gui_demo.py

# based on https://github.com/isl-org/Open3D/blob/master/examples/python/visualization/vis_gui.py
import glob
import numpy as np
import open3d as o3d
import open3d.visualization.gui as gui
import open3d.visualization.rendering as rendering
import os
import platform
import sys
import json
import time
import torch
from mcubes import marching_cubes
from model import get_model
from utils.data_utils import get_biggest_connected_compoent

isMacOS = (platform.system() == "Darwin")

if torch.cuda.is_available():
    GPU_ID = 0
    print("Using GPU 0")
else:
    GPU_ID = -1
    print("Using CPU")


class Settings:
    UNLIT = "defaultUnlit"
    LIT = "defaultLit"
    NORMALS = "normals"
    DEPTH = "depth"

    DEFAULT_PROFILE_NAME = "Bright day with sun at +Y [default]"
    POINT_CLOUD_PROFILE_NAME = "Cloudy day (no direct sun)"
    CUSTOM_PROFILE_NAME = "Custom"
    LIGHTING_PROFILES = {
        DEFAULT_PROFILE_NAME: {
            "ibl_intensity": 45000,
            "sun_intensity": 45000,
            "sun_dir": [0.577, -0.577, -0.577],
            # "ibl_rotation":
            "use_ibl": True,
            "use_sun": True,
        },
        "Bright day with sun at -Y": {
            "ibl_intensity": 45000,
            "sun_intensity": 45000,
            "sun_dir": [0.577, 0.577, 0.577],
            # "ibl_rotation":
            "use_ibl": True,
            "use_sun": True,
        },
        "Bright day with sun at +Z": {
            "ibl_intensity": 45000,
            "sun_intensity": 45000,
            "sun_dir": [0.577, 0.577, -0.577],
            # "ibl_rotation":
            "use_ibl": True,
            "use_sun": True,
        },
        "Less Bright day with sun at +Y": {
            "ibl_intensity": 35000,
            "sun_intensity": 50000,
            "sun_dir": [0.577, -0.577, -0.577],
            # "ibl_rotation":
            "use_ibl": True,
            "use_sun": True,
        },
        "Less Bright day with sun at -Y": {
            "ibl_intensity": 35000,
            "sun_intensity": 50000,
            "sun_dir": [0.577, 0.577, 0.577],
            # "ibl_rotation":
            "use_ibl": True,
            "use_sun": True,
        },
        "Less Bright day with sun at +Z": {
            "ibl_intensity": 35000,
            "sun_intensity": 50000,
            "sun_dir": [0.577, 0.577, -0.577],
            # "ibl_rotation":
            "use_ibl": True,
            "use_sun": True,
        },
        POINT_CLOUD_PROFILE_NAME: {
            "ibl_intensity": 60000,
            "sun_intensity": 50000,
            "use_ibl": True,
            "use_sun": False,
            # "ibl_rotation":
        },
    }

    DEFAULT_MATERIAL_NAME = "Polished ceramic [default]"
    PREFAB = {
        DEFAULT_MATERIAL_NAME: {
            "metallic": 0.0,
            "roughness": 0.7,
            "reflectance": 0.5,
            "clearcoat": 0.2,
            "clearcoat_roughness": 0.2,
            "anisotropy": 0.0
        },
        "Metal (rougher)": {
            "metallic": 1.0,
            "roughness": 0.5,
            "reflectance": 0.9,
            "clearcoat": 0.0,
            "clearcoat_roughness": 0.0,
            "anisotropy": 0.0
        },
        "Metal (smoother)": {
            "metallic": 1.0,
            "roughness": 0.3,
            "reflectance": 0.9,
            "clearcoat": 0.0,
            "clearcoat_roughness": 0.0,
            "anisotropy": 0.0
        },
        "Plastic": {
            "metallic": 0.0,
            "roughness": 0.5,
            "reflectance": 0.5,
            "clearcoat": 0.5,
            "clearcoat_roughness": 0.2,
            "anisotropy": 0.0
        },
        "Glazed ceramic": {
            "metallic": 0.0,
            "roughness": 0.5,
            "reflectance": 0.9,
            "clearcoat": 1.0,
            "clearcoat_roughness": 0.1,
            "anisotropy": 0.0
        },
        "Clay": {
            "metallic": 0.0,
            "roughness": 1.0,
            "reflectance": 0.5,
            "clearcoat": 0.1,
            "clearcoat_roughness": 0.287,
            "anisotropy": 0.0
        },
    }

    def __init__(self):
        self.mouse_model = gui.SceneWidget.Controls.ROTATE_CAMERA
        self.bg_color = gui.Color(1, 1, 1)
        self.show_skybox = False
        self.show_axes = False
        self.use_ibl = True
        self.use_sun = True
        self.new_ibl_name = None  # clear to None after loading
        self.ibl_intensity = 30000
        self.sun_intensity = 30000
        self.sun_dir = [0.577, -0.577, -0.577]
        self.sun_color = gui.Color(1, 1, 1)

        self.apply_material = True  # clear to False after processing
        self._materials = {
            Settings.LIT: rendering.MaterialRecord(),
            Settings.UNLIT: rendering.MaterialRecord(),
            Settings.NORMALS: rendering.MaterialRecord(),
            Settings.DEPTH: rendering.MaterialRecord()
        }
        self._materials[Settings.LIT].base_color = [0.9, 0.9, 0.9, 1.0]
        self._materials[Settings.LIT].shader = Settings.LIT
        self._materials[Settings.UNLIT].base_color = [0.9, 0.9, 0.9, 1.0]
        self._materials[Settings.UNLIT].shader = Settings.UNLIT
        self._materials[Settings.NORMALS].shader = Settings.NORMALS
        self._materials[Settings.DEPTH].shader = Settings.DEPTH

        # Conveniently, assigning from self._materials[...] assigns a reference,
        # not a copy, so if we change the property of a material, then switch
        # to another one, then come back, the old setting will still be there.
        self.material = self._materials[Settings.LIT]

    def set_material(self, name):
        self.material = self._materials[name]
        self.apply_material = True

    def apply_material_prefab(self, name):
        assert (self.material.shader == Settings.LIT)
        prefab = Settings.PREFAB[name]
        for key, val in prefab.items():
            setattr(self.material, "base_" + key, val)

    def apply_lighting_profile(self, name):
        profile = Settings.LIGHTING_PROFILES[name]
        for key, val in profile.items():
            setattr(self, key, val)


def _load_ssg_model(ckpt_dir):
    """load pretrained ssg model"""
    if not os.path.exists(ckpt_dir):
        print(f"Checkpoint folder '{ckpt_dir}' not exists.")
        return None

    # a simplified config object
    class TinyConfig:
        def __init__(self, config_path) -> None:
            with open(config_path, "r") as fp:
                save_args = json.load(fp)
            for k, v in save_args.items():
                self.__setattr__(k, v)
            self.exp_dir = ckpt_dir # keep the path absolute path
            self.log_dir = os.path.join(ckpt_dir, 'log')
            self.model_dir = os.path.join(ckpt_dir, 'model')
            self.ckpt = None
            self.gpu_ids = GPU_ID
    
    config_path = os.path.join(ckpt_dir, "config.json")
    cfg = TinyConfig(config_path)
    ssg_model = get_model(cfg)
    
    # load from checkpoint
    n_scales = cfg.ckpt
    if cfg.ckpt is None: # otherwise load highest scale model by default
        filename = sorted(os.listdir(cfg.model_dir))[-1]
        n_scales = int(filename.split('_')[0][-1])
    ssg_model.load_ckpt(n_scales)
    print("model loaded")
    return ssg_model


class AppWindow:
    DEFAULT_IBL = "default"

    MATERIAL_NAMES = ["Lit", "Unlit", "Normals", "Depth"]
    MATERIAL_SHADERS = [
        Settings.LIT, Settings.UNLIT, Settings.NORMALS, Settings.DEPTH
    ]

    def __init__(self, width, height):
        # ssg model related attributes
        self.ssg_model = None
        self.mesh = None

        self.settings = Settings()
        resource_path = gui.Application.instance.resource_path
        self.settings.new_ibl_name = resource_path + "/" + AppWindow.DEFAULT_IBL

        self.window = gui.Application.instance.create_window(
            "SingleShapeGen", width, height)
        w = self.window  # to make the code more concise

        # 3D widget
        self._scene = gui.SceneWidget()
        self._scene.scene = rendering.Open3DScene(w.renderer)
        self._scene.set_on_sun_direction_changed(self._on_sun_dir)

        # ---- Settings panel ----
        # Rather than specifying sizes in pixels, which may vary in size based
        # on the monitor, especially on macOS which has 220 dpi monitors, use
        # the em-size. This way sizings will be proportional to the font size,
        # which will create a more visually consistent size across platforms.
        em = w.theme.font_size
        separation_height = int(round(0.5 * em))
        self.em = em
        self.separation_height = separation_height

        # Widgets are laid out in layouts: gui.Horiz, gui.Vert,
        # gui.CollapsableVert, and gui.VGrid. By nesting the layouts we can
        # achieve complex designs. Usually we use a vertical layout as the
        # topmost widget, since widgets tend to be organized from top to bottom.
        # Within that, we usually have a series of horizontal layouts for each
        # row. All layouts take a spacing parameter, which is the spacing
        # between items in the widget, and a margins parameter, which specifies
        # the spacing of the left, top, right, bottom margins. (This acts like
        # the 'padding' property in CSS.)
        self._settings_panel = gui.Vert(
            0, gui.Margins(0.25 * em, 0.25 * em, 0.25 * em, 0.25 * em))

        model_ctrls = self._ssgmodel_controls_interface(em, separation_height)
        self._settings_panel.add_fixed(separation_height)
        self._settings_panel.add_child(model_ctrls)

        view_ctrls = self._view_controls_interface(em, separation_height)
        self._settings_panel.add_fixed(separation_height)
        self._settings_panel.add_child(view_ctrls)

        light_ctrls = self._lighting_controls_interface(em, separation_height)
        self._settings_panel.add_fixed(separation_height)
        self._settings_panel.add_child(light_ctrls)

        material_settings = self._material_settings_interface(em, separation_height)
        self._settings_panel.add_fixed(separation_height)
        self._settings_panel.add_child(material_settings)
        # ----

        # Normally our user interface can be children of all one layout (usually
        # a vertical layout), which is then the only child of the window. In our
        # case we want the scene to take up all the space and the settings panel
        # to go above it. We can do this custom layout by providing an on_layout
        # callback. The on_layout callback should set the frame
        # (position + size) of every child correctly. After the callback is
        # done the window will layout the grandchildren.
        w.set_on_layout(self._on_layout)
        w.add_child(self._scene)
        w.add_child(self._settings_panel)

        self._apply_settings()

    def _ssgmodel_controls_interface(self, em, separation_height):
        model_ctrls = gui.CollapsableVert("SSG model", 0.25 * em,
                                         gui.Margins(em, 0, 0, 0))
        # checkpoint loading
        self._load_button = gui.Button("Load checkpoint folder")
        self._load_button.horizontal_padding_em = 0.5
        self._load_button.vertical_padding_em = 0
        self._load_button.set_on_clicked(self._on_load_button)
        model_ctrls.add_child(self._load_button)

        self.ckpt_textbox = gui.TextEdit()
        load_button_layout = gui.Horiz()
        load_button_layout.add_child(self.ckpt_textbox)

        model_ctrls.add_child(load_button_layout)

        # generation
        model_ctrls.add_fixed(separation_height)
        model_ctrls.add_child(gui.Label("Generation"))
        
        # resize slider
        self._resize_x_slider = gui.Slider(gui.Slider.DOUBLE)
        self._resize_x_slider.set_limits(0.5, 2.0)
        self._resize_x_slider.double_value = 1.0
        h = gui.Horiz(0.5 * em)
        h.add_child(gui.Label("Resize x"))
        h.add_child(self._resize_x_slider)
        model_ctrls.add_child(h)
        
        self._resize_y_slider = gui.Slider(gui.Slider.DOUBLE)
        self._resize_y_slider.set_limits(0.5, 2.0)
        self._resize_y_slider.double_value = 1.0
        h = gui.Horiz(0.5 * em)
        h.add_child(gui.Label("Resize y"))
        h.add_child(self._resize_y_slider)
        model_ctrls.add_child(h)
        
        self._resize_z_slider = gui.Slider(gui.Slider.DOUBLE)
        self._resize_z_slider.set_limits(0.5, 2.0)
        self._resize_z_slider.double_value = 1.0
        h = gui.Horiz(0.5 * em)
        h.add_child(gui.Label("Resize z"))
        h.add_child(self._resize_z_slider)
        model_ctrls.add_child(h)

        # cleanup check box
        self._cleanup_box = gui.Checkbox("Clean up")
        self._cleanup_box.set_on_checked(self._on_cleanup_box)
        self._cleanup_box.checked = True
        model_ctrls.add_child(self._cleanup_box)

        # laplacian smooth slider
        self._laplacian_slider = gui.Slider(gui.Slider.INT)
        self._laplacian_slider.set_limits(0, 5)
        self._laplacian_slider.int_value = 3
        self._laplacian_slider.set_on_value_changed(self._on_laplacian_slider)
        h = gui.Horiz(0.5 * em)
        h.add_child(gui.Label("Laplacian smooth"))
        h.add_child(self._laplacian_slider)
        model_ctrls.add_child(h)

        # generate button
        self._generate_button = gui.Button("Generate")
        self._generate_button.horizontal_padding_em = 0.5
        self._generate_button.vertical_padding_em = 0
        self._generate_button.set_on_clicked(self._on_generate_button)
        
        # export button
        self._export_button = gui.Button("Export")
        self._export_button.horizontal_padding_em = 0.5
        self._export_button.vertical_padding_em = 0
        self._export_button.set_on_clicked(self._on_export_button)
        
        h = gui.Horiz(0.5 * em)  # row 0
        h.add_child(self._generate_button)
        h.add_child(self._export_button)
        model_ctrls.add_child(h)
        return model_ctrls

    def _view_controls_interface(self, em, separation_height):
        
        # Create a collapsible vertical widget, which takes up enough vertical
        # space for all its children when open, but only enough for text when
        # closed. This is useful for property pages, so the user can hide sets
        # of properties they rarely use.
        view_ctrls = gui.CollapsableVert("View controls", 0.25 * em,
                                         gui.Margins(em, 0, 0, 0))
        view_ctrls.set_is_open(False)

        self._arcball_button = gui.Button("Arcball")
        self._arcball_button.horizontal_padding_em = 0.5
        self._arcball_button.vertical_padding_em = 0
        self._arcball_button.set_on_clicked(self._set_mouse_mode_rotate)
        self._fly_button = gui.Button("Fly")
        self._fly_button.horizontal_padding_em = 0.5
        self._fly_button.vertical_padding_em = 0
        self._fly_button.set_on_clicked(self._set_mouse_mode_fly)
        self._model_button = gui.Button("Model")
        self._model_button.horizontal_padding_em = 0.5
        self._model_button.vertical_padding_em = 0
        self._model_button.set_on_clicked(self._set_mouse_mode_model)
        self._sun_button = gui.Button("Sun")
        self._sun_button.horizontal_padding_em = 0.5
        self._sun_button.vertical_padding_em = 0
        self._sun_button.set_on_clicked(self._set_mouse_mode_sun)
        self._ibl_button = gui.Button("Environment")
        self._ibl_button.horizontal_padding_em = 0.5
        self._ibl_button.vertical_padding_em = 0
        self._ibl_button.set_on_clicked(self._set_mouse_mode_ibl)
        view_ctrls.add_child(gui.Label("Mouse controls"))
        # We want two rows of buttons, so make two horizontal layouts. We also
        # want the buttons centered, which we can do be putting a stretch item
        # as the first and last item. Stretch items take up as much space as
        # possible, and since there are two, they will each take half the extra
        # space, thus centering the buttons.
        h = gui.Horiz(0.25 * em)  # row 1
        h.add_stretch()
        h.add_child(self._arcball_button)
        h.add_child(self._fly_button)
        h.add_child(self._model_button)
        h.add_stretch()
        view_ctrls.add_child(h)
        h = gui.Horiz(0.25 * em)  # row 2
        h.add_stretch()
        h.add_child(self._sun_button)
        h.add_child(self._ibl_button)
        h.add_stretch()
        view_ctrls.add_child(h)

        self._show_skybox = gui.Checkbox("Show skymap")
        self._show_skybox.set_on_checked(self._on_show_skybox)
        view_ctrls.add_fixed(separation_height)
        view_ctrls.add_child(self._show_skybox)

        self._bg_color = gui.ColorEdit()
        self._bg_color.set_on_value_changed(self._on_bg_color)

        grid = gui.VGrid(2, 0.25 * em)
        grid.add_child(gui.Label("BG Color"))
        grid.add_child(self._bg_color)
        view_ctrls.add_child(grid)

        self._show_axes = gui.Checkbox("Show axes")
        self._show_axes.set_on_checked(self._on_show_axes)
        view_ctrls.add_fixed(separation_height)
        view_ctrls.add_child(self._show_axes)

        self._profiles = gui.Combobox()
        for name in sorted(Settings.LIGHTING_PROFILES.keys()):
            self._profiles.add_item(name)
        self._profiles.add_item(Settings.CUSTOM_PROFILE_NAME)
        self._profiles.set_on_selection_changed(self._on_lighting_profile)
        view_ctrls.add_fixed(separation_height)
        view_ctrls.add_child(gui.Label("Lighting profiles"))
        view_ctrls.add_child(self._profiles)
        
        return view_ctrls

    def _lighting_controls_interface(self, em, separation_height):
        advanced = gui.CollapsableVert("Advanced lighting", 0,
                                       gui.Margins(em, 0, 0, 0))
        advanced.set_is_open(False)

        self._use_ibl = gui.Checkbox("HDR map")
        self._use_ibl.set_on_checked(self._on_use_ibl)
        self._use_sun = gui.Checkbox("Sun")
        self._use_sun.set_on_checked(self._on_use_sun)
        advanced.add_child(gui.Label("Light sources"))
        h = gui.Horiz(em)
        h.add_child(self._use_ibl)
        h.add_child(self._use_sun)
        advanced.add_child(h)

        self._ibl_map = gui.Combobox()
        for ibl in glob.glob(gui.Application.instance.resource_path +
                             "/*_ibl.ktx"):

            self._ibl_map.add_item(os.path.basename(ibl[:-8]))
        self._ibl_map.selected_text = AppWindow.DEFAULT_IBL
        self._ibl_map.set_on_selection_changed(self._on_new_ibl)
        self._ibl_intensity = gui.Slider(gui.Slider.INT)
        self._ibl_intensity.set_limits(0, 200000)
        self._ibl_intensity.set_on_value_changed(self._on_ibl_intensity)
        grid = gui.VGrid(2, 0.25 * em)
        grid.add_child(gui.Label("HDR map"))
        grid.add_child(self._ibl_map)
        grid.add_child(gui.Label("Intensity"))
        grid.add_child(self._ibl_intensity)
        advanced.add_fixed(separation_height)
        advanced.add_child(gui.Label("Environment"))
        advanced.add_child(grid)

        self._sun_intensity = gui.Slider(gui.Slider.INT)
        self._sun_intensity.set_limits(0, 200000)
        self._sun_intensity.set_on_value_changed(self._on_sun_intensity)
        self._sun_dir = gui.VectorEdit()
        self._sun_dir.set_on_value_changed(self._on_sun_dir)
        self._sun_color = gui.ColorEdit()
        self._sun_color.set_on_value_changed(self._on_sun_color)
        grid = gui.VGrid(2, 0.25 * em)
        grid.add_child(gui.Label("Intensity"))
        grid.add_child(self._sun_intensity)
        grid.add_child(gui.Label("Direction"))
        grid.add_child(self._sun_dir)
        grid.add_child(gui.Label("Color"))
        grid.add_child(self._sun_color)
        advanced.add_fixed(separation_height)
        advanced.add_child(gui.Label("Sun (Directional light)"))
        advanced.add_child(grid)

        return advanced

    def _material_settings_interface(self, em, separation_height):
        material_settings = gui.CollapsableVert("Material settings", 0,
                                                gui.Margins(em, 0, 0, 0))
        material_settings.set_is_open(False)

        self._shader = gui.Combobox()
        self._shader.add_item(AppWindow.MATERIAL_NAMES[0])
        self._shader.add_item(AppWindow.MATERIAL_NAMES[1])
        self._shader.add_item(AppWindow.MATERIAL_NAMES[2])
        self._shader.add_item(AppWindow.MATERIAL_NAMES[3])
        self._shader.set_on_selection_changed(self._on_shader)
        self._material_prefab = gui.Combobox()
        for prefab_name in sorted(Settings.PREFAB.keys()):
            self._material_prefab.add_item(prefab_name)
        self._material_prefab.selected_text = Settings.DEFAULT_MATERIAL_NAME
        self._material_prefab.set_on_selection_changed(self._on_material_prefab)
        self._material_color = gui.ColorEdit()
        self._material_color.set_on_value_changed(self._on_material_color)
        self._point_size = gui.Slider(gui.Slider.INT)
        self._point_size.set_limits(1, 10)
        self._point_size.set_on_value_changed(self._on_point_size)

        grid = gui.VGrid(2, 0.25 * em)
        grid.add_child(gui.Label("Type"))
        grid.add_child(self._shader)
        grid.add_child(gui.Label("Material"))
        grid.add_child(self._material_prefab)
        grid.add_child(gui.Label("Color"))
        grid.add_child(self._material_color)
        grid.add_child(gui.Label("Point size"))
        grid.add_child(self._point_size)
        material_settings.add_child(grid)

        return material_settings

    def _apply_settings(self):
        bg_color = [
            self.settings.bg_color.red, self.settings.bg_color.green,
            self.settings.bg_color.blue, self.settings.bg_color.alpha
        ]
        self._scene.scene.set_background(bg_color)
        self._scene.scene.show_skybox(self.settings.show_skybox)
        self._scene.scene.show_axes(self.settings.show_axes)
        if self.settings.new_ibl_name is not None:
            self._scene.scene.scene.set_indirect_light(
                self.settings.new_ibl_name)
            # Clear new_ibl_name, so we don't keep reloading this image every
            # time the settings are applied.
            self.settings.new_ibl_name = None
        self._scene.scene.scene.enable_indirect_light(self.settings.use_ibl)
        self._scene.scene.scene.set_indirect_light_intensity(
            self.settings.ibl_intensity)
        sun_color = [
            self.settings.sun_color.red, self.settings.sun_color.green,
            self.settings.sun_color.blue
        ]
        self._scene.scene.scene.set_sun_light(self.settings.sun_dir, sun_color,
                                              self.settings.sun_intensity)
        self._scene.scene.scene.enable_sun_light(self.settings.use_sun)

        if self.settings.apply_material:
            self._scene.scene.update_material(self.settings.material)
            self.settings.apply_material = False

        self._bg_color.color_value = self.settings.bg_color
        self._show_skybox.checked = self.settings.show_skybox
        self._show_axes.checked = self.settings.show_axes
        self._use_ibl.checked = self.settings.use_ibl
        self._use_sun.checked = self.settings.use_sun
        self._ibl_intensity.int_value = self.settings.ibl_intensity
        self._sun_intensity.int_value = self.settings.sun_intensity
        self._sun_dir.vector_value = self.settings.sun_dir
        self._sun_color.color_value = self.settings.sun_color
        self._material_prefab.enabled = (
            self.settings.material.shader == Settings.LIT)
        c = gui.Color(self.settings.material.base_color[0],
                      self.settings.material.base_color[1],
                      self.settings.material.base_color[2],
                      self.settings.material.base_color[3])
        self._material_color.color_value = c
        self._point_size.double_value = self.settings.material.point_size

    def _on_layout(self, layout_context):
        # The on_layout callback should set the frame (position + size) of every
        # child correctly. After the callback is done the window will layout
        # the grandchildren.
        r = self.window.content_rect
        self._scene.frame = r
        width = 17 * layout_context.theme.font_size
        height = min(
            r.height,
            self._settings_panel.calc_preferred_size(
                layout_context, gui.Widget.Constraints()).height)
        self._settings_panel.frame = gui.Rect(r.get_right() - width, r.y, width,
                                              height)

    def _on_load_button(self):
        dlg = gui.FileDialog(gui.FileDialog.OPEN_DIR, "Choose file to load",
                             self.window.theme)

        # A file dialog MUST define on_cancel and on_done functions
        dlg.set_on_cancel(self._on_file_dialog_cancel)
        dlg.set_on_done(self._on_load_dialog_done)
        self.window.show_dialog(dlg)

    def _on_file_dialog_cancel(self):
        self.window.close_dialog()

    def _on_load_dialog_done(self, filename):
        self.window.close_dialog()
        self.load_model(filename)

    def load_model(self, ckpt_dir=None):
        if ckpt_dir is None:
            ckpt_dir = self.ckpt_textbox.text_value
        if not os.path.exists(ckpt_dir):
            self.window.show_message_box("Error", f"Path '{ckpt_dir}' not exists.")
            print(f"Path '{ckpt_dir}' not exists.")
            return
        
        try:
            self.ssg_model = _load_ssg_model(ckpt_dir)
            if ckpt_dir is not None:
                self.ckpt_textbox.text_value = ckpt_dir
            self.mesh = None
            self._scene.scene.clear_geometry()
        except Exception as e:
            self.window.show_message_box("Error", "Load checkpoint failed.")
            print(e)

    def _on_cleanup_box(self, check):
        print("clean up:", check)
        # TODO: update current geometry

    def _on_laplacian_slider(self, iterations):
        print("Laplacian smooth iterations:", iterations)
        # TODO: update current geometry

    def _on_generate_button(self):
        if self.ssg_model is None:
            return

        print("########## Generating next ##########")

        since = time.time()
        with torch.no_grad():
            resize = (round(self._resize_x_slider.double_value, 2),
                      round(self._resize_y_slider.double_value, 2),
                      round(self._resize_z_slider.double_value, 2))
            voxels = self.ssg_model.generate('rand', resize_factor=resize)
        end = time.time()
        print("ssg model generate time:", end - since)

        since = time.time()
        voxels = voxels.detach().cpu().numpy()[0, 0]
        voxels = voxels > 0.5
        end = time.time()
        print("gpu->cpu time:", end - since)


        since = time.time()
        if self._cleanup_box.checked:
            voxels = get_biggest_connected_compoent(voxels)
        end = time.time()
        print("cleanup time:", end - since)

        since = time.time()
        voxels = np.pad(voxels, 1)
        vertices, faces = marching_cubes(voxels, 0.5)
        end = time.time()
        print("marching cubes time:", end - since)

        # normalize
        min_corner = np.min(vertices, axis=0)
        max_corner = np.max(vertices, axis=0)
        box_size = np.abs(max_corner - min_corner)
        vertices = vertices - min_corner[np.newaxis]
        vertices = vertices * (1. / np.max(box_size))

        since = time.time()
        vertices = o3d.utility.Vector3dVector(vertices)
        faces = o3d.utility.Vector3iVector(faces)
        mesh = o3d.geometry.TriangleMesh(vertices, faces)
        if self._laplacian_slider.int_value > 0:
            mesh = mesh.filter_smooth_laplacian(self._laplacian_slider.int_value)
        mesh.compute_vertex_normals()
        mesh.paint_uniform_color([0.5, 0.5, 0.5])
        self.mesh = mesh # for later export
        material = rendering.MaterialRecord()
        material.shader = 'defaultLit'
        end = time.time()
        print("open3d mesh+material init time:", end - since)

        since = time.time()
        self._scene.scene.clear_geometry()
        self._scene.scene.add_geometry("__model__", mesh, material)
        bounds = self._scene.scene.bounding_box
        self._scene.setup_camera(60, bounds, bounds.get_center())
        end = time.time()
        print("scene update time:", end - since)

    def _on_export_button(self):
        if self.mesh is None:
            return

        dlg = gui.FileDialog(gui.FileDialog.SAVE, "Choose file to save",
                             self.window.theme)
        dlg.set_on_cancel(self._on_file_dialog_cancel)
        dlg.set_on_done(self._on_export_dialog_done)
        self.window.show_dialog(dlg)

    def _on_export_dialog_done(self, filename):
        self.window.close_dialog()
        try:
            o3d.io.write_triangle_mesh(filename, self.mesh, write_vertex_colors=False)
            print(f"Save mesh to '{filename}'")
        except Exception as e:
            print("Save mesh failed.", e)

    def _set_mouse_mode_rotate(self):
        self._scene.set_view_controls(gui.SceneWidget.Controls.ROTATE_CAMERA)

    def _set_mouse_mode_fly(self):
        self._scene.set_view_controls(gui.SceneWidget.Controls.FLY)

    def _set_mouse_mode_sun(self):
        self._scene.set_view_controls(gui.SceneWidget.Controls.ROTATE_SUN)

    def _set_mouse_mode_ibl(self):
        self._scene.set_view_controls(gui.SceneWidget.Controls.ROTATE_IBL)

    def _set_mouse_mode_model(self):
        self._scene.set_view_controls(gui.SceneWidget.Controls.ROTATE_MODEL)

    def _on_bg_color(self, new_color):
        self.settings.bg_color = new_color
        self._apply_settings()

    def _on_show_skybox(self, show):
        self.settings.show_skybox = show
        self._apply_settings()

    def _on_show_axes(self, show):
        self.settings.show_axes = show
        self._apply_settings()

    def _on_use_ibl(self, use):
        self.settings.use_ibl = use
        self._profiles.selected_text = Settings.CUSTOM_PROFILE_NAME
        self._apply_settings()

    def _on_use_sun(self, use):
        self.settings.use_sun = use
        self._profiles.selected_text = Settings.CUSTOM_PROFILE_NAME
        self._apply_settings()

    def _on_lighting_profile(self, name, index):
        if name != Settings.CUSTOM_PROFILE_NAME:
            self.settings.apply_lighting_profile(name)
            self._apply_settings()

    def _on_new_ibl(self, name, index):
        self.settings.new_ibl_name = gui.Application.instance.resource_path + "/" + name
        self._profiles.selected_text = Settings.CUSTOM_PROFILE_NAME
        self._apply_settings()

    def _on_ibl_intensity(self, intensity):
        self.settings.ibl_intensity = int(intensity)
        self._profiles.selected_text = Settings.CUSTOM_PROFILE_NAME
        self._apply_settings()

    def _on_sun_intensity(self, intensity):
        self.settings.sun_intensity = int(intensity)
        self._profiles.selected_text = Settings.CUSTOM_PROFILE_NAME
        self._apply_settings()

    def _on_sun_dir(self, sun_dir):
        self.settings.sun_dir = sun_dir
        self._profiles.selected_text = Settings.CUSTOM_PROFILE_NAME
        self._apply_settings()

    def _on_sun_color(self, color):
        self.settings.sun_color = color
        self._apply_settings()

    def _on_shader(self, name, index):
        self.settings.set_material(AppWindow.MATERIAL_SHADERS[index])
        self._apply_settings()

    def _on_material_prefab(self, name, index):
        self.settings.apply_material_prefab(name)
        self.settings.apply_material = True
        self._apply_settings()

    def _on_material_color(self, color):
        self.settings.material.base_color = [
            color.red, color.green, color.blue, color.alpha
        ]
        self.settings.apply_material = True
        self._apply_settings()

    def _on_point_size(self, size):
        self.settings.material.point_size = int(size)
        self.settings.apply_material = True
        self._apply_settings()


def main():
    # We need to initialize the application, which finds the necessary shaders
    # for rendering and prepares the cross-platform window abstraction.
    gui.Application.instance.initialize()

    w = AppWindow(1024, 768)

    if len(sys.argv) > 1:
        path = sys.argv[1]
        w.load_model(path)

    # Run the event loop. This will not return until the last window is closed.
    gui.Application.instance.run()


if __name__ == "__main__":
    main()