particles

Projecting a 3d sphere into a 2d circle on the screen

What are some rasterization algorithms that can just project a 3d sphere into a pixel grid? I want to avoid ray casting. Essentially, given a 3d coordinate and a radius, is there a quick way to just create a 2d circle/ellipse on a pixel grid? For example: circle at (2,2,2) with radius 4 gets projected to five pixels: p1(2,0)p2(0,1) p3...

XML Schema - getting around unique tag constraint

I have to make a schema for an XML format that's already being used. The existing XML is being generated already by a different program, and it sounds like it would be difficult to track down all the places that would need to be changed in order to use a more regular XML format. Here's an example similar to our XML structure: <data> ...

How can I create a random simulation?

I've been playing this flash game and after I'd gotten over the initial ('lol, fire') reaction I started to wonder how I could replicate this contact-mutate behaviour in programming. I guess it's a little like the honeypot xkcd. I was thinking of starting with a scenario where particles deflect off each other and the containing walls. T...

Particle System Design ?

Hello, I'm designing my own particle System engine, this is for learning purposes, I don't really want to use an existing engine. Right now I generated beautiful particles, but I want to layout the engine to make it easier to work with them. I have been thinking on a Class "Particle System", that class would contain the following refe...

Particle stream should be the same length regardless of emitter speed

Hi, I'm writing a particle system for our student game, and I've run into a bit of a snag. I want to improve the effect on the ships' rockets, but I can't seem to figure out how. Here's how the effect looks on a stationary ship: And here's how it looks on a moving ship: I want the flames to be the same length consistently. Here's...

How to render non trivial particles in OpenGL.

I have a particle system where the positions and various properties are stored in a vertex buffer object. The values are continuously updated by a CUDA kernel. Presently I am just rendering them using GL_POINTS as flat circles. What I am interested in is rendering these particles are more involved things like 3d animated bird models f...

In Java Monkey Engine, can you treat a single particle like any other object in the scene graph?

Using the in house particle system for Java Monkey Engine, you generally create a sort of emitter which is a factory that spews out a bunch of particles. Are these particles part of the scenegraph and is there any way to get a handle on an individual particle? The particle system for JME2 isn't very well documented and any insights int...

opengl modelling rocket flame and vapour trails with particles

Does anyone have any guidance for coding an approximation for the particle stream coming out of a jet engine (with afterburner) in opengl using particles drawing using vertex buffers / 4f color buffers? I believe there are two aspects to this problem: The colour of the light as particles exit the jet engine as a function of temperatur...

iPhone. Particle system performance

I try to draw rain and snow as particle system using Core Graphics. In simulator rendering proceeded fine but when I run my app on real device rendering is slow down. So, advise me please approaches to increase particle system drawing performance on iPhone. May be I should use OpenGL for this or CoreAnimation? ...

Getting started with particle system in 2d

I would like to get started with particle systems in 2d. But I really don't know where to get started. ...

Fastest Strategy for Drawing Flash Particles

I am wondering what the fastest approach might be for using Flash/AS3 to render a 2D point plot (sonar lofargram) ; basically screens full of tiny 2D dots using Flash as fast as possible. Any suggestions on where to start? Is Flash capable of displaying 10's of thousands of 2D points (or more) with an acceptable fps? ...

How to create Particles structure from text in AS3?

I want to take any Text sting and form from it text formed by particles in actionscript 3 (In flash \ flex) I see I need some lib for this. but all libs Ive seen do not have such functionalyty by default... So I want to get something like this So Is there any sych lib? or way of doing it with some lib? It should be Free and Opens...

particle system: particle generation

Hello: I have a system that generates particles from sources and updates their positions. Currently, I have written a program in OpenGL which calls my GenerateParticles(...) and UpdateParticles(...) and displays my output. One functionality that I would like my system to have is being able to generate n particles per second. In my Gener...

uniform generation of points on 3D box

Hello: I would like to generate random points on a 3D box defined by its (minx, miny, minz) and (maxx, maxy, maxz) corners. I was thinking of generating a random point inside of the box and then somehow projecting it onto one of the box sides. However, I don't have explicit plane information for the box sides and this seems like it will...

uniform generation of 3D points on cylinder/cone

Hello: I wish to randomly and uniformly generate points on a cylinder and a cone (separately). The cylinder is defined by its center, its radius and height. Same specifications for the cone. I am able to get the bounding box for each shape so I was thinking of generating points within the bounding box. However, I'm not sure how to proje...

how to create a particle system on iphone and retain the created particles?

Hi all, I need to create a particle system and retain the created particles. I need to shake / move the created particles with the iphone accelerometer. Also, the number of particles needs to be very high (I need to show sand!). I do not have any OpenGLES programming experience. After initial search, I found Cocos2D can be used for pa...

XNA - Creating a lot of particles at the same time

Hello there, time for another XNA question. This time it is purely from a technical design standpoint though. My situation is this: I've created a particle-engine based on GPU-calculations, far from complete but it works. My GPU easily handles 10k particles without breaking a sweat and I wouldn't be surprised if I could add a bunch more...

How do those java sand games keep track of so many particles?

Can anyone shed any light on how a program like that might be structured? What java classes would they employ to keep track of so many particles and then check against them for things like collision detection? Particles need to know what particles they are next to, or that they're not next to anything so they can fall etc. Here's an ex...

Simple 1-D particle swarm optimization algorithm for a noisy environment

I'm experimenting with particle swarm optimisation and am trying to determine the best approach for the following simple scenario: Optimizing a 1-dimensional function (i.e. particles are moving along a single line) The function to be optimised can be sampled at any point on the line The "value" sampled for each position is very noisy T...

particle animation in iphone sdk

hai i'm in need of particle animation in my uiview based 2D game. At present i'm using the array of images for particle animations this make my app size increase some time leads to memory leak also. Is there is any way to make particle animation using core animation if it give me some sample codes. Thanks in Advance. ...