A few images rendered with sprout, a CPU-based path tracer. The source can be found on github.

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[ Imperial Star Destroyer - Imperator, Tie Fighter ]

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[ 4060.b Spaceship, Photogrammetic Rock ]

The grass is procedurally generated.

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[ San Miguel ]

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[ Fir tree ]

The aurora is procedurally generated, inspired by the paper Simulating the Aurora Borealis.

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[ Amazon Lumberyard Bistro ]

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[ Happy Buddha, Cycles B.M.P.S, Asian Dragon, Candle, Stanford Bunny ]

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[ Transi de René de Chalon ]

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[ Alpine Landscape ]

The lighting consists almost entirely out of caustics, which are rendered with light-tracing and photon mapping.

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[ Disney Cloud ]