Hello. I’m following Writing Custom Materials tutorials. This is code fragment:

This works fine. Now I change code a little:

And my screen is empty. Why?

P.S.: This construction works

Maybe because you should activate vertex buffer sequentially

What does it mean - sequentially? I have one buffer and just interesting - why I can’t assign it to 2nd register (va1)?

i think it’s like an array, why you should use array[1] instead of array[0] ?
What you should do is activate VertexBuffers sequentially.
If you need only one VertexBuffer use the 0.

I’m not sure i’ve been clear.

Yeah, I understand you, thank you. I’m just curious - in activateVertexBuffer I need to specify register index. In AGAL I need to specify register too. In raw application (without any 3D engines) it’s absolutely legal to assign stream to, say 5th index and all works fine. In away3D it doesn’t work. So why do it needed to specify these index in activateVertexBuffer then?

Oh i’m not sure of what i said, i’m just following a logical reasoning.
I’ll check.

Ok i’ve searched a little bit and that’s what i’ve found:
I followed the activateVertexBuffer method and i’ve found that multiple classes implements it (IRenderable), i choose SubGeometry for example and that’s what i’ve found:

It seems that it doesn’t take in account the index passed but asks directly to stage3dProxy what’s the next free index.
That’s why if you use index 1 you don’t see anything, because it’s activating the first buffer free ( in this case the 0)

Yeah, I saw this code. Actually, it takes passed index into account (index:int field). All things happens in MaterialPassBase.updateProgram method. I don’t know why, but away3D adds some shader code. My vertex string was

m44 op, va1, vc0

and after some inside magic it becomes

mov vt0, va0
m44 op, va1, vc0

As you can see - now shader contains va0. But since it’s empty, geometry not drawn.

P.S.: actually I forgot to enable context.enableErrorChecking. That’s why It was difficult to realize real propblem.

ehm yes the method receive the index but never use it….if you look carefully you’ll see that index it’s not used

No no. It used in

context.setVertexBufferAt(index, _vertexBuffer[contextIndex], 0, Context3DVertexBufferFormat.FLOAT_3);

My problem is solved (actually, not solved, but now it’s clear there’s it from) - it’s all about autogenerated shader in MaterialPassBase.updateProgram()

oh sh*t i’ve missed it!!!

Ok i’m looking at updateprogram, yes it adds code for animation and UVanimation:

vertexCode it’s your original code.

found!!!!!
if you don’t have animationsets assigned it uses the default vector that’s animatableattributes, it’s initialized like this:

this is at the top of MaterialPassBase