A hybrid representation for modeling, interactive editing, and real-time visualization of terrains with volumetric features

Cataloged from PDF version of article.Terrain rendering is a crucial part of many real-time applications. The easiest way to process and visualize terrain data in real time is to constrain the terrain model in several ways. This decreases the amount of data to be processed and the amount of processing power needed, but at the cost of expressivity and the ability to create complex terrains. The most popular terrain representation is a regular 2D grid, where the vertices are displaced in a third dimension by a displacement map, called a heightmap. This is the simplest way to represent terrain, and although it allows fast processing, it cannot model terrains with volumetric features. Volumetric approaches sample the 3D space by subdividing it into a 3D grid and represent the terrain as occupied voxels. They can represent volumetric features but they require computationally intensive algorithms for rendering, and their memory requirements are high. We propose a novel representation that combines the voxel and heightmap approaches, and is expressive enough to allow creating terrains with caves, overhangs, cliffs, and arches, and efficient enough to allow terrain editing, deformations, and rendering in real time

Virtual tour

Interactive 3D Visualization of Architectural models might be the best way to get some idea about an Architecture Plan. Photo-realistic visualization often attracts the investors and customers for whom the architectural blueprints are obscure. Architectural Visualization is considered to have a bright future ahead of it as more and more architects and real estate developers are using this technology. Virtual Walk-through can give not only ideas about your building but its interiors and design too. The Architectural Virtual Environment also most widely used in Gaming and Entertainment Industry in creating a complex movie scenes or a game environment

Efficient Many-Light Rendering of Scenes with Participating Media

We present several approaches based on virtual lights that aim at capturing the light transport without compromising quality, and while preserving the elegance and efficiency of many-light rendering. By reformulating the integration scheme, we obtain two numerically efficient techniques; one tailored specifically for interactive, high-quality lighting on surfaces, and one for handling scenes with participating media

Sparse Volumetric Deformation

Volume rendering is becoming increasingly popular as applications require realistic solid shape representations with seamless texture mapping and accurate filtering. However rendering sparse volumetric data is difficult because of the limited memory and processing capabilities of current hardware. To address these limitations, the volumetric information can be stored at progressive resolutions in the hierarchical branches of a tree structure, and sampled according to the region of interest. This means that only a partial region of the full dataset is processed, and therefore massive volumetric scenes can be rendered efficiently. The problem with this approach is that it currently only supports static scenes. This is because it is difficult to accurately deform massive amounts of volume elements and reconstruct the scene hierarchy in real-time. Another problem is that deformation operations distort the shape where more than one volume element tries to occupy the same location, and similarly gaps occur where deformation stretches the elements further than one discrete location. It is also challenging to efficiently support sophisticated deformations at hierarchical resolutions, such as character skinning or physically based animation. These types of deformation are expensive and require a control structure (for example a cage or skeleton) that maps to a set of features to accelerate the deformation process. The problems with this technique are that the varying volume hierarchy reflects different feature sizes, and manipulating the features at the original resolution is too expensive; therefore the control structure must also hierarchically capture features according to the varying volumetric resolution. This thesis investigates the area of deforming and rendering massive amounts of dynamic volumetric content. The proposed approach efficiently deforms hierarchical volume elements without introducing artifacts and supports both ray casting and rasterization renderers. This enables light transport to be modeled both accurately and efficiently with applications in the fields of real-time rendering and computer animation. Sophisticated volumetric deformation, including character animation, is also supported in real-time. This is achieved by automatically generating a control skeleton which is mapped to the varying feature resolution of the volume hierarchy. The output deformations are demonstrated in massive dynamic volumetric scenes

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

Rendering Curved Triangles on the GPU

This Thesis presents a new approach to render triangular Bézier patches in real time. The goal is to achieve a very good visual quality, avoid artifacts in the silhouette, and get in nite detail. Our approach consists in a ray casting technique to render tri- angular B ezier patches in real time. It is based on previous work explained in this document to implement a fast ray-surface intersec- tion technique. This previous work consists in adapting Newton's method to implement the intersections achieving interactive framer- ates ray casting di erent surfaces. The main contributions of our approach are adapting New- ton's method to perform intersections with triangular bicubic B ezier patches and implementing it in GPU to optimize performance using graphics hardware. Finally, we also contribute adapting the normal mapping tech- nique to shade the models and, thus, achieve even greater detail