I created a model (representing a laser beam) in the XSI mod tool an exported it as an .fbx model for use in an XNA arcade game I am playing with.  The model rendered fine (although it was initially too small, because I am using the Space War starter kit models as well).  My initial starting point for the program was the Tutorial 4: Make a Game in 60 Minutes package, in it's freshly downloaded state.

I switched to using the Game State Management Sample as a framework, bringing my code in to the GamePlayScreen class.  After a little bit of debugging, I had the game working again, except the laser model was not being rendered.  It was there as far as collisions are concerned, but it is invisible in game.  I can switch the model to another, say one of the Space War ships, and it will render fine.  I have found that the red projectile looking blob from the Space War kit, does not render either.

Btw, I went back to the Tutorial 4 starting code and replaced the ship model with the laser model and it does still render.

Does anyone have any suggestions?

Thank you in advance,

Dave

Are you using SpriteBatch anywhere? If so you'll want to read this: http://blogs.msdn.com/shawnhar/archive/2006/11/13/spritebatch-and-renderstates.aspx.

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Nick Gravelyn -- Microsoft XNA MVP
XNA Wiki | Zune Games

I most definitely am using SpriteBatch.  I will look in to this, and update this thread.

Thanks,

Dave

Unfortunately that was not the answer.  I even tried removing the SpriteBatch entirely with no change.

The model from the Space War pack that also does not render is mgun_proj.x

Any other suggestions would be greatly appreciated!

Thanks,

Dave

Without seeing your render code, there's not much chance of us helping you at this point.

 

This is almost certainly a renderstate issue, but it's impossible to say what without a full copy of your code to experiment with.

Perhaps your model or textures contain zero alpha values, and you have alpha testing renderstates turned on?

Maybe the model has a wrong winding order, and you have the cullmode renderstate set?

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XNA Framework Developer
blog - homepage

I finally figured it out. 

It was due to the order in which I loaded the model and SetupEffectDefaults.

If I did those two before setting projectionMatrix and viewMatrix the model would not be rendered.  By moving the content.Load<Model>("Models/Laser") and SetupEffectDefaults to after those, it renders fine.

Thanks,

Dave