CLI, along with several examples, plus model downloading

examples/scenes/icesat2.toml

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+# ICESat-2 (752k triangles) in its 496 km orbit; the heavy model for benchmarks,
+# in an isometric view with Earth's limb behind it. Generated by
+# scripts/make-example-scenes.py; the model comes from scripts/fetch-models.sh.
+#
+#   resolved render --scene examples/scenes/icesat2.toml --preview icesat2.png
+
+sun = [105781668823, -105781668823, 0]
+moon = [0, 0, -3.844e8]
+
+[observer]
+position = [6874182.69, -103.11, 0.00]
+look_at = [6874137.00, 0.00, 0.00]
+up = [1, 0, 0]
+
+[[target]]
+model = "../models/nasa/icesat2.glb"
+scale = 1.0
+position = [6874133.2074, 2.1303, -1.3429]
+attitude = [0.204578316, -0.623275321, 0.333957893, -0.676866097]