the bidirectional texture function (BTF) is a 6D function that can describe textures arising from both spatially-variant surface reflectance and surface mesostructures. In this paper, we present an algorithm for synth...
详细信息
ISBN:
(纸本)9781581135213
the bidirectional texture function (BTF) is a 6D function that can describe textures arising from both spatially-variant surface reflectance and surface mesostructures. In this paper, we present an algorithm for synthesizing the BTF on an arbitrary surface from a sample BTF. A main challenge in surface BTF synthesis is the requirement of a consistent mesostructure on the surface, and to achieve that we must handle the large amount of data in a BTF sample. Our algorithm performs BTF synthesis based on surface textons, which extract essential information from the sample BTF to facilitate the synthesis. We also describe a general search strategy, called the k-coherent search, for fast BTF synthesis using surface textons. A BTF synthesized using our algorithm not only looks similar to the BTF sample in all viewing/lightning conditions but also exhibits a consistent mesostructure when viewing and lighting directions change. Moreover, the synthesized BTF fits the target surface naturally and seamlessly. We demonstrate the effectiveness of our algorithm with sample BTFs from various sources, including those measured from real-world textures.
A Texture Atlas is an efficient color representation for 3D Paint Systems. the model to be textured is decomposed into charts homeomorphic to discs, each chart is parameterized, and the unfolded charts are packed in t...
详细信息
ISBN:
(纸本)9781581135213
A Texture Atlas is an efficient color representation for 3D Paint Systems. the model to be textured is decomposed into charts homeomorphic to discs, each chart is parameterized, and the unfolded charts are packed in texture space. Existing texture atlas methods for triangulated surfaces suffer from several limitations, requiring them to generate a large number of small charts with simple borders. the discontinuities between the charts cause artifacts, and make it difficult to paint large areas with regular patterns. In this paper, our main contribution is a new quasi-conformal parameterization method, based on a least-squares approximation of the Cauchy-Riemann equations. the so-defined objective function minimizes angle deformations, and we prove the following properties: the minimum is unique, independent of a similarity in texture space, independent of the resolution of the mesh and cannot generate triangle flips. the function is numerically well behaved and can therefore be very efficiently minimized. Our approach is robust, and can parameterize large charts with complex borders. We also introduce segmentation methods to decompose the model into charts with natural shapes, and a new packing algorithm to gather them in texture space. We demonstrate our approach applied to paint both scanned and modeled data sets.
Polygon meshes are a popular representation in computergraphics. they efficiently provide delineations of complex 3D shapes. However, their irregular structure hinders mesh analysis efforts in deep learning framework...
详细信息
In this paper we describe how to simulate geometrically complex, interactive, physically-based, volumetric, dynamic deformation models with negligible main CPU costs. this is achieved using a Dynamic Response Texture,...
详细信息
ISBN:
(纸本)9781581135213
In this paper we describe how to simulate geometrically complex, interactive, physically-based, volumetric, dynamic deformation models with negligible main CPU costs. this is achieved using a Dynamic Response Texture, or DyRT, that can be mapped onto any conventional animation as an optional rendering stage using commodity graphics hardware. the DyRT simulation process employs precomputed modal vibration models excited by rigid body motions. We present several examples, with an emphasis on bone-based character animation for interactive applications.
the proceedings contain 58 papers. the topics discussed include: surface reconstruction from non-parallel curve networks;high-resolution volumetric computation of offset surfaces with feature preservation;reduced dept...
the proceedings contain 58 papers. the topics discussed include: surface reconstruction from non-parallel curve networks;high-resolution volumetric computation of offset surfaces with feature preservation;reduced depth and visual hulls of complex 3D scenes;Render2MPEG: a perception-based framework towards integrating rendering and video compression;apparent greyscale: a simple and fast conversion to perceptually accurate images and video;effect of character animacy and preparatory motion on perceptual magnitude of errors in ballistic motion;lighting and occlusion in a wave-based framework;GPU accelerated direct volume rendering on an interactive light field display;curvature-domain shape processing;spectral geometry processing with manifold harmonics;fast force field approximation and its application to skeletonization of discrete 3D objects;and sketch-based procedural surface modeling and compositing using surface trees.
We discuss a method for creating animations that allows the animator to sketch an animation by setting a small number of keyframes on a fraction of the possible degrees of freedom. Motion capture data is then used to ...
详细信息
ISBN:
(纸本)9781581135213
We discuss a method for creating animations that allows the animator to sketch an animation by setting a small number of keyframes on a fraction of the possible degrees of freedom. Motion capture data is then used to enhance the animation. Detail is added to degrees of freedom that were keyframed, a process we call texturing. Degrees of freedom that were not keyframed are synthesized. the method takes advantage of the fact that joint motions of an articulated figure are often correlated, so that given an incomplete data set, the missing degrees of freedom can be predicted from those that are present.
We present a level set framework for implementing editing operators for surfaces. Level set models are deformable implicit surfaces where the deformation of the surface is controlled by a speed function in the level s...
详细信息
ISBN:
(纸本)9781581135213
We present a level set framework for implementing editing operators for surfaces. Level set models are deformable implicit surfaces where the deformation of the surface is controlled by a speed function in the level set partial differential equation. In this paper we define a collection of speed functions that produce a set of surface editing operators. the speed functions describe the velocity at each point on the evolving surface in the direction of the surface normal. All of the information needed to deform a surface is encapsulated in the speed function, providing a simple, unified computational framework. the user combines pre-defined building blocks to create the desired speed function. the surface editing operators are quickly computed and may be applied both regionally and globally. the level set framework offers several advantages. 1) By construction, self-intersection cannot occur, which guarantees the generation of physically-realizable, simple, closed surfaces. 2) Level set models easily change topological genus, and 3) are free of the edge connectivity and mesh quality problems associated with mesh models. We present five examples of surface editing operators: blending, smoothing, sharpening, openings/closings and embossing. We demonstrate their effectiveness on several scanned objects and scan-converted models.
Shipbuilding industry is undergoing a change, in which many European shipyards focus on special purpose vessels. this field of shipbuilding places very high demands on engineering, commissioning and operation of the v...
详细信息
A teaching curve design tool is a component of the software tools used in computing with a geometric course being developed under the support of the National Science Foundation. Curve design is important in computer g...
详细信息
A teaching curve design tool is a component of the software tools used in computing with a geometric course being developed under the support of the National Science Foundation. Curve design is important in computergraphics, animation, and computer aided design. Unfortunately, curve design requires very involved mathematics even though many curve design concepts are intuitive. As a result, it is a challenging job for instructors teaching curves and surfaces in computergraphics, computer aided design, and other related courses.
In the present paper, the bow of the striking ship is assumed to collide the midship part of the struck ship. In the previous model, the striking ship is approximated by a lumped mass system, and the struck ship by on...
详细信息
ISBN:
(纸本)9780791849101
In the present paper, the bow of the striking ship is assumed to collide the midship part of the struck ship. In the previous model, the striking ship is approximated by a lumped mass system, and the struck ship by one mass and one spring system. In the present model, the struck ship is replaced by a system composed of rigid bars and elasto-plastic hinges. this model not only can express the response of the struck ship more reasonably, but also dose not require much time for numerical simulation. Some numerical results are shown to show the effectiveness of braking panels.
.jpg?site=8fa65c6403e3f8b5b3923814eda18bd0)
暂无评论