The problems of tone reproduction have been examined for still images since more than ten years. However, the problem has at least the same importance in interactive applications. If users navigate through virtual worlds with high dynamic range, the tone mapping should adapt to the current view, just as a video camera does when for instance moving from a dark to bright room.
We developed a practical way to achieve this adaptation per frame according to the current position and viewing direction of the user. By storing the tone mapping operator in a texture, which can be adapted on-the-fly, the tone reproduction can be adapted with very little overhead.
The following images show an application of that method to a reconstruction
of Zeus' temple in Olympia. The model has been created by the Foundation
of the Hellenic World in Athens. It is shown to museum visitors in
Athens in a CAVE, a room surrounded by projection walls, that gives the
audience a convincing impression of full immersion into the reconstructed
world. The video shows how the tone mapping adapts when the user moves
from the bright environment into the dark temple inside and back.
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A paper about this work has been published at EUROGRAPHICS 2000. See also "Tone Reproduction for Interactive Walkthroughs", by A. Scheel, M. Stamminger and H.-P. Seidel.