Question

I’m having trouble loading a textured model with alpha blending from blender to xna.

On blender I know that the texture has the correct alpha values, but whenever I draw the model into my game the extra space that was supposed to be transparent is instead filled black

This is what my draw method looks like.

public void draw()
    {

        Matrix posTranslated = Matrix.CreateTranslation(position); 
        foreach (ModelMesh mesh in model.Meshes)
        {
            foreach (BasicEffect effect in mesh.Effects)
            {
                effect.EnableDefaultLighting();


                effect.View = view;
                effect.Projection = proj;
                effect.World = modelTransforms[mesh.ParentBone.Index] * posTranslated;
            }

            mesh.Draw();

        }
    }

am I missing any effects or changes to the graphics device? I’ve been searching for days and have still had little luck with this issue. Please help T.T

Answer 1

Have you set these properties?

graphicsDevice.RenderState.AlphaBlendEnable = true;
graphicsDevice.RenderState.SourceBlend = Blend.SourceAlpha;
graphicsDevice.RenderState.DestinationBlend = Blend.InverseSourceAlpha;

If you’re using XNA 4.0 you need to set the blend state instead of the old RenderState.

BlendState blendState = new BlendState()
{
    AlphaSourceBlend = Blend.SourceAlpha,
    AlphaDestinationBlend = Blend.InverseSourceAlpha, 
    ColorDestinationBlend = Blend.InverseSourceAlpha, // Required for Reach profile
};
GraphicsDevice.BlendState = blendState;