# Tasaq

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1. ## Objects distribution within concave polygon

Finally I found something satisfying, Particle Swarm Optimisation was good for my problem. I used the same fitness function as I used for GA but PSO was much faster and gave a little bit better solutions.
2. ## Objects distribution within concave polygon

This sounds like a nice idea. So do you think something like combining GA with gradien descent would be a good way to do it? I also found something like this: https://www.youtube.com/watch?v=HQ41szO1AMc   The first part of the video (0:00 - 0:25) shows something I need. The points are distributed in optimum way and can be easily aligned afterwards (even manually). I have no idea what was used here, it looks like some kind of coverage optimization using independent inteligent agents?
3. ## Objects distribution within concave polygon

So, first of all I am under NDA, so I need use analogical examples of my problem. Mainly I am looking for algorithms that can help me find results for my problem, so this is mostly theoretical question.   My input would be concave simple polygon (a list of points in cw or ccw order) that contains holes (stored as a list of list of points). Alternatively, I can triangulate that polygon and input this as a list of triangles. They mostly would be a simple shape where neighbouring segments are in right angle (I attached some example cases). Sometimes input might contain segments under irregular angles.   Having this region defined, I want to distribute objects within that shape. The number of objects doesn't need to be constant, but needs to be in given range (for instance at least 2 must be placed, but no more than 20). Each objects have some properties defined and influence each other.   Another problem is that they need to be placed in aesthetic way, to give you a real life idea I don't want to end up with something like this. But I might adjust the locations as a post process, so this is less important right now.   As the output I would need the list of points.   What I can provide for the algorithm are learning sets and evaluation method which says how good the output is.   Some examples - wireless signal enhancers placement in a building, monster placement in dungeon crawler game where each monster has different power, hp etc., chests/pick-ups of different value positioning in the game, maybe heat detectors (or any other detector) distribution in a room, surveillance cameras distribution in a room (so we want to place them in the way they cover the most space with least devices used).   The thing I already tried is an expanding grid of points, but it gave bad results. I also tried genetic algorithms, but they took to long and gave very random looking point distribution, the results were almost perfect in terms of numbers though. So I am looking for some kind of method that can adapt points to shape of the room and give as good results as GA. I was also thinking about neural networks, but the only ones I was working with were outputing true/false value and I don't know if they can create a list of points.   So does any other optimization agorithm/concept comes to your mind? I also didn't work with any fuzzy logics yet, I even have no idea how they work, I am just aware of their existance, is this something worth investigating in this case?
4. ## Terrain LOD tessellation cracks

Are you using hardware tessellation? If so, can you share the code?
5. ## Tegra 4 Extensions

Hi,   I am ashamed to ask such question, but I am lost in search. I am creating an Tegra 4 application that is in need of render target with pixel format that will store, for instance, logarithmic luminance, something like R16_float. AFAIK Tegra 4 supports such formats, but they are not available in standard OpenGL ES 2.0, only through extensions. How do I create such texture with GLES20.glTexImage2D? I know how to use glTexImage2D, but I have no idea how to include those extensions in Java (I am not using NDK).   I would appreciate any help, all I could find on the net was how to get supported extensions as a string, not how to use them.
6. ## Are you a gamer?

I play some games. Or should I say, re-play, since I prefer games from late 90's From modern games I play Smite and some games I find cool (I am very demanding gamer). But I must say I mostly spent my time coding than playing. Sometimes when friends show me a gameplay of new game I am like "WOW, they got nice shading". Same thing happens when I play, I am like "wow, what a nice material on that trash can..." or "this shadow artifacts are strange, wonder what's causing them" and at the same time I die or crash or whatever   Oh, and I once heard something like that: "I am not playing games, I am checking what kind of technology competition has" :)
7. ## OpenGL Real-time Ray Tracer in GLSL

I think you did it in a similar way as I did mine.   I don't see part for triangle intersection? Does that mean the walls in your video are just enormous speheres?   More reasonable approach for ray tracing in real-time is to use either OpenCL or CUDA, they are much more flexible than fragment shaders. As you experienced you got 10 fps for scene with 10(?) spheres and 2 lights. I don't want to discourage you in any way, but imagine you want to render scene with, for instance, 5000 triangles For that you are bound to use acceleration structures, and they might be tough to implement with GPGPU.   If you want to follow the path of writing real-time ray tracers, you can try implementing geometry shader ray tracing: http://ar.in.tum.de/pub/ralovich2010rsigs/ralovich2010rsigs.pdf   Note that this technique is slower than fragment shader method (ready article's results section for details).
8. ## OpenGL Real-time Ray Tracer in GLSL

If you have Nvidia GPU why don't you try OptiX?   link here: https://developer.nvidia.com/optix
9. ## OpenGL Real-time Ray Tracer in GLSL

I don't quite get how you did this :) In my real-time ray tracer I used compute shader instead of fragment. I am using this to experiment with new rendering technique, so it's not very sophisticated, it got texturing, reflections, shadows and classic Phong, and it's only based on speheres. I can get 60fps in 720p with one large textured sphere and dozen other flying around. All spheres are reflective (5 bounces). What I did is I just passed arrays of structures with lights and sphere's to the shader and did everything in one huge (aka uber) shader. It required to implement stack inside shader and other nifty things.   Could you describe step by step what are you doing? Could you provide us with more details, like resolution, your hardware etc.?   On a side note, ray tracing is hardcore to implement in real-time and low fps is predictable, "I'm new in Computer Graphics" and real-time ray tracing doesn't mix if you ask me.
10. ## [GLSL] NVIDIA vs ATI shader problem

Depending on the version, GLSL requires you to put the f suffix on there. nVidia's GLSL compiler deliberately accepts invalid code, whereas AMD's strictly follows the specification. This is a good way for nVidia to use us developers as a marketing/FUD weapon, spreading rumours that AMD has bugs...   Seeing that GLSL code is compiled by your graphics driver, which may or may not be different to your user's driver, it's a good idea to run your code through an external tool to ensure it's valid, such as ShaderAnalyzer, glsl-optimizer, the reference compiler, etc...     It was during the time I used shaders for the very first time and 'I had no idea what I was doing' :). Back then I was using shader designer btw.
11. ## [GLSL] NVIDIA vs ATI shader problem

This is very annoying thing when it comes to shaders :\ I remeber in my early days when I tested my application on Nvidia card everything was ok, and I had problems with AMD. What solved my problems was changing doubles to floats (i.e. changing 0.0 to 0.0f).
12. ## My new scene-river zone

I like how the water looks very much, but I would reduce it's simulation speed because it looks super fast for me :)
13. ## c# game

I need to quote and extend what L. Spiro wrote, since it is so essential. This is ultimate skill for a programmer, if you can't find information you require, sorry, but you won't go far. If you truly can't find anything, then you need to try do it yourself. If you fail, then you ask. If you won't figure something out on your own, you won't learn or quickly forget. And it is very important to be POLITE, always. Btw, how did that guy get 772 rep? ;o
14. ## How to debug an fx file

Be a little bit more specific, what kind of error do you get? Which version of DirectX, 9 or newer?   For visual studio ultimate 2013, alt+f5 will start application in diagnstic mode, there you press print screen (not sure if was prt sc), close application and you get a lot of stuff. You either need to go through even list to find draw call you want to debug or pick pixel and check it's history.   Note: What I wrote here is from memory, I mostly use built in profiler instinctively :) For more accurate information, check this link: http://msdn.microsoft.com/en-us/library/hh873207.aspx#fbid=cfoh58W0Z1l