Instancing

Example rendering the same mesh object multiple times, using instancing.

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()

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

geometry = gfx.torus_knot_geometry(1, 0.3, 128, 32)
geometry.texcoords.data[:, 0] *= 10  # stretch the texture
material = gfx.MeshPhongMaterial(map=tex)
obj = gfx.InstancedMesh(geometry, material, 100)
scene.add(obj)


# Set matrices. Note that these are sub-transforms of the mesh's own matrix.
for y in range(10):
    for x in range(10):
        m = la.mat_from_translation((y * 2, x * 2, 0))
        obj.set_matrix_at(x + y * 10, m)


camera = gfx.PerspectiveCamera(70, 1)
camera.local.position = (9, 9, 15)

scene.add(gfx.AmbientLight())
scene.add(camera.add(gfx.DirectionalLight()))


def animate():
    rot = la.quat_from_euler((0.0071, 0.01), order="XY")
    obj.local.rotation = la.quat_mul(rot, obj.local.rotation)

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


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