Tiny Image Validation

This example shows the ability to render different images of small sizes from 32x32 to 1x1 pixels in both RGB and grayscale formats.

1x1 pixel images might seem strange but can occurs in algorithm development where the applicability of an algorithm is tested against extreme bounds.

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


canvas = WgpuCanvas(size=(180 * 5, 40 * 5))
renderer = gfx.renderers.WgpuRenderer(canvas)
scene = gfx.Scene()
camera = gfx.OrthographicCamera(180, 40)
camera.local.y = 16
camera.local.scale_y = -1
camera.local.x = 176 / 2

astronaut = iio.imread("imageio:astronaut.png")
# astronaut is a 512x512 image, resize it to 32x32
# anti-aliasing is bad, but it shows funny effects too!
astronaut_32x32 = astronaut[::16, ::16]
astronaut_32x32_grayscale = np.sum(
    np.asarray([1.0, 1.0, 1.0]) / 3 * astronaut_32x32,
    axis=-1,
).astype(np.uint8)

position_rgb = 0
position_gray = 176
for i in [
    32,
    16,
    8,
    4,
    2,
    1,
]:
    image_rgb = astronaut_32x32[:: 32 // i, :: 32 // i]
    image_gfx = gfx.Image(
        gfx.Geometry(grid=gfx.Texture(image_rgb, dim=2)),
        gfx.ImageBasicMaterial(clim=(0, 255)),
    )
    image_gfx.local.x = position_rgb
    position_rgb += i + 10
    scene.add(image_gfx)

    image_gray = astronaut_32x32_grayscale[:: 32 // i, :: 32 // i]
    image_gfx = gfx.Image(
        gfx.Geometry(grid=gfx.Texture(image_gray, dim=2)),
        gfx.ImageBasicMaterial(clim=(0, 255)),
    )
    image_gfx.local.x = position_gray - i
    image_gfx.local.y = 32 - i
    scene.add(image_gfx)
    position_gray -= i + 10

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

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