Dynamic changing shader at runtime

kokichi8801

Hi guys, I just started using unity and spine about 3 weeks. I got problem when I tried to change shader of spine at runtime.
Here my code :

MeshRenderer meshRen = go.renderer as MeshRenderer;
MyDebug.trace ("before",meshRen.material.shader);
meshRen.material.shader = newSd;
MyDebug.trace ("after",meshRen.material.shader);

Shader was changed after above code but when I checked in

void Update () {
		MyDebug.trace ("update",renderer.material.shader);
	}

This shader still was "Spine/Skeleton", shader was changed back somewhere I didn't find in your source code. I dont have any clue to fix this.

kokichi8801

Pharan

I don't think it has any code that would touch the material shader at all. I wonder why this isn't working.

I've never tried what you did myself though.

kokichi8801

Pharan wrote
I don't think it has any code that would touch the material shader at all. I wonder why this isn't working.

I've never tried what you did myself though.

That's my trouble when I didnt find any line code that change back my shader. You should try sometime 🙂.

Pharan

I seem to recall an old topic here at the forums about material and sharedMaterial. It had something to do with materials being instantiated or something. Something like that might mean changes you make in fields and properties won't reflect on certain objects.

Maybe that's something to look into?

Quick google search returned this: http://answers.unity3d.com/questions/22 ... erial.html

kokichi8801

Thanks pharan for your support. Above solution worked but it leads me to another issue. I only want to change shader at some particular cases ( when something occurs and only for this object ...) while it affect other object even prefab that linked to that object then I have to change it back manually in editor 🙁

Pharan

Sorry, I use Unity but I'm really not familiar with this. Maybe you'll have better luck at the Unity forums.

Just off the top of my head though (assuming material is a settable property as well as a gettable one), it might be that you have to store meshRen's material temporarily in a local variable, then modify it, then set it back.

So something like

MeshRenderer meshRen = renderer as MeshRenderer;
Material mat = meshRen.material;
mat.shader = newShader;
meshRen.material = mat;

That's just my guess. This is totally unfounded other than by that assumption that it is a C# property.
I still recommend you look it up if that doesn't work.

How familiar are you with C# and Unity classes?

kokichi8801

I'm still discovering Unity classes ( C# is not problem to me, I'm programmer btw). Your code only works when I put this in Update(). This may be a solution but I want to find other way to make this situation easier and I'm not sure that it has any performance impact.

Pharan

Being a programmer aside, coming from Java and C++, it took me a while to understand what on earth was going on sometimes, especially when it came to properties vs fields. (and structs, sadly. haha.)

C#, being a younger language than Java, has a few features that make it cleaner and more useful, but also a bit quirky, especially in the way Unity classes have been designed, which doesn't even follow Microsoft's recommended identifier naming conventions so sometimes, you really have to check to see what it's doing.
Unity has a lot of these properties where you think you're getting a reference to the thing but instead, it does some things under the hood and you're not modifying what you think you're modifying. In times like these, I've found it useful consult their forums and documentation often. Sometimes, those don't turn up helpful answers though.

Looks like without using sharedMaterial (which I think gets you access to the material asset), I think you'll be hitting a wall with Spine-Unity's rendering code since I think that keeps pulling info from the atlas data which may be why it only works in Update. Nothing in the code is setting the shaders but I think something in the code is definitely referencing the material asset tied to the AtlasAsset.

Sorry I can't help you with this further. Seems like a bit of a rabbit hole and I'm in the middle of stuff myself.

kokichi8801

Oh, I truly appreciate your help so no need to say sorry. Follow your suggestion, I checked Spine source code again and found that :

// Class SkeletonComponent.cs -> Update():
// Set materials.
		if (submeshMaterials.Count == sharedMaterials.Length)
			submeshMaterials.CopyTo(sharedMaterials);
		else
			sharedMaterials = submeshMaterials.ToArray();
		renderer.sharedMaterials = sharedMaterials;

then only way to achieve my goal is put update material in Update() or LateUpdate() like I said before. Thank you once again 😃

longfei

// Populate submesh when material changes.
Material material = (Material)((AtlasRegion)rendererObject).page.rendererObject;
if(renderer.material.mainTexture != null)
{
         material = renderer.material;
}

I make it by add these lines to solve problem, but I find the lateUpdate function performance is so low.