Color Picking

Example showing picking the color from the scene. Depending on the object being clicked, more detailed picking info is available.

import numpy as np
import imageio.v3 as iio
from rendercanvas.auto import RenderCanvas, loop
import pygfx as gfx
import pylinalg as la


canvas = RenderCanvas()
renderer = gfx.renderers.WgpuRenderer(canvas)
scene = gfx.Scene()

dark_gray = np.array((169, 167, 168, 255)) / 255
light_gray = np.array((100, 100, 100, 255)) / 255
background = gfx.Background.from_color(light_gray, dark_gray)
scene.add(background)

im = iio.imread("imageio:astronaut.png").astype(np.float32) / 255
tex = gfx.Texture(im, dim=2)

geometry = gfx.box_geometry(200, 200, 200)
material = gfx.MeshBasicMaterial(map=tex, pick_write=True)
cube = gfx.Mesh(geometry, material)
scene.add(cube)

# camera = gfx.OrthographicCamera(300, 300)
camera = gfx.PerspectiveCamera(70, 16 / 9)
camera.show_object(cube, scale=1.5)


@renderer.add_event_handler("pointer_down")
def handle_event(event):
    info = event.pick_info
    for key, val in info.items():
        print(key, "=", val)


def animate():
    rot = la.quat_from_euler((0.005, 0.01), order="XY")
    cube.local.rotation = la.quat_mul(rot, cube.local.rotation)

    renderer.render(scene, camera)
    canvas.request_draw()


if __name__ == "__main__":
    canvas.request_draw(animate)
    loop.run()

Interactive example

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