CoVis 3

Bachelorarbeit von Danyel Merkert

Abstract:

The visualisation of information is a broad area of study not uniquely associated with computing. Its origins can be traced back to the earliest attempts at cartography. It is, however, with the development of computing technology that the discipline has flourished. It is not simply that the technology has allowed for more detailed visual representations to be produced, it is equally the case that the wealth of data available and the understanding of its importance have accelerated the demand for its analysis. The range of modern visualisation is huge, including medical imaging, engineering simulations and geographical and meteorological analysis.

Information can come in many forms – the two most common to visualisation are numerical data and functional representation. This thesis investigates visualisation methods for both mathematical functions of two variables and three-dimensional data. In particular I examined techniques as contour plots and surface plots.

Within the bounds of this project OpenGL turned out to be the most powerful tool regarding visualisation of information. Due to the procedural architecture of OpenGL and an ambition to learn the core architecture of Microsoft Windows®, I decided to exclusively implement this project in Win32®, for which I pay particular attention in this dissertation.

Table of Contents:

1.	Introduction	5
1.1	Visualisation	5
1.2	History	8
1.3	Literature Review	9
1.4	Summery of Dissertation	10
2.	The Application	12
2.1	Overall	12
2.2	Components	15
2.2.1	Toolbar	16
2.2.2	Information Window	16
2.2.3	Manipulation Modes	16
2.2.4	Contour Map	18
2.2.5	Acquiring data files	19
2.2.6	Creating datasets of mathematical formulas	21
2.2.7	Colour Shading	23
2.3	User Profile	24
2.4	Alternatives to CoVis3	25
3.	Technical Foundations	28
3.1	Win32	API
3.1.1	Why I chose the Win32	API
3.1.2	Creating a window	29
3.1.3	Event Handling	31
3.1.4	Keyboard Handling	32
3.1.5	Mouse Handling	34
3.1.6	Resources	36
3.1.7	Buttons	36
3.1.8	Edit Controls	36
3.1.9	List Boxes	37
3.1.10	Trackbars	38
3.1.11	Menus	40
3.2	OpenGL	42
3.2.1	The OpenGL architecture	42
3.2.2	Creating an OpenGL window	43
3.2.3	Adapting the OpenGL scene	45
3.2.4	Objects	46
3.2.5	Colours	47
3.2.6	Fonts in OpenGL	48
4.	Data Representation	50
4.1	Equally spaced data points	51
4.1.1	Meshes	51
4.1.2	Isometric surfaces	54
4.1.3	Contour Plots	57
4.1.4	File format	61
4.2	Unequally spaced data points	63
4.2.1	Delaunay Triangulation	63
4.2.2	Contour Plots	72
4.2.3	File format	73
4.3	Colours	74
5.	Learning Outcomes	77
6.	Conclusion & Future Work	78
	Appendix A: Bibliography	79
	Appendix B: Program Structure	81
	Appendix C: Source Code	90