Particles system on GPU

advanced
#1

Hi there,
I just read this-very-old-document but it has illustrated some concepts in my mind.

I need to setup a particles system (points based) based on GPU.
There is a couple of examples with OF but I cannot move further, stuck by some stuff.

Would someone help me to start a very basic example using floating point texture (instead of VBO as it seems a nicest way) ?

I don’t need collision and other particle/particle interaction (like flocking) but I guess that wouldn’t be hard to implement later if I needed that.

ANY help would be very appreciate :slight_smile:

#2

the whole process in this-document is also well described.

Anyway, I’m struggling with GPUparticleSystemExample example project in OF.

At first, I’d like to remove the use of spark.png and to replace the drawing by basic GL points.

any help would really be appreciated :slight_smile:

#3

Hey that looks like a good doc

If you just want to see some points, you can skip the geometry and fragment shader and just use the vertex shader.

in setup, change the updateRender setup to this

  
  
//    updateRender.setGeometryInputType(GL_POINTS);  
//	updateRender.setGeometryOutputType(GL_TRIANGLE_STRIP);  
//	updateRender.setGeometryOutputCount(6);  
//    updateRender.load("shaders/render.vert","shaders/render.frag","shaders/render.geom");  
    updateRender.load("shaders/render.vert","");

so it will only be using the vertex shader.

Then in the vertex shader you make one change

  
  
    gl_Position = gl_ModelViewProjectionMatrix * pixPos ;  
//    gl_Position = pixPos;

and i think that should be it

#4

it works very fine + I just understood more how to do that.
thanks a lot.

now, moving to implement more things on gpu (movements equations including attractors etc )

gpu.PNG1138×904