Translucency issue using SharpDX on WinRT

Question

I'm having a translucency issue using sharpdx for winrt. First of all, my code:

On the Mainpage.xaml, I've add a swapchainPanel like this:

<Grid>
  <SwapChainPanel  x:Name="Panel" />
</Grid>  
// There is nothing else...

I've used the same class as the sample from github, for the 3D models rendering:

// Initialisation part
graphicsDeviceManager = new GraphicsDeviceManager(this);
graphicsDeviceManager.PreferredGraphicsProfile = new FeatureLevel[] { FeatureLevel.Level_11_0, };
graphicsDeviceManager.DepthBufferShaderResource = true;

Still in the same class, when loading contents:

models = new List<Model>();
foreach (var modelName in new[] {"dude"}) 
{
   model = Content.Load<Model>(modelName); 
   BasicEffect.EnableDefaultLighting(model, true); 
   models.Add(model);
}
model = models[0]; 
// Instantiate a SpriteBatch
spriteBatch = ToDisposeContent(new SpriteBatch(GraphicsDevice)); 
base.LoadContent();

And finally, the draw part:

// Clears the screen with the Color.CornflowerBlue
   GraphicsDevice.Clear(Color.CornflowerBlue);
   model.Draw(GraphicsDevice, world, view, projection);
   base.Draw(gameTime);

Everything render fine, but this is what I got for a textured model (It's a bit tricky to notice the translucency on a screenshot...)

Here is what I have with a non-textured model...

I think it comes from rendering in Alpha mode. I've tried to set the BlendState but I get some Exceptions since I'm not using the right parameters.

Answer 1

Ok after some several gradual checks as suggested by @xoofx (thanks :) )

I found that there are some issues using SharpDx.

• The ModelRendering sample come with .dae models. When I launch this sample, Everything workes fine and there is no issue.

• When I load my model, exported on .dae, .fbx and .obj, transluncency appears with .dae, .fbx, but the toolkit compiler can't compile .obj files that have .mtl associated since some primitives and files tag aren't in the correct format. (even if I check the XNA compatibility in Blender when Exporting)

So what have I done to solve my problem ?

1 - Decrease or make sure my graphic profil is the right profil since I'm on a Intel graphic 4000 that doesn't support directX 11.1 yet...

 graphicsDeviceManager.PreferredGraphicsProfile = new FeatureLevel[] { FeatureLevel.Level_11_0, };

2 - Delete everything that the toolkit compiler generated in the Debug directory. I think the compiler doesn't generate twice a file when it already exists/compiled.

3 - Finally, I've noticed that all the part in white/transparent on the pictures in my question are all textured. That kind of color comes from this combination:

• I've apply a texture on a model or model part.
• Unfortunatly, the Toolkit compiler can't find the texture or the texture value is void.
• But when you apply a Texture on a model, surface Specular highlight will be activated, especially the MaterialSpecular (that you can see on a model's part property in VisualStudio. MaterialSpecular takes 4 values : R, G, B and A for Alpha always set the Alpha to 1. My aplha was 0 sometimes :( ).

So the light is freakily reflected and tadaaa we got a beautiful translucent model :)

Also, I Export my model into .fbx and make sure to display the default gray plain color on part that are not textured.

4 - Last but not least, Enable default lightning on the Model.

 BasicEffect.EnableDefaultLighting(model, true);