Comparison of Shadow Methods

Táto práca sa zaoberá porovnávaním techník vrhania tieňov objektov v rámci scény. V teoretickej časti popisuje a porovnáva možné riešenia vrhania tieňa a podrobnejšie postupy metód Shadow Mapping a Shadow Volumes, ktoré patria medzi najpoužívanejšie techniky tieňovania v reálnom čase. Hlavnou časťou je návrh a implementácia týchto dvoch tieňových metód s využitím knižnice OpenGL. V časti merania porovnáva podľa grafov s nameranými hodnotami a na záver zhodnotenie výsledkov.This thesis talks about comparison of shadow casting techniques within a scene. In the theoretical part, it describes and compares possible solutions of shadow casting and more detailed about Shadow Mapping and Shadow Volumes, which are among the most commonly used real-time shadowing techniques. The main part is about design and implementation of these two shadow methods using the OpenGL library. In the measurement part it compares methods based on measured values. The outcome of my measurements can be found in the final part of my thesis.

Fast self-shadowing using occluder textures

A real-time self-shadowing technique is described. State of the art shadowing techniques that utilize modern hardware often require multiple rendering passes and introduce rendering artifacts. Combining separate ideas from earlier techniques which project geometry onto a plane and project imagery onto an object results in a new real-time technique for self-shadowing. This technique allows an artist to construct occluder textures and assign them to shadow planes for a self-shadowed model. Utilizing a graphics processing unit (GPU), a vertex program computes shadowing coordinates in real-time, while a fragment program applies the shading and shadowing in a single rendering pass. The methodology used to create shadow planes and write the vertex and fragment programs is given, as well as the relation to the previous work. This work includes implementing this technique, applying it to a small set of test models, describing the types of models for which the technique is well suited, as well as those for which it is not well suited, and comparing the techniqueâÂÂs performance and image quality to other state of the art shadowing techniques. This technique performs as well as other real-time techniques and can reduce rendering artifacts in certain circumstances

Fast self-shadowing using occluder textures

A real-time self-shadowing technique is described. State of the art shadowing techniques that utilize modern hardware often require multiple rendering passes and introduce rendering artifacts. Combining separate ideas from earlier techniques which project geometry onto a plane and project imagery onto an object results in a new real-time technique for self-shadowing. This technique allows an artist to construct occluder textures and assign them to shadow planes for a self-shadowed model. Utilizing a graphics processing unit (GPU), a vertex program computes shadowing coordinates in real-time, while a fragment program applies the shading and shadowing in a single rendering pass. The methodology used to create shadow planes and write the vertex and fragment programs is given, as well as the relation to the previous work. This work includes implementing this technique, applying it to a small set of test models, describing the types of models for which the technique is well suited, as well as those for which it is not well suited, and comparing the techniqueâÂÂs performance and image quality to other state of the art shadowing techniques. This technique performs as well as other real-time techniques and can reduce rendering artifacts in certain circumstances

Fast self-shadowing using occluder textures

A real-time self-shadowing technique is described. State of the art shadowing techniques that utilize modern hardware often require multiple rendering passes and introduce rendering artifacts. Combining separate ideas from earlier techniques which project geometry onto a plane and project imagery onto an object results in a new real-time technique for self-shadowing. This technique allows an artist to construct occluder textures and assign them to shadow planes for a self-shadowed model. Utilizing a graphics processing unit (GPU), a vertex program computes shadowing coordinates in real-time, while a fragment program applies the shading and shadowing in a single rendering pass. The methodology used to create shadow planes and write the vertex and fragment programs is given, as well as the relation to the previous work. This work includes implementing this technique, applying it to a small set of test models, describing the types of models for which the technique is well suited, as well as those for which it is not well suited, and comparing the techniqueâÂÂs performance and image quality to other state of the art shadowing techniques. This technique performs as well as other real-time techniques and can reduce rendering artifacts in certain circumstances

Capabilities of OpenGL

Import 05/08/2014Z důvodu rychlého vývoje grafických karet je OpenGL, které je dnes považováno za jeden z grafických standardů, nuceno se neustále přizpůsobovat jejich možnostem a tím měnit i svou specifikaci. V této práci jsou zpracována vybraná témata z oblasti vizualizace dat, na kterých jsou demonstrovány možnosti moderního OpenGL verze 4, včetně hlavních novinek této verze. Pro každé jednotlivé téma v této práci je obsažen teoretický úvod s možným doplněním základních informací o OpenGL funkcionalitě, která je využita v praktické ukázce. Praktická ukázka pro každé téma obsahuje jednu nebo více ukázkových aplikací, přičemž jsou popsány hlavní části implementace jedné z nich. Ukázkové aplikace jsou vytvořeny s pomocí programovacích jazyků C++ a GLSL, knihovny OpenGL a dalších potřebných knihoven.The OpenGL which is concerned as one of graphic standards today is forced to constantly adapt to capabilities of graphic cards and change a specification due to rapid development of them. In this thesis are processed chosen themes from the field of data visualization which are used to demonstrate capabilities of modern OpenGL version 4 including the main news of this version. For every single theme in this thesis is contained theoretical introduction with possible addition of basic information about OpenGL functionality which is used in practical demonstration. Practical demonstration contains one or more demonstration applications with description of main parts for one of them. Demonstration applications are created using programming languages C++ and GLSL, library OpenGL and other necessary libraries.460 - Katedra informatikyvýborn

Real-Time Shadowing Techniques

Shadows heighten realism and provide important visual cues about the spatial relationships between objects. But integration of robust shadow shadowing techniques in real-time rendering is not an easy task. In this course on how shadows are incorporated in real-time rendering, attendees learn basic shadowing techniques and more advanced techniques that exploit new features of graphics hardware.The course begins with shadowing techniques using shadow maps. After an introduction to shadow maps and general improvements of this technique (filtering, depth bias, omnidirectional lights, etc.), the first section describes two methods for reducing sampling artifacts: perspective shadow maps and silhouette maps. Both techniques can significantly improve shadow quality, but they require careful implementation. The course continues with extensions of the shadow mapping method that allow soft shadows from linear and area light sources. The second part of the course discusses recent advances in efficient and robust implementation of shadow volumes on graphics hardware and then shows how shadow volumes can be extended to generate accurate soft shadows from area lights. Finally, the course summarizes real-time shadowing from full lighting environments using the technique of precomputed radiance transfer.The course explains the differences among these algorithms and their strengths and weaknesses. Implementation details, often omitted in technical papers, are provided. And throughout the course, the tradeoffs between quality and performance are illustrated for the different techniques