Generating Debug Bitmaps for DirectX

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  • Your email address will not be published.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

  • Live Event Date: October 29, 2014 @ 11:00 a.m. ET / 8:00 a.m. PT Are you interested in building a cognitive application using the power of IBM Watson? Need a platform that provides speed and ease for rapidly deploying this application? Join Chris Madison, Watson Solution Architect, as he walks through the process of building a Watson powered application on IBM Bluemix. Chris will talk about the new Watson Services just released on IBM bluemix, but more importantly he will do a step by step cognitive …

  • It's no secret what keeps CIOs up at night. Mobile, cloud, data, security, and social have become the "five imperatives," the drivers of business progress, innovation, and competitive differentiation. Business leaders around the world want to hear how other companies are succeeding. How are they applying the latest technologies? How did they get started? What outcomes are they achieving? Read this online magazine for success stories from organizations like the NBA, Pfizer, and San Jose State University as they …

Most Popular Programming Stories

More for Developers

Latest Developer Headlines

RSS Feeds