From: Mikko Rasa <tdb@tdb.fi>
Date: Tue, 13 Apr 2021 09:43:56 +0000 (+0300)
Subject: Use unit 0 UVs for exporting TBNs if no UV layer is specified
X-Git-Url: http://git.tdb.fi/?p=libs%2Fgl.git;a=commitdiff_plain;h=8350e7ba2b75f6a5325e7097a3a956661cb4b3b7

Use unit 0 UVs for exporting TBNs if no UV layer is specified
---

diff --git a/blender/io_mspgl/mesh.py b/blender/io_mspgl/mesh.py
index 8f19676a..754e6ffc 100644
--- a/blender/io_mspgl/mesh.py
+++ b/blender/io_mspgl/mesh.py
@@ -451,10 +451,15 @@ class Mesh:
 		# remains intact for TBN vector computation
 		tbn_layer_index = -1
 		if self.tbn_vecs:
-			uv_names = [u.name for u in self.uv_layers]
-			if self.tbn_uvtex in uv_names:
+			if self.tbn_uvtex:
+				uv_names = [u.name for u in self.uv_layers]
+				if self.tbn_uvtex in uv_names:
+					tbn_layer_index = uv_names.index(self.tbn_uvtex)
+			elif self.uv_layers[0].unit==0:
+				tbn_layer_index = 0
+
+			if tbn_layer_index>=0:
 				prog_count += 1
-				tbn_layer_index = uv_names.index(self.tbn_uvtex)
 				progress.push_task_slice("Computing TBN", 0, prog_count)
 				self.split_vertices(self.find_uv_group, progress, tbn_layer_index)
 				progress.set_task_slice(self.tbn_uvtex, 1, prog_count)