alphaMode not set on transparent materials

[donmccurdy]

When setting the alpha value of a material's baseColor to <1, I think we should default to alphaMode=BLEND. Currently the opacity value is written, but alphaMode is left blank, and defaults to OPAQUE. I can't see any equivalent to MASK on the Principled BSDF node, so I guess we can ignore that for now.

[donmccurdy]

Oops I missed the dropdown heh. Presumably this is what we should be using. 😅

[UX3D-nopper]

Did have a look at it. The entry exists in both versions, maybe assigned to different objects.

[donmccurdy]

Looks like a couple material properties currently not implemented:

glTF-Blender-IO/addons/io_scene_gltf2/blender/exp/gltf2_blender_gather_materials.py

Lines 78 to 88 in a05af66

	def __gather_alpha_cutoff(blender_material, export_settings):
	return None
	def __gather_alpha_mode(blender_material, export_settings):
	return None
	def __gather_double_sided(blender_material, export_settings):
	return None

• alpha_mode
• alpha_cutoff
• double_sided
• extras
• name

[julienduroure]

Is now merged with blender 2.8 repo