Search

A deep dive into the technology and art behind cyberspace and braindances in Cyberpunk 2077. Braindances are the recorded memories and feelings of individuals, reprojected in the mind of the viewer. To bring this concept into reality, we decided to follow an unconventional approach to rendering environments and characters in real-time. The core visual concept was based around sparse point clouds and glitch effects. Post processes like datamoshing were used to further hide the underlying geometry, aiming for a surreal, out-of-body experience.

In this paper, we describe the design, development and preliminary evaluation of a novel animation tool for smartphones and tablets, with the goal of improving creativity and problem-solving ability among novice users, mainly young children. The user first draws the objects with markers and crayons on paper and takes a photo with their mobile or tablet to import their drawings into the app as game sprites. They then design their animation scene and point to a part of the character and selecting its animation type from existing buttons. Hence the selected part is animated in a vertex shader while ensuring a smooth transition with the non-pointed part. The results of a preliminary evaluation showed that young children enjoyed interacting with our tool and would recommend it to their friends. Keywords and Phrases: Creativity; video games; visual animation; ease of use.

Кваліфікаційна робота включає пояснювальну записку (50 с., 29 рис., 3 табл., 2 додатки) Метою дипломного проєкту є створення апаратно-прискоренного алгоритму рендерингу 3D-моделей на основі трасування променів. Під час розробки були виконані наступні задачі: • Аналіз існуючих рішень, які дозволяють виконувати рендеринг за допомогою метода трасування променів. • Вибір оптимальних технологій для розробки. • Реалізація спроектованого алгоритму. • Тестування якості рендерингу розробленого алгоритму. • Тестування ефективності алгоритму. • Вибір оптимальних опцій рендерингу. Програма була розроблена з використанням мови С++. Для роботи з графікою була обрана бібліотека GLEW. Для створення головного вікна та зчитування вводу користувача з клавіатури та миші була застосована бібліотека GLFW. Для реалізації графічного інтерфейсу було використано бібліотеку ImGui. Для роботи з математичними обчисленями була інтегрована бібліотека GLM. Qualification work includes an explanatory note (50 pages, 29 figures, 3 tables, 2 appendices) The purpose of the diploma project is to create a hardware-accelerated algorithm for rendering 3D models based on ray tracing. The following tasks were performed during the development: • Analysis of existing solutions that allow rendering using the method of ray tracing. • Selection of optimal technologies for development. • Implementation of the designed algorithm. • Testing the quality of rendering the developed algorithm. • Testing the effectiveness of the algorithm. • Selection of optimal rendering options. The program was developed using the C ++ language. The GLEW library was chosen to work with graphics. The GLFW library was used to create the main window and read user input from the keyboard and mouse. The ImGui library was used to implement the graphical interface. The GLM library was integrated to work with mathematical calculations.

With the increasing volume of 3D applications using immersive technologies such as virtual, augmented and mixed reality, it is very interesting to create better ways to integrate unstructured 3D data such as point clouds as a source of data. Indeed, this can lead to an efficient workflow from 3D capture to 3D immersive environment creation without the need to derive 3D model, and lengthy optimization pipelines. In this paper, the main focus is on the direct classification and integration of massive 3D point clouds in a virtual reality (VR) environment. The emphasis is put on leveraging open-source frameworks for an easy replication of the findings. First, we develop a semi-automatic segmentation approach to provide semantic descriptors (mainly classes) to groups of points. We then build an octree data structure leveraged through out-of-core algorithms to load in real time and continuously only the points that are in the VR user's field of view. Then, we provide an open-source solution using Unity with a user interface for VR point cloud interaction and visualisation. Finally, we provide a full semantic VR data integration enhanced through developed shaders for future spatio-semantic queries. We tested our approach on several datasets of which a point cloud composed of 2.3 billion points, representing the heritage site of the castle of Jehay (Belgium). The results underline the efficiency and performance of the solution for visualizing classifieds massive point clouds in virtual environments with more than 100 frame per second.

In this paper, we propose an active real-time capable 3D graph based simultaneous localization and mapping (Graph SLAM) approach, which actively estimates the state of an autonomous spacecraft relative to a simultaneously established map estimate. The graph is constructed in a tightly-coupled fashion, where an Extended Kalman Filter estimates the relative offset between two of its vertices. An additional relative measurement is derived by matching point clouds obtained by a light detection and ranging (LiDAR) system. In order to yield a significant speed-up, scan matching is implemented on the GPU. To reduce the uncertainty of either the state or the map estimate, we present an approach to actively control the system resting on an extended representation of uncertainty in the map. Furthermore, it adapts its behavior depending on the current uncertainty distribution in order to find a dynamic trade-off between exploitation (improve localization performance) and exploration (improve knowledge about the environment). Finally, we present a post-processing approach to discover landing sites in the map estimate without prior knowledge. The evaluation is conducted in a numerical simulation, where the spacecraft explores the real 3D model of Itokawa in its actual dynamic environment. Within that simulation, we use a shader-based GPU implementation for simulating LiDAR measurements. We evaluate the performance of the active SLAM approach and demonstrate that the use of the adaptive approach improves navigation and exploration performance at the same time.

The shader system for a modern game engine comprises much more than just compilation of source code to executable kernels. Shaders must also be exposed to art tools, interfaced with engine code, and specialized for performance. Engines typically address each of these tasks in an ad hoc fashion, without a unifying abstraction. The alternative of developing a more powerful compiler framework is prohibitive for most engines. In this paper, we identify staged metaprogramming as a unifying abstraction and implementation strategy to develop a powerful shader system with modest effort. By using a multi-stage language to perform metaprogramming at compile time, engine-specific code can consume, analyze, transform, and generate shader code that will execute at runtime. Staged metaprogramming reduces the effort required to implement a shader system that provides earlier error detection, avoids repeat declarations of shader parameters, and explores opportunities to improve performance. To demonstrate the value of this approach, we design and implement a shader system, called Selos, built using staged metaprogramming. In our system, shader and application code are written in the same language and can share types and functions. We implement a design space exploration framework for Selos that investigates static versus dynamic composition of shader features, exploring the impact of shader specialization in a deferred renderer. Staged metaprogramming allows Selos to provide compelling features with a simple implementation.

Shader lamp systems augment the real environment by projecting new textures on known target geometries. In dynamic scenes, object tracking maintains the illusion if the physical and virtual objects are well aligned. However, traditional trackers based on texture or contour information are often distracted by the projected content and tend to fail. In this paper, we present a model-based tracking strategy, which directly takes advantage from the projected content for pose estimation in a projector-camera system. An iterative pose estimation algorithm captures and exploits visible distortions caused by object movements. In a closed-loop, the corrected pose allows the update of the projection for the subsequent frame. Synthetic frames simulating the projection on the model are rendered and an optical flow-based method minimizes the difference between edges of the rendered and the camera image. Since the thresholds automatically adapt to the synthetic image, a complicated radiometric calibration can be avoided. The pixel-wise linear optimization is designed to be easily implemented on the GPU. Our approach can be combined with a regular contour-based tracker and is transferable to other problems, like the estimation of the extrinsic pose between projector and camera. We evaluate our procedure with real and synthetic images and obtain very precise registration results.

We built a ‘virtual-world’ of real seabed for the visual analysis. Sub-bottom profile is imported in the 3D environment.” section-drilling” three-dimensional model is designed according to the characteristics of the multi-source comprehensive data under the seabed. In this model, the seabed stratigraphic profile obtained by seismic reflection is digitized into discrete points and interpolated with an approved Krig- ing arithmetic to produce uniform grid in every strata layer. The Delaunay triangular model is then constructed in every layer and calibrated using the drilling data to rec- tify the depth value of the dataset within the buffer. Finally, the constructed 3D seabed stratigraphic model is rendered in every layer by GPU shader engine. Based on this model, two state-of-the-art applications on website explorer and smartphone prove its ubiquitous feature. The resulting ‘3D Seabed’ is used for simulation, visualization, and analysis, by a set of interlinked, real-time layers of information about the 3D Seabed and its analysis result.

Monte-Carlo Renderers must generate many color samples to produce a noise-free image, and for each of those, they must evaluate complex mathematical models representing the appearance of the objects in the scene. These models are usually in the form of shaders: Small programs that are executed during rendering in order to compute a value for the current sample. Renderers often compile and optimize shaders just before rendering, taking advantage of the knowledge of the scene. In principle, the entire renderer could benefit from a-priori code generation. For instance, scheduling can take advantage of the knowledge of the scene in order to maximize hardware usage. However, writing such a configurable renderer eventually means writing a compiler that translates a scene description into machine code. In this paper, we present a framework that allows generating entire renderers for CPUs and GPUs without having to write a dedicated compiler: First, we provide a rendering library in a functional/imperative language that elegantly abstracts the individual rendering concepts using higher-order functions. Second, we use partial evaluation to combine and specialize the individual components of a renderer according to a particular scene. Our results show that the renderers we generate outperform equivalent high-performance implementations written with state-of-the-art ray tracing libraries on the CPU and GPU.

Background Precise definition, rendering and manipulation of visual stimuli are essential in neuroscience. Rather than implementing these tasks from scratch, scientists benefit greatly from using reusable software routines from freely available toolboxes. Existing toolboxes work well when the operating system and hardware are painstakingly optimized, but may be less suited to applications that require multi-tasking (for example, closed-loop systems that involve real-time acquisition and processing of signals). New method We introduce a new cross-platform visual stimulus toolbox called Shady ( https://pypi.org/project/Shady )—so called because of its heavy reliance on a shader program to perform parallel pixel processing on a computer's graphics processor. It was designed with an emphasis on performance robustness in multi-tasking applications under unforgiving conditions. For optimal timing performance, the CPU drawing management commands are carried out by a compiled binary engine. For configuring stimuli and controlling their changes over time, Shady provides a programmer's interface in Python, a powerful, accessible and widely-used high-level programming language. Results Our timing benchmark results illustrate that Shady's hybrid compiled/interpreted architecture requires less time to complete drawing operations, exhibits smaller variability in frame-to-frame timing, and hence drops fewer frames, than pure-Python solutions under matched conditions of resource contention. This performance gain comes despite an expansion of functionality (e.g. “noisy-bit” dithering as standard on all pixels and all frames, to enhance effective dynamic range) relative to previous offerings. Conclusions Shady simultaneously advances the functionality and performance available to scientists for rendering visual stimuli and manipulating them in real time.

This paper presents current work undertaken by the British Broadcasting Corp. (BBC) to look at the representation of human skin tones in International Telecommunication Union-Radiocommunication (ITU-R) Recommendation BT.2100 high dynamic range video systems. Specifically, the author presents luma values for a range of skin tones, categorized by the Fitzpatrick scale, which can be used as a lineup guide by cameramen, racks/shader operators, and colorists. The effect of makeup is also covered.

A combined method of object visualization based on analytical and scalar perturbation functions and three-dimensional textures with the use of graphics processing units is proposed. To display the terrain and the change in levels of detail, the same method as that for color textures is applied, and vertex shaders are used in the case of scattered light. A method of real-time visualization of volumetric clouds is described. For this purpose, it is proposed to form three-dimensional textures by means of pre-processing of the cloud structure and volume-oriented visualization.

The traditional 2D panoramic view has the problem of small imaging range, low utilization of original image and serious stretching of the foreground. This paper designs a 3D panoramic viewing system. The real-time performance of the panoramic system requires a large number of parallel image transformations. The general-purpose processor CPU is incapable. This paper designs an embedded GPU solution. The core computing module is based on NXP's i.MX6Q application processor and builds an embedded Linux system. Using V4L2 to capture images to reduce memory and CPU usage, and use OpenGL ES shaders to process image transformations in parallel at high speed. Because it is in a 3D environment, it is impossible to cover all images through a still viewpoint like a 2D look-around. In order to roam the 3D scene, this paper proposes to design a virtual camera system. Using the virtual camera to roam the 3D environment, realize the virtual viewpoint in the 3D scene, traverse each scene in the grid, eliminate the dead angle of the field of view, and finally realize the 3D panoramic view, and verified on the embedded hardware platform, which can clearly roam every image on the surface. And recorded the video of 3-D looping. Experiments show that the 3D panoramic viewing system proposed in this paper has excellent performance and good effects. It has a good real-time performance on the image display, and the response speed is increased by 5%. The main operation is undertaken by the GPU and only takes a small number of CPU resources. The proposed virtual camera system can better realize the 3D panoramic view.

The power consumption models of mobile application processors have emerged as key objects of interest following the tremendous growth in mobile device production given that such consumption is an important factor in the graphics performance of mobile technologies. Conventionally, the performance of the graphics processing units (GPUs) depends critically on texture mapping units, which is why the number of such GPU components and texture fill rates value prominently whenever the GPU performance is evaluated. Our previous work has established a model to predict maximum performance based on unified shaders. By extending the work, this paper developed a practically applicable GPU performance prediction model on the basis of texture mapping performance. The effects of increased texture mapping units on unified shader performance and GPU efficiency were examined, and a performance prediction model based on the number of frames per second (FPS) was constructed. For these purposes, a benchmark related to texture mapping units was formulated and the experiments were conducted to determine utilization factors that are relevant to GPU performance and efficiency. The final stage in model construction involved establishing a relationship between the previously investigated utilization factors and relevant resources that are consumed during graphics processing. The experimental results showed that the proposed prediction model produced an average error rate of 5.77%.

The visualization toolkit (VTK) is a popular cross-platform, open source toolkit for scientific and medical data visualization, processing, and analysis. It supports a wide variety of data formats, algorithms, and rendering techniques for both polygonal and volumetric data. In particular, VTK's volume rendering module has long provided a comprehensive set of features such as plane clipping, color and opacity transfer functions, lighting, and other controls needed for visualization. However, due to VTK's legacy OpenGL backend and its reliance on a deprecated API, the system did not take advantage of the latest improvements in graphics hardware or the flexibility of a programmable pipeline. Additionally, this dependence on an antiquated pipeline posed restrictions when running on emerging computing platforms, thereby limiting its overall applicability. In response to these shortcomings, the VTK community developed a new and improved volume rendering module, which not only provides a modern graphics processing unit-based implementation, but also augments its capabilities with new features such as fast volume clipping, gradient-magnitude-based opacity modulation, render to texture, and hardware-based volume picking.

En este polimedia se describe el shader Principled GSDF, su uso en blender y algunos de sus parámetros más importantes, Visualización, reproducción y estudio

By analyzing the current situation of "computer graphics" experimental teaching, the results point out that there are deficiencies in guiding students to recognize GPU (Graphics Processing Unit) in the current experimental teaching. Through the construction of GPU rendering architecture cognitive experiments, GPU computing performance cognitive experiments and GPU graphics interface consistency testing experiments, the progressive planning of each part, the introduction of shaders and shading language, the design of typical cases such as particle system and deferred rendering, a complete graphics experiment system oriented to GPU is obtained, which effectively supplements and improves the original course experiment.

Cybersickness is one of the major roadblocks in the widespread adoption of mixed reality devices. Prolonged exposure to these devices, especially virtual reality devices, can cause users to feel discomfort and nausea, spoiling the immersive experience. Incorporating spatial blur in stereoscopic 3D stimuli has shown to reduce cybersickness. In this paper, we develop a technique to incorporate spatial blur in VR systems inspired by the human physiological system. The technique makes use of concepts from foveated imaging and depth-of-field. The developed technique can be applied to any eye tracker equipped VR system as a post-processing step to provide an artifact-free scene. We verify the usefulness of the proposed system by conducting a user study on cybersickness evaluation. We used a custom-built rollercoaster VR environment developed in Unity and an HTC Vive Pro Eye headset to interact with the user. A Simulator Sickness Questionnaire was used to measure the induced sickness while gaze and heart rate data were recorded for quantitative analysis. The experimental analysis highlighted the aptness of our foveated depth-of-field effect in reducing cybersickness in virtual environments by reducing the sickness scores by approximately 66%.

Recently, ray tracing techniques have been highly adopted to produce high quality images and animations. In this paper, we present our design and implementation of a real-time ray-traced rendering engine. We achieved real-time capability for triangle primitives, based on the ray tracing techniques on GPGPU (general-purpose graphics processing unit) compute shaders. To accelerate the ray tracing engine, we used a set of acceleration techniques, including bounding volume hierarchy, its roped representation, joint up-sampling, and bilateral filtering. Our current implementation shows remarkable speed-ups, with acceptable error values. Experimental results shows 2.5–13.6 times acceleration, and less than 3% error values for the 95% confidence range. Our next step will be enhancing bilateral filter behaviors.

When a ray hits a geometry in the scene, the ray tracing hardware needs some way to determine which shader to call to perform intersection tests or shading calculations. The Shader Binding Table (SBT) provides this information. The SBT is a lookup table that associates each geometry in the scene with a set of shader function handles and parameters for these functions. Each set of function handles and parameters is referred to as a shader record. When a geometry is hit by a ray, a set of parameters specified on both the host and device sides of the application combine to determine which shader record is called. The three GPU ray tracing APIs (DirectX Raytracing, Vulkan KHR Ray Tracing, and OptiX) use the SBT to run user code when tracing rays in the scene. These APIs provide a great deal of flexibility as to how the SBT can be set up and indexed during rendering, providing a number of options to applications. However, this generality makes properly setting up the SBT an especially thorny part of these APIs for new users, as incorrect SBT access often leads to crashes or difficult bugs. Translating knowledge from one API to another can also be difficult due to subtle naming differences between them. This chapter looks at the similarities and differences of each API's SBT to develop a holistic understanding of the programming model. A few common configurations of the scene, SBT, and renderer are also discussed to provide guidance through hands-on examples.

With the continuous development and progress of virtual reality technology in recent years, the application of virtual reality technology in all aspects of real life is no longer limited to the military field, medical, or film production fields, but it gradually appears in front of the public, into the lives of ordinary people. The human-computer interaction method in virtual reality and the presentation effect of the virtual scene are the two most important aspects of the virtual reality experience. How to provide a good human-computer interaction method for virtual reality applications and how to improve the final presentation effect of the virtual reality scene is also becoming an important research direction. This paper takes the virtual fitness club experience system as the application background, analyzes the function and performance requirements of the virtual reality experience system in the virtual reality environment, and proposes the use of Kinect as a video acquisition device to extract the user’s somatosensory operation actions through in-depth information to achieve somatosensory control. This article adopts a real human-computer interaction solution, uses Unity 3D game engine to build a virtual reality scene, defines shaders to improve the rendering effect of the scene, and uses Oculus Rift DK2 to complete an immersive 3D scene demonstration. This process greatly reduces resource consumption; it not only enables users to experience unprecedented immersion as users but also helps people create unprecedented scenes and experiences through virtual imagination. The virtual fitness club experience system probably reduces resource consumption by nearly 70%.

The most fundamental step in any ray tracing program is the ray generation (or "raygen") program that produces the rays themselves. This chapter describes seven essential projections that should be in every toolkit and gives parameterized raygen shader code for each.

Aquest projecte consisteix en la creació, disseny i desenvolupament d'un simulador de cossos celestes amb un cert grau de realisme físic en un entorn immersiu de Realitat Virtual. La simulació inclou la vista en detall d'una galàxia i d'un forat negre sense rotació, a mes d'una vista 360 graus des de la terra en la que es poden seleccionar altres cossos celestes sense entrar-hi en detall. La implementació s'ha fet en Unity i amb l'equipament de realitat virtual HTC Vive. This project is about the creation, design and development of a celestial body simulator with a certain degree of physic realism in a Virtual Reality environment. The simulation includes the detailed view of a galaxy and a non-rotating black hole, plus a 360-degree view from the Earth point of view, where we can look at some other celestial bodies with a lot less detail. The project was implemented with Unity and the HTC Vive VR equipment. Este proyecto consiste en la creación, diseño y desarrollo de un simulador de cuerpos celestes con un cierto grado de realismo físico en un entorno inmersivo de Realidad Virtual. La simulación incluye la vista en detalle de una galaxia y de un agujero negro sin rotación, además de una vista 360 grados desde tierra en la que se pueden seleccionar otros cuerpos celestes sin entrar en detalle. La implementación se ha llevado a cabo con el equipamiento de realidad virtual HTC Vive.

International audience; With the increasing use of high-order methods and high-order meshes, scientific visualization software need to adapt themselves to reliably render the associated meshes and numerical solutions. In this paper, a novel approach, based on OpenGL 4 framework, enables a GPU-based rendering of high-order meshes as well as an almost pixel-exact rendering of high-order solutions. Several aspects of the OpenGL Shading Language and in particular the use of dedicated shaders (GPU programs) allows to answer this visualization challenge. Fragment shaders are used to compute the exact solution for each pixel, made possible by the transfer of degrees of freedom and shape functions to the GPU with textures. Tessellation shaders, combined with geometric error estimates, allow us to render high-order curved meshes by providing an adaptive subdivision of elements on the GPU directly. A convenient way to compute bounds for high-order solutions is described. The interest of using Bézier basis instead of Lagrange functions lies in the existence of fast and robust evaluation of polynomial functions with de Casteljau algorithm. A technique to plot highly nonlinear isolines and wire frames with a desired thickness is derived. It is based on a finite difference scheme performed on GPU. In comparison with standard techniques, we remove the use of any linear interpolation step and the need to generate a priori a fixed subdivided mesh. This reduces the memory footprint, improves the accuracy and the speed of the rendering. Finally, the method is illustrated with various 3D examples.

Ray cones were presented as a fast, approximate way to calculate a suitable mip level index for a particular texture sample in a ray tracing shader setup. Though the original technique was doing all the mathematics needed to compute the final mip level index, in this chapter we reformulate the problem in a different way that relies on existing hardware-supported instructions. This maintains almost the same visual results and leads to more convenient shader code. It also further simplifies and reduces the number of instructions from the original ray cones implementation, though we do not claim this necessarily leads to better performance.

With the recent release of inline ray tracing, it is possible to traverse and register ray hits inside a pixel shader. This allows for convenient implementation of ray tracing into past rasterization algorithms and possibly improve on their limitations. One such rasterization algorithm is image-space refractions, which are used for approximating refractions in real time. Image-space refractions are limited in that they can be highly inaccurate when refracting through concave objects containing more than two surface layers. This chapter combines image-space refractions with inline ray tracing into a hybrid method that overcomes such limitations and generates more realistic refractions. The results are closer to fully ray traced images, but using fewer rays. By replacing some rays with image-space refractions, our hybrid method improves rendering speed as compared to pure ray traced refractions.

Virtual reality (VR) is rapidly becoming more widely available and accessible as a technology due to the affordability of cheap computing power. This has made it possible for virtual reality systems to capture audiences in industry and education, as well as for personal use. Currently, a major limitation of VR headsets is that the user’s vision is completely occluded, making it difficult for them to interact with others. While this can be solved by having a VR headset and VR capable computer for each user, this becomes much more expensive and, often, an unrealistic solution. This becomes even more problematic in an educational setting since it is difficult for the given instructor and large groups of students to have a shared learning experience. Here, we have developed anaglyph 3D functionalities into our Visible Heart® Laboratories’ anatomical virtual reality platform. These functionalities augment what is viewed by the virtual reality user with a custom anaglyph shader which in turn projects it to an external display. This allows a multitude of users to wear anaglyph “red/blue 3D glasses” and view the same anatomies the VR instructor is viewing in VR, while preserving the important 3D anatomical spatial relationships.

This chapter describes how to use intersection and closest-hit shaders to implement real-time visualizations of complex fractals using distance functions. The Mandelbulb and Julia sets are used as examples.

Diffusion-weighted magnetic resonance imaging is a technique aimed at measuring the displacement of water molecules inside biological tissues. From High Angular Resolution Diffusion Imaging acquisitions, it is possible to reconstruct fiber orientation distribution functions (fODF) describing the apparent quantity of white matter fibers going through a voxel for some arbitrary direction. Because these fODF are signals on the sphere, they are usually represented using a spherical harmonics (SH) basis, and visualized as radially scaled spherical glyphs. In this work, we present a novel GPU-based method for interactive real-time visualization of fODF datasets using modern OpenGL. Our algorithm relies on compute shaders to distribute the deformation of SH glyphs on the GPU, allowing real-time slicing of fODF images. We show that our method offers better performance than CPU-based methods and allows the real-time exploration of large datasets.

We build acceleration structures for voxel/brick scenes using NVIDIA OptiX and render them in a non-photorealistic style with outlines and one bounce of indirect lighting; this method runs at interactive rates on recent RTX hardware and is implemented entirely in OptiX shaders with no post-processing.

Real-time physically based rendering has long been looked at as the holy grail in Computer Graphics. With the introduction of Nvidia RTX-enabled GPUs family, light transport simulations under real-time constraint started to look like a reality. This paper presents Lift, an educational framework written in C++ that explores the RTX hardware pipeline by using the low-level Vulkan API and its Ray Tracing extension, recently made available by Khronos Group. Furthermore, to accomplish low variance rendered images, we integrated the AI-based denoiser available from the Nvidia ́s OptiX framework. Lift’s development arose primarily in the context of the graduate 3D Programming course taught at Instituto Superior Técnico and Master Theses focused on Real-Time Ray Trac- ing and provides the foundations for laboratory assignments and projects development. The platform aims to make easier students to learn and to develop, by programming the shaders of the RT pipeline, their physically-based ren- dering approaches and to compare them with the built-in progressive unidirectional and bidirectional path tracers. The GUI allows a user to specify camera settings and navigation speed, to select the input scene as well as the rendering method, to define the number of samples per pixel and the path length as well as to denoise the generated image either every frame or just the final frame. Statistics related with the timings, image resolution and total number of accumulated samples are provided too. Such platform will teach that nowadays physically-accurate images can be rendered in real-time under different lighting conditions and how well a denoiser can reconstruct images rendered with just one sample per pixel.

One goal of the project described in this paper is to create learning algorithms for machines and robots that lack a precise virtual controller for correct simulations. Using a digital twin approach, the developed mixed reality application aims for an overlay of a virtual robot model with the real world counterpart using Microsoft HoloLens 2 smart glasses. The application should help users to have an inside look into the results of the learning algorithm and therefore supervise and improve those results. The main focus of this paper is the visual representation of the digital twin on the smart glasses. One of the challenges is the level of abstraction and specific use of shaders (program code defining material attributes) to help the user differentiating between virtual and real objects. Therefore different presentation methods are described and evaluated. Study results with 48 persons show that the most abstract representation (wireframe) scores lowest, whereas a half-transparent model works best.

This paper presents a technique to incorporate spatial blur effects in virtual reality devices. The considered spatial blur is based on foveation and defocus blur: concepts inspired by the human visual system. The proposed technique can be applied to any head-mounted display as a post-processing step. Our foveated depth-of-field method removes intensity leakage artifacts in the transitory regions and works in real-time. We verify the usefulness of our technique by conducting a pilot study on depth perception in virtual environments. In the conducted user study, systems integrated with our blur effect provided a better estimation of object depth in the peripheral regions.

The TPN-USP Maneuvering Simulation Center is the largest Ship Maneuvering Simulation Center in Brazil. The simulator is used to evaluate new ports and operations, risk analysis, pilots and captains training. The center has 6 cabins, in which of them, 3 are classified as full-mission. The simulation can be executed in single or multiplayer mode. This article gives an overview of graphics technologies in TPN-USP simulator center. Its visualization system aims to immerse the pilot into a realistic virtual environment, providing a high definition visual information to make an operation decision. This article describes some of technologies developed and applied in the simulation center. A full mission simulator with 32 projectors filling 282° of dome screen with 3.6 m height, using 11 render computers cluster is presented. An overview of modeling process, model textures that utilizes PBR (Physically Based Rendering) approach is also presented. This technique generates a photorealistic render. A wave GPU optimized rendering was also integrated. The technique allows to adapt various wave spectrums and spreading effect in modular way. Water spray and foam effects was also included. Additionally, advanced shader methods were used to ensure realistic ocean rendering, including light of sun reflection and sub-surface light scattering.

3D engines for real time CAD geometry representation have been improved extremely in recent years, both, thanks to the evolution of the computer industry itself and the new technologies used for computer graphics, like OpenGL shaders and their implementation in the last graphic cards generation. Raytracing and radiosity rendering techniques are achieving more and more close to reality results thanks to these improvements. Many manufacturing industries are taking advantage of these technologies, like footwear industry, where 3D CAD shoe models are been rendering in real time with a huge qualitative leap in terms of efficiency, costs and close-to-reality visualization results. All the same, the performance of the computational models used for the representation of virtual materials, texture maps (like normal or roughness map), specular and diffuse reflection models, illumination or shadows among many other elements, is leading to having different visualization results depending on the 3D engine that it is been used, even though we work with the same CAD model together with its materials and representation scene. Furthermore, if we bring all these implementations to web technologies, like WebGL, we must tackle not only the visualization problem but also, data optimization and computational capacity issues due to the fact of the web browsers and Internet nature. This paper proposes a computational model for hyper-realistic representation in 3D engines that offers correct results for both, 3D engines optimized for computers and 3D engines for web environments. The proposed model adapts the different characteristics of both environments and makes possible an identical visualization of a 3D CAD shoe model whatever the environment chosen. The authors thank INESCOP and its CAD/CAM development team for their commitment and involvement, and especially Vicente López. This work was also supported by the Spanish Research Agency (AEI) and the European Regional Development Fund (ERDF) under project CloudDriver4Industry TIN2017-89266-R.

We completed the previous chapter with a red rectangle painted into the window of a web browser. The process to make the rectangle included the following steps: setting up data inside a vertex and fragment shader; storing the information in buffers; and commanding the WebGL application to execute its drawing instructions. If these steps make up the state and behavior of a WebGL program that rasterizes 2D content, and every WebGL program is a machine that operates on state, then how can we use what we have already created to add a third dimension to our scene?

In this decade, the way of simulating medical scenarios has evolved considerably, for some years now, this area and virtual reality came together giving life to a much more immersive form of simulation. The great challenge in medical simulation is to achieve a considerable level of realism and performance, as it is limited by the complexity of the scenario and other factors, the hardware factor being the main limiting. Giving the user the possibility to choose between greater or less realism requires that it be defined with which technique it would be achieved, therefore, this research compares three forms of surgical incision simulation for virtual reality: Activation by Sequence, Morph Target Animation and CG/HLSL Programming, evaluating factors such as: frames per-second (fps), CPU and GPU usage, which helped to obtain the level of realism of each technique; resulting in that CG/HLSL Programming uses fewer resources, with 27% CPU usage, 5% integrated GPU, 45% dedicated GPU, 60 fps and 44.3% realism, continuing, with an intermediate level use of resources Activation by Sequence with 11% CPU usage, 18% integrated GPU, 57% dedicated GPU, 60 fps, providing 46.5% realism, finally, the technique that used the most resources and obtained the highest level of realism was Morph Target Animation with 23% CPU usage, 22% integrated GPU, 77% dedicated GPU, 53 fps and 51.3% realism; these techniques can be used depending on the objective of the project where more or less realism is required, considering the use of hardware resources.

Real-time ray-tracing debuted to consumer GPU hardware in 2018. Primary examples however, have been of hybrid raster and ray-tracing methods that are restricted to triangle mesh geometry. Our research looks at the viability of procedural methods in the real-time setting. We give implementations of analytical and implicit geometry in the domain of the global illumination algorithms bi-directional path-tracing, and GPU Photon-Mapping – both of which we have adapted to the new ray-tracing shader stages, as shown in Figure 1. Despite procedural intersections being more expensive than triangle intersections in Nvidia’s RTX hardware, our results show that these descriptions still run at interactive rates within computationally expensive multi-pass ray-traced global illumination and demonstrate the practical benefits of the geometry.

We present a method to add distorted perspective effects for scenes with a forward camera dolly (the camera moves in the depth direction). Our target scene is a first-person view of the main character traversing a long path. A distorted perspective has been applied to such scenes in hand-drawn animation films to create more dynamic and dramatic motions. Unfortunately, it is difficult to create a perspective for the camera direction in 3D animation. Therefore, we created an interactive tool to design cartoon-like perspectives for 3D computer-generated animations. Users can control the affine transformation, including translation, rotation, and scaling, in the depth direction of the camera coordinate system on a 2D screen. We implemented the proposed deformer on a vertex shader to ensure the real-time performance of our system.

Modern ray tracing APIs allow developers to easily build acceleration structures (AS) with various optimization techniques. However, the visibility-driven on-demand build can not be implemented with the current APIs due to the lack of flexibility during ray traversal. In this paper, we propose a new algorithm to lazily build ASes for real-time ray tracing with an extended programming model supporting flexible ray traversal. The core idea of our approach is a multi-pass build-traversal, which computes instance visibility and builds the visible ASes in different passes. This allows us to lazily build the entire AS only when necessary without hardware implication. Applying our algorithm to dynamic scenes, we demonstrate that the build cost is significantly reduced with minimal overhead.

We present a novel real-time face detail reconstruction method capable of recovering high quality geometry on consumer mobile devices. Our system firstly uses a morphable model and semantic segmentation of facial parts to achieve robust self-calibration. We then capture fine-scale surface details using a patch-based Shape from Shading (SfS) approach. We pre-compute the patch-wise constant Moore–Penrose inverse matrix of the resulting linear system to achieve real-time performance. Our method achieves high interactive frame-rates and experiments show that our new approach is capable of reconstructing high-fidelity geometry with corresponding results to off-line techniques. We illustrate this through comparisons with off-line and on-line related works, and include demonstrations of novel face detail shader effects processing.

We present the design and implementation of a ”Laser Graphics Processing Unit” (LGPU) featuring a proposed re-configurable graphics pipeline capable of minimal latency interactive feedback, without the need of computer communication. This is a novel approach for creating interactive graphics where a simple program describes the interaction on a vertex. Similar in design to a geometry or fragment shader on a GPU, these programs are uploaded on initialisation and do not require input from any external micro-controller while running. The interaction shader takes input from a light sensor and updates the vertex and fragment shader, an operation that can be parallelised. Once loaded onto our prototype LGPU the pipeline can create laser graphics that react within 4 ms of interaction and can run without input from a computer. The pipeline achieves this low latency by having the interaction shader communicate with the geometry and vertex shaders that are also running on the LGPU. This enables the creation of low latency displays such as car counters, musical instrument interfaces, and non-touch projected widgets or buttons. From our testing we were able to achieve a reaction time of 4 ms and from a range of up to 15 m.

Programmable graphics hardware is growing in capability an d flexibility at a rapid pace. Existing languages for programming this hardware make it difficult at best to bui ld collections of custom graphics algorithms that can be combined as needed. We present a pure functional shadi ng language, Renaissance, that uses the concepts of computational frequency and frequency inference to natu rally allow composition of shader concepts without generating redundant code. We also provide most of the benefi ts of metaprogramming languages without the restriction of requiring a full host environment. I.3.7 [Computer Graphics]: Shading

This paper presents a novel framework that allows low-cost devices to visualize and interact with photorealistic scenes. To accomplish this task, we use the Unity streaming package that allows for streaming an application within its editor and the Unity’s high definition render pipeline that has a proprietary ray-tracing algorithm. The framework contains a realistic scene using a ray tracing algorithm, a virtual reality camera with barrel shaders to correct the lens distortion necessary to use low-cost cardboards, and a method to collect the mobile device’s spatial orientation through a browser to control the user’s vision delivered via WebRTC. The proposed framework can produce low-latency, realistic, immersive environments to be accessed through low-cost HMDs and inexpensive mobile devices.

Many volumetric rendering algorithms use spatial 3D grids as the underlying data structure. Efficient representation, construction, and traversal of these grids are essential to achieve real-time performance, particularly for time-varying data such as in fluid simulations. In this paper, we present improvements on algorithms for building and traversing Bounding Volume Hierarchies (BVH) designed for sparse volumes. Our main insight was to simplify data layout representation by grouping voxels in buckets, preserving their spatiality using Morton codes, instead of using bricks, as current solutions use. Our solution does not use pointers nor stacks, allowing for its usage directly on computing shaders and provides, on average, 9.3x improvement in construction speed, compared with state-of-the-art approaches for Linear Bounding Volume Hierarchies (LBVH).