Converter generates invalid texture coordinates

[pjcozzi]

Using collada.zip from https://groups.google.com/forum/#!topic/cesium-dev/WKndeTmqEW8

This model loads OK in Mac preview:

But once converted to glTF, it is a solid color:

A quick tweak to the shader:

gl_FragColor = vec4(v_texcoord0, 0.0, 1.0);

shows that the texture coordinates are black.

This is because the generated semantics between the attributes and parameters are mismatched.

                "texcoord0": {
                    "semantic": "TEXCOORD_2",
                    "type": 35664
                }

TEXCOORD_2 should be TEXCOORD_0.

[fabrobinet]

@pjcozzi There are at least 2 issues with the DAE:

• <effect id="Effect"> contains in the diffuse slot 2 texture slot, I am not sure what it is supposed to mean, I don't think that is valid.
• multiple UV sets are referenced as here:

<bind_vertex_input semantic="cityengine_colormap" input_semantic="TEXCOORD" input_set="0"/>
 <bind_vertex_input semantic="cityengine_colormap" input_semantic="TEXCOORD" input_set="1"/>
<bind_vertex_input semantic="cityengine_colormap" input_semantic="TEXCOORD" input_set="2"/>
<bind_vertex_input semantic="cityengine_colormap" input_semantic="TEXCOORD" input_set="3"/>
<bind_vertex_input semantic="cityengine_colormap" input_semantic="TEXCOORD" input_set="4"/>
<bind_vertex_input semantic="cityengine_colormap" input_semantic="TEXCOORD" input_set="5"/>

but only one UV set is defined in the mesh.

[fabrobinet]

I'll dig a bit more and see how to handle this situation in a better way...

[fabrobinet]

Implemented a work-around in dev-6. Model displays correctly now in my viewer.
@pjcozzi just to close the loop, you probably want to the originator of this DAE the issues reported in the comment just above.

[pjcozzi]

OK, thanks @fabrobinet