Hard Normals about daeblend HOT 7 CLOSED

I've implemented a workaround in my fork, which is ok for me but totally overkill in objective terms.
Basically, I first export to DAE using the built-in bpy DAE exporter, then using your exporter and then splice both xml together... I won't loose any sleep over it, but I might try to do something more efficient later in the week.

https://github.com/mittpat/DAEBlend/commit/305c1e5c8d9739255cb9a5311a7eed16db6e0a58

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A hard normal edge requires duplicating the position with a separate normal. In blender there is the auto smooth modifier which breaks edges based on a critical angle. I don't know if there is anything like 3ds max smoothing groups in blender. The exporter works with the vertex data it's given instead of generating geometry. I'll investigate when I get a chance later tonight if it's a configuration issue or see what's going on.

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Here's a test file with two cubes:

test file

Here's the exported DAE file rendered with FBX review

The cubes appear with correct lighting from the DAE file.

To get a flat lighting the edges need to be split with the "split modifier" or "split edge" command. Here is a cube corner with a single smoothing normal:

And here's the cube corner showing flat shading normals from splitting edges:

So it depends what you mean by a flat shaded cube. Using the "Shading: Smooth" button will have no effect on the export if all that button does in modify Blender's pixel shader without making changes to the geometry.

Regards,
Greg.

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Hi, thanks for the reply.

Yes custom split normals appear to work properly with DAEBlend,

However, using Blender 2.79 on Ubuntu, creating two cubes and smoothing one with the uvshading buttons with this visual result:

Once exported with the builtin exporter:
two_cubes-builtin.dae

Once exported with DAEBlend:
two_cubes-DAEblend.dae

As you can see, all the DAEBlend normals, for both cubes are at 45 degrees (-0.5773 -0.5773 -0.5773)
While the builtin exporter (OpenCollada) has the smooth cube normals at (-0.5773 -0.5773 -0.5773) but the hard cube normals at (1 0 0).

blend file:
two_cubes.blend

Thanks for putting your exporter on the web, it'a great help with Collada 1.5.0,

Pat

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Also, this post on the web may give a hint:

https://blender.stackexchange.com/questions/71356/vertex-normals-different-from-loop-normals

Quote:

data.calc_tessface();
for f in data.tessfaces:  # indices
    polygon = data.polygons[f.index] #Load Polygon

    for vert in range(len(f.vertices)):
        norm = data.vertices[f.vertices[vert]].normal
        norm1 = data.loops[polygon.vertices[vert]].normal
        print(norm, norm1)

<Vector (-0.5773, 0.5773, -0.5773)> <Vector (-1.0000, 0.0000, 0.0000)>
<Vector (-0.5773, -0.5773, -0.5773)> <Vector (-1.0000, 0.0000, 0.0000)>
<Vector (-0.5773, -0.5773, 0.5773)> <Vector (-1.0000, 0.0000, 0.0000)>
...

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The autosmooth option wasn't working so I fixed that. For a cube mesh, turn on the autosmooth checkbox under data tab and set angle < 90 degrees. That will now export sharp edges based on the angle limit. This exporter doesn't use the 'calc_normals()' api call, that will have to be done manually using the menu 'normals->recalculate outside/inside'.

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It is now working as you describe.

Thanks!

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