Results 1  10
of
39
View Interpolation for Image Synthesis
"... Imagespace simplifications have been used to accelerate the calculation of computer graphic images since the dawn of visual simulation. Texture mapping has been used to provide a means by which images may themselves be used as display primitives. The work reported by this paper endeavors to carry t ..."
Abstract

Cited by 522 (0 self)
 Add to MetaCart
Imagespace simplifications have been used to accelerate the calculation of computer graphic images since the dawn of visual simulation. Texture mapping has been used to provide a means by which images may themselves be used as display primitives. The work reported by this paper endeavors to carry this concept to its logical extreme by using interpolated images to portray threedimensional scenes. The specialeffects technique of morphing, which combines interpolation of texture maps and their shape, is applied to computing arbitrary intermediate frames from an array of prestored images. If the images are a structured set of views of a 3D object or scene, intermediate frames derived by morphing can be used to approximate intermediate 3D transformations of the object or scene. Using the view interpolation approach to synthesize 3D scenes has two main advantages. First, the 3D representation of the scene may be replaced with images. Second, the image synthesis time is independent of the scene complexity. The correspondence between images, required for the morphing method, can be predetermined automatically using the range data associated with the images. The method is further accelerated by a quadtree decomposition and a viewindependent visible priority. Our experiments have shown that the morphing can be performed at interactive rates on today’s highend personal computers. Potential applications of the method include virtual holograms, a walkthrough in a virtual environment, imagebased primitives and incremental rendering. The method also can be used to greatly accelerate the computation of motion blur and soft shadows cast by area light sources.
A survey of visibility for walkthrough applications
 IEEE TRANSACTIONS ON VISUALIZATION AND COMPUTER
, 2003
"... Visibility algorithms for walkthrough and related applications have grown into a significant area, spurred by the growth in the complexity of models and the need for highly interactive ways of navigating them. In this survey, we review the fundamental issues in visibility and conduct an overview of ..."
Abstract

Cited by 145 (8 self)
 Add to MetaCart
Visibility algorithms for walkthrough and related applications have grown into a significant area, spurred by the growth in the complexity of models and the need for highly interactive ways of navigating them. In this survey, we review the fundamental issues in visibility and conduct an overview of the visibility culling techniques developed in the last decade. The taxonomy we use distinguishes between pointbased and fromregion methods. Pointbased methods are further subdivided into object and imageprecision techniques, while fromregion approaches can take advantage of the cellandportal structure of architectural environments or handle generic scenes.
Near realtime shadow generation using bsp trees
 Computer Graphics
, 1989
"... This paper describes an objectspace shadow generation algorithm for static polygonal environments illuminated by movable point light sources. The algorithm can be easily implemented on any graphics system that provides fast polygon scanconversion and achieves near realtime performance for environ ..."
Abstract

Cited by 80 (0 self)
 Add to MetaCart
This paper describes an objectspace shadow generation algorithm for static polygonal environments illuminated by movable point light sources. The algorithm can be easily implemented on any graphics system that provides fast polygon scanconversion and achieves near realtime performance for environments of modest size. It combines elements of two kinds of current shadow generation algorithms: twopass objectspace approaches and shadow volume approaches. For each light source a Binary Space Partitioning (BSP) tree is constructed that represents the shadow volume of the polygons facing it. As each polygon's contribution to a light source's shadow volume is determined, the polygon's shadowed and lit fragments are computed by filtering it down the shadow volume BSP tree. The polygonal scene with its computed shadows can be rendered with any polygonbased visiblesurface algorithm. Since the shadow volumes and shadows are computed in object space, they can be used for further analysis of the scene. Pseudocode is provided, along with pictures and timings from an interactive implementation.
An introduction to parallel rendering
 Parallel Computing
, 1997
"... In computer graphics, rendering is the process by which an abstract description of a scene is converted to an image. When the scene is complex, or when highquality images or high frame rates are required, the rendering process becomes computationally demanding. To provide the necessary levels of pe ..."
Abstract

Cited by 39 (2 self)
 Add to MetaCart
In computer graphics, rendering is the process by which an abstract description of a scene is converted to an image. When the scene is complex, or when highquality images or high frame rates are required, the rendering process becomes computationally demanding. To provide the necessary levels of performance, parallel computing techniques must be brought to bear. Although parallelism has been exploited in computer graphics since the early days of the field, its initial use was primarily in specialized applications. The VLSI revolution of the late 1970Õs and the advent of scalable parallel computers during the late 1980Õs changed this situation. Today, parallel hardware is routinely used in graphics workstations, and numerous softwarebased rendering systems have been developed for generalpurpose parallel architectures. This article provides a broad introduction to the subject of parallel rendering, encompassing both hardware and software systems. The focus is on the underlying concepts and the issues which arise in the design of parallel rendering algorithms and systems. We examine the different types of parallelism and how they can be applied in rendering applications. Concepts from parallel computing, such as data decomposition, task granularity, scalability, and load balancing, are considered in relation to the rendering
Visibility Sorting and Compositing without Splitting for Image Layer Decomposition
 In Proceedings of the 25th Annual Conference on Computer Graphics & Interactive Techniques
, 1998
"... We present an efficient algorithm for visibility sorting a set of moving geometric objects into a sequence of image layers which are composited to produce the final image. Instead of splitting the geometry as in previous visibility approaches, we detect mutual occluders and resolve them using an app ..."
Abstract

Cited by 32 (3 self)
 Add to MetaCart
We present an efficient algorithm for visibility sorting a set of moving geometric objects into a sequence of image layers which are composited to produce the final image. Instead of splitting the geometry as in previous visibility approaches, we detect mutual occluders and resolve them using an appropriate image compositing expression or merge them into a single layer. Such an algorithm has many applications in computer graphics; we demonstrate two: rendering acceleration using image interpolation and visibilitycorrect depth of field using image blurring. We propose a new, incremental method for identifying mutually occluding sets of objects and computing a visibility sort among these sets. Occlusion queries are accelerated by testing on convex bounding hulls; less conservative tests are also discussed. Kdtrees formed by combinations of directions in object or image space provide an initial cull on potential occluders, and incremental collision detection algorithms are adapted to resolve pairwise occlusions, when necessary. Mutual occluders are further analyzed to generate an image compositing expression; in the case of nonbinary occlusion cycles, an expression can always be generated without merging the objects into a single layer. Results demonstrate that the algorithm is practical for realtime animation of scenes involving hundreds of objects each comprising hundreds or thousands of polygons.
Cylindrical Static and Kinetic Binary Space Partitions
, 1997
"... We describe the first known algorithm for efficiently maintaining a Binary Space Partition (BSP) for n continuously moving segments in the plane. Under reasonable assumptions on the motion, we show that the total number of times the BSP changes is O(n 2 ), and that we can update the BSP in O(log n ..."
Abstract

Cited by 29 (15 self)
 Add to MetaCart
We describe the first known algorithm for efficiently maintaining a Binary Space Partition (BSP) for n continuously moving segments in the plane. Under reasonable assumptions on the motion, we show that the total number of times the BSP changes is O(n 2 ), and that we can update the BSP in O(log n) expected time per change. We also consider the problem of constructing a BSP for n triangles in R 3 . We present a randomized algorithm that constructs a BSP of expected size O(n 2 ) in O(n 2 log 2 n) expected time. We also describe a deterministic algorithm that constructs a BSP of size O((n + k) log n) and height O(log n) in O((n + k) log 2 n) time, where k is the number of intersection points between the edges of the projections of the triangles onto the xyplane. 1 Introduction The Binary Space Partition (BSP, also known as BSP tree), originally proposed by Schumacker et al. [26] and further refined by Fuchs et al. [16], is a hierarchical partitioning of space widely used i...
Hierarchical BackFace Computation
 Eurographics Rendering Workshop
, 1996
"... We presentasublinear algorithm for computing and culling backfacing polygons that yields a signi#cant performance improvement in the interactive rendering of large polygonal models. The algorithm partitions a polygonal model it into hierarchical clusters based on the normals and positions of the p ..."
Abstract

Cited by 24 (0 self)
 Add to MetaCart
We presentasublinear algorithm for computing and culling backfacing polygons that yields a signi#cant performance improvement in the interactive rendering of large polygonal models. The algorithm partitions a polygonal model it into hierarchical clusters based on the normals and positions of the polygons. It does not explicitly compute all the backfacing polygons but rather decides, in expectedconstant time, whether an entire cluster is backfacing. As a preprocessing step, the algorithm partitions the space into regions with respect to each cluster. During rendering, it exploits frametoframe coherence to track the viewpoint. The algorithm has been applied to a number of models and its performance is a function of number of clusters, the depth of the hierarchies, and the characteristics of the graphics system. In practice, we are able to cull 30 , 55# of the polygons in about 5 , 10# of the total CPU time per frame on an SGI Indigo2 Extreme for models composed of tens of tho...
Binary space partitions for fat rectangles
 in: Proc. 37th Annu. IEEE Sympos. Found. Comput. Sci
, 1996
"... sizen2O(plogn) We consider the practical problem of constructing binary space partitions (BSPs) for a setSofnorthogonal, nonintersecting, twodimensional rectangles inIR3such that the aspect ratio of each rectangle inSis at most, for some constant1. We present ann2O(plogn)time algorithm to build a ..."
Abstract

Cited by 23 (6 self)
 Add to MetaCart
sizen2O(plogn) We consider the practical problem of constructing binary space partitions (BSPs) for a setSofnorthogonal, nonintersecting, twodimensional rectangles inIR3such that the aspect ratio of each rectangle inSis at most, for some constant1. We present ann2O(plogn)time algorithm to build a binary space partition of forS. We also show that ifmof thenrectangles inShave aspect ratios greater than, we can construct a BSP of sizenpm2O(plogn)forSinnpm2O(plogn)time. The constants of proportionality in the bigoh terms are linear inlog. We extend these results to cases in which the input contains nonorthogonal or intersecting objects.
Kinetic Binary Space Partitions for Intersecting Segments and Disjoint Triangles (Extended Abstract)
, 1998
"... We describe randomized algorithms for efficiently maintaining a binary space partition of continuously moving, possibly intersecting, line segments in the plane, and of continuously moving but disjoint triangles in space. Our twodimensional BSP has depth O(log n) and size O(n log n + k) and can be ..."
Abstract

Cited by 20 (10 self)
 Add to MetaCart
We describe randomized algorithms for efficiently maintaining a binary space partition of continuously moving, possibly intersecting, line segments in the plane, and of continuously moving but disjoint triangles in space. Our twodimensional BSP has depth O(log n) and size O(n log n + k) and can be constructed in expected O(n log² n + k log n) time, where k is the number of intersecting pairs. We can detect combinatorial changes to our BSP caused by the motion of the segments, and we can update our BSP in expected O(log n) time per change. Our threedimensional BSP has depth O(log n), size O(n log² n+k 0 ), construction time O(n log³ n+k 0 log n), and update time O(log² n) (all expected), where k 0 is the number of intersections between pairs of edges in the xy projection of the triangles. Under reasonable assumptions about the motion of the segments or triangles, the expected number of number o...