Fix T70666: FBX IO: Add support for new emission option of Principled BSDF.

3 files changed, 12 insertions, 5 deletions

diff --git a/io_scene_fbx/__init__.py b/io_scene_fbx/__init__.py
index 9257056c..bb0f8ae1 100644
--- a/io_scene_fbx/__init__.py
+++ b/io_scene_fbx/__init__.py
@@ -21,7 +21,7 @@
 bl_info = {
     "name": "FBX format",
     "author": "Campbell Barton, Bastien Montagne, Jens Restemeier",
-    "version": (4, 19, 0),
+    "version": (4, 20, 0),
     "blender": (2, 81, 6),
     "location": "File > Import-Export",
     "description": "FBX IO meshes, UV's, vertex colors, materials, textures, cameras, lamps and actions",
diff --git a/io_scene_fbx/export_fbx_bin.py b/io_scene_fbx/export_fbx_bin.py
index d1ba96bb..970fc721 100644
--- a/io_scene_fbx/export_fbx_bin.py
+++ b/io_scene_fbx/export_fbx_bin.py
@@ -1307,9 +1307,9 @@ def fbx_data_material_elements(root, ma, scene_data):
     elem_props_template_set(tmpl, props, "p_color", b"DiffuseColor", ma_wrap.base_color)
     # Not in Principled BSDF, so assuming always 1
     elem_props_template_set(tmpl, props, "p_number", b"DiffuseFactor", 1.0)
-    # Not in Principled BSDF, so assuming always 0
-    elem_props_template_set(tmpl, props, "p_color", b"EmissiveColor", ma_wrap.base_color)
-    elem_props_template_set(tmpl, props, "p_number", b"EmissiveFactor", 0.0)
+    # Principled BSDF only has an emissive color, so we assume factor to be always 1.0.
+    elem_props_template_set(tmpl, props, "p_color", b"EmissiveColor", ma_wrap.emission_color)
+    elem_props_template_set(tmpl, props, "p_number", b"EmissiveFactor", 1.0)
     # Not in Principled BSDF, so assuming always 0
     elem_props_template_set(tmpl, props, "p_color", b"AmbientColor", ambient_color)
     elem_props_template_set(tmpl, props, "p_number", b"AmbientFactor", 0.0)
@@ -1809,7 +1809,7 @@ PRINCIPLED_TEXTURE_SOCKETS_TO_FBX = (
     ("alpha_texture", b"TransparencyFactor"),  # Will be inverted in fact, not much we can do really...
     # ("base_color_texture", b"TransparentColor"),  # Uses diffuse color in Blender!
     # ("emit", "emit", b"EmissiveFactor"),
-    # ("diffuse", "diffuse", b"EmissiveColor"),  # Uses diffuse color in Blender!
+    ("emission_color_texture", b"EmissiveColor"),
     # ("ambient", "ambient", b"AmbientFactor"),
     # ("", "", b"AmbientColor"),  # World stuff in Blender, for now ignore...
     ("normalmap_texture", b"NormalMap"),
diff --git a/io_scene_fbx/import_fbx.py b/io_scene_fbx/import_fbx.py
index 9b8fbad1..93b01b9f 100644
--- a/io_scene_fbx/import_fbx.py
+++ b/io_scene_fbx/import_fbx.py
@@ -1427,6 +1427,10 @@ def blen_read_material(fbx_tmpl, fbx_obj, settings):
     # elem_props_get_color_rgb(fbx_props, b'ReflectionColor', const_color_white)
     # (x / 7.142) is only a guess, cycles usable range is (0.0 -> 0.5)
     ma_wrap.normalmap_strength = elem_props_get_number(fbx_props, b'BumpFactor', 2.5) / 7.142
+    # For emission color we can take into account the factor, but only for default values, not in case of texture.
+    emission_factor = elem_props_get_number(fbx_props, b'EmissiveFactor', 1.0)
+    ma_wrap.emission_color = [c * emission_factor
+                              for c in elem_props_get_color_rgb(fbx_props, b'EmissiveColor', const_color_black)]
 
     nodal_material_wrap_map[ma] = ma_wrap
 
@@ -3111,6 +3115,9 @@ def load(operator, context, filepath="",
                     elif lnk_type == b'Bump':
                         # TODO displacement...
                         """
+                    elif lnk_type in {b'EmissiveColor'}:
+                        ma_wrap.emission_color_texture.image = image
+                        texture_mapping_set(fbx_lnk, ma_wrap.emission_color_texture)
                     else:
                         print("WARNING: material link %r ignored" % lnk_type)