Efficient Hair Rendering with a GPU Cone Tracing Approach

2017 ◽  
Vol 8 (1) ◽  
pp. 1-19
Author(s):  
Jorge R. Martins ◽  
Vasco S. Costa ◽  
João M. Pereira
Keyword(s):  
Human Hair ◽  
State Of The Art ◽  
Sampling Rate ◽  
Current State ◽  
Bounding Volume ◽  
Bounding Boxes ◽  
Bounding Volume Hierarchies ◽  
Bounding Volume Hierarchy

Rendering human hair can be a hard task because of the required high super-sampling rate to render thin hair fibers without noticeable aliasing. Additionally, the current state-of-the-art bounding volume hierarchies (BVHs) are not suitable to hair rendering. In fact, the axis-aligned bounding boxes (AABBs) do not tightly bind hair primitives which impacts negatively the intersection tests activity. Both limitations can degrade severely the rendering performance so described in this article, a cone tracing GPU approach coupled with a hybrid bounding volume hierarchy to tackle these problems. The hybrid BVH makes use of both oriented and axis aligned bounding boxes. It is shown that the experiment is able to drastically reduce the super-sampling required to produce aliasing free images while minimizing the number of intersection tests and achieving speedups of up to 4, depending on the scene.

Hardware-Accelerated Dual-Split Trees

2020 ◽  
Vol 3 (2) ◽  
pp. 1-21
Author(s):  
Daqi Lin ◽  
Elena Vasiou ◽  
Cem Yuksel ◽  
Daniel Kopta ◽  
Erik Brunvand
Keyword(s):  
Ray Tracing ◽  
Hardware Acceleration ◽  
Memory Storage ◽  
Compact Representation ◽  
Space Partitioning ◽  
Data Movement ◽  
Bounding Volume ◽  
Bounding Boxes ◽  
Split Trees ◽  
Bounding Volume Hierarchies

Bounding volume hierarchies (BVH) are the most widely used acceleration structures for ray tracing due to their high construction and traversal performance. However, the bounding planes shared between parent and children bounding boxes is an inherent storage redundancy that limits further improvement in performance due to the memory cost of reading these redundant planes. Dual-split trees can create identical space partitioning as BVHs, but in a compact form using less memory by eliminating the redundancies of the BVH structure representation. This reduction in memory storage and data movement translates to faster ray traversal and better energy efficiency. Yet, the performance benefits of dual-split trees are undermined by the processing required to extract the necessary information from their compact representation. This involves bit manipulations and branching instructions which are inefficient in software. We introduce hardware acceleration for dual-split trees and show that the performance advantages over BVHs are emphasized in a hardware ray tracing context that can take advantage of such acceleration. We provide details on how the operations needed for decoding dual-split tree nodes can be implemented in hardware and present experiments in a number of scenes with different sizes using path tracing. In our experiments, we have observed up to 31% reduction in render time and 38% energy saving using dual-split trees as compared to binary BVHs representing identical space partitioning.

scholarly journals Exploring the Benefits of Depth Information in Object Pixel Masking (Student Abstract)

2020 ◽  
Vol 34 (10) ◽  
pp. 13833-13834
Author(s):  
Anish Kachinthaya ◽  
Yi Ding ◽  
Tobias Hollerer
Keyword(s):  
State Of The Art ◽  
Depth Information ◽  
Spatial Awareness ◽  
Multiple Objects ◽  
Depth Data ◽  
Current State ◽  
Complex Scenes ◽  
Bounding Boxes

In this paper, we look at how depth data can benefit existing object masking methods applied in occluded scenes. Masking the pixel locations of objects within scenes helps computers get a spatial awareness of where objects are within images. The current state-of-the-art algorithm for masking objects in images is Mask R-CNN, which builds on the Faster R-CNN network to mask object pixels rather than just detecting their bounding boxes. This paper examines the weaknesses Mask R-CNN has in masking people when they are occluded in a frame. It then looks at how depth data gathered from an RGB-D sensor can be used. We provide a case study to show how simply applying thresholding methods on the depth information can aid in distinguishing occluded persons. The intention of our research is to examine how features from depth data can benefit object pixel masking methods in an explainable manner, especially in complex scenes with multiple objects.

scholarly journals Dynamic Garment Simulation based on Hybrid Bounding Volume Hierarchy

2016 ◽  
Vol 16 (4) ◽  
pp. 241-249 ◽  
Author(s):  
Dongyong Zhu ◽  
Zhong Li ◽  
Feng Xia ◽  
Yong Xu
Keyword(s):  
Human Body ◽  
Least Squares Method ◽  
Elliptic Cylinder ◽  
Human Body Model ◽  
Mass Model ◽  
Bounding Box ◽  
Bounding Volume ◽  
Simulation Based ◽  
Bounding Boxes ◽  
Bounding Volume Hierarchy

Abstract In order to solve the computing speed and efficiency problem of existing dynamic clothing simulation, this paper presents a dynamic garment simulation based on a hybrid bounding volume hierarchy. It firstly uses MCASG graph theory to do the primary segmentation for a given three-dimensional human body model. And then it applies K-means cluster to do the secondary segmentation to collect the human body’s upper arms, lower arms, upper legs, lower legs, trunk, hip and woman’s chest as the elementary units of dynamic clothing simulation. According to different shapes of these elementary units, it chooses the closest and most efficient hybrid bounding box to specify these units, such as cylinder bounding box and elliptic cylinder bounding box. During the process of constructing these bounding boxes, it uses the least squares method and slices of the human body to get the related parameters. This approach makes it possible to use the least amount of bounding boxes to create close collision detection regions for the appearance of the human body. A spring-mass model based on a triangular mesh of the clothing model is finally constructed for dynamic simulation. The simulation result shows the feasibility and superiority of the method described.

Using Hardware Ray Transforms to Accelerate Ray/Primitive Intersections for Long, Thin Primitive Types

2020 ◽  
Vol 3 (2) ◽  
pp. 1-16
Author(s):  
Ingo Wald ◽  
Nate Morrical ◽  
Stefan Zellmann ◽  
Lei Ma ◽  
Will Usher ◽  
...  
Keyword(s):  
Ray Tracing ◽  
Data Sets ◽  
Bounding Box ◽  
Bounding Volume ◽  
Recent Addition ◽  
Bounding Boxes ◽  
Ray Transforms ◽  
Bounding Volume Hierarchies

With the recent addition of hardware ray tracing capabilities, GPUs have become incredibly efficient at ray tracing both triangular geometry, and instances thereof. However, the bounding volume hierarchies that current ray tracing hardware relies on are known to struggle with long, thin primitives like cylinders and curves, because the axis-aligned bounding boxes that these hierarchies rely on cannot tightly bound such primitives. In this paper, we evaluate the use of RTX ray tracing capabilities to accelerate these primitives by tricking the GPU's instancing units into executing a hardware-accelerated oriented bounding box (OBB) rejection test before calling the user's intersection program. We show that this can be done with minimal changes to the intersection programs and demonstrate speedups of up to 5.9× on a variety of data sets.

scholarly journals Attention Fusion for One-Stage Multispectral Pedestrian Detection

Sensors ◽  
2021 ◽  
Vol 21 (12) ◽  
pp. 4184
Author(s):  
Zhiwei Cao ◽  
Huihua Yang ◽  
Juan Zhao ◽  
Shuhong Guo ◽  
Lingqiao Li
Keyword(s):  
Feature Fusion ◽  
State Of The Art ◽  
Pedestrian Detection ◽  
Complementary Information ◽  
Deep Convolutional Neural Networks ◽  
One Stage ◽  
Current State ◽  
Fusion Methods ◽  
Feature Information ◽  
Bounding Boxes

Multispectral pedestrian detection, which consists of a color stream and thermal stream, is essential under conditions of insufficient illumination because the fusion of the two streams can provide complementary information for detecting pedestrians based on deep convolutional neural networks (CNNs). In this paper, we introduced and adapted a simple and efficient one-stage YOLOv4 to replace the current state-of-the-art two-stage fast-RCNN for multispectral pedestrian detection and to directly predict bounding boxes with confidence scores. To further improve the detection performance, we analyzed the existing multispectral fusion methods and proposed a novel multispectral channel feature fusion (MCFF) module for integrating the features from the color and thermal streams according to the illumination conditions. Moreover, several fusion architectures, such as Early Fusion, Halfway Fusion, Late Fusion, and Direct Fusion, were carefully designed based on the MCFF to transfer the feature information from the bottom to the top at different stages. Finally, the experimental results on the KAIST and Utokyo pedestrian benchmarks showed that Halfway Fusion was used to obtain the best performance of all architectures and the MCFF could adapt fused features in the two modalities. The log-average miss rate (MR) for the two modalities with reasonable settings were 4.91% and 23.14%, respectively.

scholarly journals OLBVH: octree linear bounding volume hierarchy for volumetric meshes

2020 ◽  
Vol 36 (10-12) ◽  
pp. 2327-2340 ◽  
Author(s):  
Daniel Ströter ◽  
Johannes S. Mueller-Roemer ◽  
André Stork ◽  
Dieter W. Fellner
Keyword(s):  
Data Structure ◽  
State Of The Art ◽  
Memory Consumption ◽  
Bounding Volumes ◽  
Bounding Volume ◽  
Speed Up ◽  
Slicing Method ◽  
Testing Speed ◽  
Bounding Volume Hierarchy ◽  
Memory Efficient

Abstract We present a novel bounding volume hierarchy for GPU-accelerated direct volume rendering (DVR) as well as volumetric mesh slicing and inside-outside intersection testing. Our novel octree-based data structure is laid out linearly in memory using space filling Morton curves. As our new data structure results in tightly fitting bounding volumes, boundary markers can be associated with nodes in the hierarchy. These markers can be used to speed up all three use cases that we examine. In addition, our data structure is memory-efficient, reducing memory consumption by up to 75%. Tree depth and memory consumption can be controlled using a parameterized heuristic during construction. This allows for significantly shorter construction times compared to the state of the art. For GPU-accelerated DVR, we achieve performance gain of 8.4$$\times $$ × –13$$\times $$ × . For 3D printing, we present an efficient conservative slicing method that results in a 3$$\times $$ × –25$$\times $$ × speedup when using our data structure. Furthermore, we improve volumetric mesh intersection testing speed by 5$$\times $$ × –52$$\times $$ × .

Behavioral Genetics: Concepts for Research and Practice in Language Development and Disorders

1995 ◽  
Vol 38 (5) ◽  
pp. 1126-1142 ◽  
Author(s):  
Jeffrey W. Gilger
Keyword(s):  
Language Development ◽  
Behavioral Genetics ◽  
State Of The Art ◽  
Genetic Research ◽  
Great Promise ◽  
Behavioral Genetic ◽  
Fine Grained ◽  
Future Goals ◽  
Current State ◽  
Research Designs

This paper is an introduction to behavioral genetics for researchers and practioners in language development and disorders. The specific aims are to illustrate some essential concepts and to show how behavioral genetic research can be applied to the language sciences. Past genetic research on language-related traits has tended to focus on simple etiology (i.e., the heritability or familiality of language skills). The current state of the art, however, suggests that great promise lies in addressing more complex questions through behavioral genetic paradigms. In terms of future goals it is suggested that: (a) more behavioral genetic work of all types should be done—including replications and expansions of preliminary studies already in print; (b) work should focus on fine-grained, theory-based phenotypes with research designs that can address complex questions in language development; and (c) work in this area should utilize a variety of samples and methods (e.g., twin and family samples, heritability and segregation analyses, linkage and association tests, etc.).

Schizophrenia Research: Current State of the Art

1976 ◽  
Vol 21 (7) ◽  
pp. 497-498
Author(s):  
STANLEY GRAND
Keyword(s):  
State Of The Art ◽  
Current State

Bounding Volume Hierarchies for Detecting Collision in Urban Simulation

2008 ◽  
Author(s):  
Hamzah Asyrani Sulaiman ◽  
Abdullah Bade ◽  
Daut Daman ◽  
Mohd Shahrizal Sunar
Keyword(s):  
Bounding Volume ◽  
Urban Simulation ◽  
Bounding Volume Hierarchies

Umbral Calculus

10.37236/24 ◽  
2002 ◽  
Vol 1000 ◽  
Author(s):  
A. Di Bucchianico ◽  
D. Loeb
Keyword(s):  
19Th Century ◽  
Finite Differences ◽  
State Of The Art ◽  
Umbral Calculus ◽  
Current State ◽  
Logical Foundation ◽  
Complete Bibliography ◽  
The 19Th Century ◽  
Mathematical Literature

We survey the mathematical literature on umbral calculus (otherwise known as the calculus of finite differences) from its roots in the 19th century (and earlier) as a set of “magic rules” for lowering and raising indices, through its rebirth in the 1970’s as Rota’s school set it on a firm logical foundation using operator methods, to the current state of the art with numerous generalizations and applications. The survey itself is complemented by a fairly complete bibliography (over 500 references) which we expect to update regularly.

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