Validate Skybox

This validates that the skybox background is rendered correctly, as well as that the environment-map matches that background. Therefore it also covers the internal cube-camera-renderer.

Note that the blue -Z side is marked “back”, but since camera’s look down the -Z direction, it’d be what the camera would see if it was not rotated.

import os

import numpy as np
import imageio.v3 as iio
import pygfx as gfx
from pathlib import Path
from wgpu.gui.auto import WgpuCanvas, run

try:
    data_dir = Path(__file__).parents[1] / "data"
except NameError:
    data_dir = Path(os.getcwd()).parent / "data"  # compat with sphinx-gallery

data = iio.imread(data_dir / "cubemap.jpg")

h = data.shape[0] // 3
w = data.shape[1] // 4

"""
The layout of the example cubemap looks like this:
 ┌────┬────┬────┬────┐
 │    │ +Y │    │    │
 ├────┼────┼────┼────┤
 │ -X │ +Z │ +X │ -Z │
 ├────┼────┼────┼────┤
 │    │ -Y │    │    │
 └────┴────┴────┴────┘
 """
posx = np.ascontiguousarray(data[1 * h : 2 * h, 2 * w : 3 * w])
negx = np.ascontiguousarray(data[1 * h : 2 * h, 0 * w : 1 * w])
posy = np.ascontiguousarray(data[0 * h : 1 * h, 1 * w : 2 * w])
negy = np.ascontiguousarray(data[2 * h : 3 * h, 1 * w : 2 * w])
posz = np.ascontiguousarray(data[1 * h : 2 * h, 1 * w : 2 * w])
negz = np.ascontiguousarray(data[1 * h : 2 * h, 3 * w : 4 * w])

datas = [posx, negx, posy, negy, posz, negz]

tex = gfx.Texture(np.stack(datas, axis=0), dim=2, size=(w, h, 6), generate_mipmaps=True)

canvas = WgpuCanvas(size=(640, 640))
renderer = gfx.renderers.WgpuRenderer(canvas)

scene = gfx.Scene()

background = gfx.Background(None, gfx.BackgroundSkyboxMaterial(map=tex))
scene.add(background)

mesh = gfx.Mesh(
    gfx.sphere_geometry(2, 64, 64),
    gfx.MeshStandardMaterial(roughness=0.01, metalness=1, side="Front"),
)
mesh.material.env_map = tex
scene.add(mesh)

camera = gfx.PerspectiveCamera(90)
camera.local.position = (2, 3, 4)
camera.show_pos(mesh)

controller = gfx.OrbitController(camera, register_events=renderer)

renderer.request_draw(lambda: renderer.render(scene, camera))

if __name__ == "__main__":
    print(__doc__)
    run()