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1  Games Center / Showcase / Re: VERBAL - the fast-paced thinking word game on: 2015-04-26 22:27:42
I don't know... I have never got an android emulator working myself Sad
2  Discussions / Miscellaneous Topics / Re: What I did today on: 2015-04-11 22:49:40
Blogged. Because I'm sad.
3  Discussions / Miscellaneous Topics / Re: What I did today on: 2015-04-08 20:23:49
A giftastic post from me... I learned how to make animated GIFs in GIMP and made my first one, showing how my optical simulator builds up a diffraction pattern in a series of iterations (in this case, the pattern is the diffraction pattern formed by a newtonian telescope):

Click to Play
4  Game Development / Shared Code / Re: Curve fitting on: 2015-04-02 10:52:42
I'm really not keen on learning a bunch of fancy maths just to fit a curve. Fourier transforms are more interesting for the more general problem of transforming a telescope aperture to its Fraunhofer diffraction pattern, but ray tracing works fine for now.

Regarding the curve fitting problem that leaves me with... Firstly my curve fitting algo is not a general solution, it glitches severely for samples with a y value close to zero (amplitude errors up to 95%). I solved that problem by taking four samples and picking the pair of consecutive values furthest from zero. Changing from 12 samples per pixel to 4 samples per pixel obviously helps memory and reduces the size of my innermost loop by a factor of 3.

Secondly, the process needs to be quick enough for processing an image plane of 300x300 pixels. I find I can get a max error of ~0.04% in two seconds with just over 200 iterations per pixel. Two seconds is fast enough, given that the ray tracing itself is going to take between five minutes and five hours depending on the aperture being calculated.

I updated the pastebin with the small changes I've made to solve the glitchouts.

Avg Error by curve fitting        : 0.00116%
Avg Error by rough curve sampling : 1.13904%
Avg Error by fine curve sampling  : 0.28740%

Max Error by curve fitting        : 0.03782%
Max Error by rough curve sampling : 3.40740%
Max Error by fine curve sampling  : 0.85551%

Steps for curve fitting           : 221
Millis taken for ccd              : 1994.1
Millis taken for program          : 2166.0
5  Game Development / Shared Code / Re: Curve fitting on: 2015-03-31 21:56:41
Thanks, I will have a look at these. I would like to understand FT, but I would need to understand it to a level where I knew the equations represent a physical reality. With ray tracing and simple addition of wavefronts, I know what I am doing because I avoid the mathematical sophistication. Whereas with FT, I can google some code and use it, but i can't check my own work yet.

For example, with my program I can compare the Airy disc of my current telescope to a larger one I am thinking of buying:

With the curve fitting however, all I am trying to do is get back to a sine curve from a minimum number of samples with least effort. At the moment, I am just getting amplitude by brute force by calculating lots of samples.
6  Game Development / Shared Code / Re: Curve fitting on: 2015-03-31 21:18:25
Yes, I am exactly emulating a fourier transform. I struggle to understand the FT maths but I do understand the physics, so I am building a simulation instead.
7  Game Development / Shared Code / Curve fitting on: 2015-03-31 11:03:34
I am doing some experiments with optics and ray tracing. This involves calculating the amplitude at various points across the image plane, given a known frequency and an unknown phase and amplitude. Currently I just generate a dozen points on the curve and pick the one with the highest amplitude, but not only is that lazy and inaccurate, it is also very expensive to generate a dozen samples per pixel of the image plane (it involves iterating over hundreds of thousands of samples of the source wavefront).

it would be better to generate two or three samples and then use some kind of curve fitting to get the amplitude. There is probably an algebraic method, but that would involve maths.

So here is my first stab at a curve fitting algorithm. It involves 200 iterations to get a curve match with an error of ~0.01%, although the method occasionally glitches out with an error of 1%.


Edit: Latest:

When I run it I get output like this:

Error by curve fitting        : 0.00263
Error by rough curve sampling : 1.17135
Error by fine curve sampling  : 0.28717
8  Discussions / Miscellaneous Topics / Re: What I did today on: 2015-03-28 23:21:40
Carried on playing with Fraunhofer diffraction patterns.

9  Discussions / Miscellaneous Topics / Re: What I did today on: 2015-03-27 10:21:10
I can now calculate the point spread function (Fraunhofer diffraction) for arbitrary telescope apertures using ray tracing.
10  Discussions / Miscellaneous Topics / Re: What I did today on: 2015-03-08 15:12:49
Remember those little white dots that represented stars yesterday? I turned them into something a little more meaningful.

accidently messed up the generation and made a really huge star (in the real deal you have a better chance of winning the lotto then finding a star this size):

Super super tiny red dwarf:

An upper-sequence-minigiant star, but around as hot as ours irl.

A blue giant:

Note the positions, they are real stars in the real server-side universe (just displayed on the client)

+1 Appreciation for the seeming astronomical accuracy. Are the star type distributions based on galaxy structure (e.g. hot O,b B stars in the spiral arms, in clusters, older stars in the core, etc)?
11  Discussions / Miscellaneous Topics / Re: What I did today on: 2015-03-07 12:17:17
I wrote a simple simulator for dew heater circuits to optimize my designs for dew heaters for my camera lenses.
12  Discussions / General Discussions / Re: GDC 2015 - various stuff on: 2015-03-05 20:24:53
That kite demo is just wrongg. A kite free of its line would fall to the ground. Smiley
13  Discussions / General Discussions / Re: The Khronos Group announces "Vulkan": the successor to OpenGL on: 2015-03-05 11:51:50
The underdog (AMD) always favors open standards, while the market leader (Nvidia) always prefers push their closed solutions. FreeSynch versus GSynch is another example.
14  Game Development / Newbie & Debugging Questions / Re: Libgdx How to task/thread/wait the start of the screen. on: 2015-03-04 18:11:10
An easy solution would be to throw away the first frame (just render a black screen), and start everything running on the second frame.
15  Discussions / General Discussions / Re: The Khronos Group announces "Vulkan": the successor to OpenGL on: 2015-03-04 15:27:18
Only 3? What about Imagination, ARM... This thing is supposed to run on all platforms, isn't it?
16  Discussions / General Discussions / Re: The Khronos Group announces "Vulkan": the successor to OpenGL on: 2015-03-04 11:22:11
Well done, AMD.
17  Discussions / Miscellaneous Topics / Re: What I did today on: 2015-03-01 00:36:10
Hmmmm. It's not evolution if you have a goal.
18  Discussions / Miscellaneous Topics / Re: What I did today on: 2015-02-27 21:16:31
Opiop, you ARE a real game developer.

On the subject of design documents, my worst work in my enterprise environment has always started with a fat design document, maybe even written by me. The more effort spent on the design document, the worse the end result.

My best work has been seat-of-pants stuff where I code in a frenzy of intuition, racing to finish the project before management notice and stops me.
19  Games Center / nK Game Competition - 2015 / Re: Java4K framework WIP / discussion on: 2015-02-26 17:22:10
This looks promising!
20  Game Development / Newbie & Debugging Questions / Re: java.awt.Point class in Android on: 2015-02-21 23:41:38
An Android app needs java.awt.Point like a fish needs a bicycle. There is no way to get AWT running on Android. If there is no way you can get rid of this class from the code snippet you are using, then you are simply using the wrong snippet of code.
21  Discussions / General Discussions / Re: Motivation on: 2015-02-20 22:18:32
Most IDEs support:

//to-do: note to self

I should use the feature more often...

What motivates me? A shiny new thing.
22  Discussions / General Discussions / Re: Does Java have 'pointers on: 2015-02-20 20:40:17
Java has NullPointerExceptions, so it must have pointers Smiley
23  Discussions / General Discussions / Re: Too complicated? on: 2015-02-18 16:11:30
Is chess too complicated? And do your target players want chess complexity?
24  Discussions / Miscellaneous Topics / Re: What I did today on: 2015-02-16 21:53:55
Thinking of changing my nick to "entity". Or "sprite".
25  Games Center / WIP games, tools & toy projects / Re: Headline Benchmark on: 2015-02-16 11:34:29
Hey... I've passed 300 downloads for the desktop version:

Windows-64: 202 downloads
Windows-32: 53 downloads
Linux-64: 37 downloads (it's catching up on Win-32!)
Linux-32: 17 downloads

I'm up to 160+ downloads for the android version :-)
26  Discussions / General Discussions / Re: What's your day job? on: 2015-02-16 11:28:55
I provide second-line support to developers using various enterprise APIs. I manage schemas and datamodels and build toolsets for these, and I write user guides.
27  Discussions / Miscellaneous Topics / Re: What I did today on: 2015-02-13 11:14:32
The big bucks are in soul draining enterprise application backends. Emo

 Huh I love my enterprise backend work!
28  Discussions / Miscellaneous Topics / Re: What I did today on: 2015-02-10 21:34:47
Got WebGL and OBJ loading working on my website. Nothing to demo yet - I just got some googled code working.
29  Discussions / Miscellaneous Topics / Re: Bit pissed off at uk school system... on: 2015-02-10 19:09:47
My daughter is a UK teacher, I hear all sorts of horror stories.
30  Discussions / General Discussions / Re: What does this return for you? on: 2015-02-10 11:14:07
The GPU names on my benchmark site are from GL11.glGetString(GL11.GL_RENDERER):

What drives me absolutely nuts is AMD's naming scheme: "AMD Radeon R9 200 Series" could be a 280, 285, 280X, 290, 290X... It makes my AMD results basically useless.
Pages: [1] 2 3 ... 28
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How to: JGO Wiki
by Mac70
2015-02-17 20:56:16

2D Dynamic Lighting
by ThePixelPony
2015-01-01 20:25:42

How do I start Java Game Development?
by gouessej
2014-12-27 19:41:21

Resources for WIP games
by kpars
2014-12-18 10:26:14

Understanding relations between setOrigin, setScale and setPosition in libGdx
by mbabuskov
2014-10-09 22:35:00

Definite guide to supporting multiple device resolutions on Android (2014)
by mbabuskov
2014-10-02 22:36:02

List of Learning Resources
by Longor1996
2014-08-16 10:40:00

List of Learning Resources
by SilverTiger
2014-08-05 19:33:27 is not responsible for the content posted by its members, including references to external websites, and other references that may or may not have a relation with our primarily gaming and game production oriented community. inquiries and complaints can be sent via email to the info‑account of the company managing the website of java‑
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