Camera Flyover

The viewer handle is scriptable enough that a flyover can still be just a frame loop, but TV17 also adds reusable terrain rig authoring that bakes straight into CameraAnimation.

Ingredients

• forge3d.open_viewer_async()

• ViewerHandle.set_orbit_camera()

• ViewerHandle.snapshot()

• forge3d.camera_rigs

Low-Level Baseline

import forge3d as f3d

with f3d.open_viewer_async(terrain_path=f3d.fetch_dem("rainier")) as viewer:
    for step, phi in enumerate(range(0, 360, 20)):
        viewer.set_orbit_camera(phi_deg=phi, theta_deg=50, radius=5400)
        viewer.snapshot(f"frames/frame-{step:03d}.png")

Rig Demo

For reusable orbit, rail, and follow shots, use examples/terrain_camera_rigs_demo.py. It bakes the rig to the same CameraAnimation object used by the low-level loop above:

import forge3d as f3d
from forge3d.camera_rigs import TerrainOrbitRig, TerrainClearance
from forge3d.terrain_scatter import TerrainScatterSource

source = TerrainScatterSource(f3d.mini_dem(), terrain_width=256.0)
rig = TerrainOrbitRig(
    target_xz=(128.0, 128.0),
    duration=6.0,
    radius=60.0,
    phi_start_deg=20.0,
    phi_end_deg=320.0,
    clearance=TerrainClearance(minimum_height=4.0),
)
animation = rig.bake(source, samples_per_second=60)

The demo ships three preset shots:

• orbit_rainier

• rail_luxembourg

• follow_rainier

Example:

python examples/terrain_camera_rigs_demo.py --preset rail_luxembourg