Texture simply duplicates the first pixel

Texture simply duplicates the first pixel

• Tom Rahav

  Maybe this is a result of different FSAA settings in the control panel for the hardware. That was the reason why I am notice the half pixel offset. Without AA and points sampling you don’t need it but as soon as you use AA bad things can happen if you don’t care about the pixel center.

  
  
  

• francois974

  Managed DirectX is only a small layer over the C++ version. Because of this everything that is defined for C++ is still in place if you use C#. The texture coordinates don’t get this offset. You have to apply it to the position.

  
  
  

• ActiveBrian

  I copied your code with very minimal changes into the EmptyProject sample from the SDK and it worked perfectly. So that leads me to think there is something up elsewhere in your code.

  1st obvious thing to check is that your are loading the bitmap you think you are. A bitmap file called 'red' makes me think it might all be red :-) Since you have no paths it will be loading the file from the start directory which will default to bin/debug

  Are there any texture states or render states set anywhere in the code

  
  
  

• Jude A

  Sorry to say the texture appears perfectly on my PC.

  So what is left to try

  1. Try creating the device using the reference rasterizer and see if your texture appears

  2. Try running some other texture code and see if that works http://www.c-unit.com/tutorials/mdirectx/ t=37 would be a good one.

  3. Upgrade/downgrade your video card driver to a WHQL certified one and see if that makes a difference.

  As for the half pixel offset, that may be a problem you have to deal with later. Its normal effect is to make your texture appear blurry - I've never seen it turn a whole texture one color before but Ralf thinks it may be an interaction with FSAA - so try looking at your graphics card settings in control panel to see if you have any odd settings turn on, or high performance etc.

  
  
  

• dglane

  Well I added those renderstates to my code, still works. Maybe put the zip the whole project and the bitmap and put it on a site somewhere (or email it to me). I don't see anything obviously wrong.

  
  
  

• Tiago Nobrega

  Interesting - that looks fine to me. Or, more importantly, it doesn't look like it'd have any obvious visual artifacts...

  The only other thing that I've had cause these sorts of problems is a mismatched vertex declaration (or FVF). If you get those wrong then the GPU will read the incorrect bit of raw-binary as a texture coordinate and you'll get all sorts of funky results.

  I think this might be your problem - you're using TransformedTextured, which at a guess is (D3DFVF_XYZRHW|D3DFVF_TEX1) to people like me (). That would mean you'd have to have a 'w' component in your vertex. Without that you'll get the situation I just described - it might be reading 'tu' as the 'w' coordinate and 'tv' as the 'u' coordinate and then the 'x' of the next vertex as 'tv' - or something suitably broken.

  hth
  Jack

  
  
  

• Cognitronic

  I have render states for alpha blending (from a previous part of the tutorial). The texture I'm trying to load is a big block of red with black scribbles and a single green pixel in the upper left, and naturally, the entire thing is green.

  I'll add the other two methods that deal with graphics. Thanks in advance.

  public bool InitializeGraphics()

  {

  try {

  // Now let's setup the Direct3D stuff

  Direct3D.PresentParameters presentParams = new Direct3D.PresentParameters();

  if (windowed == true)

  {

  presentParams.Windowed = true;

  }

  else

  {

  presentParams.Windowed = false;

  Direct3D.Format current = Direct3D.Manager.Adapters[0].CurrentDisplayMode.Format;

  presentParams.BackBufferCount = 1;

  presentParams.BackBufferFormat = current;

  presentParams.BackBufferWidth = screenWidth;

  presentParams.BackBufferHeight = screenHeight;

  }

  presentParams.SwapEffect = Direct3D.SwapEffect.Discard;

  // Create the graphics

  graphics = new Direct3D.Device(0, Direct3D.DeviceType.Hardware, this, Direct3D.CreateFlags.SoftwareVertexProcessing, presentParams);

  graphics.RenderState.CullMode = Direct3D.Cull.None;

  graphics.RenderState.AlphaBlendEnable = true;

  graphics.RenderState.AlphaBlendOperation = Direct3D.BlendOperation.Add;

  graphics.RenderState.DestinationBlend = Microsoft.DirectX.Direct3D.Blend.InvSourceAlpha;

  graphics.RenderState.SourceBlend = Microsoft.DirectX.Direct3D.Blend.SourceAlpha;

  // Setup the event handlers for the graphics

  graphics.DeviceLost += new EventHandler(this.InvalidateDeviceObjects);

  graphics.DeviceReset += new EventHandler(this.RestoreDeviceObjects);

  graphics.Disposing += new EventHandler(this.DeleteDeviceObjects);

  graphics.DeviceResizing += new CancelEventHandler(this.EnvironmentResizing);

  return true;

  } catch (DirectXException) {

  return false;

  }

  }

  protected virtual void Render()

  {

  if (graphics != null)

  {

  if (graphicsLost)

  {

  try

  {

  graphics.TestCooperativeLevel();

  }

  catch (Direct3D.DeviceLostException)

  {

  // device cannot be reaquired yet, just return

  return;

  }

  catch (Direct3D.DeviceNotResetException)

  {

  // device has not been reset, but it can be reaquired now

  graphics.Reset(graphics.PresentationParameters);

  }

  graphicsLost = false;

  }

  try

  {

  graphics.Clear(Direct3D.ClearFlags.Target, Color.Black, 1.0f, 0);

  graphics.BeginScene();

  graphics.SetTexture(0, texture);

  graphics.VertexFormat = Direct3D.CustomVertex.TransformedTextured.Format;

  graphics.DrawUserPrimitives(Direct3D.PrimitiveType.TriangleStrip, 2, vertexes);

  // TODO : Scene rendering

  graphics.EndScene();

  graphics.Present();

  }

  catch (Direct3D.DeviceLostException)

  {

  graphicsLost = true;

  }

  }

  
  

• David Johnson MCSD

  Sent it. Thanks for the help.

  BTW, Ralf, are you certain that C# uses the half-pixel offset. All of the documentation I've found indicates that texture coordinates are a scalar between 0 and 1. I know C++ uses it (via the link you gave me), but I don't think c# does.

  
  

• jaedge

  Looks like you are missing to subtract the half pixel offset to compensate the different pixel center that Direct3D use:

  Http://msdn.microsoft.com/library/en-us/directx9_c/Directly_Mapping_Texels_to_Pixels.asp frame=true

  
  
  

• rockybooth

  All right, I think I left out a vital piece of information. (and I don't know why, as it should have been obvious). I'm programming in C#, and am new to DirectX. I'm using a tutorial written for 9.0b and adjusting my code as necessary. This is the first time where I haven't been able to figure out code to accomplish the same task as the tutorial suggested.
  

• Smurble

  Well, that makes things more difficult.

  Lots of that post is over my head, even after a bit of googling, but responding to what I do understand:

  Other texture's work (including the specific tutorial you gave me).

  Regarding high performance mode, if I look at my adapter settings (display properties, settings, advanced) The troubleshoot tab has the hardware acceleration that can be set between none and full (I incrementally lowered this until my program crashed). I don't know if this is what you mean.

  The only other possibly enlightening thing I saw was under a tab called "PowerPlay" (which I think is an ATI-specific tab), it says that the graphics adapter is running in high performance mode, but I couldn't find anything to change that. If I lowered the Hardware acceleration bar too far, the tab would vanish, but until then, it said the same thing.

  If you know a way to change it from high performance mode, I can try that, otherwise, I think I'm at the end of the line.

  
  

• KarlH

  Hello everyone, i have exactly the same problem here. In fact it's the same code.

  The code is from the book "Beginning C# Game Programming" and i get only the first pixel drawn. This book was written when DirectX 9.b was in use. Even the author said that there were some differences to consider between his code and the new version (at that time) DirectX 9.c.

  Just like Takalth, i'm using an ATI video card (mine is a Mobility card). May the default configuration from ATI cards be the problem I have seen a lot of projects on the web that run wonderfully on my machine, using textures (really complex code compared to the code from the book), but my code doesn't work.

  I almost forget. I'm using DirectX 9.c to build my code. What version did everyone who succeed use

  Greetings

  
  

• ihsansolak

  I would be surprised if it's incorrectly loading the texture data, so I think you need to post your texture coordinate generation code.
  
  If you want the whole texture to be displayed, you need to be specifying values from 0.0 to 1.0 depending on the shape of your vertices/triangles.
  
  Incorrect texture coordinates can cause all sorts of unexpected texturing results
  
  hth
  Jack
  
  
  

• AnaXyd

  Here is the code. I'm rendering onto a large square. The square renders as all one color, and it's always the first pixel in my bitmap. Thanks

  vertexes = new Direct3D.CustomVertex.TransformedTextured[4];

  // top-left vertex:

  vertexes[0].X = screenWidth / 4.0f;

  vertexes[0].Y = screenHeight / 4.0f;

  vertexes[0].Z = 0.0f;

  vertexes[0].Tu = 0.0f;

  vertexes[0].Tv = 0.0f;

  // top-right vertex:

  vertexes[1].X = (screenWidth / 4.0f) * 3.0f;

  vertexes[1].Y = screenHeight / 4.0f;

  vertexes[1].Z = 0.0f;

  vertexes[1].Tu = 1.0f;

  vertexes[1].Tv = 0.0f;

  // bottom-left vertex:

  vertexes[2].X = screenWidth / 4.0f;

  vertexes[2].Y = (screenHeight / 4.0f) * 3.0f;

  vertexes[2].Z = 0.0f;

  vertexes[2].Tu = 0.0f;

  vertexes[2].Tv = 1.0f;

  // bottom-right vertex:

  vertexes[3].X = (screenWidth / 4.0f) * 3.0f;

  vertexes[3].Y = (screenHeight / 4.0f) * 3.0f;

  vertexes[3].Z = 0.0f;

  vertexes[3].Tu = 1.0f;

  vertexes[3].Tv = 1.0f;

  
  
• Texture simply duplicates the first pixel