Initial commit

LICENSE.txt

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+BSD 3-Clause License
+
+Copyright (c) 2012, Torsten Stöter
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+3. Neither the name of the copyright holder nor the names of its
+   contributors may be used to endorse or promote products derived from
+   this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

README.md

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+Personal CS Student Portfolio
+=============================
+
+by Torsten Stöter, 2011 Computer Science alumni of Otto von Guericke University Magdeburg, Germany
+
+Welcome to this repository, where I archive and share my student projects centered on visualization and physical simulations. These projects were originally hosted on my former student website. Below, you’ll find a list of these projects, each located in a subdirectory of this repository.
+
+### Fluid Simulation on Curved Triangle Mesh Surfaces
+<table>
+<tr>
+<td width="15%">
+<img src="images/surface-flow.png">
+</td>
+<td>
+<p>Fluss implements my final thesis project &mdash; a simple geometric and physically-based method for simulating fluid flows on curved triangle mesh surfaces. Previous methods for simulating surface flows require parametrizations of the surface globally or locally flattening the surface. However, these parametrizations introduce distortions to the flow. The proposed method operates directly on the triangle mesh, geometrically computing the fluid flow for individual triangles and does not need a parametrization of the surface. The thesis further investigated the numerical and physical properties of the method and demonstrated its accuracy in resolving fluid flows.</p>
+
+Tech: C++, OpenMP, OpenGL, GLUT<br>
+Links: <a href="surface-flow">Source Code</a>
+</td>
+</tr>
+</table>
+
+### Halfedge Data Structure
+<table>
+<tr>
+<td width="15%">
+<img src="images/heds.png">
+</td>
+<td>
+<p>A halfedge data structure allows efficient adjacency queries on meshes. These queries are linear in time with the number of items found, while the data structure is constant in space. For my final thesis project I needed an easy to use halfedge data structure to represent surface meshes. I also wanted to store additional information per face and per edge. However, I couldn't find any suitable existing implementation and ended up writing my own tiny halfedge class, which I want to share. Class heds is my implementation of a simple and tiny halfedge data structure for triangle meshes. It is easy to use and provides basic adjacency queries for vertices, edges and faces. Currently it supports triangle meshes only, which may have boundaries or contain holes.</p>
+
+Tech: C++<br>
+Links: <a href="halfedge-ds">Source Code</a>
+</td>
+</tr>
+</table>
+
+### Grain Growth Simulation
+<table>
+<tr>
+<td width="15%">
+<img src="images/cuggs.png">
+</td>
+<td>
+<p>Cuggs is the CUDA Grain Growth Simulation, a tool for simulating normal grain growth in the recrystallization process of fused metals. It is based on the Monte-Carlo-Potts model and has been implemented using CUDA for parallel execution on the GPU to increase performance. Cuggs allows to simulate and visualize both 2D and 3D grain structures, loading and storing of grain structures and performing statistical analysis on the grain distribution. The program was developed in collaboration with Dr. Dana Zöllner and Stefan Schäfer of the Department of Material Physics / Institute for Experimental Physics at the University of Magdeburg.</p>
+
+Tech: CUDA, OpenGL, GLUT<br>
+Links: <a href="grain-growth">Source Code</a> &nbsp;  <a href="https://vimeo.com/15136929">Video</a>
+</td>
+</tr>
+</table>
+
+### Spinning Top
+<table>
+<tr>
+<td width="15%">
+<img src="images/bk.png">
+</td>
+<td>
+<p>Brummkreisel (German for spinning toy top) is a small demo simulating the motions of a spinning top, after it has been nudged. The underlying physically-based model describing the top's behavior consists of a system of non-linear second-order differential equations and is solved numerically using the classical Runge-Kutta method. A first prototype was implemented in MATLAB, ultimately to develop this three-dimensional real-time simulation, which is visualized by a 3D model of a "Brummkreisel". Plots of a few time-dependent physical quantities give additional information about the oscillation, its amplitude and the rotational speed.</p>
+
+Tech: C, OpenGL, GLUT, MATLAB<br>
+Links: <a href="spinning-top">Source Code</a> &nbsp;  <a href="https://vimeo.com/983003464">Video</a>
+</td>
+</tr>
+</table>
+
+### Lattice Boltzmann Fluid Simulation
+<table>
+<tr>
+<td width="15%">
+<img src="images/lbm.png">
+</td>
+<td>
+<p>This demo shows my implementation of the Lattice Boltzmann Method in two dimensions (D2Q9) with the BGK collision model and bounce-back boundary conditions. The Lattice Boltzmann equations are solved on a 256x256 cartesian grid and the computations are performed on multiple processor cores if available utilizing OpenMP. Using the mouse you can steer a fluid within its rectangular container. You can also draw additional boundaries to create more complex geometries affecting the flow. Advected particles indicate the direction of flow while the speed of the flow is colorized with a blue to white color scale. This demo is also used in an educational course of the Intel Academic Program.</p>
+
+Tech: C++, OpenMP, OpenGL, GLUT<br>
+Links: <a href="lattice-boltzmann">Source Code</a> &nbsp;  <a href="https://vimeo.com/17519091">Video</a>
+</td>
+</tr>
+</table>
+
+### Volume Renderer
+<table>
+<tr>
+<td width="15%">
+<img src="images/volren.png">
+</td>
+<td>
+<p>Mass Carver is my attempt at a basic volume renderer utilizing hardware accelerated 3D textures on graphics cards to display volume datasets at interactive frame-rates. Raw 8-bit volume datasets can be processed and an accompanying metafile provides necessary additional information to built up the 3D texture. Among a description and resolution of the dataset, the metafile also contains an opacity and color transfer function. In the rendering cycle view aligned slices crossing the 3D texture are blended together creating a direct volume image or a maximum intensity projection, corresponding to the render mode selected.</p>
+
+Tech: C++, OpenGL, GLUT<br>
+Links: <a href="volume-renderer">Source Code</a>
+</td>
+</tr>
+</table>
+
+### Image-based Flow Visualization
+<table>
+<tr>
+<td width="15%">
+<img src="images/flowvis.png">
+</td>
+<td>
+<p>An implementation of a few techniques for visualizing 2D vector fields, including extraction of critical points. Besides a modified version of Arrow Plots the visualization methods used are: Line Integral Convolution (LIC), Spot Noise, Texture Advection and simple Integrate & Draw. In my demo program a random vector field on a regular 5x5 grid is created, vectors inside of a grid cell will be interpolated. The output of the program will finally be an image generated with either visualization method chosen by the user, also showing the critical points if desired.</p>
+
+Tech: C++, Allegro<br>
+Links: <a href="flow-vis">Source Code</a>
+</td>
+</tr>
+</table>
+
+### Vertically Driven Pendulum
+<table>
+<tr>
+<td width="15%">
+<img src="images/pendulum.png">
+</td>
+<td>
+<p>This special pendulum is not only swinging due to an initial displacement, but it is also driven by vertical motions of the pendulum's mount. Two java applets demonstrate this pendulum's nonlinear dynamics. This Java program shows the swinging motion for a user defined excitation function, dampening and initial displacement. To solve the pendulum's equations of motion numerically the classical Runge-Kutta method has been employed in combination with finite differences for the second-order derivative of the height profile.</p>
+
+Tech: Java<br>
+Links: <a href="pendulum">Source Code</a>
+</td>
+</tr>
+</table>
+
+
+## License
+
+All projects are licensed under the BSD 3-Clause License. See LICENSE.txt for details.
+

flow-vis/Readme.txt

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+FlowVis2D
+An image-based flow visualization demo
+Version 1.1
+
+By Torsten Stoeter, Aug 25, 2008
+torsten dot stoeter at st dot ovgu dot de
+
+Changelog
+Version 1.1
+	- added texture advection
+
+This program demonstrates my implementation of five different techniques for
+visualizing steady 2D vector fields, I read about in the flow visualization
+class I took. Namely these techniques are: Arrow Plots, Integrate & Draw, Line
+Integral Convolution (LIC), Spot Noise and Texture Advection. The program
+creates a random vector field on a regular 5x5 grid, visualizing it using one of
+the above methods. The magnitude of the vectors can be color coded with either
+color scale and critical points will be shown if desired. Running the demo,
+you'll see a menu to make your choices of visualization technique, color scale
+and if you want to display critical points or not. Please note, that
+computations may take some time, especially for Spot Noise images.
+
+To build the program from source code you'll need to install the Allegro
+library. You can download Allegro at http://alleg.sourceforge.net/. Then simply
+call make -f on the appropriate Makefile (.unix or .win respectively):
+
+$ make -f Makefile.unix
+
+Source code and binaries are provided free of charge and without any warranty.
+Use it at your own risk. You may use my code in your own projects, informing
+me about where and how you use it.
+

flow-vis/Source/ColorScale.cpp

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+#include "ColorScale.h"
+
+ColorScale::ColorScale(int num)
+{
+	scale = new double[num][4];
+	c = 0;
+	n = num;
+}
+
+// note: points should be added in ascending order
+void ColorScale::AddPoint(double v, double r, double g, double b)
+{
+	if (c < n)
+	{
+		scale[c][0] = v;
+		scale[c][1] = r;
+		scale[c][2] = g;
+		scale[c][3] = b;
+		c++;
+	}
+}
+
+// note: expects scale array to be sorted in ascending order
+void ColorScale::GetColor(double v, double& r, double& g, double& b)
+{
+	int i = 0;
+	double w;
+
+	if (v < scale[0][0])
+	{
+		r = scale[0][1];
+		g = scale[0][2];
+		b = scale[0][3];
+	}
+	else if (v > scale[c-1][0])
+	{
+		r = scale[c-1][1];
+		g = scale[c-1][2];
+		b = scale[c-1][3];
+	}
+	else
+	{
+		for (i=1; i<=c; i++)
+			if (scale[i-1][0] <= v && v < scale[i][0])
+				break;
+
+		// linear interpolation
+		w = (v - scale[i-1][0]) / (scale[i][0] - scale[i-1][0]);
+
+		r = (1-w)*scale[i-1][1] + w*scale[i][1];
+		g = (1-w)*scale[i-1][2] + w*scale[i][2];
+		b = (1-w)*scale[i-1][3] + w*scale[i][3];
+	}
+}
+

flow-vis/Source/ColorScale.h

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+#ifndef COLOR_SCALE_H
+#define COLOR_SCALE_H
+
+class ColorScale
+{
+	private:
+		double (*scale)[4];
+		int n, c;
+
+	public:
+		ColorScale(int num);
+		void AddPoint(double v, double r, double g, double b);
+		void GetColor(double v, double& r, double& g, double& b);
+};
+
+#endif
+