TypeError: Object doesn't support property or method 'bufferSubData'.

[Rashed Sourov]

I have a vertex attribute which is dynamic. In need to update parts of the data of that vertex attribute. gl.bufferSubData is needed for me.

In Threejs, we can make a BufferAttribute dynamic and update parts of the buffer using update range and offset.

While doing this i am getting this error message -

TypeError: Object doesn't support property or method 'bufferSubData'.

Here is the log -

TypeError: Object doesn't support property or method 'bufferSubData'
   at updateBuffer (three.js:9720:5)
   at update (three.js:9767:5)
   at update (three.js:16955:5)
   at update (three.js:17391:5)
   at projectObject (three.js:22160:7)
   at projectObject (three.js:22196:5)
   at projectObject (three.js:22196:5)
   at projectObject (three.js:22196:5)
   at projectObject (three.js:22196:5)
   at projectObject (three.js:22196:5)

Could this be related to the version of the ANGLE?

[Cristi Petruta]

Fixed in develop/buffer-subdata

[Rashed Sourov]

Hello Cristi,

I am getting error while using buffersubdata in this line -

RETURN_INVALID_REF_IF_JS_ERROR(JsGetArrayBufferStorage(arguments[4], &data, &dataLength));

Here is the log -

Failure in file d:\works\holojs\holojs\holojshost\webglprojections.cpp, line 817

Please let me know if you need any information from me.

[Cristi Petruta]

Can you provide a minimum script repro? I'm not getting this error.

[Rashed Sourov]

Hello Cristi

Sorry for the late. let me describe what i am doing -

First, i create a custom vertex attribute alphaValue like this -

        let alpha_array_length = volumeFaceGeometry.attributes.position.array.length / 3;
        let __alpha_values = new Float32Array(alpha_array_length);
        for (let i = 0; i < alpha_array_length; i++) {
            __alpha_values[i] = 1.0;
        }

        volumeFaceGeometry.addAttribute('alphaValue', new THREE.BufferAttribute(__alpha_values, 1));
        volumeFaceGeometry.attributes.alphaValue.dynamic = true;

        console.log("Position attribute length: " + volumeFaceGeometry.attributes.position.array.length);
        console.log("Alpha attribute length: " + volumeFaceGeometry.attributes.alphaValue.array.length);

For a test .step model, i get the following output from the two console logs (which is correct output) -

log: Position attribute length: 2814
log: Alpha attribute length: 938

This is how i update my custom vertex attribute alphaValue -

// This is for testing, this range is valid for my test model
  let startVertex = 0;
  let endVertex = 500;

  let alphaArray = volumeFaceGeometry.attributes.alphaValue.array;
 
  // update the value in the array
  for (let i = startVertex; i < endVertex; i++) {
          alphaArray[i] = 0.5;
  }
  volumeFaceGeometry.attributes.alphaValue.needsUpdate = true;
  volumeFaceGeometry.attributes.alphaValue.updateRange.offset = startVertex;
  volumeFaceGeometry.attributes.alphaValue.updateRange.count = endVertex - startVertex;

  // This we have to do because of a threejs bug
  // At this point, the glBufferSubdata is called and the error is shown
  renderer.render(scene, camera, dummyRenderTexture);

Please let me know if you need more info.

[Cristi Petruta]

I merged in a fix for this.

[Rashed Sourov]

@Almost-Done

Thank you! I am unable to test it right now. Previously i was loading a step model in my app. But now i cant see the model (its the same solution without any modification)! I only updated my Visual Studio 17 to a new update.

I will check more on this and get back to you shortly.

[Rashed Sourov]

@Almost-Done

The bug is fixed. Now the buffersubdata is working properly.

I will create a separate bug for "mesh is not rendering if i build with Visual Studio Community 2017 version 15.5.6".