The Deambulatory Matrix

Wireless NES Controller Doorbell (2008)

2011-04-23T15:45:00.000-07:00

When we moved into our condo, we found a wireless doorbell module; the electronics still worked fine, but the case of the doorbell itself was broken beyond repair. My uncle had recently scored a number of NES and accessories a a flea market, so I thought it would be neat to turn one of the controllers into a doorbell.

This is a pretty simple hack, since all I really did was replace the button from the original doorbell with the buttons from the NES controller. Nevertheless, a short video about the doorbell on youtube has since garnered tens of thousands of views:

It's cropped up on random websites (even Gizmodo), and I am frequently asked for more details about the build, so here goes.

Just replacing the button would have been pretty simple, but I also wanted to add feedback to the user to tell them something was going on, since it's not immediately evident that the controller serves as a doorbell. (After many years of use, however, I've only had one person knock because they were unsure what to do.) I figured an LED that lights up when the user pushes a button should do the trick.

In order to figure out what the best way to wire all that up was, I wanted to trace out the doorbell emitter circuit - the circuit behind the button you push to make the chime ring. To do this, I took pictures of both sides of the circuit:

Top side of the circuit, with the components.

Underside of the circuit, with the button, a diode, a resistor, and a Circuit-On-Board (COB).

I loaded up those pictures as two layers in a Paint.NET document. With a bit of reorienting/resizing, I was able to align the pictures so that they lined up with each other, and I could see either side of the board by toggling layer visibility. (Note that one of the layers has to be flipped for this to work; you can tell from the pictures above that the word "ALKALINE" reads backwards.) It helps to make the top layer partially transparent when doing this:

Both layers lined up. You can tell that the components from the top side align with the solder pads on the underside.

Then, I used a small Wacom tablet to paint over the backside traces and components in a new layer:

Backside with hand-drawn traces.

Then, keeping the painted traces visible, I hid the circuit backside and showed the frontside:

Frontside with hand-drawn backside traces and components.

This is where you can tell that the job is made a bit more difficult because of the perspective foreshortening, since the red traces don't exactly line up with the component legs. To mitigate this, I could have used a flatbed scanner to take the pictures (by putting the electronics on the bed), or perhaps taken the picture from a bit further back (at the expense of resolution).

Nevertheless, by twiddling the transparency of the front layer back and forth, I was able to trace the front-side components with the Wacom as well:

Traced frontside components.

And then, hiding everything but the hand-drawn stuff, I wound up with the following:

Final traced circuit. (Image flipped horizontally from previous shots for legibility.)

From this point, I was able to transpose the circuit by hand onto paper:

Hand-drawn circuits. The top circuit is the first jot. The bottom one is the same circuit, but laid out differently to increase legibility. The components I added are highlighted in red.

On the bottom circuit, you can somewhat delineate the stages of the circuit. The battery is at the far left, supplying voltage to the the input stage (R3, S1, C1) and the COB. S1 is read by the COB, and when a press is detected, the COB drives the transmitter stage on the far right.

To see how to merge the NES controller with this circuit, one needs to know a bit about how NES controllers are made. It turns out to be quite simple: all the buttons are wired as independent inputs to a shift register. Since the doorbell circuit has only one input, all I needed to do was to wire up all the controller buttons in parallel to S1, so that pressing any one button would close the circuit and ring the bell.

Additionally, to light up an LED when the button is pushed, I needed to wire up the LED (and a current-limiting resistor) in such a way that a voltage differential would exist across the LED when a button was pushed. By analyzing the circuit above, it is possible to see that the input to the COB is active low - when S1 is closed, it brings the line read by the COB to ground. (R3 acts as a pull-up resistor when S1 is open.) Thus, an LED between the positive end of the battery (the net labelled N8 in the diagram above) and the input line read by the COB (net N9) will light up when a button is pressed.

Both these modifications are shown in the above diagram, in the red rectangle.

However, just adding the LED and the NES buttons in parallel caused a problem to occur: the doorbell wouldn't ring anymore! This is because the buttons in the NES controller are made of little graphite pads that have a definite non-zero resistance, unlike a regular pushbutton. (I seem to recall testing buttons up to a few kilohm.) In effect, the NES controller buttons are creating voltage dividers with R3; if the resistance from the pushbuttons is too large, the voltage read by the COB does not drop low enough for it to detect a button press.

The first fix I made for this was to desolder R3 and replace it with a bigger resistor, to "recalibrate" the voltage divider to account for the higher resistance of the NES controller pushbuttons. This required careful tuning, because the COB also requires a minimal amount of current to flow in for a button push to be detected; making R3 too large chokes off the current flow, once again preventing the doorbell from ringing. Add to this the fact that the LED steals even more current from the COB and you have a tricky trial-and-error process to find values for R3 and the current-limiting resistor - values which allow the bell to ring, while allowing the LED to light up "sufficiently".

Once I had the electronics working, it was a matter of fitting everything into the controller casing. Here are a few steps from the process:

The discombobulated controller.

Getting ready to make some space inside the case.

Part-way through cleaning up the case.

Testing the fit.

Another angle on fit testing.

Soldering up the buttons with the fire-started I had at the time.

Buttons soldered up in parallel.

Testing the cutout for the chime circuit.

Final look, with the LED in the top-right.

Part-way through assembly.

Putting in the LED.

Mounted on the door using "temporary fixtures" which are still there three years later.

This worked great! For six months.

When winter came, the bell stopped ringing - the resistance from the graphite pads inside the controller had risen, and the COB no longer detected button presses. Tarnation! The definitive fix was to use a time-proven trick to revitalize dead NES controllers, which is to use double-sided tape to affix little aluminum pads to the rubber behind the buttons, effectively replacing the graphite. This dropped the NES button resistance by three orders of magnitude, and everything has worked since then.

Finally, I should mention that this was an afternoon hack that performed because I saw an opportunity to make something amusing. People often point out that the buttons could make different sounds; that is quite true, and it would have made it even cooler! Sadly, with the parts I had on hand, this would have taken quite a bit more effort. But worry not! Somebody has in fact built such a device, and you can see a video here.

Lessons Learned:

The internet is an awesome place - I never would have thought so many people would see the video.
The doorbell makes for a great conversation starter with delivery people.
Reverse-engineering circuit layouts can actually be a good time.

Digital Chromatic Guitar Tuner (2008)

2010-11-15T19:40:00.000-08:00

Back in 2008, we organized a family gift exchange for Christmas, and one of the items on my brother-in-law's want list was a chromatic guitar tuner for his band Guajira. Seeing this, I began thinking about how one would go about building such a device, and, thinking it would make a cool Christmas vacation project, I decided to try my hand at it. After a bit of research, I started designing on December 19th; after much programming, building and testing later, I finished with moments to spare on December 24th.

Here is the video I posted shortly thereafter:

Over time the video has elicited many technical questions from viewers, questions which I couldn't answer in full detail until now for reasons unnamed. I'll try to provide a bit more detail than usual in this writeup, but keep in mind this project is almost two years old so the details are getting hazy. :P Also, since I no longer have the device in my possession, having given it away at the gift exchange, I'm unable to take new pictures of it, and I'm stuck with cruddy webcam pics.

The Tuner

As seen in the video, the device has a few functions. It accepts analog input from a standard 1/4" TRS jack, performs monophonic pitch detection on it, and either displays tuning information or outputs MIDI signals based on the detected pitch. Tuning can be adjusted by moving A up or down a few hertz from 440. There is a bypass switch, a backlight switch for the LCD and a contrast ratio pot; the whole thing runs on either DC power or a 9V battery.

You can get the code here.

The Electronics

First off, I am far from being proficient with hardware design; my experience is quite limited, and I'm much more comfortable with digital than analog. I didn't have an oscilloscope when I built the tuner, so I did a lot of fiddling with component values using just a multimeter and a few speakers to listen for noise. (I've since acquired and assembled a DPScope, they're excellent.) As such, the design process was very much empirical, and I had fun swapping parts to see what worked best without the worry of frying a few pennies' worth of electronics.

Also, missing from these schematics is an Arduino. I used a Real Bare-Bones Board from Modern Device, which I recommend; cheap, tiny, easy to assemble. Signals named A5, D4, D5, D6 etc. in the following schematics connect to the pins with the same name on the ATmega168.

There were a few LED connections and simple pushbuttons, whose circuitry I didn't outline here. If you're wondering how to connect such devices to an Arduino, I would suggest the Arduino Playground as a starting point - it's a great wiki.

The Power Stage

The power stage, which provides regulated 9V power to the rest of the circuit.

POWERSW is the system's power switch, which does its job by connecting the system ground to the power jack's ground pin (pin 3 on DCEXT).

In the case where no external jack is connected, DCEXT's pin 2 is connected to pin 3; the LM317T remains unused, and the 9V battery directly feeds VCC and GND.

In the case where an external power jack is connected, DCEXT's pin 2 remains floating, which disconnects the battery ground from the system. The LM317T turns on and regulates outside power; voltage is adjusted to 9V using VADJ, as per the 317's datasheet. CFILTPOWER is there to smooth out ripple, acting as a low-pass filter. I had a 100uF lying around so I used that. (The LM317 datasheet recommends 10uF or more.)

What I learned:

The battery leaks 6mA through R2 and VADJ, which is quite crappy.
You mileage may vary when adding a filtering capacitor before the LM317T; I found it made no discernable difference in this case.

The Input/Bypass Stage

Input and bypass.

Well, it doesn't get much simpler than this: a dual-pole, dual-throw switch that either routes the signal from the input jack to the circuit or right back out, like a 2-way multiplexer.

What I learned:

The foot switch was difficult to source, and once I found an appropriate one, it took up LOTS of space in the case - on the order of two cubic inches. I hadn't really planned for this.

The Buttons

Button wiring; not much to see here, just a simple pull-up resistor setup.

The LCD Stage

LCD connections.

Once again, pretty standard stuff. The LCD I used had a backlight, hence BACKLIGHTSW. Contrast adjustment is done using RCONTRAST, on pin 3. Pins 4, 6, 11, 12, 13 and 14 form a 4-bit data connection to the Arduino, as described on the Arduino LiquidCrystal page.

What I learned:

The cheap surplus MTC-16205D LCD I used required some extra "convincing" to boot up properly. I included the LiquidCrystal library directly in the PDE and modified the source to get it working.

The MIDI Stage

MIDI connector connections.

More standard fare; I recommend the ITP page about MIDI output from Arduino, it's great!

The Amplification Stage

The amplification stage, which takes the input from the guitar and feeds it to the Arduino. (See note below about INPUTCOUPLING capacitor, I think I had the wrong value marked down.)

This stage is the one I spent the most time trying to get right, and (I'm guessing) probably the portion of the circuit which is of most interest to the people trying to build something similar. I'm positive there are many grievous design errors in here, but in the end I got it working well enough.

Overall, what this circuit does is take the input, adjust its volume (VADJ), amplify it (the LM386), and convert it to a form which the Arduino can sample (R7/R8/D1/D2).

I began with the application entitled "Amplifier with Gain = 200" from the LM386 datasheet:

Volume adjustment is done using VADJ1 as a voltage divider. I preferred this approach over adjustable amplification gain because the physical mapping of "angle of the volume potentiometer" to "amplification volume" was easier to control this way; judging by the LM386's typical applications, this seems to be an oft-favoured way of doing things.
The LM386 is setup as a fixed gain amplifier, whose gain is adjusted to 200 using CFILT3, as per the datasheet.
The output is fed through a low-pass filter built using CFILTAUDIO and R6; this rejects unwanted noise from the amplifier. Without it, you can hear AM radio faintly, and there is a lot of crackle in the amplified sound.
An output coupling capacitor, OUTPUTCOUPLING, blocks any DC bias at the output of the amplifier, preventing it from leaving that stage and entering the following portion of the circuit. (If a speaker was connected directly to the output of the amplifier, DC would flow through the speaker's coils, which are delicate and may heat up. Here, instead of a speaker, we have an Arduino; more on this below.)

You'll also note that I made a few modifications:

I added R5 to set the minimum amplification level. R5 effectively create a "floor" for the voltage divider formed by R5 and VADJ1.
I added the INPUTCOUPLING capacitor to fix a buzzing problem; I think I wound up using a bigger value than 0.011uF, however, since that's an unusually small value for a coupling capacitor, one which I think might have filtered the signal a bit too much. Much like the output coupling capacitor, this prevents DC from entering the op-amp (LM386) and being amplified, offsetting the output signal. I distinctly recall trying multiple values on for size here.
Instead of connecting a speaker to OUTPUTCOUPLING, I connected an analog input on the Arduino so I could sample the signal.

There is a small problem here: you can't just take the output from the LM386 and connect it to the Arduino pin. This is because the amplifier, as set up, outputs signals from -9V to 9V; under normal conditions, an Arduino can only sample analog signals between 0V and 5V, so a direct condition would not only saturate the ADC but likely damage the Arduino's input.

To rectify this situation, we have to do two things. Firstly, we can add D1 and D2 as shunt diodes to clip the signal to 5V and 0V, respectively. In practice, the forward bias of the diodes allow the signal to exceed the allowed range slightly, but the excess shouldn't damage your Arduino. I used fast-switching 1N914 diodes, which I just realized have a forward bias voltage of 1V; this means the signal can still range from -1V to 6V, which is probably a bit much to be safe. Nevertheless, I've had no problems so far... knock on wood. :P

The second thing we must to is a bit trickier. The output of the LM386 centers around 0V, which is half-way between -9V and 9V. The Arduino, however, has a mid-range input of 2.5V, which is half-way between 0V and 5V. If the Arduino just samples the signal as clipped by the diodes, anything below 0V from the op-amp will get clipped and sampled as a 0 by the Arduino. This means that the Arduino would only see the top half of the waveform from the LM386, which would make it difficult for us to have an accurate "big picture" of the waveform for frequency analysis.

To fix this, we must add a DC bias to the signal, to "re-center" it around 2.5V. This is done with the help of R7 and R8, which form a sort of voltage divider. Since R7 and R8 have the same value, when no AC is coming through the coupling capacitor, the voltage at the Arduino pin is 2.5V. When the LM386 is busy amplifying a signal, the AC component of the amplifier's output makes it through OUTPUTCOUPLING, nudging the rest point of 2.5V up and down, if you will. (It is important to use large values for R7/R8 in order to raise the cutoff frequency of the high-pass filters they form with the OUTPUTCOUPLING capacitor.)

You may wonder what we do about scaling the range of the signal. The answer is: nothing, VADJ1 takes care of that for us. Since different guitar pickups have different signal levels, on the tuner I built, the user adjusts VAJD1 using a potentiometer. LEDs indicate amplified signal strength for calibration.

What I learned:

Despite warnings from my E&CE241 teachers and lab instructors to the contrary, as long as you keep the datasheet warnings in mind and your finger not too far from the kill switch, it is perfectly fine to try various component values in your circuit. In fact, it's fun and instructive, and I plan to do more of it in the future.

Notes on the Circuit as a Whole

Seeing as how it's performing signal analysis, the tuner is fairly sensitive to power supply noise. About a year after the tuner was made, I took it in for a "service call". The unit sometimes no longer detected pitch properly; after some testing, I realized this only occurred if the LCD backlight was on and an external power adapter was used. It seems that when the LCD backlight is on, the extra load on the power supply stage increases the ripple which makes it through to the amplifier stage and Arduino supply (which, in turn, probably affects the reference voltage of the ATmega168's ADC to some degree, even though the Arduino has its own regulator). My hypothesis is that this is due to failure of some kind in the power supply filtering; possibly my recycled 100uF capacitor gave up the ghost or otherwise deteriorated; perhaps my soldering was suboptimal; perhaps there are gremlins in the box. In any case, this is very similar to what occurred on a breadboard when I accidentally knocked the 100uF capacitor out.

The Software

The software does a few things. I won't really discuss the pushbutton logic and so on here, since there is a lot of documentation available about that. The two things I get the most questions about are the pitch-detection algorithm and the method I used to output slim vertical bars on the LCD.

How to Perform Pitch Detection

I tried a few "heuristic" algorithms - counting zero crossings, analysing the first-order derivative, and so on - but these often depended on the shape of the signal, which gave erratic results. (Even a single vibrating string has multiple harmonics which make such approches difficult to work with.) I wound up settling on a home-grown variation (and simplification) of an algorithm called YIN, which you can find described here. Based on autocorrellation, this algorithm worked much better than all other approaches. However, as you might tell from the paper, it is relatively expensive in terms of computation and memory, at least as far as an ATmega168 goes. (Newer Arduinos now use the ATmega328; double the SRAM goes a long way, but you might be constrained by the speed at which you can process the data.) The challenge was to adapt YIN to make it work with a 16MHz CPU that has no FPU and a few hundred bytes of available RAM.

I won't explain the full details of YIN here, but I will explain the gist of it, to show how I adapted it for the Arduino. Autocorrellation-based approaches are actually reasonably simple to visualize. Given a quasi-periodic signal like that produced by a vibrating string, the idea is to take the original waveform:

The basic sampled signal.

And then, we create a virtual copy of the signal, shifting it over a bit:

Copy of the original signal.

Then, we compute some function of the area between the two resulting signals, shown in purple below:

The idea is to keep sliding the copy over until the area between the two resulting signals is minimized. Notice how the red copy keeps sliding over to the right, and how it gets closer and closer to "matching" the blue copy again.

In practice, the steps are much smaller. I made them a bit larger above to demonstrate the idea. However, since we're getting quite close to the red waveform overlapping the blue one again, for the purposes of illustration, let's reduce the step size a bit. (Again, the actual algorithm tries many, many small steps.)

(Pretty close here!)

As you can see, in the third picture above, the two curves came pretty close to overlapping. That corresponds to the moment where the purple area - a function of the area between the curves - was minimized. Once you figure out the offset between the curves for which this area is minimized, you can calculate the corresponding pitch with the following simple equations:

So that's the general idea. But how do we make it run on Arduino? Put another way: what is it that's prohibitively expensive about YIN and prevents it from running on the ATmega168? In practice, I found the two constraints were the time spent computing the value of the difference function (related to the "size" of the purple area above), and keeping a tight reign on the memory requirements of the sampling buffer.

The first hurdle you run into is floating-point math support; simply, there is none on the ATmega168, so you have to give up on floating-point math in any performance-critical portions in the code. I used fixed-point math where I required fractional quantities in the code.

Next, as with most every decision when building gizmos, you have to start thinking about tradeoffs. The difference function used by true YIN works by iterating over all samples in a given window, subtracting the value of the red curve from that of the blue curve and squaring that difference, summing all values thus obtained. The first change I made was to give up on the squaring operation, which required a lot of expensive multiplications, and instead simply compute the absolute value of the difference at each sample:

where tau represents the offset at which the difference function is being evaluated.

In many ways, the revised version is related to the average magnitude difference function (AMDF) mentioned in the YIN paper, only without the averaging operation. Losing the squaring operation may introduce inaccuracies in our detection, but it keeps the general shape of the resulting function looking pretty close to the original while giving us huge improvements in executing speed, so it works out. (Critically, the minima and maxima of both equations occur for the same values of tau.)

That really helped speed up execution, but it was still too slow and memory-intensive. As it turns out, if you can reduce the size of your buffer, you also gain in computation time, because you have fewer samples to process - two birds with one stone! So the next step was trying to figure out a buffer size for which the computation was fast enough, while maintaining the required pitch detection precision.

By "maintaining the required pitch detection precision", I mean that as the wavelengths get shorter and shorter (i.e. as pitch gets higher), a period will take up fewer and fewer samples in our buffer. See the following exerpt from a small helper worksheet I made:

	Frequency (Hz)	Cpu Cycles Per Period	seconds per period	samples per period
A	55	290909.09	0.01818	174.83
A#	58.27	274581.62	0.01716	165.01
B	61.74	259170.54	0.01620	155.75
C	65.41	244624.41	0.01529	147.01
C#	69.3	230894.7	0.01443	138.76
D	73.42	217935.57	0.01362	130.97
D#	77.78	205703.79	0.01286	123.62
E	82.41	194158.52	0.01213	116.68
F	87.31	183261.24	0.01145	110.13
F#	92.5	172975.58	0.01081	103.95
G	98	163267.21	0.01020	98.12
G#	103.83	154103.72	0.00963	92.61
A	110	145454.55	0.00909	87.41
A#	116.54	137290.81	0.00858	82.51
B	123.47	129585.27	0.00810	77.88
C	130.81	122312.21	0.00764	73.5
C#	138.59	115447.35	0.00722	69.38
D	146.83	108967.79	0.00681	65.49
D#	155.56	102851.9	0.00643	61.81
E	164.81	97079.26	0.00607	58.34
F	174.61	91630.62	0.00573	55.07
F#	185	86487.79	0.00541	51.98
G	196	81633.6	0.00510	49.06
G#	207.65	77051.86	0.00482	46.31
A	220	72727.27	0.00455	43.71
A#	233.08	68645.4	0.00429	41.25
B	246.94	64792.63	0.00405	38.94
C	261.63	61156.1	0.00382	36.75
C#	277.18	57723.67	0.00361	34.69
D	293.66	54483.89	0.00341	32.74
D#	311.13	51425.95	0.00321	30.91
E	329.63	48539.63	0.00303	29.17
F	349.23	45815.31	0.00286	27.53
F#	369.99	43243.9	0.00270	25.99
G	392	40816.8	0.00255	24.53
G#	415.3	38525.93	0.00241	23.15
A	440	36363.64	0.00227	21.85

Prescaler	7
ADC Divider	128
Clk/sample	13
F_CPU	16000000
SampleRate	9615.38

See at the end there, around the 440Hz mark, rounding up the 21.85 gives 22, and rounding down the 23.15 gives 23 - that means that using integer buffer offsets (integer values of tau) in the formula above, it would become difficult to differentiate consecutive semitones starting around that A.

One way to increase the precision would be to reduce the prescaler value on the ADC and sample twice as often, which would mean reducing the speed of the code by half and growing the memory by a factor of two. But what is the exact buffer size we're talking about here? What would be the minimal buffer size required to work with the YIN and the frequencies we want to analyze? Well, we need a minimum of two full periods being sampled, in order to be able to copy the first period over the second. Looking at the above table, if we set our minimal frequency to 55 Hz, 175 samples are required to sample a full period, so the minimum size of the buffer would be 350 samples.

The above table shows that these settings are sufficient for coarse precision, around 100 cent of a semitone at the highest frequencies. This is what the code uses for perform pitch detection when in MIDI mode, because it is important to reduce latency (and thus minimize computation). However, 100 cent is hardly sufficient to perform precise tuning of guitar strings, so we must dive further.

I use another trick from the YIN paper: sub-sample interpolation. The idea is simple. In practice, the offset at which the difference function is minimized will never be an integer value; it will be a fractional value, meaning that you have to shift the red copy of the waveform over by a fractional number of samples for the two copies to line up perfectly. Unfortunately, we only sampled the signal at specific intervals, so in order to be able to "resample" the signal at fractional offsets, we reconstruct an approximation of the original, true, analog signal by interpolating between the samples we took. Where YIN uses quadratic (second-order) interpolation, however, I was limited to linear (first-order) interpolation by the processing power. Nevertheless, this provides greatly-enhanced precision.

In the end, to get everything integrated and running, I wrote a small set of classes that allowed me to profile single statements as run on the actual hardware. I also used avr-objdump to disassemble the code produced by the compiler and understand where the inefficiencies were. (There was no need to hand-assemble code; the compiler does a fine job as long as you use the correct datatypes.) I fiddled around with the sampling precision (the ADC on an ATmega168 can sample up to 10 bits of precision), the minimal detection frequency, and the interpolation step size a great deal until I settled on 8-bit samples, a minimum frequency of 60 Hz, and a prescaler value of 7, for a final buffer size of 321 bytes. The sub-sampling code uses fixed-point math with a 5-bit fraction, and it solves up to the least significant bit when finding the minimum in the difference function; thus, the tuner has a theoretical accuracy of 1/32th of a sample, or approximately 2.4 cents of a semitone at 440Hz (3.8 cents at 880Hz).

(The code applies a small amount of low-pass filtering to the final computed pitch value in order to smooth out the display on the LCD.)

The LCD Driver

Rendering the thin vertical bars on the LCD is actually not very complex. Most LCD drivers have a small area of memory called CGRAM, short for Character Generator Random Access Memory, which allows you to create a few custom characters for display. Since the display matrix of the LCD I used was 5x7, I merely created five custom characters, each which a different column of dark pixels. Turning on a given column of pixels then becomes the simple matter of writing the correct custom character to that location on the screen.

Scary Pictures

As mentioned above, about a year after hacking this thing together, I took it in to replace the battery. By this point, my digital camera was repaired, so I snapped a few glorious pictures of the complete mess that it is.

Digital Fluid (2000)

2010-08-22T15:15:00.000-07:00

After spending time teaching my computer how to solve Rubik's cubes, I started thinking about writing something that would cater to my lifelong fascination with gooey matter and infinitely-derivable functions. The first generation of GPUs had just come out (hardware transformation and lighting, oh my!) and it was time to put my 450$'s worth of graphics hardware to work. Other than playing games, of course. Ahem.

By tinkering over the course of a few nights, I wound up writing this little fluid simulation. As it turns out, most of the computation performed wound up on the CPU, so it was taxing little more than the transfer rate of my AGP 4x bus. However, it does shun vendor-specific extensions in favor of multipass rendering to layer the specular highlights onto the texture map.

The fluid patch is implemented using a height field; normals and other epiphenoma are derived from the vertex positions. Texture coordinates are calculated using Snell's law, by putting the texture on a virtual plane behind the fluid patch.

The simulation itself isn't really that interesting from a mathematical standpoint - I was just experimenting, so all the code is ad hoc. The positions are animated using different models. For liquids, linear combinations of many simple closed-form sinusoidal decay solutions are used. For the gooey-looking ones, a simple spring/damper model is used.

(Browsing this code ten years later, I can say that this being my second C++ program, the code stank a bit less than the cube solver. :P )

Be sure to pick HD if available over your connection... the low-resolution version looks like a tie-dye cow.

Lessons learned (or points confirmed):

Programmer art sometimes far outlives its intended longevity... As of this writing, 10 years later, I still haven't replaced that Paint-produced bitmap.
Stuff doesn't necessarily need to be complicated to look decent. In fact, the simpler it is, the easier it usually is to tweak the way you want it. (Recall that this was in year 2000; register combiner cards were still quite mainstream.)

Rubik's Cube Screen Saver (2000)

2010-08-22T12:25:00.000-07:00

Around the same time I was given my first copy of Visual Studio, I bought the OpenGL Superbible. Feeding these two items through the transfer function of my deranged brain, I wound up brewing the following program as a first foray into both the worlds of C++ and modern API-based graphics programming (as opposed to writing to the metal).

The program solves rubik's cubes, bouncing them around the screen:

The algorithm is the same I first learned to use when solving the cube by hand - the original Singmaster method - and it's far from optimal. I recorded sequences of moves interactively using a built-in "move editor", then wrote code that analysed the state of the cube and chose the algorithm to play back. The debug mode output looks something like this:

Lessons learned:

As a first contact with the world of hardware abstraction layers, in terms of API design, OpenGL and GLUT are infinitely friendlier than DirectX 5.0.
Do read your employment contracts closely. I got into somewhat serious trouble for posting a copy of this on NeHe, believing the IP belonged to me since I had created it on my own time. Not so.
A 2,300 line switch statement does not constitute "artificial intelligence". (I still laugh this one today. In my defense, it's not because I didn't know better in terms of design; it's more that I was still learning so much about the language at the moment that there were more pressing points than learning about the constructs which would have enabled me to organise my code in a cleaner fashion.)

Greece 2010 - July 23rd - Home, Sweet Home!

2010-07-28T16:20:00.000-07:00

After an outstanding breakfast in the Plaka, we hopped on the subway to the airport. A relatively short but wobbly flight to Paris later, we hurried across terminals at Charles-de-Gaulle to catch our connecting flight, arriving just as boarding began.

Our flight back across the ocean, the movies we watched were punctuated by the screams and kicks of the young'un beside me. Though there was a relatively long line at customs in Montreal (about an hour), the guard pretty much waved us on with almost no questions, in stark contrast to the occasion of our return from the Dominican Republic.

Oh, the sweet feeling of crashing into your own bed after weeks away.

A very special, smooshy thanks to Laurence for many of the great pictures and fact-checking! Any errors are mine, and any things that make you go "wow" can be attributed to her.

Greece 2010 - July 22nd - Back to Athens

2010-07-28T16:18:00.001-07:00

After Mount Olympus, our trip wound down as we took a bus out from Litohoro to Katerini, and from there took a train back to Athens.

I had a stupendous shower in our Athens Backpackers suite, and apparently exhausted the country's hot water supply. There was none left for Laurence afterwards. :-(

We had one last supper in view of the Acropolis, on Makri street.

Greece 2010 - July 21st - What Goes Up, Must Come Down!

2010-07-28T16:18:00.000-07:00

We had a surprisingly good night's sleep at the refuge - over ten and a half hours.

Accomodations in the refuge.

Main hall in Refuge SEO.

Can you spot the face of Zeus here?

We walked out to one of the nearby peaks, Toumba, to scope out the other side of the mountain.

Northwestern view.

View of the peaks from the Western side.

We set out clambering down shortly thereafter. We decided to take a different path down, about 13.5km. This took us about 4.5 hours.

Plateau of the Muses seen from the North.

The three human-made rock formations we had seen from afar the previous day.

Shepherd dogs admiring the view.

Mules! These must have set out really early, because it's a long way down from here and it's only mid-morning.

Crooked trees! (Actually, the trees grow straight up - the camera was tilted with the slope to take the picture.)

Back in Litohoro, all filthied up and war-torn from the two-day hike, we took baths. And then we promptly returned to the famous Gastrodromio for more outstanding food. Older men played a card game tournament of sorts nearby. (Our waiter identified the game as "Kseri".)

Greece 2010 - July 20th - Climbing Mount Olympus

2010-07-28T16:16:00.000-07:00

By this point all the easy stuff was done, and we had kept the best, but hardest, challenge for last: a hike up Mount Olympus.

Getting dropped off by our "personal" taxi driver Ioannis in Prionia, at the base of the valley, we set out to climb up to Refuge A.

Our target. This was one of the very brief and rare moments where we could see the peak from the base or vice versa.

A short while into the hike, we were already nearing the cloud cover.

Clouds just barely a few meters above our position.

It's going to be above 30 degrees Celcius that at the base that day, past the middle of July, and here we are trekking across snow. And we're not even close to being half-way up yet!

Lots and lots of snow, but it's "ski de printemps".

A look back down, to the path we just recently walked.

Getting close to the clouds.

Refuge A! Time for some veal spaghetti and, as always, Greek salad.

Mules bringing up supplies to the refuge.

Having started at about 9:30am at the bottom, we got to refuge A just past noon. We rested, ate, and gathered information about the rest of our planned route. We still had a bit more than half to go.

Leaving around 2pm, we kept walking through the clouds.

An ethereal setting, with the sun getting close and the clouds letting up.

We are now occasionally above the clouds, on the E4 international hiking path for the moment.

Rest.

When we are not above the clouds, we can barely see feet ahead.

Across the mountain to another stone arm flanking the valley.

You can just barely make out three human-made stone piles at the top left there, at the edge of the Plateau of the Muses.

You don't want to fall down here.

We are so high up by now that the views are similar to those from a landing plane.

Idem.

Brief rest before going on.

Barren lands from now on.

One of the peaks with the sun behind it.

This picture cannot impart the sheer steepness of the slope below. You can see Refuge A through the clouds.

One of our first peeks at a summit refuge. Still quite a ways to go!

The path leading across to the Plateau of the Muses, where the refuges are.

Reasonably sheer drop.

Brief moment in a dark cloud, where you pretty much can't see anything.

The valley below, with Refuge A.

Where we came from. Clouds are fewer and further apart here.

Our first glimpse of Refuge SEO (on the left, where we slept) and smaller Refuge C, on the right. The green area beyond is the Plateau of the Muses.

Refuge SEO about to be swallowed by a cloud.

We reached Refuge SEO around 5:30pm. All in all it took us about 6 hours for the ~9km hike from our starting point, which we gather is about the norm. At the Plateau des Muses, it was 12 degrees Celcius inside the refuge, before they turned on the heat, so that's quite a temperature gradient along the mountain - a difference of about 20 degrees Celcius with the base.

Setting sun.

Peak by moonlight.

Before hitting the sack, we had some goat soup with Greek salad, which was exactly what the doctor had ordered. In the mountain, I was expecting astronaut food; the actual quality of the food in the refuges left me astounded and surprised. It's not merely good, it's great, and it's not even more expensive than elsewhere in the country.

I was fast-tracked through about ten years of Scout training in order to use the facilities for my ablutions, however. And you really want to make sure that you take care of business before going to bed, because the prospect of hitting up a floodlit, draughty, unheated, Turk-style can in the middle of the night because you had one too many sips of tea is enough to make you hold it in until morning. (The reason for this state of affairs is that the washroom can be independently access from the outside with boots on, and as such, is not part of the enclave of warmth and slipper-bound comfort.)

Greece 2010 - July 19th - Creeping Up to Mount Olympus

2010-07-28T16:10:00.000-07:00

The 19th was pretty uneventful - we simply travelled from Kalambaka to the town at the base of Mount Olympus, Litohoro. We had a great, hearty meal at Gastrodromio to prepare for the next day.

In my mind, "Gastrodromio" conjures a picture of the Thunderdome from Mad Max III crossed with some kind of gigantic, disorganized kitchen. However, the food is exquisite, and I must thus surmise that the first part of the name refers to "gastronomy." I sure hope it's planned that way, because in Québec, a restaurant whose name begins with "gastro" probably wouldn't fare long.

Greece 2010 - July 18th - Meteora

2010-07-28T16:06:00.000-07:00

With a long day ahead of us, we set out early and began the hike. We planned on walking to all monasteries. We got to visit five of the six, and only missed out on the last one because our opening hour information was not valid.

This is the day where we snapped the most pictures of the entire trip - by far - so I'm going to take the liberty of exploding your bandwidth limit here.

We started out on the Kalambaka side, with Aghia Trias. We reached it by hiking North through the woods from the tip of the village.

Aghia Trias.

Approaching the monastery.

The little tree that could.

Their winch and net, used to haul up cargo and monks back in the day.

Front of the main building.

Secondary building.

The little cable car the residents use nowadays.

We then reached nearby Aghios Stefanos using the road.

Aghios Stefanos.

Inner courtyard.

Same courtyard, different angle.

So many candles burn here that they have a (holy) fume hood!

Outside the katholikon.

Garden.

Garden with the actual chapel of Saint Stefanos, if I recall correctly.

Afterwards, we took to the woods (more like the thorny, pant-intruding bushes) and made for Roussanou.

Entrance to Roussanou.

Inner courtyard, with part of the garden.

Overhanging structure, kind of like a covered balcony.

Hidden elevator, with older ladder.

Time-sharing of a furry implement.

Solicitation.

At that point, both Varlaam and Megalo Meteoro are pretty close. We reached Varlaam first - it is the most modern-looking of the monasteries we visited.

Varlaam and its access path.

Gosh darn, time to get rid of those pantaloons!

Making your way up, you can see their winch platform, which is still in use.

Plaza of sorts. You can see the modern treatment of the stone.

Inner hallway.

Feeling adventurous, we took a path through the woods to Megalo Meteoro. This turned out to be quite arduous - the path is narrow and steep, not very well-maintained, and thorny plants abound.

Megalo Meteoro from afar.

Main entryway. This place is pretty big, mega indeed.

The old wood workshop.

Stairwell leading up from the main alleyway.

Another angle into the ossuary.

Pot in the old kitchen.

Old table set.

Part of the sprawling structure of the monastery; it really is quite large.

Private courtyard.

Public courtyard with gardens and a water source.

Path to more museums.

Lastly, on our way back down to Kastraki (through the bushes again), we were able to photograph Aghios Nikolaos Anapafsas from afar.

Aghios Nikolaos Anapafsas.

Panorama taken that morning.

Greece 2010 - July 17th - On to Kalambaka!

2010-07-28T16:00:00.000-07:00

Our next goal was to go see the Meteora, which are on the main continent. We took a bus back from Nafplio to Athens, and stopped early at the metro. Metro to Syntagma Square, in front of the parliament. Then, the 024 bus to Bus Terminal B, where we hopped on a bus to Trikala. From there we took another bus to Kalambaka.

We did a bit of research for the next day, then went to bed. I have to say I was pretty stoked - this was what I had been waiting for.

Greece 2010 - July 16th - Fortress at Sea

2010-07-28T15:42:00.000-07:00

Next, we drove out to Monemvasia, which is described by the Lonely Planet as being "the Greek equivalent to France's Mont St-Michel." I'm afraid this didn't mean much to me until Laurence explained that it basically meant a big fortified city on a rock at sea.

Big is the rock, and impressive are the fortifications! In fact, the main fortifications are of comparable size, but the rock in Monemvasia is much bigger, and the stuff looks much older and timeworn.

The main square. Fortifications at the top of the rock are visible in the background.

A section of the main street.

Going up to the ramparts.

Church in the town.

The town has been mostly restored, but if you take the time to climb the stairs and go to the top of the rock, you can see beautiful ruins of a castle, cisterns, and more. There is also another mostly intact/restored church.

Ruins along the wall.

Church of Aghia Sophia, at the top of the hill.

Entrance to the church, from the side.

The background mountain is on the mainland.

Sun setting on the town.

Town from above.

The long way down. Very slippery.

The shorter (but deadlier) way down.

This door has seen better days.

That day was also an occasion to interact with the animal kingdom on multiple bases.

It is that hot.

They make Garfield proud.

Little guy lounging in the shade.

Goats on our way home. They are blocking the road, perhaps to protest something. Shortly after we snapped this picture, a pissed off shepherd dog attempted to take apart our Fiat.

Greece 2010 - July 15th - Olympia

2010-07-28T15:39:00.000-07:00

On the 15th, we drove to Olympia. Driving through the country we saw the beautiful village of Langadia, but unfortunately decided we'd take pictures on our way back, thinking we'd catch the sunset - which turned out not to be the case.

Arriving, we headed for the amazing Archaeological Museum of Olympia. It was inspiring to see tangible combat armor, as opposed to the goosed-up versions we see in movies.

Helmets, oldest on the left.

Greaves.

Western pediment of the Temple of Zeus.

Incredible detail.

We steeled ourselves and left the air-conditioned museum, heading for the site of ancient Olympia.

Philippeion.

Stadium. Along the right side you can see the judge's seats around the middle.

Fallen columns by the Temple of Zeus.

Possibly part of the Altar of Oaths.

Bath houses, I believe.

All told, it was pretty staggering to think of the sheer amount of historical "stuff" that had taken place at Olympia.

Greece 2010 - July 14th - Mani

2010-07-28T15:29:00.000-07:00

Driving to the Mani on the 14th, we stopped for a brief time in Sparti to check out the statue of Leonidas.

King Leonidas in butt-kicking regalia.

A short drive later, we wound up in the caves of Diros, which are quite something. You are taken on a boat ride over about 1.2km, and then walk about 300 further meters through the cave.

Caves of Diros.

Further south is beautiful Vathia, where people still live in a large fortification. (Their quarters are in the better-preserved portions.)

Vathia's impressive ruins.

Vathia.

Destroyed accomodations.

Juxtaposition of old and new.

Heading further south, we planned on hiking to the end of the land in order to scope out a lighthouse. After parking in the nearby town and undertaking a difficult hike and quasi-scramble to a tiny beacon, we decided that the experience wasn't anything like what was described in the Lonely Planet. Everything came to light a moment later as we realized I had taken a wrong turn, bringing us unknowingly to Porto Kagio instead of Kokkinogeia. As luck would have it Porto Kagio also has a trail leading out to the end of the land outcropping where a beacon/lightouse also stands. (Laurence spotted somebody who looked an awful lot like Tilda Swinton on the beach there.)

An hour later we were in the right place. This is the real lighthouse at the end of the Mani:

The end of the world.

Greece 2010 - July 13th - Mycenae and Epidavros

2010-07-28T15:10:00.000-07:00

Having secured a rental vehicle (Fiat Punto) part-way through the day, we headed off to Mycenae, not too far from Nafplio. It's a fairly large fortified city which was inhabited over multiple periods a good while back in pre-Roman times.

Lion gate at the entrance to the fortifications.

If I recall correctly, this is a grave circle near the front of the city.

Fortifications near the rear.

Treasury of Atreus, which sits well outside the city and is so large it was never buried by dirt and such.

Fortified city ruins seen from the bottom of the hill.

We then gunned it back through Nafplio to get to Epidavros before closing time. Epidavros is known for its theater and its asclepieion, which was a healing center in Classical times.

Entrance to the theater.

Ruins.

At this juncture I feel it is appropriate to digress slightly and mention what became a central component of our experience in Greece: the driving. The phenomenon is difficult to summarize, but the word "chaos" comes to mind.

The first thing you notice is that there are many two-wheeled vehicles, and they ride anywhere, everywhere, with the riders usually wearing no protection whatsoever - not even a helmet. They ride and park on sidewalks, between lanes, in parks, on cobblestone streets, you name it. Their scooters are so big (800+ cc) they even get on highways with them. As a corollary, traffic noise is extremely loud.

Cars also park anywhere and everywhere, even where the signs say otherwise. I took this picture on the second day of our trip, but had no clue of its predictive virtues.

No parking.

That sign is home-made, but even the official ones are most certainly ignored on a wide scale.

On a more general note, everything seems to be dominated by speed:

Respecting the speed limits will get you in an accident where you play the role of bowled-over obstacle. Driving through the Mani, we were passed while driving 100 km/h in a 50 km/h zone. My knuckles were white.
In North America, I feel rebellious when I drive through a stop sign in second gear. In Greece, a stop sign is an opportunity to get read-ended (especially since the signs are often placed in strange locations, i.e. immediately after exiting a highway, giving you very little time to decelerate). Matching traffic, I made it through many stop signs in fourth gear.
Driving over many hundreds of kilometers over 30+ hours in three in a half days, we found only three distinct traffic light locations.
Nowhere but in Greece will you spend so much time both well under and well above the speed limit. Well above because, as aforementioned, if you stay at the limit, you are a major hazard, both to yourself and to others; and well under the limit because many small cars are unable to reach the posted limits on the highway, which frequently reach 130 km/h. I drove flat out for miles on end in our little Punto.

Greece 2010 - July 12th - Hitting up the Pelopponese

2010-07-28T15:08:00.000-07:00

The next day was about reaching Nafplio, in the Pelopponese. All in all, the day was uneventful, except for a brief stint at Bus Terminal A, which the Lonely Planet describes as "not a good introduction to Athens".

Though Lau remained ever-confident, this was the low point of the trip for me - which is actually a good thing, because I guess it wasn't really that bad. There was much confusion stemming from the physical design of the place - buses parked everywhere in multiple lanes, signs which were difficult to interpret correctly, people milling about and sitting anywhere. Many Greek people were themselves unsure where to go or which bus to get on, which left little hope for tourists who didn't speak the language. In the end, a friendly junk salesman confirmed that we were in the right place, and we were whisked off in a high-tech bus to the Nafplio.

Greece 2010 - July 11th - Blazing Around Paros and Antiparos

2010-07-28T14:48:00.000-07:00

Wanting to ride around the island, knowing there were mountains to climb, we rented a 150cc ATV for the day. This made the day possible at all - we never could have covered as much distance, or tackled so much unfriendly terrain, had we opted for something smaller.

Paros has its own acropolis, Koukounaries, from the Mycenaean period. Before the sun got too killer, we hiked up there.

Near the top of the acropolis.

Settlements of some sort.

Helios might have been just waking up, but Eol was in full force.

After that, we rode around the island on dirt roads, enjoying the scenery. After a quick boat ride to Antiparos, we kept up the same, and found a small remote beach with strange rock formations.

The beach.

How we got there.

The water was very clear and much less salty than full-on sea water.

Spongy rock. Aero bars are evidently popular in this area of the country.

Greece 2010 - July 10th - Rest in Paros

2010-07-28T14:47:00.000-07:00

On the 10th, we left Naxos for Paros and rested for the rest of the day - sleep, laundry, beach, and so on. We only took one picture of the Parikia as we were coming in on the boat.

Parikia port, as seen from the ferry.

Greece 2010 - July 9th - Riding Around Naxos

2010-07-28T14:44:00.000-07:00

The 9th was our day to zoom around Naxos.

View from our hotel. Our room was on the roof of sorts.

We set out hunting for a dune buggy, but they were all rented, so we settled for a full/partial-convertible in the form of a Citroën Pluriel. (I'm not aware of any North-American equivalents to this type of vehicle - a knob in the roof essential slides the entire roof back into the trunk.)

Riding along the Northwestern coast to Apollonas, some ruins caught our attention.

Tower of Aghia.

Inside the tower.

Staircase to the tower.

Panoramic view from the road.

In Apollonas, there is a famous stone giant, which they surmise was never completed or moved because fissures would have prevented the statue from remaining in one piece.

Huge kouros from 7th century BC.

Small cat.

Naxos is pretty hilly and many villages are built on the slopes:

Village in the hills, which I think might be Koronos.

Before heading for Halki, we made a little detour by Mount Zeus to check out its cavern.

The path to the cavern. The bald mountain can be seen in the background.

Entrance to the cave.

Inside the cave.

Vegetation grows in here, but only where there is light.

Reaching Halki, a very old city, we visited the Kitron liquor factory. This was fascinating to the eyes, ears, and taste.

The sampling setup. The fruit at the front is the Kitron. The insides are fleshy and white. The liquor comes in different strengths up to 36%.

Old scale.

Jar for mixing stuff up.

The sights are beautiful in that little town.

Front of a house, with bougainvillier.

Front of a ceramics museum housing works by Katharina Bolesch, unfortunately closed at the time.

Grapes overflowing their boundaries.

Pathways around Halki.

Church outside Halki.

Greece 2010 - July 8th - Chora on Naxos

2010-07-25T08:16:00.000-07:00

The next morning, having fixed the camera, we were able to take pictures of Ios on the way out.

Cathedral of Ormos on Ios.

After a windy boat ride to Naxos, where even the huge ferry was rocked by the waves, we reached the port town on Naxos. It took us a while to check in because our hotel's front desk was closed during siesta time. After this, we just walked around the old town a bit, had a bit, and then hit up the Waffle House for some great ice cream on waffles.

Passageway.

Bougainvillier. Many massive examples to be found in Greece.

Lanterns slung in an underpass.

The width of a hallway. I'm not sure what warranted me to sport such a winning smile.

An old(er) house in the Kastro.

Temple of Apollo with a sunset, as seen from just outside the Kastro.

Greece 2010 - July 7th - Put-Putting Around Ios

2010-07-25T07:50:00.000-07:00

The next day was spent moseying around Ios, a beautiful island. It's too bad we only got to spend a day here because the pace of life and the look of the land really got us hooked.

A travel agent helped us map out the next few days of our trip and secure ferry tickets for the remainder of our time in the Cyclades, and then he dropped us off personally at a place belonging to one of his friends, the Liostasi spa/hotel. The place was awesome, very relaxing, with great food.

Liostasi pool.

Liostasi bar, with yours truly just getting up from an intensive bean-bag session.

Aforementioned bean bags.

Pool with the area where we ate.

Towards the mountain.

Then, we walked back down to the port area and rented another ATV. We rode around the island as the sun was setting, and witnessed one of the most beautiful landscapes of our trip - wind farms, stone walls outlining crops in the hills, rolling hills, a remote beach. (The 50cc engine gave us plenty of time to enjoy the view circa 10 km/h in the hills.) Unfortunately, at this point, the camera had given out with a lens mecanism error. We only managed to fix it the next day using percussion therapy, so we'll have to make do with the following shots of the city.

Hora cathedral with plaza.

Partial view of Ormos, the port city.

These little triangles are everywhere in Greece. It seems likely symbology is at play.

Greece 2010 - July 6th - Tearing Up Santorini on an ATV

2010-07-24T15:23:00.000-07:00

The next day, still in Santorini, we woke up to this quaint view:

That which can be seen at Blue Sky.

That day, we opted for personal freedom on the transportation front. This concretized in the form of an ATV rental from Zack, a man who looked, acted, spoke and generally emulated Sylvester Stallone in the role of Rocky Balboa. Unfortunately, since I lacked the presence of mind to digitally commemorate the occasion of our meeting with this man in audiovisual form, we must settle for this textual account of the adventure.

Naturally, immediately after securing a form of fast, open-air transportation in one of the countries with the highest motor vehicle death rate in the world (more on this later), we immediately headed to the nearest and largest wine tasting facility. Santo Wines, a pretty swanky place, actually represents all the wine producers of the island, which is mostly known for its whites.

Santo Wines.

Since I was designated driver by default, the task of ingesting three samples of wine under a beating sun after naught but a token breakfast befell Laurence, my girlfriend and longtime companion-in-arms. I did have a few sips however, and was duly impressed; I highly recommend the experience. The Vinsanto desert wine particularly stood out.

This put Laurence in a happy place:

The next best thing to a unicorn on film: mythical dual ponytails!!

We hit the beach up in Perissa, where the sand is actually made of little black rocks:

Perissa beach black sand.

The thermodynamically astute among you may surmise that in a country such as Greece, where the cosmic oven is always set to "MAXIMUM BROIL DEATH", the heat-absorbing qualities of such pebbles may tenderize the feet. Your postulate would be correct.

Dry, hot, blister-inducing.

Shortly afterwards, we followed a long dead end up into the hills to see some broken-down windmills. This was actually one of the highlights of our stay on the island for us, and it inspired us to go searching for less-travelled paths more often during the rest of the trip.

Old windmill with scenery.

Windmill.

A ruined axle.

Part of the mechanism.

A few more pictures that I like (many of the better pictures from this trip were taken by Lau):

Church bell.

Square hole with no peg in sight.

People live here, growing tomatoes.

Lau calls this picture "Donkey and the City."

Next, we headed to Red Beach, by Ancient Akrotiri. It gets its name from - you guessed it - red sand.

Busy Red Beach.

Red pebbles.

Stuff that pebbles are made of.

And finally, we caved in and joined the throngs of tourists in Ia for the sunset. Ia is the town which is most often seen on photos of Santorini.

Ia's houses, build right into the cliffs.

Backside of Ia with the sun setting down.

Yet another windmill.

Ia.

Architectural construct which does not have a North-American equivalent.

Obligatory sunset shot. The town is completely crowded.

Back in Fira, we had an excellent meal at Lithos and passed out for the evening back at the Blue Sky.

Fira at night (caldera side).

Greece 2010 - July 5th - Santorini, Caldera Cruise

2010-07-24T13:42:00.000-07:00

We reached Santorini very early in the morning, bleary-eyed, and took a bus from the port to the capital, Fira.

Fira.

We booked a tour of the caldera. After clambering down the hundreds of steps to the port of Fira (thinking what goes down... must come back up later), we boarded a cool, old wooden ship that rocked with the waves. Our first stop was on the central ash cone, Nea Kameni, which juts out in the middle of the caldera and is quickly reached by self-propelled seafaring implement.

Santorini caldera ash (Nea Kameni).

Santorini caldera ash.

The ash pit is pretty large and was the site of many eruptions. Little pamphlets explain which crater was made in which eruption, listing the spewed materials, thereby justifying the appearance of each respective cone. Quite interesting stuff really, considering it could be alternatively described as a big pile of rocks.

Afterwards, the boat moored near some hot springs by Palea Kameni (the old ash pile). We jumped off the boat into the sea and swam to the springs, swimming through the temperature gradient. This was amusing and confortable in the direction of increasing temperature, and... let's say, motivating, in the opposite direction.

Nea Kameni is on the left. The hot springs are just off the left of the picture, so you'll have to sort of imagine them.

A long food stop in Thirassia and a short stop in Ia later, we were back in Fira, with this to look forward to:

Stairs with a capital S.

Part way up.

This was actually quite amusing, and was but a teaser for all the other changes in elevation we'd have to tackle while in Greece. There are little rest spots along the way:

Rest in the shade.

It seems beasts of labor still very much have a home in Greece as well, what with all the wheel-unfriendly terrain about. Donkeys ferry people up and down the stairs for a small fee.

Donkeys!

Donkeys donkeying. I guess this is a practice run since nobody is sitting on them.

This is what it looks like as you reach Fira.

Now the picture above denotes a count of approximately 600 steps to the top of Fira, but that's a figure that is difficult to drop into comparative context. The steps are quite deep (well over a meter, sometimes two) and the ground between the steps angles up, so that when you reach the next step you've actually increased your potential energy by the height of another actual step or two by walking quasi-horizontally.

Greece 2010 - July 4th - Athens

2010-07-24T12:25:00.000-07:00

August 4th was our day to visit Athens - we played hot-dog to the acropolis' stifling tourist oven.

Propylon of the acropolis.

Erechtheion.

Parthenon. It's impossible to get a shot of this without a thousand people in front.

It's pretty impressive to see these things just hanging out in the middle of town, especially since there are virtually no high-rise buildings in Athens. I tried to dredge up a comparison or an analogy between the Acropolis and the cross on top of Mount Royal, but I seem to be lacking the proper mathematical operators.

Athens behind the Odeon of Herodes Atticus.

The Odeon of Herodes Atticus from a little further back.

As you can see, they were setting up for that evening's concert. That place is like ~1850 years old (with some restoration) and is still very much in active use.

There's another theater on the same slope, but it's been decommissioned.

Theater of Dionysus Eleuthereus.

Then we wandered down the hill and saw some more ruins and old buildings.

I believe this to be the church of Agiou Apostoloi, but I'm not positive.

After much {p|r}anting and profuse sweating, we found some shade in the National Garden. It's a beautiful, public place. At the moment, however, its most important attribute may have been the fact that the dudes out front sold ice-cold water.

National Gardens.

The day ended with us packing our bags and getting on the subway in the hopes of hitting up the port of Piraeus for some overnight ferry action. However, as luck would have it, gremlins had eaten the end of the subway line (or at least that's what I made out from the explanation the driver gave over the PA system in Greek), and we got dumped topside at the intersection of Not The Port and Not Much Time Left. We employed the services of a Taxi Warrior in order to rectify the situation, and rectify he did, using his trusty gas pedal, a deep knowledge of honk-sparring, and some fanciful gesturing with his left arm out the driver's window. It all culminated with the cutting off of literally 20+ cars in a left-turn lane, a burst of acceleration down the quay, and dropoff at the boat itself with entire seconds to spare.

As the boat sailed to Santorini, we tried to sleep. Truth be told, that was one of my worst nights - the seats reclined about five degrees (so it was difficult to sleep while sitting), the armrests didn't budge (so it was difficult to sleep across multiple seats), and the carpet doubled as an acarian farm (so sleeping on the ground caused sneezing fits). (This was an Anek Lines boat - the Blue Star Ferries ones we took later on were much nicer. Live and learn.)

Greece 2010 - July 2nd/3rd - To Athens!

2010-07-24T09:30:00.000-07:00

This summer, my girlfriend spent a month digging at an archaeological site near Asprovalta, in northern Greece. I took time off work to join up with her after her stint there, and we spent about three weeks traipsing around the country generally abusing our camera, interacting with the public-use felines, reaching relativistic speeds in our rental vehicles and, best of all, not getting sick.

I mean to document the experience a posteriori here, both as a personal log and as a way to share the memories. It was not done during the trip for lack of the unnamed mojo resulting from the convolution of time, energy and the availability of internet access. Now that I am at home for a last week off, said mojo is available in larger nuggets; here are the fruits of its investment.

To begin, a random picture:

An ossuary in Grand Meteora.

Paper YZF-R1 (2003-2004)

2010-06-18T20:54:00.000-07:00

Origami being a hobby I adopted really young, when the link to this paper YZF-R1 showed up on Slashdot back in 2003, I had to investigate. I usually stick to models requiring folding only (i.e. no scissors or glue), but the detail in this model was so interesting I had to build it.

The pattern is still available from Yamaha's website. It took approximately 80 hours
to cut, fold and glue, spread out over the course of approximately three months at the start of 2004.

The observant will note that the cycle is missing its rear right flasher. It was actually inhaled by accident while holding it up close to try and push out a kink. (Don't ask.) The fresh glue was difficult on my digestive system, even though the manufacturer claimed the glue was non-toxic. My vocal complaining prompted my chemical engineering friend to explain that "non-toxic just means it's not going to actively try to harm you, dude, it doesn't mean it's going to be fun to digest."

The above pictures are from 2004, when I finished building the bike. Six years later, I still have it, and it has proven both a blessing and a curse: I'm glad to have built it, but now I'm stuck with a new trinket, so to speak. As with most things, it was about the journey more than the destination, and now I'm wary of forgetting about the former if I dispose of the latter.

Lessons learned:

When you set out to build something fragile like this, you really need to know up front where you're going to store it afterwards so it doesn't deteriorate. In this case, I think a shelf behind a glass window would have been perfect to avoid physical damage and dust. (The dust is now virtually impossible to get off.)
Craft glue does not hold up forever. After a few years, the parts that stick out will start sagging, even if the model is not manipulated often. Be prepared to either endure or touch up.

it begins

2010-06-15T21:26:00.000-07:00

[Wow, what a badass case of writer's block - over ten years.]

Once upon a time, I had a blog of sorts on a university server. I wrote nonsense about my student life, and shared a few projects. One day shortly after hitting a thousand hits, I oversaw this dude I'd never met before running one of my OpenGL programs on a public terminal. It really drove home the notion that my stuff was "out there" for anyone to read or download.

Strangely, I truly felt as though this was a massive intrusion of privacy. I wrote a final post detailing that very event, and that was it - the site never got updated again, eventually being eaten up by the maintenance langoliers.

What gives? In retrospect, I realized that I was using the web more as a way of writing home than as an open book which anybody could read. Typing in a URL is about as difficult as reading a street sign, and your content is just about as public. Quite a simple insight, but as the saying goes, sometimes it's difficult to see the forest for the trees.

So, here we are. Since my last post, Napster has died, the Matrix has Reloaded, Katrina has destroyed, Barack has been elected, and Michael Jackson has left us.

As for me, I plan to share projects and thoughts. Great success!