreenPlainSurface(m_rect.Width(),
                         m_rect.Height(),
                         d3ddisplaymode.Format,
                         D3DPOOL_SYSTEMMEM,
                         &pDestTarget,
                         NULL);
   //copy the render target to the destination surface.
   hr = pDirect3DDevice->GetRenderTargetData(pRenderTarget,
                                             pDestTarget);
   //save its contents to a bitmap file.
   file.Format("DX Buffer %d.bmp", ndebug++);
   hr = D3DXSaveSurfaceToFile(file,
                              D3DXIFF_BMP,
                              pDestTarget,
                              NULL,
                              NULL);

   // clean up.
   pRenderTarget->Release();
   pDestTarget->Release();
}


Comments

  • There are no comments yet. Be the first to comment!

Leave a Comment
  • Your email address will not be published. All fields are required.

Top White Papers and Webcasts

  • As all sorts of data becomes available for storage, analysis and retrieval - so called 'Big Data' - there are potentially huge benefits, but equally huge challenges...
  • The agile organization needs knowledge to act on, quickly and effectively. Though many organizations are clamouring for "Big Data", not nearly as many know what to do with it...
  • Cloud-based integration solutions can be confusing. Adding to the confusion are the multiple ways IT departments can deliver such integration...

Most Popular Programming Stories

More for Developers

RSS Feeds

Thanks for your registration, follow us on our social networks to keep up-to-date