Line of Sight

This webpage is used to showcase/backup some of my coding projects and will get progressively cooler as I put time into it, but havent yet
Feel free to also check out

EE Senior Design - Spring 2014

For my Electrical Engineering senior design project our subteam was tasked with transmitting digital data from a microcontroller to a remote location for analysis. The data being transmitted is filtered EKG (Heart Beat) data from a microcontroller connected via contactless sensors to a marathon runner. Cardiac arrest can occur when running long distances and the idea is to prevent this from occurring by monitoring for irregular heart beats.

Previous work used commercial off the shelf blue tooth communication chips, but were limited to short transmission distances. Our group (Mohammed Alsadah and Me) decided to perform Binary Frequency Shift Keying over FM using TTL level serial data from the microcontroller located on the runner's shirt. For FM reception we took advantage of the RTL2832U usb chip that can be used as a general software defined radio receiver. Note: This was a single semester project, for the first semester we did a EEG controlled (brain wave) robotic hand, but this one is cooler/more EE related imho.

WinFFT Image FM Transmitter
Download WinFFT reception code
YouTube: Reception Test
YouTube: Transmission Testing/Prototyping
YouTube: Final Demo Video (recording was lost sadly)
CE Senior Design - Spring 2011
Garcia Bot at UNT

For my BSCE senior design project our team was tasked with determining the location of robots using the school's wifi network and to have the robots meet when given a command to do so. We were provided four acroname garcia robots which all contain a "gumstix" embedded computer on a chip that runs linux complete with a wifi expansion module for connectivity.

After reading various graduate thesis papers about wifi localization we decided to use what is known as the fingerprinting method. The idea is that you create a database of wireless signal strength readings at various reference points and compare the current location's signal to the database. The "closest" point in terms of signal distance is considered the correct location.

In order to accomplish this, we created various tools to view database information, visualize signal information, etc in addition to the code required for localization and meeting.

heatmap image heatmap image
heatmap image heatmap image
Heatmap images of the embedded system lab and common area between the EE and CS departments.

iwlist_plot screenshot
iwlist_plot application, written using C++ and the MFC api, demonstrating dijkstra shortest path algorithm and database information.
laser_plotembedded lab
Plot of multiple laser scans from the hoyuko URG-04LX ranger

One major obstacle was getting a development environment setup. The garcia robots contain ARM processors that require cross compilation. In order to help future students, we rebuilt the openembedded linux kernel and filesystem with gcc and loaded it onto a microsd card to allow for easy development. We were able to sucessfully locate the robots within 2-3 meters of their actual location and implemented a working meet command.

Download - contains common area dataset three samples per point - contains embedded lab dataset three samples per point - contains embedded lab dataset ten samples per point
scholars_day.pdf - a paper written for UNT Scholar's Day event
altEngine2 - 2009
Cross platform 3d engine. (WinApi, Xlib, OpenGL, D3D9, OpenAL) - YouTube - GitHub - Download - Doxygen - Cgit
(The loading screen is somehow messed up in the video when uploaded to youtube, it worked fine in the fraps capture and the code.)

altEngine2 is the current version of my cross platform 3d engine that I work on whenever I have long periods of free time. It makes use of q3 formatted bsp maps. I'll try to get some better videos as these two were just really for md5 animation more so than demonstrating everything

Major additions:
  • Phong Shading / Lighting
Real time lighting with normal mapping. Colored point lights exist as are defined by the quake3 map and are activated based on distance. I have stencil shading implemented, but shadow volume generation needs work. And most definitely isnt a real time process. I probably need to show case this better as I usually set the ambient lighting high and wash out the detail for development as it appears a bit dark when presented as intended.
  • Collision Detection (That actually works good!)
Stair stepping code could use some work though... kind of a slow hop when near a step.
  • Rigid Body dynamics system
ODE Physics system. This is something I always wanted to program. Integrates netwon's equations of motion and handles collisions of multiple oriented bodies in real time. (ODE as in ordinary differential equation, just now noticed there is a physics engine middleware called ODE now)
  • Finite State Machine Based Menu System
The menu system doesnt use system dependent font rendering but instead renders all fonts as 2d full screen quads that are scaled and translated by a vertex shader and texture coordinates translated to the correct glyph by a pixel shader. Each menu page is encoded as a state with possible state transitions. Most menu systems that I've encountered were composed of very complex code where my code is extremely simple and data driven.
  • UDP based networking
Client/Server networking model that streams sequenced UDP packets and implements reliable message passing based on acknowledged sequence numbers. Still needs work as networked entities are laggy and shake. (lack prediction and interpolation) But reliable message passing works well enough for chatting, and entity streaming works well enough for movement.
  • Bezier Curve Support
I didnt want to implement it, but did so as the missing archways were the most identifiably ugly thing for a while. Took a long time to reverse engineer non 3x3 patch data. But I have code that handles most curves. The lions mouth on q3dm1 still needs work though.
  • OpenGL 3.0 support
Opengl 3.0 removes lots of outdated functionality. All transformations are done in vertex shaders and I am running in forward compatible mode.
  • DirectX 9 support
It works, and needs very little to move onto DirectX10, but could use some more attention since I havent used it in a while. (Dont worry linux still works) I also have a nice system that supports both opengl GLSL shaders and directx HLSL shaders and handles them the same. (This means you need to write the same shaders twice one for each api, but it's better than having to use some slowly updated middleware like CG.) I could probably get my engine working on the iphone if I tried.
Babel Compiler - Spring 2010
Shift/Reduce compiler that uses flex/bison.

Wrote this for a compilers course. It makes use of flex for parsing the input program into tokens and bison to perform the shift reduction of grammars. What did I do you ask? Well I made everything that flex/bison needed to work and wrote the code generation code. This was done in three weekends, the assembly generated is intel style assembly (AT&T style assembly can rot and die) The gnu assembler can assemble intel style x86 assembly easily with a few flags. So the final output can and does work on both windows and linux. The babel language was created by Professor Sweeny, it's basic language, but has all the requirements (loops, if statments, functions, recursion etc)

I really fought the idea of jumping to the end of a function to allocate temporary storage stack space and then jmping back, which is inefficient and therefore morally wrong for me to do as a programmer. (impossible to avoid this with single pass compilation) But I probably should of done it that way anyway as it gets complicated if you dont. I stored all temps on the stack. If anything this should serve as a quick example of how to use flex and bison. [Professor is a linux guy, so I used bzip2]

Download compiler-1.2.tar.bz2
VHDL Projects - Spring 2010

These are projects from an EE digital logic project course. The code should all compile and work in Xilinx and run on a spartan 3e board, but I'm not sure if these are the latest versions we used as I pulled them out of old emails. Mainly have these here in case I want to use the spartan board I bought again.

Project1 is a basic ALU that has four instructions. Add/subtract, logical AND, logical OR.
Project2 is an alarm clock with stopwatch functionality. It works like a typical alarm clock with alarm, am/pm indicator, set buttons etc. The code includes a seven segment lcd decoder, Binary to BCD decoder, counters, clock dividers etc. Most everything is done at the gate level.
Project3 code isnt here, but it was a combination lock. Which is pretty much a finite state machine that accepts keypad input to transition to either an unlock or alarm state.
Project4 is a Reverse polish notation calculator. It has a stack to push operands and can perform addition, subtraction, multiplication, and XOR. This was the final project and I took advantage of process statements this time to make my life easy.
WebGrade ~ 2007
Course management system. (xhtml strict, css, javascript, php, ajax)

WebGrade is a university course management system which was a team project for a Fundamentals of Software Engineering course. I was the team leader of a group of three other students and also acted as lead developer. WebGrade allows an administrator or student to login to manage courses or view grades respectively. It is xhtml strict compliant and makes use of content / presentation division via cascading style sheets. Download it's source code below, username and password is root.

Download WebGrade
altEngine ~ 2006 - 2004
Cross platform 3d engine. (WinApi, Xlib, OpenGL, OpenAL) - Download

altEngine is a first version of my engine. It runs on windows and X windowing systems. (Runs fine on Linux and Mac OSX with X Window extensions installed.) I like computer graphics and hope to add just about everything to this eventually.

renderer pvs textured

Screenshots of q3tourney2 "The Proving Grounds" being rendered. Textures are missing because I didnt go through the trouble of extracting them. It is loading a bsp file directly from the game and performing the pvs calculations. The boxes are bsp leaves.


Screenshot of ageia physx sdk after about 10 minutes of playing with it.


Screenshot of ageia physx sdk a couple of weeks later as I was learning opengl


Screenshot of normal mapped texture with per pixel real time lighting done via GLSL

Update 12/16/2017: Found old physx code, it needs the old Ageia 2.4.4 runtime for it to work -- Download the free Cellfactor: Revolution game and it will install all the necessary runtimes or just watch the youtube video.

So, this was based on the original 2.x Ageia PhysX SDK, later there was a backwards compatibility breaking (rewrite) 3.x SDK released with improvements after Nvidia acquired Ageia, which eventually dropped support for the PPU discrete processor. That SDK was then later deprecated in favor of "GameWorks" sdks, which separate cloth simulation, rigid bodies, fluid, etc from each other into separate sdks. (It was a mistake to separate the development kits imho) One of those SDK's, Nvidia Flex took a completely particle based approach and is pretty impressive -- Most likely started as a fluid simulation and represented solids as particles to reuse existing functionality

Ageia stuff is separate from the old altEngine, I just tacked on it to the end there way back when and havent moved it since
clipMon ~ 2006
LCD Clipboard Monitor. (WinApi, lglcd sdk)

Clipmon is a LCD clipboard monitor for the Logitech G15 Keyboard. (still works on the newer G19 keyboard released 3 years later) It is written in C and makes use of the Windows API and low level logitech lcd sdk (Logitech later released a high level C++ API.) Source code is included with the binaries, I had to write my own word wrapping code because of difficulties using a higher level winapi text function and took a different (ie: weird) approach with exception handling. I wrote this thing in roughly 6 hours and like using it on occasion.

Download clipMon
ircMon ~ 2006
LCD Internet Relay Chat Monitor. (WinApi, lglcd sdk, Winsock)

Like clipMon, ircMon is a Internet Relay Chat monitor for the Logitech G15 Keyboard. It is written in C and makes use of the Windows API, Winsock, and the same low level logitech lcd sdk. Source is not included as it isnt pretty and the irc protocol parser needs work. (IE: It will crash on you.) It worked well enough for me to lose interest in it. -- Added the source code, cause why not, I should fix it one day

Download ircMon
sealstats ~ 2003
Realtime Statistic Aggregator. (Perl, PHP, SQL)

Sealstats generates player rankings and stores statistical data from the Quake3 modification Navy Seals. Based on existing source code given to me by 'LostCause' who created the stats program for Urban Terror, another quake3 modification. I ported the code to work for navy seals and modified/extended existing functionality. A perl script parses the game log file in order to calculate statistics and inserts relevant data into a mysql database via the perl DBD module. PHP is then used to read from the database and display the statistical information. All of which happens in real-time as players play the game.

Upon asking for a logfile to help test the code, the developers of the mod took interest in the program and made it an official part of the navy seals modification. I delivered what I had and they took control of it from there. Images and html code were developed by democritis and other coding work was done by defcon-X.

Download sealstats
ns_dam ~ 2003
Quake 3 Map.

ns_dam is a map for the quake 3 modification navy seals that I made and never released. The files are too large to upload here, (now uploaded as of July 2016) but it is neat and shows some of my more artistic side. (or lack thereof) It has quake 3 team arena style terrain, terragen skybox, and just about every neat feature possible with q3map2 compiler. I did a quick compile of the map a looong time ago so the lighting isnt as perfect as it can be and the screenshots were taken quickly with texture settings set crappily. (mipmap nearest / picmip 1) Doing a good light compile can take days and odd lighting in places can make you have to restart the whole process. (While hoping the small changes you make to fix one thing doesnt break another.)

flag flag generators office stairway screenshot screenshot screenshot screenshot screenshot screenshot screenshot screenshot screenshot screenshot
Download ns_dam.pk3 (33mb)
(pk3 files are really zip files, .map files are included for editing. I think it has some other maps I made in there too if you fire up q3radiant/gtkradiant, but just load the map with /devmap ns_dam)
Note: It does need mapmedia.pk3 from qeradiant and some assets from the navy seals mod (eg: snowy pine tree)

q3f_military ~ 2001
Quake 3 Map.

This is that "other map" that I was referring to, went ahead and bsp'ed it and packed it up nicely, intended for the quake 3 team fortress mod, q3f, run it with /devmap q3f_military

screenshot screenshot screenshot screenshot Imagine the flag being there with electricity coming off those electrodes (if I downloaded the mod) screenshot screenshot screenshot screenshot screenshot screenshot
Download q3f_military.pk3 (17mb)
Papers ~ 2010

I'm going to start writing tutorial like papers mainly as specifications for my own work with hopes that someone may be able to find something useful in my horrible, horrible writing. Links will work when I feel that the papers are developed enough for publication. -- Sorry for taking so long, I wrote most of these papers over the summer, but lost them all when my motherboard died. I'll silently improve these over time.

Quaternions - Example code
Quaternions often misspelled by myself as quanternions. These are a set of complex numbers generalized into three dimensions and can be used to smoothly rotate between two orientations.
Rigid Body Dynamics - Example code
Rigid Body Dynamics, think of it as simulating the physics of dropping your cell phone. This paper describes simulation of rigid bodies using newton's equations of motion and involves some scary math to make bodies rotate correctly in response to torque. Spring based and impulse based collision reponse methods are described. I also cover euler integration and fourth order runge kutta integration.
[I learned from Chris Hecker's tutorials, pixar's physically based modeling paper, and also a bit from Alan Watt's 3d computer graphics book]
Tangent Space
Tangent Space. The final frontier. Tangent space is a coordinate system that best describes the face of a triangle. This paper describes how to find the normal, tangent, and bitangent vectors necessary to create a rotation matrix that will convert points and/or vectors from eye space to tangent space.
Smoothed Particle Hydrodynamics
Tentative - Link is now bad... :( one day I'll get around to it (fluid dynamics is too cool not to)
Particle based real time simulation of liquids that doesnt suck. paper will be based completely on amada's work: