公开(公告)号：US20070257913A1

公开(公告)日：2007-11-08

申请号：US11825918

申请日：2007-07-09

申请人： Peter-Pike Sloan ,  John Snyder ,  Jan Kautz

发明人： Peter-Pike Sloan ,  John Snyder ,  Jan Kautz

IPC分类号： G06T15/60

CPC分类号： G06T15/506

摘要： Real-time image rendering of diffuse and glossy objects in low-frequency lighting environments captures soft shadows, interreflections, and caustics. As a preprocess, a global transport simulator creates functions over the object's surface representing transfer of arbitrary, low-frequency source lighting into exiting radiance, but including global effects like shadowing and interreflection from the object onto itself. At run-time, these transfer functions are applied to the actual source lighting. Dynamic, local lighting is handled by sampling close to the object at every frame; the object can also be rigidly rotated with respect to the lighting and vice versa. Lighting and transfer functions are represented using low-order spherical harmonics. Functions for radiance transfer from a dynamic lighting environment through a preprocessed object to neighboring points in space further allow cast soft shadows and caustics from rigidly moving casters onto arbitrary, dynamic receivers.

公开(公告)号：US20060214931A1

公开(公告)日：2006-09-28

申请号：US11089265

申请日：2005-03-22

申请人： John Snyder ,  Ben Luna ,  Peter-Pike Sloan

发明人： John Snyder ,  Ben Luna ,  Peter-Pike Sloan

IPC分类号： G06T15/50

CPC分类号： G06T15/50

摘要： Computer graphics image rendering techniques render images using a precomputed radiance transfer (PRT) to model local effects such as bumps, wrinkles, or other detailed features on an arbitrarily deformable model's surface. The techniques apply zonal harmonics (ZH) which approximate spherical functions as sums of circularly symmetric functions around different axes. By spatially varying both the axes and coefficients of these basis functions, approximations can fit to spatially varying transfer signals. Compared to the spherical harmonic (SH) basis, the ZH basis yields a more compact approximation, and can be rotated at a low computational expense suitable for dense per-vertex or per-pixel evaluation. This allows PRT to be mapped onto deforming models which re-orient the local coordinate frame.

公开(公告)号：US20050253844A1

公开(公告)日：2005-11-17

申请号：US11185102

申请日：2005-07-19

申请人： Hugues Hoppe ,  John Snyder ,  Pedro Sander ,  Steven Gortler

发明人： Hugues Hoppe ,  John Snyder ,  Pedro Sander ,  Steven Gortler

IPC分类号： G06T17/00 ,  G06T17/20 ,  G09G5/00

CPC分类号： G06T17/20 ,  G06T17/205

摘要： Systems and methods are provided for providing a fine-to-coarse look ahead in connection with parametrization in a graphics system. The use of a variety of parametrization metrics may be supplemented and improved by the fine-to-coarse look ahead techniques of the invention. First, the metric of a parametrization is minimized using a coarse-to-fine hierarchical solver, and then accelerated with a fine-to-coarse propagation. The resulting parametrizations have increased texture resolution in surface regions with greater signal detail at all levels of detail in the progressive mesh sequence.

摘要翻译： 提供的系统和方法用于提供与图形系统中的参数化相关的精细到粗略的前瞻性。 可以通过本发明的精细到粗略的前瞻技术来补充和改进各种参数化度量的使用。 首先，使用粗到细分级求解器将参数化的度量最小化，然后以精细到粗糙的传播加速。 所得到的参数化在渐进网格序列的所有细节级别具有更大的信号细节的表面区域中增加了纹理分辨率。

公开(公告)号：US20050134605A1

公开(公告)日：2005-06-23

申请号：US11062688

申请日：2005-02-22

申请人： Hugues Hoppe ,  John Snyder ,  Pedro Sander ,  Steven Gortler

发明人： Hugues Hoppe ,  John Snyder ,  Pedro Sander ,  Steven Gortler

IPC分类号： G06T15/50 ,  G09G5/00

CPC分类号： G06T15/503

摘要： Systems and methods for discontinuity edge overdraw are described. In one aspect, a polygonal mesh is rendered to produce a computer-generated image. The image exhibits aliasing at its discontinuity edges. The discontinuity edges are sorted prior to overdrawing. The discontinuity edges are overdrawn as anti-aliased lines to reduce the aliasing.

摘要翻译： 描述了不连续边缘覆盖的系统和方法。 在一个方面，渲染多边形网格以产生计算机生成的图像。 图像在其不连续边缘处显示出混叠。 不连续边缘在过度抽取之前进行排序。 不连续边缘作为抗锯齿线被透支，以减少混叠。

公开(公告)号：US20050088440A1

公开(公告)日：2005-04-28

申请号：US10692361

申请日：2003-10-22

申请人： Peter-Pike Sloan ,  John Snyder

发明人： Peter-Pike Sloan ,  John Snyder

IPC分类号： G06T15/50

CPC分类号： G06T15/55

摘要： A hardware-accelerated process of computing radiance transfer coefficients (such as for use in image rendering based on precomputed radiance transfer (PRT) techniques) is re-ordered as compared to previously known PRT precomputations to iterate over a sampling of directions about an object. The hardware-accelerated process uses a set of textures representing positions and normals for a sampling of points over a modeled object. In iterating over the directions, the process computes the depth of the object in a shadow buffer, then computes a texture of the radiance contribution based on the normal and position textures and depth from the shadow buffer. The resulting radiance contribution textures of the iterated directions are accumulated to produce a texture representing the radiance transfer coefficients of the sampled positions. This enables the process to avoid reduction operations, ray tracing and slow read-back path limitations of graphical processing units.

摘要翻译： 与之前已知的PRT预计算相比，计算辐射传输系数（例如用于基于预计算辐射传输（PRT）技术的图像渲染中）的硬件加速过程被重新排序以迭代关于对象的方向的采样。 硬件加速过程使用一组表示位置和法线的纹理，用于对建模对象上的点进行抽样。 在迭代方向上，过程计算阴影缓冲区中对象的深度，然后根据阴影缓冲区的法线和位置纹理以及深度计算辐射贡献的纹理。 累积迭代方向的所得辐射贡献纹理以产生表示采样位置的辐射传递系数的纹理。 这使得该过程能够避免图形处理单元的缩小操作，光线跟踪和慢回读路径限制。

公开(公告)号：US20050035973A1

公开(公告)日：2005-02-17

申请号：US10945827

申请日：2004-09-21

申请人： John Snyder ,  John Whitted ,  William Blank ,  Kirk Olynyk

发明人： John Snyder ,  John Whitted ,  William Blank ,  Kirk Olynyk

IPC分类号： G06T15/20 ,  G06T15/50 ,  G09G5/00

CPC分类号： G06T15/80 ,  G06T15/04

摘要： Systems and methods are provided for variable source rate sampling in connection with image rendering, which accumulate and resolve over all samples forward mapped to each pixel bin. In accordance with the invention, the textured surface to be rendered is sampled, or oversampled, at a variable rate that reflects variations in frequency among different regions, taking into account any transformation that will be applied to the surface prior to rendering and the view parameters of the display device, thus ensuring that each bin of the rendering process receives at least a predetermined minimum number of samples. In one embodiment, the sampling rate is variably set such that each bin is assured to have at least one sample point. In another embodiment, a tiling approach to division of the surface is utilized. In accordance with the architecture provided, the sample points of the surface are forward mapped to sample squares, other regions, of a rendering device, taking into account any transformations applied to the surface and the view parameters of the rendering device, such that each bin receives at least the predetermined minimum number of samples. A filter determines the value(s) to assign to each pixel based upon accumulation and resolution of all of the sample points that fall within the pixel bin(s), rather than assigning a value by selecting only the point sample that corresponds to the center of the pixel. Gaps or holes left by conventional forward-mapping techniques are eliminated by oversampling the source(s), and interpolated points are generated at a higher rate than the original source signal(s) to adequately cover the destination bins. A pixel, or sub-pixel, binning approach is used that accumulates and resolves over all samples, and performs particularly well compared to prior architectures in areas that have higher frequency content, solving the minification antialiasing problem and producing a high quality result. Anisotropic filtering is handled simply with the forward mapping approach by filtering over all samples that naturally accumulate after the forward map, and via variable control of the number of samples forward mapped to the bins. A variety of image processing applications are contemplated wherein variable rate source sampling, and accumulation and resolution of forward mapped point samples can be applied, ranging from 3-D graphics applications to applications wherein images recorded in a recording/storage environment are mapped to the arbitrary requirements of a display environment.

公开(公告)号：US06266064B1

公开(公告)日：2001-07-24

申请号：US09086965

申请日：1998-05-29

申请人： John Snyder

发明人： John Snyder

IPC分类号： G06T1540

CPC分类号： G06T15/40 ,  G06T15/06 ,  Y10S345/953 ,  Y10S345/958

摘要： A visibility sorting method coherently computes a visibility ordering of a collection of moving objects seen by a moving camera in an animated graphics scene. The method detects whether an object occludes other objects. Objects that form an occlusion cycle are grouped together in the ordering. Objects are represented using convex polyhedra to facilitate occlusion testing. A fast occlusion test determines whether the spatial and angular extents of the convex polyhedra overlap. An exact occlusion test detects collisions between convex polyhedra and the silhouettes of the convex polyhedra.

摘要翻译： 可见度排序方法相互计算动画图形场景中移动相机所看到的移动物体集合的可见性排序。 该方法检测对象是否封闭其他对象。 形成闭塞循环的物体在排序中分组在一起。 使用凸多面体表示对象以便于闭塞测试。 快速闭塞测试确定凸多面体的空间和角度范围是否重叠。 精确的遮挡测试检测凸多面体与凸多面体的轮廓之间的碰撞。

公开(公告)号：US5863828A

公开(公告)日：1999-01-26

申请号：US719475

申请日：1996-09-25

申请人： John Snyder

发明人： John Snyder

IPC分类号： H01L21/762 ,  H01L21/76

CPC分类号： H01L21/76229

摘要： Disclosed are methods for planarizing a pattern of trenches and pillars on a substrate. The trenches are filled by depositing a filler material to a thickness greater than or equal to their depth. Photoresist is then patterned to open at least some areas overlying at least some of the pillars. Exposed resist and filler are then etched isotropically simultaneously to substantially planarize the pattern. In one embodiment, the ratio of resist etch rate to filler etch rate is greater than 1.0. In another embodiment, planarization may be achieved by etching filler material in nonactive areas without exposing caps of capped pillars, e.g., etching with endpoint detection. Then, caps of the capped pillars may then be exposed. These methods may be used in conjunction with chemical mechanical polishing steps with reduced pattern sensitivity, avoiding dishing and isolated pillar erosion.

摘要翻译： 公开了用于平坦化衬底上的沟槽和柱的图案的方法。 通过将填充材料沉积到大于或等于其深度的厚度来填充沟槽。 然后将光致抗蚀剂图案化以打开至少一些覆盖至少一些柱的区域。 然后同时蚀刻暴露的抗蚀剂和填料以基本上平坦化图案。 在一个实施例中，抗蚀剂蚀刻速率与填料蚀刻速率的比率大于1.0。 在另一个实施方案中，可以通过在非活性区域中蚀刻填充材料而不暴露封盖柱的盖，例如用端点检测进行蚀刻来实现平坦化。 然后，盖子的柱子可能会被暴露。 这些方法可以与化学机械抛光步骤结合使用，具有降低的图案灵敏度，避免凹陷和孤立的柱冲蚀。