gui.py

import os
import tyro
import numpy as np
import torch
import torch.nn as nn
import torch.nn.functional as F

from core.options import AllConfigs, Options
from core.gs import GaussianRenderer

import dearpygui.dearpygui as dpg

import kiui
from kiui.cam import OrbitCamera


class GUI:
    def __init__(self, opt: Options):
        self.opt = opt
        self.W = opt.output_size
        self.H = opt.output_size
        self.cam = OrbitCamera(self.W, self.H, r=opt.cam_radius, fovy=opt.fovy)

        self.device = torch.device("cuda")

        self.tan_half_fov = np.tan(0.5 * np.deg2rad(opt.fovy))
        self.proj_matrix = torch.zeros(4, 4, dtype=torch.float32, device=self.device)
        self.proj_matrix[0, 0] = 1 / self.tan_half_fov
        self.proj_matrix[1, 1] = 1 / self.tan_half_fov
        self.proj_matrix[2, 2] = (opt.zfar + opt.znear) / (opt.zfar - opt.znear)
        self.proj_matrix[3, 2] = - (opt.zfar * opt.znear) / (opt.zfar - opt.znear)
        self.proj_matrix[2, 3] = 1

        self.mode = "image"
        
        self.buffer_image = np.ones((self.W, self.H, 3), dtype=np.float32)
        self.need_update = True  # update buffer_image

        # renderer
        self.renderer = GaussianRenderer(opt)
        self.gaussain_scale_factor = 1

        self.gaussians = self.renderer.load_ply(opt.test_path).to(self.device)

        dpg.create_context()
        self.register_dpg()
        self.test_step()

    def __del__(self):
        dpg.destroy_context()

    @torch.no_grad()
    def test_step(self):
        # ignore if no need to update
        if not self.need_update:
            return

        starter = torch.cuda.Event(enable_timing=True)
        ender = torch.cuda.Event(enable_timing=True)
        starter.record()

        # should update image
        if self.need_update:
            # render image

            cam_poses = torch.from_numpy(self.cam.pose).unsqueeze(0).to(self.device)
            cam_poses[:, :3, 1:3] *= -1 # invert up & forward direction
            
            # cameras needed by gaussian rasterizer
            cam_view = torch.inverse(cam_poses).transpose(1, 2) # [V, 4, 4]
            cam_view_proj = cam_view @ self.proj_matrix # [V, 4, 4]
            cam_pos = - cam_poses[:, :3, 3] # [V, 3]
            
            buffer_image = self.renderer.render(self.gaussians.unsqueeze(0), cam_view.unsqueeze(0), cam_view_proj.unsqueeze(0), cam_pos.unsqueeze(0), scale_modifier=self.gaussain_scale_factor)[self.mode]
            buffer_image = buffer_image.squeeze(1) # [B, C, H, W]

            if self.mode in ['alpha']:
                buffer_image = buffer_image.repeat(1, 3, 1, 1)
                
            buffer_image = F.interpolate(
                buffer_image,
                size=(self.H, self.W),
                mode="bilinear",
                align_corners=False,
            ).squeeze(0)

            self.buffer_image = (
                buffer_image.permute(1, 2, 0)
                .contiguous()
                .clamp(0, 1)
                .contiguous()
                .detach()
                .cpu()
                .numpy()
            )

            self.need_update = False

        ender.record()
        torch.cuda.synchronize()
        t = starter.elapsed_time(ender)
    
        dpg.set_value("_log_infer_time", f"{t:.4f}ms ({int(1000/t)} FPS)")
        dpg.set_value(
            "_texture", self.buffer_image
        )  # buffer must be contiguous, else seg fault!

    def register_dpg(self):
        ### register texture

        with dpg.texture_registry(show=False):
            dpg.add_raw_texture(
                self.W,
                self.H,
                self.buffer_image,
                format=dpg.mvFormat_Float_rgb,
                tag="_texture",
            )

        ### register window

        # the rendered image, as the primary window
        with dpg.window(
            tag="_primary_window",
            width=self.W,
            height=self.H,
            pos=[0, 0],
            no_move=True,
            no_title_bar=True,
            no_scrollbar=True,
        ):
            # add the texture
            dpg.add_image("_texture")

        # dpg.set_primary_window("_primary_window", True)

        # control window
        with dpg.window(
            label="Control",
            tag="_control_window",
            width=600,
            height=self.H,
            pos=[self.W, 0],
            no_move=True,
            no_title_bar=True,
        ):
            # button theme
            with dpg.theme() as theme_button:
                with dpg.theme_component(dpg.mvButton):
                    dpg.add_theme_color(dpg.mvThemeCol_Button, (23, 3, 18))
                    dpg.add_theme_color(dpg.mvThemeCol_ButtonHovered, (51, 3, 47))
                    dpg.add_theme_color(dpg.mvThemeCol_ButtonActive, (83, 18, 83))
                    dpg.add_theme_style(dpg.mvStyleVar_FrameRounding, 5)
                    dpg.add_theme_style(dpg.mvStyleVar_FramePadding, 3, 3)

            # timer stuff
            with dpg.group(horizontal=True):
                dpg.add_text("Infer time: ")
                dpg.add_text("no data", tag="_log_infer_time")

            # rendering options
            with dpg.collapsing_header(label="Rendering", default_open=True):
                # mode combo
                def callback_change_mode(sender, app_data):
                    self.mode = app_data
                    self.need_update = True

                dpg.add_combo(
                    ("image", "alpha"),
                    label="mode",
                    default_value=self.mode,
                    callback=callback_change_mode,
                )

                # fov slider
                def callback_set_fovy(sender, app_data):
                    self.cam.fovy = np.deg2rad(app_data)
                    self.need_update = True

                dpg.add_slider_int(
                    label="FoV (vertical)",
                    min_value=1,
                    max_value=120,
                    format="%d deg",
                    default_value=np.rad2deg(self.cam.fovy),
                    callback=callback_set_fovy,
                )

                def callback_set_gaussain_scale(sender, app_data):
                    self.gaussain_scale_factor = app_data
                    self.need_update = True

                dpg.add_slider_float(
                    label="gaussain scale",
                    min_value=0,
                    max_value=1,
                    format="%.2f",
                    default_value=self.gaussain_scale_factor,
                    callback=callback_set_gaussain_scale,
                )

        ### register camera handler

        def callback_camera_drag_rotate(sender, app_data):
            if not dpg.is_item_focused("_primary_window"):
                return

            dx = app_data[1]
            dy = app_data[2]

            self.cam.orbit(dx, dy)
            self.need_update = True

        def callback_camera_wheel_scale(sender, app_data):
            if not dpg.is_item_focused("_primary_window"):
                return

            delta = app_data

            self.cam.scale(delta)
            self.need_update = True

        def callback_camera_drag_pan(sender, app_data):
            if not dpg.is_item_focused("_primary_window"):
                return

            dx = app_data[1]
            dy = app_data[2]

            self.cam.pan(dx, dy)
            self.need_update = True

        with dpg.handler_registry():
            # for camera moving
            dpg.add_mouse_drag_handler(
                button=dpg.mvMouseButton_Left,
                callback=callback_camera_drag_rotate,
            )
            dpg.add_mouse_wheel_handler(callback=callback_camera_wheel_scale)
            dpg.add_mouse_drag_handler(
                button=dpg.mvMouseButton_Middle, callback=callback_camera_drag_pan
            )

        dpg.create_viewport(
            title="Gaussian3D",
            width=self.W + 600,
            height=self.H + (45 if os.name == "nt" else 0),
            resizable=False,
        )

        ### global theme
        with dpg.theme() as theme_no_padding:
            with dpg.theme_component(dpg.mvAll):
                # set all padding to 0 to avoid scroll bar
                dpg.add_theme_style(
                    dpg.mvStyleVar_WindowPadding, 0, 0, category=dpg.mvThemeCat_Core
                )
                dpg.add_theme_style(
                    dpg.mvStyleVar_FramePadding, 0, 0, category=dpg.mvThemeCat_Core
                )
                dpg.add_theme_style(
                    dpg.mvStyleVar_CellPadding, 0, 0, category=dpg.mvThemeCat_Core
                )

        dpg.bind_item_theme("_primary_window", theme_no_padding)

        dpg.setup_dearpygui()

        ### register a larger font
        # get it from: https://github.com/lxgw/LxgwWenKai/releases/download/v1.300/LXGWWenKai-Regular.ttf
        if os.path.exists("LXGWWenKai-Regular.ttf"):
            with dpg.font_registry():
                with dpg.font("LXGWWenKai-Regular.ttf", 18) as default_font:
                    dpg.bind_font(default_font)

        # dpg.show_metrics()

        dpg.show_viewport()

    def render(self):
        while dpg.is_dearpygui_running():
            # update texture every frame
            self.test_step()
            dpg.render_dearpygui_frame()


opt = tyro.cli(AllConfigs)

# load a saved ply and visualize
assert opt.test_path.endswith('.ply'), '--test_path must be a .ply file saved by infer.py'

gui = GUI(opt)
gui.render()