Creating Materials/Textures through script

Help & Support
1

Hi. I am running a local copy of playcanvas, ie, not using the online editor.
I have a basic model and a texture.
I have uploaded both to the playcanvas online editor and produced JSON files.
I am left with

  • model.json
  • material.json
  • texture.png

I went in to material.json to fix the path to texture.png

So far I can successfully add a model to the game, but am stuck on the process for materials/textures.

// Model
let file = {
   filename: "model.json",
   url: "/model.json"
};
let model = new pc.Asset("test_model", "model", file);
model.id = 123;
model.preload = true;
app.assets.add(model);

// This works
let test = new pc.Entity();
test.addComponent('model');
test.model.asset = app.assets.find("test_model");
app.root.addChild(test);

But I am not sure how to add a material.
I have tried this with no luck. I get “Error: Can’t set id and url”

// Material
let file = {
   filename: "material.json",
   url: "/material.json"
};
let material= new pc.Asset("test_material", "material", file);
material.id = 333;
material.preload = true;
app.assets.add(material);

// This also fails, but, probably for other reasons
test.model.asset = this.engine.assets.find("test_model"); 
test.model.meshInstances[0].material = material.resource;

So how do I use code to create a material from a downloaded material.json and also apply it to a model or entity?

2

Hi @tones31,

Can you try loading the asset after adding it to the assets registry?

app.assets.add(material);
app.assets.load(material);

Your code seems correct, this line should apply the material to the model, if it was correctly loaded:

test.model.meshInstances[0].material = material.resource;
3

Hm… I’ve tried that, among a few other things. Now I am also noticing that

test.model.meshInstances

is null even after setting test.model.asset. Does this indicate something wrong with the entity or with the model asset?

4

Most likely the model hasn’t been loaded correctly. Can you check in addition the following for being null?

test.model.model.meshInstances
5

Actually, test.model.model is null! And yet I see the models rendered on the canvas! Just no texture of course.

6

It looks like assets are not loaded yet…
When I create them, there’s a network request for each .json asset.
But the are still pending while I am then trying to assign them to an entity.
I have preload set to true, and I call load as you suggest for mat/model, but they are not loaded fast enough. Is there a blocking way to preload?

7

Not sure what’s going on here, maybe try uploading your project to a GitHub repo so we can take a look.

The Playcanvas engine examples are a good place to see how engine only asset loading should work:

8

Hm, do I need to be using app.assets.loadFromUrl ?

9

You can use that as well, it takes care of creating the and returning the a new pc.Asset instance. So there is no need creating it manually and adding it to the assets registry.

11

I went with loadFromUrl and it really solved all of my problems.

1 Like