First vertical slice for the SDF viewer

Keywords: SDF · entities · first slice

Draws a finite Line and a Sphere from pytanga.geometry in the ray-marched signed-distance-function viewer, then carves a partial bite out of the sphere with a second, subtracting sphere.

Run

uv run python py/examples/viz/sdf/entities.py

Source

viz/sdf/entities.py

Code

# SPDX-License-Identifier: Apache-2.0
# Copyright 2021 Christian Perwass

"""entities.py — First vertical slice for the SDF viewer.

Draws a finite ``Line`` and a ``Sphere`` from ``pytanga.geometry`` in the
ray-marched signed-distance-function viewer, then carves a partial bite out of
the sphere with a second, subtracting sphere.

Run with:  uv run python py/examples/viz/sdf/entities.py

Keywords: SDF, entities, first slice
"""

from pytanga.geometry import Line, Point, Sphere
from pytanga.viz.sdf import SdfVisualizer

viz = SdfVisualizer(title="Tanga SDF — Line + Sphere − Sphere")

# A finite line segment (origin + length via from_points).
viz.add(
    Line.from_points(Point(-3, 0, 0), Point(3, 0, 0)),
    color="#44ff44",
    thickness=0.08,
)

# A filled sphere.
viz.add(
    Sphere(Point(0, 1.5, 0), radius=1.5),
    color="#ffaa00",
)

# A second sphere that partially subtracts from the orange sphere. It overlaps
# the sphere's surface on the upper-right, so `combine="subtract"` carves a
# concave bite out of it (the carved wall keeps the orange sphere's color).
viz.add(
    Sphere(Point(1.2, 2.0, 0), radius=0.9),
    combine="subtract",
)

print("Opening the SDF viewer. A green line and an orange sphere with a carved")
print(
    "bite should be visible; drag to orbit, right/middle-drag to pan, scroll to zoom."
)

viz.show()
viz.wait()