Render Motion to Video File

This example uses Imageio (installed both imageio and imageio-ffmpeg) to combine frames rendered by the opynsim.graphics module into a viewable .mp4 file.

import opynsim as opyn
import opynsim.graphics
import imageio  # from `imageio` and `imageio-ffmpeg` packages

# Load + compile an `opynsim.Model` from an `osim` file.
model = opyn.read_osim("some.osim").compile()

# Load an associated motion from an `sto file` into an `opynsim.DataFrame`.
sto = opyn.read_sto("some.sto")

# Create `opynsim.ModelStates` of the `opynsim.Model` from the data frame.
states = model.states_from_data_frame(sto)

# Render each state as a frame in `output.mp4`.
with imageio.get_writer("output.mp4", fps=60) as writer:
    for state in states:
        model.realize(state, opyn.STAGE_REPORT) # Required for rendering
        texture_2d = opyn.graphics.render_model_in_state(model, state)
        pixels_ndarray = render.pixels_rgb24()
        writer.append_data(pixels_ndarray)