Vector graphics provides powerful tools for drawing scalable 2D imagery. With the rise of mobile computers, of different types of displays and image resolutions, vector graphics is receiving an increasing amount of attention. However, vector graphics is not the leading framework for creating and manipulating 2D imagery. The reason for this reluctance of employing vector graphical frameworks is that it is difficult to handle complex behaviour of colour across the 2D domain. A challenging problem within vector graphics is to define smooth colour functions across the image. In previous work, two approaches exist. The first approach, known as diffusion curves, diffuses colours from a set of input curves and points. The second approach, known as gradient meshes, defines smooth colour functions from control meshes. These two approaches are incompatible: diffusion curves do not support the local behaviour provided by gradient meshes and gradient meshes do not support freeform curves as input. My research aims to narrow the gap between diffusion curves and gradient meshes. With this aim in mind, I propose solutions to create control meshes from freeform curves. I demonstrate that these control meshes can be used to render a vector primitive similar to diffusion curves using subdivision surfaces. With the use of subdivision surfaces, instead of a diffusion process, colour gradients can be locally controlled using colour-gradient curves associated with the input curves. The advantage of local control is further explored in the setting of vector-centric image processing. I demonstrate that a certain contrast enhancement profile, known as the Cornsweet profile, can be modelled via surfaces in images. This approach does not produce saturation artefacts related with previous filter-based methods. Additionally, I demonstrate various approaches to artistic filtering, where the artist locally models given artistic effects. Gradient meshes are restricted to rectangular topology of the control meshes. I argue that this restriction hinders the applicability of the approach and its potential to be used with control meshes extracted from freeform curves. To this end, I propose a mesh-based vector primitive that supports arbitrary manifold topology of the mesh.

Physical simulations of natural phenomena usually boil down to solving an ordinary or partial differential equation system. Partial differential equation systems can be formulated either in differential form or in integral form. This dissertation explores integral methods for the simulation of magnetic fluids, so-called ferrofluids, and the surface of the vast ocean. The first two parts of this dissertation aim to contribute to the development of accurate and efficient methods for simulating ferrofluids on the macroscopic (in the order of millimeters) scale. The magnetic nature of these fluids imposes challenges for the simulation. The two most important challenges are to first model the influence of ferrofluids on surrounding magnetic fields and second the influence of magnetic forces on the fluids’ dynamics. To tackle these challenges, two Lagrangian simulation methods have been proposed. The first method discretizes the magnetic substance as clusters of particles carrying radial basis functions and applies magnetic forces between these particles. This is a mesh-free method suitable for particle-based fluid simulation frameworks such as smoothed-particle hydrodynamics. The second method follows another direction, only discretizing the fluid’s surface as triangles and vertices. A surface-based simulation for the fluid part is employed, and a boundary element method is utilized for the magnetic part. The magnetic forces are added as gradients of the magnetic energy defined on the fluid’s surface. The second approach has to solve significantly fewer unknowns in the underlying equations, and uses a more accurate surface tension model compared to the radial basis function approach. The proposed methods are able to reproduce a series of characteristic phenomena of magnetic fluids, both qualitatively and in some cases even quantitatively which leads to a better understanding of such kind of materials. The boundary element method employed in the second part shows advantages beyond ferrofluids. In the third part of this thesis, a boundary element method is coupled with a particle-based fluid simulator for ocean simulation. The wavy motion of the ocean is simulated using large triangle meshes, while water splashes are simulated using particles. This approach is much more efficient in terms of computation time and memory consumption.

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Shading and texturing are two techniques that flight simulators can take advantage of to increase scene realism. Shading imitates the effects of light reflecting from a surface. Texture refers to superimposing a pattern on a surface to give the illusion of extra detail and realism. In this report, several techniques for shading and texturing are evaluated with respect to their applicability to visual flight simulators. The image quality produced by shading and texturing is a function of computation cost. The Phong model is found to produce the most realistic shading, but is too computationally expensive. The Gouraud shading model improves upon the Phong model in that realistic shading is produced with less computational effort. The table look up technique was found to be the most flexible and realistic way to produce texture on the surface of a polygon. It is shown that true perspective shading is cost effective when texture is required because the hardware needed to produce texturing and true perspective shading are very similar.

The goal of this research is to define and develop a computer graphics display controller that will provide a high performance to cost ratio by employing state-of-the-art components and techniques. This report briefly defines the phrase "computer graphics display system" and the related technologies. The system requirements for a target display controller are developed and their hardware implications are presented. An architectural overview precedes a detailed explanation of all functional areas of the target system. This includes an overview of the VLSI graphic figure generator, which is the heart of the target system. Finally, the concept of hardware independent graphic software is presented.

A computer graphics simulation of an aircraft Head-Up Display was designed using an RDS-3000 Ikonas Graphics Processor and a PDP-11/34 host computer system. The software control and display modules were accomplished using Ikonas microcode and Digital Equipment Corporation Fortran IV-PLUS. The Head-Up Display system consists of the basic flight data, which includes aerodynamic flight information, Roll/Pitch Ladder, and the Velocity Vector or Flight Path Marker. The system was designed for flexibility in modifications and evaluation of various weapons delivery systems. These will be adapted to specific needs by research scientists and engineers at the Visual Technology Research Simulator in Orlando, Florida.