glTF exporter: code refactoring - remove primitive splitting

1 files changed, 7 insertions, 195 deletions

diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_extract.py b/io_scene_gltf2/blender/exp/gltf2_blender_extract.py
index bce1d60f..8a3b5195 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_extract.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_extract.py
@@ -605,6 +605,7 @@ def extract_primitives(glTF, blender_mesh, blender_object, blender_vertex_groups
             triangles = tessellate_polygon((polyline,))
 
             for triangle in triangles:
+
                 for triangle_index in triangle:
                     loop_index_list.append(blender_polygon.loop_indices[triangle_index])
         else:
@@ -961,203 +962,14 @@ def extract_primitives(glTF, blender_mesh, blender_object, blender_vertex_groups
                         attributes[target_tangent_id].extend(target_tangents[morph_index])
 
     #
-    # Add primitive plus split them if needed.
+    # Add non-empty primitives
     #
 
-    result_primitives = []
-
-    for material_idx, primitive in material_idx_to_primitives.items():
-        export_color = True
-
-        #
-
-        indices = primitive[INDICES_ID]
-
-        if len(indices) == 0:
-            continue
-
-        position = primitive[ATTRIBUTES_ID][POSITION_ATTRIBUTE]
-        normal = primitive[ATTRIBUTES_ID][NORMAL_ATTRIBUTE]
-        if use_tangents:
-            tangent = primitive[ATTRIBUTES_ID][TANGENT_ATTRIBUTE]
-        tex_coords = []
-        for tex_coord_index in range(0, tex_coord_max):
-            tex_coords.append(primitive[ATTRIBUTES_ID][TEXCOORD_PREFIX + str(tex_coord_index)])
-        colors = []
-        if export_color:
-            for color_index in range(0, color_max):
-                colors.append(primitive[ATTRIBUTES_ID][COLOR_PREFIX + str(color_index)])
-        joints = []
-        weights = []
-        if export_settings[gltf2_blender_export_keys.SKINS]:
-            for bone_index in range(0, bone_max):
-                joints.append(primitive[ATTRIBUTES_ID][JOINTS_PREFIX + str(bone_index)])
-                weights.append(primitive[ATTRIBUTES_ID][WEIGHTS_PREFIX + str(bone_index)])
-
-        target_positions = []
-        target_normals = []
-        target_tangents = []
-        if export_settings[gltf2_blender_export_keys.MORPH]:
-            for morph_index in range(0, morph_max):
-                target_positions.append(primitive[ATTRIBUTES_ID][MORPH_POSITION_PREFIX + str(morph_index)])
-                target_normals.append(primitive[ATTRIBUTES_ID][MORPH_NORMAL_PREFIX + str(morph_index)])
-                if use_tangents:
-                    target_tangents.append(primitive[ATTRIBUTES_ID][MORPH_TANGENT_PREFIX + str(morph_index)])
-
-        #
-
-        count = len(indices)
-
-        if count == 0:
-            continue
-
-        max_index = max(indices)
-
-        #
-
-        # NOTE: Values used by some graphics APIs as "primitive restart" values are disallowed.
-        # Specifically, the value 65535 (in UINT16) cannot be used as a vertex index.
-        # https://github.com/KhronosGroup/glTF/issues/1142
-        # https://github.com/KhronosGroup/glTF/pull/1476/files
-
-        range_indices = 65535
-
-        #
-
-        if max_index >= range_indices:
-            #
-            # Splitting result_primitives.
-            #
-
-            # At start, all indices are pending.
-            pending_attributes = {
-                POSITION_ATTRIBUTE: [],
-                NORMAL_ATTRIBUTE: []
-            }
-
-            if use_tangents:
-                pending_attributes[TANGENT_ATTRIBUTE] = []
-
-            pending_primitive = {
-                MATERIAL_ID: material_idx,
-                INDICES_ID: [],
-                ATTRIBUTES_ID: pending_attributes
-            }
-
-            pending_primitive[INDICES_ID].extend(indices)
-
-            pending_attributes[POSITION_ATTRIBUTE].extend(position)
-            pending_attributes[NORMAL_ATTRIBUTE].extend(normal)
-            if use_tangents:
-                pending_attributes[TANGENT_ATTRIBUTE].extend(tangent)
-            tex_coord_index = 0
-            for tex_coord in tex_coords:
-                pending_attributes[TEXCOORD_PREFIX + str(tex_coord_index)] = tex_coord
-                tex_coord_index += 1
-            if export_color:
-                color_index = 0
-                for color in colors:
-                    pending_attributes[COLOR_PREFIX + str(color_index)] = color
-                    color_index += 1
-            if export_settings[gltf2_blender_export_keys.SKINS]:
-                joint_index = 0
-                for joint in joints:
-                    pending_attributes[JOINTS_PREFIX + str(joint_index)] = joint
-                    joint_index += 1
-                weight_index = 0
-                for weight in weights:
-                    pending_attributes[WEIGHTS_PREFIX + str(weight_index)] = weight
-                    weight_index += 1
-            if export_settings[gltf2_blender_export_keys.MORPH]:
-                morph_index = 0
-                for target_position in target_positions:
-                    pending_attributes[MORPH_POSITION_PREFIX + str(morph_index)] = target_position
-                    morph_index += 1
-                morph_index = 0
-                for target_normal in target_normals:
-                    pending_attributes[MORPH_NORMAL_PREFIX + str(morph_index)] = target_normal
-                    morph_index += 1
-                if use_tangents:
-                    morph_index = 0
-                    for target_tangent in target_tangents:
-                        pending_attributes[MORPH_TANGENT_PREFIX + str(morph_index)] = target_tangent
-                        morph_index += 1
-
-            pending_indices = pending_primitive[INDICES_ID]
-
-            # Continue until all are processed.
-            while len(pending_indices) > 0:
-
-                process_indices = pending_primitive[INDICES_ID]
-                max_index = max(process_indices)
-
-                pending_indices = []
-
-                #
-                #
-
-                all_local_indices = []
-
-                for i in range(0, (max_index // range_indices) + 1):
-                    all_local_indices.append([])
-
-                #
-                #
-
-                # For all faces ...
-                for face_index in range(0, len(process_indices), 3):
-
-                    written = False
-
-                    face_min_index = min(process_indices[face_index + 0], process_indices[face_index + 1],
-                                         process_indices[face_index + 2])
-                    face_max_index = max(process_indices[face_index + 0], process_indices[face_index + 1],
-                                         process_indices[face_index + 2])
-
-                    # ... check if it can be but in a range of maximum indices.
-                    for i in range(0, (max_index // range_indices) + 1):
-                        offset = i * range_indices
-
-                        # Yes, so store the primitive with its indices.
-                        if face_min_index >= offset and face_max_index < offset + range_indices:
-                            all_local_indices[i].extend(
-                                [process_indices[face_index + 0], process_indices[face_index + 1],
-                                 process_indices[face_index + 2]])
-
-                            written = True
-                            break
-
-                    # If not written, the triangle face has indices from different ranges.
-                    if not written:
-                        pending_indices.extend([process_indices[face_index + 0], process_indices[face_index + 1],
-                                                process_indices[face_index + 2]])
-
-                # Only add result_primitives, which do have indices in it.
-                for local_indices in all_local_indices:
-                    if len(local_indices) > 0:
-                        current_primitive = extract_primitive_floor(pending_primitive, local_indices, use_tangents)
-
-                        result_primitives.append(current_primitive)
-
-                        print_console('DEBUG', 'Adding primitive with splitting. Indices: ' + str(
-                            len(current_primitive[INDICES_ID])) + ' Vertices: ' + str(
-                            len(current_primitive[ATTRIBUTES_ID][POSITION_ATTRIBUTE]) // 3))
-
-                # Process primitive faces having indices in several ranges.
-                if len(pending_indices) > 0:
-                    pending_primitive = extract_primitive_pack(pending_primitive, pending_indices, use_tangents)
-
-                    print_console('DEBUG', 'Creating temporary primitive for splitting')
-
-        else:
-            #
-            # No splitting needed.
-            #
-            result_primitives.append(primitive)
-
-            print_console('DEBUG', 'Adding primitive without splitting. Indices: ' + str(
-                len(primitive[INDICES_ID])) + ' Vertices: ' + str(
-                len(primitive[ATTRIBUTES_ID][POSITION_ATTRIBUTE]) // 3))
+    result_primitives = [
+        primitive
+        for primitive in material_idx_to_primitives.values()
+        if len(primitive[INDICES_ID]) != 0
+    ]
 
     print_console('INFO', 'Primitives created: ' + str(len(result_primitives)))