1 files changed, 131 insertions, 0 deletions
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_gather_material_normal_texture_info_class.py b/io_scene_gltf2/blender/exp/gltf2_blender_gather_material_normal_texture_info_class.py
new file mode 100755
index 00000000..3d78a478
--- /dev/null
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_material_normal_texture_info_class.py
@@ -0,0 +1,131 @@
+# Copyright 2018 The glTF-Blender-IO authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import bpy
+import typing
+from io_scene_gltf2.blender.exp.gltf2_blender_gather_cache import cached
+from io_scene_gltf2.io.com import gltf2_io
+from io_scene_gltf2.blender.exp import gltf2_blender_gather_texture
+from io_scene_gltf2.blender.exp import gltf2_blender_search_node_tree
+from io_scene_gltf2.blender.exp import gltf2_blender_export_keys
+from io_scene_gltf2.blender.exp import gltf2_blender_get
+from io_scene_gltf2.io.com.gltf2_io_extensions import Extension
+
+
+@cached
+def gather_material_normal_texture_info_class(blender_shader_sockets_or_texture_slots: typing.Union[
+    typing.Tuple[bpy.types.NodeSocket], typing.Tuple[bpy.types.Texture]],
+        export_settings):
+    if not __filter_texture_info(blender_shader_sockets_or_texture_slots, export_settings):
+        return None
+
+    texture_info = gltf2_io.MaterialNormalTextureInfoClass(
+        extensions=__gather_extensions(blender_shader_sockets_or_texture_slots, export_settings),
+        extras=__gather_extras(blender_shader_sockets_or_texture_slots, export_settings),
+        scale=__gather_scale(blender_shader_sockets_or_texture_slots, export_settings),
+        index=__gather_index(blender_shader_sockets_or_texture_slots, export_settings),
+        tex_coord=__gather_tex_coord(blender_shader_sockets_or_texture_slots, export_settings)
+    )
+
+    return texture_info
+
+
+def __filter_texture_info(blender_shader_sockets_or_texture_slots, export_settings):
+    if not blender_shader_sockets_or_texture_slots:
+        return False
+    if not all([elem is not None for elem in blender_shader_sockets_or_texture_slots]):
+        return False
+    if isinstance(blender_shader_sockets_or_texture_slots[0], bpy.types.NodeSocket):
+        if any([__get_tex_from_socket(socket) is None for socket in blender_shader_sockets_or_texture_slots]):
+            # sockets do not lead to a texture --> discard
+            return False
+    return True
+
+
+def __gather_extensions(blender_shader_sockets_or_texture_slots, export_settings):
+    if not export_settings[gltf2_blender_export_keys.TEXTURE_TRANSFORM]:
+        return None
+
+    normal_map_node = blender_shader_sockets_or_texture_slots[0].links[0].from_node
+    if not isinstance(normal_map_node, bpy.types.ShaderNodeNormalMap):
+        return None
+
+    texture_socket = normal_map_node.inputs["Color"]
+    if len(texture_socket.links) == 0:
+        return None
+
+    texture_node = texture_socket.links[0].from_node
+    texture_transform = gltf2_blender_get.get_texture_transform_from_texture_node(texture_node)
+
+    extension = Extension("KHR_texture_transform", texture_transform)
+    return {"KHR_texture_transform": extension}
+
+
+def __gather_extras(blender_shader_sockets_or_texture_slots, export_settings):
+    return None
+
+
+def __gather_scale(blender_shader_sockets_or_texture_slots, export_settings):
+    return None
+
+
+def __gather_index(blender_shader_sockets_or_texture_slots, export_settings):
+    # We just put the actual shader into the 'index' member
+    return gltf2_blender_gather_texture.gather_texture(blender_shader_sockets_or_texture_slots, export_settings)
+
+
+def __gather_tex_coord(blender_shader_sockets_or_texture_slots, export_settings):
+    if __is_socket(blender_shader_sockets_or_texture_slots):
+        blender_shader_node = __get_tex_from_socket(blender_shader_sockets_or_texture_slots[0]).shader_node
+        if len(blender_shader_node.inputs['Vector'].links) == 0:
+            return 0
+
+        input_node = blender_shader_node.inputs['Vector'].links[0].from_node
+
+        if isinstance(input_node, bpy.types.ShaderNodeMapping):
+
+            if len(input_node.inputs['Vector'].links) == 0:
+                return 0
+
+            input_node = input_node.inputs['Vector'].links[0].from_node
+
+        if not isinstance(input_node, bpy.types.ShaderNodeUVMap):
+            return 0
+
+        if input_node.uv_map == '':
+            return 0
+
+        # Try to gather map index.
+        for blender_mesh in bpy.data.meshes:
+            texCoordIndex = blender_mesh.uv_layers.find(input_node.uv_map)
+            if texCoordIndex >= 0:
+                return texCoordIndex
+
+        return 0
+    else:
+        raise NotImplementedError()
+
+
+def __is_socket(sockets_or_slots):
+    return isinstance(sockets_or_slots[0], bpy.types.NodeSocket)
+
+
+def __get_tex_from_socket(socket):
+    result = gltf2_blender_search_node_tree.from_socket(
+        socket,
+        gltf2_blender_search_node_tree.FilterByType(bpy.types.ShaderNodeTexImage))
+    if not result:
+        return None
+    return result[0]
+