Posts In: General News

June 7, 2014

It's cheating, sure, but can give a lovely, artistic look. The eye really does love those gradients...

Rounded Box Projection

February 22, 2014

Suppose you want a nice rounded box mesh. You know how to create a mesh for a tesselated box. You know how to get a nice sphere mesh from a tesselated box mesh - you just project the box's points to a sphere:

p' = normalize(p)

What about a rounded box? How can we take a tessellated box mesh and project it nicely to a rounded box? For a box spanning [-1, 1], with a rounding radius of r, you simply:

p_box = clamp(p, -vec3(1 - r), vec3(1 - r))
p' = p_box + r * normalize(p - p_box)

Clamp the point to a smaller box, project the remainder to a sphere, reconstruct. Note that, while I say 'vec3' here, it's good for 2D as well (or however many Ds you need).

I write this down both for myself, and since I didn't find anything by searching (yes, I'm a bit embarrassed that I tried searching this first...)

Gamma-Correct

November 5, 2013

I guess I'm prepared to admit that, after finally getting everything tweaked properly...linear lighting does look darn good.

Kind of amazing how what amounts to little more than a sqrt in the lighting falloff is...so influential to the eye's perception of correctness..!

NOTE: Aberration is too aggressive.

Runtime Reflection II

October 22, 2013

A much more intuitive way to visualize the data. And appropriate, considering the game's context ð

Area of "star" is proportional to memory footprint. The connectivity is reflective of the structure of the data. Cool stuff...someday I'll do the same with the code rather than just the data. That'll be fantastic.

In-Engine Data Map

In-Engine Data Map (Closeup)

Edit: and a few more just for show ð This is a pretty deep visualization of a ship, going all the way down to the attached hardpoints (thrusters, weapons, power generator) and most of the data therein. Amazing how beautiful and structured the data is.

Runtime Reflection

October 9, 2013

Hard not to be proud of a c++ engine that lets you look inside of it with no boilerplate code ð

Runtime Reflection in the LT Engine (on the right)

Really a shame that I didn't post about any of the recent graphical improvements ð Gotta hop back on the bandwagon at some point though!

Procedural Nebulae V

May 15, 2013

Naturally, I can't leave well enough alone! Â Attempt IV was pretty cool, but it obviously lacked volume. Â No surprises there: it was 2D. Â Here's my first attempt at volumetric light inside of the same type of nebula as shown in the previous post. Â I'm sure it will get better over time, but already you can notice a much better sense of volume, softness/cloudiness, and of light transport. Â Light is correctly modeled using emissitivity and absorption as it passes through the nebula. I'd say this is a pretty good amount of nebula-related progress for 2 days!!

Procedural Volumetric Nebula

Procedural Volumetric Nebula

Procedural Volumetric Nebula

This method is about as expensive as the current LT nebulae...but it looks way better...so I think it's safe to say this will be replacing them soon ð I am very happy with these, and I think I would quite enjoy seeing them in the background! Â All the parameters - softness, brightness, feature size, absorption, wavelength-dependence of scattering, etc. are all easily-tweakable to get a lot of different styles.

Procedural Volumetric Clouds

Procedural Volumetric Clouds

Procedural Nebulae IV

May 14, 2013

Tonight, I feel like I have closed a chapter in my life. Â For almost three years, I have been trying, on and off, to understand nebulae. Â In particular, I've been trying to generate them procedurally. Â If you look back over the log, you'll find several attempts:

Arguably, I've been getting better over the years. Â As my understanding of math improves, so does my ability to craft these lovely things. Â Although 2013's nebulae are significantly better than the rest (and, arguably, some of the better procedural nebulae out there on the web), let's face it, they still don't look like nebulae. Â But tonight, tonight I think that I have discovered the secret of nebulae. Â After three years, I finally feel that I understand these things. Â And I'm proud to say that my nebulae...finally look like nebulae.

Procedural Nebulae, Three Years Later

In yet another attempt to drive the lesson of simplicity into my mind, the universe has shown me that nebulae - in my opinion, some of the mostÂ gorgeousÂ and complex objects out there - are actually simple. The image above was produced by 31 lines of code, which is far, far less than any of my previous attempts. The code that actually defines the nebulae itself is about 20 lines. Dead simple.

ð

How to Write a WAV File in c++

March 21, 2013

It's surprisingly hard to find clean and simple code to do this, but it's surprisingly easy to do. Here it is, if anyone has ever wanted to write their own sound files in c++.

http://ltheory.com/blog/writeWAV.txt

My code formatting in this blog is horrible, hence linking it as a separate file. Now all you do is call writeWAVData like this:

writeWAVData("mySound.wav", mySampleBuffer, mySampleBufferSize, 44100, 1);

Which would write a 44.1khz mono wav ("CD quality"). mySampleBuffer should be an array of signed shorts for 16-bit sound, floats for 32-bit, unsigned chars for 8-bit. Since the function is templatized, it automatically detects the format and takes care of the relevant fields in the WAV header.

Oh, and this only works on a little-endian machine, since WAV is expected to be little...but that probably doesn't matter to anyone these days, right?

Enjoy...I guess?

Procedural Sound Synthesis

March 18, 2013

It had to happen sooner or later...audio synthesis (not composition, but actual synthesis) is one of the only realms of procedural generation that I have yet to touch...well, at least, that was true yesterday. But not anymore! ð

Yesterday I finally indulged myself in trying out audio synthesis. I read a few basic materials on the subject, but, much to my surprise, audio synthesis is incredibly simple! It seems like the audio people really enjoy making up their own fancy terminology for everything, but, honestly, it's dead simple: audio synthesis is the study of scalar functions of one variable. Period. That's literally all there is to it: a sound wave is f(t), nothing more, nothing less. Wow! That's great, because I'm already pretty darn familiar with Mr. f(t) from my work in other fields of procedural generation. Is it coincidence that it always comes back to pure math? I think not ð

Here are a few sound effects that represent my first-ever endeavors into audio synthesis. I know, they're terrible, but they were made from scratch by someone who has only known how to synthesize audio for less than 24 hours, so maybe that makes them a little better. In the fancy audio terms, I guess you could say that I used "additive synthesis," combined with "subtractive synthesis," and even a little "frequency modulation" on top of that. But really, all I did was write some math. Sums of sines ("additive synthesis")...multiplications of those sums ("subtractive synthesis")...domain distortions ("frequency modulation"). All the usual procedural tricks. Heck, I even did the equivalent of fractal noise! Turns out it works just as well in audio. Those magical fractals ð

Well, here they are. Someday they'll get better, but certainly not in time to have procedural sound effects for LT1. Oh well. Maybe next time.

Sweet Profiler

February 21, 2013

Spent a good chunk of today upgrading the in-engine profiler, which had gotten so old andÂ obsoleteÂ that I never really used it anymore, and preferred external tools for profiling. Â Well, that needed to change, because in-engine profiling is by far the most convenient. Â It also gave me a nice opportunity to break in my new interface system. Â Thanks to this week's overhaul of the interface engine, I was able to cook up what I think is a great-looking profiler with almost not effort!

More important than the looks, however, is the accuracy. Â I dramatically improved the accuracy, and now it is giving me what seem to be very good results! Â This will be invaluable as I continue to add complexity to the game. Â Man, this thing makes the performance optimizer in me so excited ð

Shiny New In-Engine Profiler!