ui.py

        bkit_ratings = asset.bkit_ratings

        t = time.time() - ui.last_rating_time
        if bpy.context.mode in ('SCULPT', 'PAINT_TEXTURE'):
            accept_value = 'PRESS'
        else:
            accept_value = 'RELEASE'

        if ui.rating_button_on and event.type == 'LEFTMOUSE' and event.value == accept_value:
            if mouse_in_area(mx, my,
                             ui.rating_x,
                             ui.rating_y - ui.rating_button_width,
                             ui.rating_button_width * 2,
                             ui.rating_button_width):
                ui.rating_menu_on = True
                ui.rating_button_on = False
                return True
        if ui.rating_menu_on:
            if mouse_in_area(mx, my,
                             ui.rating_x,
                             ui.rating_y - ui.rating_ui_height,
                             ui.rating_ui_width,
                             ui.rating_ui_height + 25):
                rmx = mx - (ui.rating_x)
                rmy = my - (ui.rating_y - ui.rating_ui_height)

                # quality
                upload_rating = False
                if (ui.quality_stars_x < rmx and rmx < ui.quality_stars_x + 10 * ui.star_size and \
                    ui.quality_stars_y < rmy and rmy < ui.quality_stars_y + ui.star_size and event.type == 'LEFTMOUSE' and event.value == 'PRESS') or \
                        ui.dragging_rating_quality:

                    if event.type == 'LEFTMOUSE':
                        if event.value == 'PRESS':
                            ui.dragging_rating = True
                            ui.dragging_rating_quality = True
                        elif event.value == 'RELEASE':
                            ui.dragging_rating = False
                            ui.dragging_rating_quality = False

                    if ui.dragging_rating_quality:
                        q = math.ceil((rmx - ui.quality_stars_x) / (float(ui.star_size)))
                        bkit_ratings.rating_quality = q

                # work hours
                if (
                        ui.workhours_bar_x < rmx and rmx < ui.workhours_bar_x + ui.workhours_bar_x_max + ui.workhours_bar_slider_size and \
                        ui.workhours_bar_y < rmy and rmy < ui.workhours_bar_y + ui.workhours_bar_slider_size and event.type == 'LEFTMOUSE' and event.value == 'PRESS') \
                        or (ui.dragging_rating_work_hours):
                    if event.value == 'PRESS':
                        ui.dragging_rating = True
                        ui.dragging_rating_work_hours = True
                    elif event.value == 'RELEASE':
                        ui.dragging_rating = False
                        ui.dragging_rating_work_hours = False
                    if ui.dragging_rating_work_hours:
                        xv = rmx - ui.workhours_bar_x - ui.workhours_bar_slider_size / 2
                        ratio = xv / ui.workhours_bar_x_max
                        if asset_data['asset_type'] == 'model':
                            wh_log2 = ratio * 9 - 1
                            wh = 2 ** wh_log2
                        else:
                            wh = 5 * ratio
                        bkit_ratings.rating_work_hours = wh

                if event.type == 'LEFTMOUSE' and event.value == 'RELEASE':
                    if bkit_ratings.rating_quality > 0.1 or bkit_ratings.rating_work_hours > 0.1:
                        ratings.upload_rating(asset)
                    ui.last_rating_time = time.time()
                return True
            else:
                ui.rating_button_on = True
                ui.rating_menu_on = False
    return False


def mouse_in_area(mx, my, x, y, w, h):
    if x < mx < x + w and y < my < y + h:
        return True
    else:
        return False


def mouse_in_asset_bar(mx, my):
    ui_props = bpy.context.scene.blenderkitUI
    if ui_props.bar_y - ui_props.bar_height < my < ui_props.bar_y \
            and mx > ui_props.bar_x and mx < ui_props.bar_x + ui_props.bar_width:
        return True
    else:
        return False


def mouse_in_region(r, mx, my):
    if 0 < my < r.height and 0 < mx < r.width:
        return True
    else:
        return False


def update_ui_size(area, region):
    ui = bpy.context.scene.blenderkitUI
    user_preferences = bpy.context.preferences.addons['blenderkit'].preferences
    ui_scale = bpy.context.preferences.view.ui_scale

    ui.margin = ui.bl_rna.properties['margin'].default * ui_scale
    ui.thumb_size = ui.bl_rna.properties['thumb_size'].default * ui_scale

    reg_multiplier = 1
    if not bpy.context.preferences.system.use_region_overlap:
        reg_multiplier = 0

    for r in area.regions:
        if r.type == 'TOOLS':
            ui.bar_x = r.width * reg_multiplier + ui.margin + ui.bar_x_offset * ui_scale
        elif r.type == 'UI':
            ui.bar_end = r.width * reg_multiplier + 100 * ui_scale

    ui.bar_width = region.width - ui.bar_x - ui.bar_end
    ui.wcount = math.floor(
        (ui.bar_width - 2 * ui.drawoffset) / (ui.thumb_size + ui.margin))

    search_results = bpy.context.scene.get('search results')
    if search_results != None:
        ui.hcount = min(user_preferences.max_assetbar_rows, math.ceil(len(search_results) / ui.wcount))
    else:
        ui.hcount = 1
    ui.bar_height = (ui.thumb_size + ui.margin) * ui.hcount + ui.margin
    ui.bar_y = region.height - ui.bar_y_offset * ui_scale
    if ui.down_up == 'UPLOAD':
        ui.reports_y = ui.bar_y - 600
        ui.reports_x = ui.bar_x
    else:
        ui.reports_y = ui.bar_y - ui.bar_height - 100
        ui.reports_x = ui.bar_x

    ui.rating_x = ui.bar_x
    ui.rating_y = ui.bar_y - ui.bar_height


class AssetBarOperator(bpy.types.Operator):
    '''runs search and displays the asset bar at the same time'''
    bl_idname = "view3d.blenderkit_asset_bar"
    bl_label = "BlenderKit Asset Bar UI"
    bl_options = {'REGISTER', 'UNDO'}

    do_search: BoolProperty(name="Run Search", description='', default=True, options={'SKIP_SAVE'})
    keep_running: BoolProperty(name="Keep Running", description='', default=True, options={'SKIP_SAVE'})
    free_only: BoolProperty(name="Free Only", description='', default=False, options={'SKIP_SAVE'})

    category: StringProperty(
        name="Category",
        description="search only subtree of this category",
        default="", options={'SKIP_SAVE'})

    def search_more(self):
        sro = bpy.context.scene.get('search results orig')
        if sro is not None and sro.get('next') is not None:
            search.search(get_next=True)

    def exit_modal(self):
        try:
            bpy.types.SpaceView3D.draw_handler_remove(self._handle_2d, 'WINDOW')
            bpy.types.SpaceView3D.draw_handler_remove(self._handle_3d, 'WINDOW')
        except:
            pass;
        ui_props = bpy.context.scene.blenderkitUI

        ui_props.dragging = False
        ui_props.tooltip = ''
        ui_props.active_index = -3
        ui_props.draw_drag_image = False
        ui_props.draw_snapped_bounds = False
        ui_props.has_hit = False
        ui_props.assetbar_on = False

    def modal(self, context, event):
        # This is for case of closing the area or changing type:
        ui_props = context.scene.blenderkitUI
        user_preferences = bpy.context.preferences.addons['blenderkit'].preferences

        areas = []

        for w in context.window_manager.windows:
            areas.extend(w.screen.areas)
        if bpy.context.scene != self.scene:
            self.exit_modal()
            ui_props.assetbar_on = False
            return {'CANCELLED'}

        if self.area not in areas or self.area.type != 'VIEW_3D':
            # print('search areas')
            # stopping here model by now - because of:
            #   switching layouts or maximizing area now fails to assign new area throwing the bug
            #   internal error: modal gizmo-map handler has invalid area
            self.exit_modal()
            ui_props.assetbar_on = False
            return {'CANCELLED'}

            newarea = None
            for a in context.window.screen.areas:
                if a.type == 'VIEW_3D':
                    self.area = a
                    for r in a.regions:
                        if r.type == 'WINDOW':
                            self.region = r
                    newarea = a
                    break;
                    # context.area = a

            # we check again and quit if things weren't fixed this way.
            if newarea == None:
                self.exit_modal()
                ui_props.assetbar_on = False
                return {'CANCELLED'}

        update_ui_size(self.area, self.region)

        search.timer_update()
        download.timer_update()
        bg_blender.bg_update()

        if context.region != self.region:
            return {'PASS_THROUGH'}

        # this was here to check if sculpt stroke is running, but obviously that didn't help,
        #  since the RELEASE event is cought by operator and thus there is no way to detect a stroke has ended...
        if bpy.context.mode in ('SCULPT', 'PAINT_TEXTURE'):
            if event.type == 'MOUSEMOVE':  # ASSUME THAT SCULPT OPERATOR ACTUALLY STEALS THESE EVENTS,
                # SO WHEN THERE ARE SOME WE CAN APPEND BRUSH...
                bpy.context.window_manager['appendable'] = True
            if event.type == 'LEFTMOUSE':
                if event.value == 'PRESS':
                    bpy.context.window_manager['appendable'] = False

        self.area.tag_redraw()
        s = context.scene

        if ui_props.turn_off:
            ui_props.assetbar_on = False
            ui_props.turn_off = False
            self.exit_modal()
            ui_props.draw_tooltip = False
            return {'CANCELLED'}

        if ui_props.down_up == 'UPLOAD':

            ui_props.mouse_x = 0
            ui_props.mouse_y = self.region.height

            mx = event.mouse_x
            my = event.mouse_y

            ui_props.draw_tooltip = True

            # only generate tooltip once in a while
            if (
                    event.type == 'LEFTMOUSE' or event.type == 'RIGHTMOUSE') and event.value == 'RELEASE' or event.type == 'ENTER' or ui_props.tooltip == '':
                ao = bpy.context.active_object
                if ui_props.asset_type == 'MODEL' and ao != None \
                        or ui_props.asset_type == 'MATERIAL' and ao != None and ao.active_material != None \
                        or ui_props.asset_type == 'BRUSH':
                    export_data, upload_data, eval_path_computing, eval_path_state, eval_path, props = upload.get_upload_data(
                        self,
                        context,
                        ui_props.asset_type)
                    ui_props.tooltip = search.generate_tooltip(upload_data)

            return {'PASS_THROUGH'}

        # TODO add one more condition here to take less performance.
        r = self.region
        s = bpy.context.scene
        sr = s.get('search results')

        # If there aren't any results, we need no interaction(yet)
        if sr is None:
            return {'PASS_THROUGH'}
        if len(sr) - ui_props.scrolloffset < (ui_props.wcount * ui_props.hcount) + 10:
            self.search_more()
        if event.type == 'WHEELUPMOUSE' or event.type == 'WHEELDOWNMOUSE' or event.type == 'TRACKPADPAN':
            # scrolling
            mx = event.mouse_region_x
            my = event.mouse_region_y

            if ui_props.dragging and not mouse_in_asset_bar(mx, my):  # and my < r.height - ui_props.bar_height \
                # and mx > 0 and mx < r.width and my > 0:
                sprops = bpy.context.scene.blenderkit_models
                if event.type == 'WHEELUPMOUSE':
                    sprops.offset_rotation_amount += sprops.offset_rotation_step
                elif event.type == 'WHEELDOWNMOUSE':
                    sprops.offset_rotation_amount -= sprops.offset_rotation_step

                #### TODO - this snapping code below is 3x in this file.... refactor it.
                ui_props.has_hit, ui_props.snapped_location, ui_props.snapped_normal, ui_props.snapped_rotation, face_index, object, matrix = mouse_raycast(
                    context, mx, my)

                # MODELS can be dragged on scene floor
                if not ui_props.has_hit and ui_props.asset_type == 'MODEL':
                    ui_props.has_hit, ui_props.snapped_location, ui_props.snapped_normal, ui_props.snapped_rotation, face_index, object, matrix = floor_raycast(
                        context,
                        mx, my)

                return {'RUNNING_MODAL'}

            if not mouse_in_asset_bar(mx, my):
                return {'PASS_THROUGH'}

            # note - TRACKPADPAN is unsupported in blender by now.
            # if event.type == 'TRACKPADPAN' :
            #     print(dir(event))
            #     print(event.value, event.oskey, event.)
            if (event.type == 'WHEELDOWNMOUSE') and len(sr) - ui_props.scrolloffset > ui_props.wcount:
                ui_props.scrolloffset += 1

            if event.type == 'WHEELUPMOUSE' and ui_props.scrolloffset > 0:
                ui_props.scrolloffset -= 1
            return {'RUNNING_MODAL'}
        if event.type == 'MOUSEMOVE':  # Apply

            r = self.region
            mx = event.mouse_region_x
            my = event.mouse_region_y

            ui_props.mouse_x = mx
            ui_props.mouse_y = my

            if ui_props.dragging_rating or ui_props.rating_menu_on:
                res = interact_rating(r, mx, my, event)
                if res == True:
                    return {'RUNNING_MODAL'}

            if ui_props.drag_init:
                ui_props.drag_length += 1
                if ui_props.drag_length > 0:
                    ui_props.dragging = True
                    ui_props.drag_init = False

            if not (ui_props.dragging and mouse_in_region(r, mx, my)) and not mouse_in_asset_bar(mx, my):
                ui_props.active_index = -3
                ui_props.draw_tooltip = False
                bpy.context.window.cursor_set("DEFAULT")
                return {'PASS_THROUGH'}

            sr = bpy.context.scene['search results']

            if not ui_props.dragging:
                bpy.context.window.cursor_set("DEFAULT")

                if sr != None and ui_props.wcount * ui_props.hcount > len(sr) and ui_props.scrolloffset > 0:
                    ui_props.scrolloffset = 0

                asset_search_index = get_asset_under_mouse(mx, my)
                ui_props.active_index = asset_search_index
                if asset_search_index > -1:

                    asset_data = sr[asset_search_index]
                    ui_props.draw_tooltip = True

                    ui_props.tooltip = asset_data['tooltip']
                else:
                    ui_props.draw_tooltip = False

                if mx > ui_props.bar_x + ui_props.bar_width - 50 and len(sr) - ui_props.scrolloffset > (
                        ui_props.wcount * ui_props.hcount):
                    ui_props.active_index = -1
                    return {'RUNNING_MODAL'}
                if mx < ui_props.bar_x + 50 and ui_props.scrolloffset > 0:
                    ui_props.active_index = -2
                    return {'RUNNING_MODAL'}

            else:
                result = False
                if ui_props.dragging and not mouse_in_asset_bar(mx, my) and mouse_in_region(r, mx, my):
                    ui_props.has_hit, ui_props.snapped_location, ui_props.snapped_normal, ui_props.snapped_rotation, face_index, object, matrix = mouse_raycast(
                        context, mx, my)
                    # MODELS can be dragged on scene floor
                    if not ui_props.has_hit and ui_props.asset_type == 'MODEL':
                        ui_props.has_hit, ui_props.snapped_location, ui_props.snapped_normal, ui_props.snapped_rotation, face_index, object, matrix = floor_raycast(
                            context,
                            mx, my)
                if ui_props.has_hit and ui_props.asset_type == 'MODEL':
                    # this condition is here to fix a bug for a scene submitted by a user, so this situation shouldn't
                    # happen anymore, but there might exists scenes which have this problem for some reason.
                    if ui_props.active_index < len(sr) and ui_props.active_index > -1:
                        ui_props.draw_snapped_bounds = True
                        active_mod = sr[ui_props.active_index]
                        ui_props.snapped_bbox_min = Vector(active_mod['bbox_min'])
                        ui_props.snapped_bbox_max = Vector(active_mod['bbox_max'])

                else:
                    ui_props.draw_snapped_bounds = False
                    ui_props.draw_drag_image = True
            return {'RUNNING_MODAL'}

        if event.type == 'LEFTMOUSE':

            r = self.region
            mx = event.mouse_x - r.x
            my = event.mouse_y - r.y

            ui_props = context.scene.blenderkitUI
            if event.value == 'PRESS' and ui_props.active_index > -1:
                if ui_props.asset_type == 'MODEL' or ui_props.asset_type == 'MATERIAL':
                    ui_props.drag_init = True
                    bpy.context.window.cursor_set("NONE")
                    ui_props.draw_tooltip = False
                    ui_props.drag_length = 0

            if ui_props.rating_on:
                res = interact_rating(r, mx, my, event)
                if res:
                    return {'RUNNING_MODAL'}

            if not ui_props.dragging and not mouse_in_asset_bar(mx, my):
                return {'PASS_THROUGH'}

            # this can happen by switching result asset types - length of search result changes
            if ui_props.scrolloffset > 0 and (ui_props.wcount * ui_props.hcount) > len(sr) - ui_props.scrolloffset:
                ui_props.scrolloffset = len(sr) - (ui_props.wcount * ui_props.hcount)

            if event.value == 'RELEASE':  # Confirm
                ui_props.drag_init = False

                # scroll by a whole page
                if mx > ui_props.bar_x + ui_props.bar_width - 50 and len(
                        sr) - ui_props.scrolloffset > ui_props.wcount * ui_props.hcount:
                    ui_props.scrolloffset = min(
                        ui_props.scrolloffset + (ui_props.wcount * ui_props.hcount),
                        len(sr) - ui_props.wcount * ui_props.hcount)
                    return {'RUNNING_MODAL'}
                if mx < ui_props.bar_x + 50 and ui_props.scrolloffset > 0:
                    ui_props.scrolloffset = max(0, ui_props.scrolloffset - ui_props.wcount * ui_props.hcount)
                    return {'RUNNING_MODAL'}

                # Drag-drop interaction
                if ui_props.dragging and mouse_in_region(r, mx, my):
                    asset_search_index = ui_props.active_index
                    # raycast here
                    ui_props.active_index = -3

                    if ui_props.asset_type == 'MODEL':

                        ui_props.has_hit, ui_props.snapped_location, ui_props.snapped_normal, ui_props.snapped_rotation, face_index, object, matrix = mouse_raycast(
                            context, mx, my)

                        # MODELS can be dragged on scene floor
                        if not ui_props.has_hit and ui_props.asset_type == 'MODEL':
                            ui_props.has_hit, ui_props.snapped_location, ui_props.snapped_normal, ui_props.snapped_rotation, face_index, object, matrix = floor_raycast(
                                context,
                                mx, my)

                        if not ui_props.has_hit:
                            return {'RUNNING_MODAL'}

                        target_object = ''
                        if object is not None:
                            target_object = object.name
                        target_slot = ''

                    if ui_props.asset_type == 'MATERIAL':
                        ui_props.has_hit, ui_props.snapped_location, ui_props.snapped_normal, ui_props.snapped_rotation, face_index, object, matrix = mouse_raycast(
                            context, mx, my)

                        if not ui_props.has_hit:
                            # this is last attempt to get object under mouse - for curves and other objects than mesh.
                            ui_props.dragging = False
                            sel = utils.selection_get()
                            bpy.ops.view3d.select(location=(event.mouse_region_x, event.mouse_region_y))
                            sel1 = utils.selection_get()
                            if sel[0] != sel1[0] and sel1[0].type != 'MESH':
                                object = sel1[0]
                                target_slot = sel1[0].active_material_index
                                ui_props.has_hit = True
                            utils.selection_set(sel)

                        if not ui_props.has_hit:
                            return {'RUNNING_MODAL'}

                        else:
                            # first, test if object can have material applied.
                            if object is not None and not object.is_library_indirect:
                                target_object = object.name
                                # create final mesh to extract correct material slot
                                depsgraph = bpy.context.evaluated_depsgraph_get()
                                object_eval = object.evaluated_get(depsgraph)
                                temp_mesh = object_eval.to_mesh()
                                target_slot = temp_mesh.polygons[face_index].material_index
                                object_eval.to_mesh_clear()
                            else:
                                self.report({'WARNING'}, "Invalid or library object as input:")
                                target_object = ''
                                target_slot = ''

                # Click interaction
                else:
                    asset_search_index = get_asset_under_mouse(mx, my)

                    if ui_props.asset_type in ('MATERIAL',
                                               'MODEL'):  # this was meant for particles, commenting for now or ui_props.asset_type == 'MODEL':
                        ao = bpy.context.active_object
                        if ao != None and not ao.is_library_indirect:
                            target_object = bpy.context.active_object.name
                            target_slot = bpy.context.active_object.active_material_index
                        else:
                            target_object = ''
                            target_slot = ''
                # FIRST START SEARCH

                if asset_search_index == -3:
                    return {'RUNNING_MODAL'}
                if asset_search_index > -3:
                    if ui_props.asset_type == 'MATERIAL':
                        if target_object != '':
                            # position is for downloader:
                            loc = ui_props.snapped_location
                            rotation = (0, 0, 0)

                            asset_data = sr[asset_search_index]
                            utils.automap(target_object, target_slot=target_slot,
                                          tex_size=asset_data.get('texture_size_meters', 1.0))
                            bpy.ops.scene.blenderkit_download(True,
                                                              asset_type=ui_props.asset_type,
                                                              asset_index=asset_search_index,
                                                              model_location=loc,
                                                              model_rotation=rotation,
                                                              target_object=target_object,
                                                              material_target_slot=target_slot)


                    elif ui_props.asset_type == 'MODEL':
                        if ui_props.has_hit and ui_props.dragging:
                            loc = ui_props.snapped_location
                            rotation = ui_props.snapped_rotation
                        else:
                            loc = s.cursor.location
                            rotation = s.cursor.rotation_euler

                        bpy.ops.scene.blenderkit_download(True,
                                                          asset_type=ui_props.asset_type,
                                                          asset_index=asset_search_index,
                                                          model_location=loc,
                                                          model_rotation=rotation,
                                                          target_object=target_object)

                    else:
                        bpy.ops.scene.blenderkit_download(asset_type=ui_props.asset_type,
                                                          asset_index=asset_search_index)

                    ui_props.dragging = False
                    return {'RUNNING_MODAL'}
            else:
                return {'RUNNING_MODAL'}

        if event.type == 'W' and ui_props.active_index != -3:
            sr = bpy.context.scene['search results']
            asset_data = sr[ui_props.active_index]
            a = bpy.context.window_manager['bkit authors'].get(asset_data['author_id'])
            if a is not None:
                utils.p('author:', a)
                if a.get('aboutMeUrl') is not None:
                    bpy.ops.wm.url_open(url=a['aboutMeUrl'])
            return {'RUNNING_MODAL'}
        if event.type == 'A' and ui_props.active_index != -3:
            sr = bpy.context.scene['search results']
            asset_data = sr[ui_props.active_index]
            a = asset_data['author_id']
            if a is not None:
                utils.p('author:', a)
                search.search(author_id=a)
            return {'RUNNING_MODAL'}
        if event.type == 'X' and ui_props.active_index != -3:
            sr = bpy.context.scene['search results']
            asset_data = sr[ui_props.active_index]
            print(asset_data['name'])
            print('delete')
            paths.delete_asset_debug(asset_data)
            asset_data['downloaded'] = 0
            return {'RUNNING_MODAL'}
        return {'PASS_THROUGH'}

    def invoke(self, context, event):
        # FIRST START SEARCH
        ui_props = context.scene.blenderkitUI

        if self.do_search:
            # we erase search keywords for cateogry search now, since these combinations usually return nothing now.
            # when the db gets bigger, this can be deleted.
            if self.category != '':
                sprops = utils.get_search_props()
                sprops.search_keywords = ''
            search.search(category=self.category)

        if ui_props.assetbar_on:
            # we don't want to run the assetbar many times, that's why it has a switch on/off behaviour,
            # unless being called with 'keep_running' prop.
            if not self.keep_running:
                # this sends message to the originally running operator, so it quits, and then it ends this one too.
                # If it initiated a search, the search will finish in a thread. The switch off procedure is run
                # by the 'original' operator, since if we get here, it means
                # same operator is allready running.
                ui_props.turn_off = True
                # if there was an error, we need to turn off these props so we can restart after 2 clicks
                ui_props.assetbar_on = False

            else:
                pass
            return {'FINISHED'}

        ui_props.dragging = False  # only for cases where assetbar ended with an error.
        ui_props.assetbar_on = True
        ui_props.turn_off = False

        sr = bpy.context.scene.get('search results')
        if sr is None:
            bpy.context.scene['search results'] = []

        if context.area.type == 'VIEW_3D':
            # the arguments we pass the the callback
            args = (self, context)
            self.area = context.area
            self.scene = bpy.context.scene

            for r in self.area.regions:
                if r.type == 'WINDOW':
                    self.region = r

            update_ui_size(self.area, self.region)

            self._handle_2d = bpy.types.SpaceView3D.draw_handler_add(draw_callback_2d, args, 'WINDOW', 'POST_PIXEL')
            self._handle_3d = bpy.types.SpaceView3D.draw_handler_add(draw_callback_3d, args, 'WINDOW', 'POST_VIEW')

            context.window_manager.modal_handler_add(self)
            ui_props.assetbar_on = True
            return {'RUNNING_MODAL'}
        else:

            self.report({'WARNING'}, "View3D not found, cannot run operator")
            return {'CANCELLED'}

    def execute(self, context):
        return {'RUNNING_MODAL'}


classess = (
    AssetBarOperator,

)

# store keymaps here to access after registration
addon_keymaps = []


def register_ui():
    global handler_2d, handler_3d

    for c in classess:
        bpy.utils.register_class(c)

    args = (None, bpy.context)

    handler_2d = bpy.types.SpaceView3D.draw_handler_add(draw_callback_2d_progress, args, 'WINDOW', 'POST_PIXEL')
    handler_3d = bpy.types.SpaceView3D.draw_handler_add(draw_callback_3d_progress, args, 'WINDOW', 'POST_VIEW')

    wm = bpy.context.window_manager

    # spaces solved by registering shortcut to Window. Couldn't register object mode before somehow.
    if not wm.keyconfigs.addon:
        return
    km = wm.keyconfigs.addon.keymaps.new(name="Window", space_type='EMPTY')
    kmi = km.keymap_items.new(AssetBarOperator.bl_idname, 'SEMI_COLON', 'PRESS', ctrl=False, shift=False)
    kmi.properties.keep_running = False
    kmi.properties.do_search = False

    addon_keymaps.append(km)


def unregister_ui():
    global handler_2d, handler_3d

    bpy.types.SpaceView3D.draw_handler_remove(handler_2d, 'WINDOW')
    bpy.types.SpaceView3D.draw_handler_remove(handler_3d, 'WINDOW')

    for c in classess:
        bpy.utils.unregister_class(c)

    args = (None, bpy.context)

    wm = bpy.context.window_manager
    if not wm.keyconfigs.addon:
        return

    for km in addon_keymaps:
        wm.keyconfigs.addon.keymaps.remove(km)
    del addon_keymaps[:]