A Survey Paper on OpenGL ES

In this survey paper introduce the OpenGL (Graphics Library) Es graphics system, which is very useful for embedded system. It means that software interface to graphics hardware. It allows you to create interactive programs that produce color images of moving, three dimensional objects. Using OpenGL, we can control computer graphics technology to produce realistic pictures, or ones that depart from reality in imaginative ways. DOI: 10.17762/ijritcc2321-8169.16040

Accelerated Graphical User Interfaces

Tato práce je zaměřena na multiplatformní grafická uživatelské rozhraní a jejich hardwarovou akceleraci. Popisuje, co to uživatelské rozhraní jsou a srovnává nástroje na jejich tvorbu  a způsoby jejich realizace. Hlavním bodem je vlastní návrh a implementace nástroje na tvorbu multiplatformních hardwarově akcelerovaných grafických uživatelských rozhraní. Srovnává vlastní koncept s existujícími řešeními, a uvádí ho do praxe na projektu s externí firmou.This thesis is focused on a multi-platform graphical user interface and its hardware acceleration. It describes what the user interfaces are, it compares the tools used for their creation, and the methods of their realization. The main focus is a custom design and implementation of tools used for creating a cross-platform hardware accelerated graphical user interface. It compares my own concept with existing solutions, and places it into practice on a project with an external company.

GPU-based Image Analysis on Mobile Devices

With the rapid advances in mobile technology many mobile devices are capable of capturing high quality images and video with their embedded camera. This paper investigates techniques for real-time processing of the resulting images, particularly on-device utilizing a graphical processing unit. Issues and limitations of image processing on mobile devices are discussed, and the performance of graphical processing units on a range of devices measured through a programmable shader implementation of Canny edge detection.Comment: Proceedings of Image and Vision Computing New Zealand 201

XNA-like 3D Graphics Programming on the Raspberry Pi

The Raspberry Pi is a credit-card sized computing device created by Broadcom in 2012. This device is a kind of mini PC, and it is capable of doing things that desktop PC can do. The goal of the Raspberry Pi Foundation is to allow people all over the world to learn programming. Therefore, the Raspberry Pi is designed as a small sized, low cost device that can provide reasonable data processing capability. However, because of its goal is to keep the price down to maximize openness for learning, Raspberry Pi can only run the Linux operating system. XNA is a set of libraries developed by Microsoft to facilitate the creation and management of video games. It provides a large number of underlying functions to help the development of systems that based on runtime. Therefore, programmers may focus on programming their own code. XNA is built on Microsoft's .NET framework, and it is designed to be used with DirectX. However, as no drivers are developed to provide the low level API defined by DirectX on Linux, it is currently impossible to program with XNA on a Raspberry Pi. This thesis investigates the possibility of developing XNA like programs directly on the Raspberry Pi. Instead of using DirectX, OpenGL ES is used to provide the low level graphics APIs. The code of a project named "JBBRXG11", which is an open source project extending XNA classes on Windows to access DirectX 10 and DirectX 11 graphics features is used as a reference for this project. The project successfully built a library that allows an XNA like program to produce moving, textured 3D models on screen

Interactive visualization of a thin disc around a Schwarzschild black hole

In the first course of general relativity, the Schwarzschild spacetime is the most discussed analytic solution to Einstein's field equations. Unfortunately, there is rarely enough time to study the optical consequences of the bending of light for some advanced examples. In this paper, we present how the visual appearance of a thin disc around a Schwarzschild black hole can be determined interactively by means of an analytic solution to the geodesic equation processed on current high performance graphical processing units. This approach can, in principle, be customized for any other thin disc in a spacetime with geodesics given in closed form. The interactive visualization discussed here can be used either in a first course of general relativity for demonstration purposes only or as a thesis for an enthusiastic student in an advanced course with some basic knowledge of OpenGL and a programming language.Comment: 9 pages, 4 figure

Evaluating Tessellation and Screen-Space Ambient Occlusion in WebGL-Based Real-Time Application

abstract: Tessellation and Screen-Space Ambient Occlusion are algorithms which have been widely-used in real-time rendering in the past decade. They aim to enhance the details of the mesh, cast better shadow effects and improve the quality of the rendered images in real time. WebGL is a web-based graphics library derived from OpenGL ES used for rendering in web applications. It is relatively new and has been rapidly evolving, this has resulted in it supporting a subset of rendering features normally supported by desktop applications. In this thesis, the research is focusing on evaluating Curved PN-Triangles tessellation with Screen Space Ambient Occlusion (SSAO), Horizon-Based Ambient Occlusion (HBAO) and Horizon-Based Ambient Occlusion Plus (HBAO+) in WebGL-based real-time application and comparing its performance to desktop based application and to discuss the capabilities, limitations and bottlenecks of WebGL 1.0.Dissertation/ThesisWebGL ProgramOpenGL ProgramMasters Thesis Computer Science 201

Reducing redundancy of real time computer graphics in mobile systems

The goal of this thesis is to propose novel and effective techniques to eliminate redundant computations that waste energy and are performed in real-time computer graphics applications, with special focus on mobile GPU micro-architecture. Improving the energy-efficiency of CPU/GPU systems is not only key to enlarge their battery life, but also allows to increase their performance because, to avoid overheating above thermal limits, SoCs tend to be throttled when the load is high for a large period of time. Prior studies pointed out that the CPU and especially the GPU are the principal energy consumers in the graphics subsystem, being the off-chip main memory accesses and the processors inside the GPU the primary energy consumers of the graphics subsystem. First, we focus on reducing redundant fragment processing computations by means of improving the culling of hidden surfaces. During real-time graphics rendering, objects are processed by the GPU in the order they are submitted by the CPU, and occluded surfaces are often processed even though they will end up not being part of the final image. When the GPU realizes that an object or part of it is not going to be visible, all activity required to compute its color and store it has already been performed. We propose a novel architectural technique for mobile GPUs, Visibility Rendering Order (VRO), which reorders objects front-to-back entirely in hardware to maximize the culling effectiveness of the GPU and minimize overshading, hence reducing execution time and energy consumption. VRO exploits the fact that the objects in graphics animated applications tend to keep its relative depth order across consecutive frames (temporal coherence) to provide the feeling of smooth transition. VRO keeps visibility information of a frame, and uses it to reorder the objects of the following frame. VRO just requires adding a small hardware to capture the visibility information and use it later to guide the rendering of the following frame. Moreover, VRO works in parallel with the graphics pipeline, so negligible performance overheads are incurred. We illustrate the benefits of VRO using various unmodified commercial 3D applications for which VRO achieves 27% speed-up and 14.8% energy reduction on average. Then, we focus on avoiding redundant computations related to CPU Collision Detection (CD). Graphics applications such as 3D games represent a large percentage of downloaded applications for mobile devices and the trend is towards more complex and realistic scenes with accurate 3D physics simulations. CD is one of the most important algorithms in any physics kernel since it identifies the contact points between the objects of a scene and determines when they collide. However, real-time accurate CD is very expensive in terms of energy consumption. We propose Render Based Collision Detection (RBCD), a novel energy-efficient high-fidelity CD scheme that leverages some intermediate results of the rendering pipeline to perform CD, so that redundant tasks are done just once. Comparing RBCD with a conventional CD completely executed in the CPU, we show that its execution time is reduced by almost three orders of magnitude (600x speedup), because most of the CD task of our model comes for free by reusing the image rendering intermediate results. Although not necessarily, such a dramatic time improvement may result in better frames per second if physics simulation stays in the critical path. However, the most important advantage of our technique is the enormous energy savings that result from eliminating a long and costly CPU computation and converting it into a few simple operations executed by a specialized hardware within the GPU. Our results show that the energy consumed by CD is reduced on average by a factor of 448x (i.e., by 99.8\%). These dramatic benefits are accompanied by a higher fidelity CD analysis (i.e., with finer granularity), which improves the quality and realism of the application.El objetivo de esta tesis es proponer técnicas efectivas y originales para eliminar computaciones inútiles que aparecen en aplicaciones gráficas, con especial énfasis en micro-arquitectura de GPUs. Mejorar la eficiencia energética de los sistemas CPU/GPU no es solo clave para alargar la vida de la batería, sino también incrementar su rendimiento. Estudios previos han apuntado que la CPU y especialmente la GPU son los principales consumidores de energía en el sub-sistema gráfico, siendo los accesos a memoria off-chip y los procesadores dentro de la GPU los principales consumidores de energía del sub-sistema gráfico. Primero, nos hemos centrado en reducir computaciones redundantes de la fase de fragment processing mediante la mejora en la eliminación de superficies ocultas. Durante el renderizado de gráficos en tiempo real, los objetos son procesados por la GPU en el orden en el que son enviados por la CPU, y las superficies ocultas son a menudo procesadas incluso si no no acaban formando parte de la imagen final. Cuando la GPU averigua que el objeto o parte de él no es visible, toda la actividad requerida para computar su color y guardarlo ha sido realizada. Proponemos una técnica arquitectónica original para GPUs móviles, Visibility Rendering Order (VRO), la cual reordena los objetos de delante hacia atrás por completo en hardware para maximizar la efectividad del culling de la GPU y así minimizar el overshading, y por lo tanto reducir el tiempo de ejecución y el consumo de energía. VRO explota el hecho de que los objetos de las aplicaciones gráficas animadas tienden a mantener su orden relativo en profundidad a través de frames consecutivos (coherencia temporal) para proveer animaciones con transiciones suaves. Dado que las relaciones de orden en profundidad entre objetos son testeadas en la GPU, VRO introduce costes mínimos en energía. Solo requiere añadir una pequeña unidad hardware para capturar la información de visibilidad. Además, VRO trabaja en paralelo con el pipeline gráfico, por lo que introduce costes insignificantes en tiempo. Ilustramos los beneficios de VRO usango varias aplicaciones 3D comerciales para las cuales VRO consigue un 27% de speed-up y un 14.8% de reducción de energía en media. En segundo lugar, evitamos computaciones redundantes relacionadas con la Detección de Colisiones (CD) en la CPU. Las aplicaciones gráficas animadas como los juegos 3D representan un alto porcentaje de las aplicaciones descargadas en dispositivos móviles y la tendencia es hacia escenas más complejas y realistas con simulaciones físicas 3D precisas. La CD es uno de los algoritmos más importantes entre los kernel de físicas dado que identifica los puntos de contacto entre los objetos de una escena. Sin embargo, una CD en tiempo real y precisa es muy costosa en términos de consumo energético. Proponemos Render Based Collision Detection (RBCD), una técnica energéticamente eficiente y preciso de CD que utiliza resultados intermedios del rendering pipeline para realizar la CD. Comparando RBCD con una CD convencional completamente ejecutada en la CPU, mostramos que el tiempo de ejecución es reducido casi tres órdenes de magnitud (600x speedup), porque la mayoría de la CD de nuestro modelo reusa resultados intermedios del renderizado de la imagen. Aunque no es así necesariamente, esta espectacular en tiempo puede resultar en mejores frames por segundo si la simulación de físicas está en el camino crítico. Sin embargo, la ventaja más importante de nuestra técnica es el enorme ahorro de energía que resulta de eliminar las largas y costosas computaciones en la CPU, sustituyéndolas por unas pocas operaciones ejecutadas en un hardware especializado dentro de la GPU. Nuestros resultados muestran que la energía consumida por la CD es reducidad en media por un factor de 448x. Estos dramáticos beneficios vienen acompañados de una mayor fidelidad en la CD (i.e. con granularidad más fina)Postprint (published version

Towards general purpose computations on low-end mobile GPUs

GPUs traditionally offer high computational capabilities, frequently higher than their CPU counterparts. While high-end mobile GPUs vendors introduced recently general purpose APIs, such as OpenCL, to leverage their computational power, the vast majority of the mobile devices lack such support. Despite that their graphics APIs have similarities with desktop graphics APIs, they have significant differences, which prevent the use of well-known techniques that offer general-purpose computations over such interfaces. In this paper we show how these obstacles can be overcome, in order to achieve general purpose programmability of these devices. As a proof of concept we implemented our proposal on a real embedded platform (Raspberry Pi) based on Broadcom's VideoCore IV GPU, obtaining a speedup of 7.2× over the CPU.This work has been partially supported by the Spanish Ministry of Science and Innovation under grant TIN2015-65316-P and the HiPEAC Network of Excellence. Leonidas Kosmidis is also funded by the Spanish Ministry of Education under the FPU grant AP2010-4208.Postprint (author's final draft