In this paper we present a set of efficient image based rendering methods capable of rendering multiple frames per second on a PC. The first method warps Sprites with Depth representing smooth surfaces without the gaps found in other techniques. A second method for more general scenes performs warping from an intermediate representation called a Layered Depth Image (LDI). An LDI is a view of the scene from a single input camera view, but with multiple pixels along each line of sight. The size of the representation grows only linearly with the observed depth complexity in the scene. Moreover, because the LDI data are represented in a single image coordinate system, McMillan's warp ordering algorithm can be successfully adapted. As a result, pixels are drawn in the output image in backto-front order. No z-buffer is required, so alpha-compositing can be done efficiently without depth sorting. This makes splatting an efficient solution to the resampling problem.

We present a simple stochastic system for non-periodically tiling the plane with a small set of Wang Tiles. The tiles may be filled with texture, patterns, or geometry that when assembled create a continuous representation. The primary advantage of using Wang Tiles is that once the tiles are filled, large expanses of non-periodic texture (or patterns or geometry) can be created as needed very efficiently at runtime. Wang Tiles are squares in which each edge is assigned a color. A valid tiling requires all shared edges between tiles to have matching colors. We present a new stochastic algorithm to nonperiodically tile the plane with a small set of Wang Tiles at runtime. Furthermore, we present new methods to fill the tiles with 2D texture, 2D Poisson distributions, or 3D geometry to efficiently create at runtime as much non-periodic texture (or distributions, or geometry) as needed. We leverage previous texture synthesis work and adapt it to fill Wang Tiles. We demonstrate how to fill individual tiles with Poisson distributions that maintain their statistical properties when combined. These are used to generate a large arrangement of plants or other objects on a terrain. We show how such environments can be rendered efficiently by pre-lighting the individual Wang Tiles containing the geometry. We also extend the definition of Wang Tiles to include a coding of the tile corners to allow discrete objects to overlap more than one edge. The larger set of tiles provides increased degrees of freedom.

We present a new method that utilizes path coherence to accelerate walkthroughs of geometrically complex static scenes. As a preprocessing step, our method constructs a BSP-tree that hierarchically partitions the geometric primitives in the scene. In the course of a walkthrough, images of nodes at various levels of the hierarchy are cached for reuse in subsequent frames. A cached image is reused by texture-mapping it onto a single quadrilateral that is drawn instead of the geometry contained in the corresponding node. Visual artifacts are kept under control by using an error metric that quantifies the discrepancy between the appearance of the geometry contained in a node and the cached image. The new method is shown to achieve speedups of an order of magnitude for walkthroughs of a complex outdoor scene, with little or no loss in rendering quality.

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We present a simple stochastic system for non-periodically tiling the plane with a small set of Wang Tiles. The tiles may be filled with texture, patterns, or geometry that when assembled create a continuous representation. The primary advantage of using Wang Tiles is that once the tiles are filled, large expanses of non-periodic texture (or patterns or geometry) can be created as needed very efficiently at runtime. Wang Tiles are squares in which each edge is assigned a color. A valid tiling requires all shared edges between tiles to have matching colors. We present a new stochastic algorithm to nonperiodically tile the plane with a small set of Wang Tiles at runtime. Furthermore, we present new methods to fill the tiles with 2D texture, 2D Poisson distributions, or 3D geometry to efficiently create at runtime as much non-periodic texture (or distributions, or geometry) as needed. We leverage previous texture synthesis work and adapt it to fill Wang Tiles. We demonstrate how to fill individual tiles with Poisson distributions that maintain their statistical properties when combined. These are used to generate a large arrangement of plants or other objects on a terrain. We show how such environments can be rendered efficiently by pre-lighting the individual Wang Tiles containing the geometry. We also extend the definition of Wang Tiles to include a coding of the tile corners to allow discrete objects to overlap more than one edge. The larger set of tiles provides increased degrees of freedom.