I'm trying to implement fluid dynamics using compute shaders. In the article there are a series of passes done on a texture since this was written before compute shaders.
Would it be faster to do each pass on a texture or buffer? The final pass would have to be applied to a texture anyways.
I would recommend using whichever dimensionality of resource fits the simulation. If it's a 1D simulation, use a RWBuffer, if it's a 2D simulation use a RWTexture2D and if it's a 3D simulation use a RWTexture3D.
There appear to be stages in the algorithm that you linked that make use of bilinear filtering. If you restrict yourself to using a Buffer you'll have to issue 4 or 8 memory fetches (depending on 2D or 3D) and then more instructions to calculate the weighted average. Take advantage of the hardware's ability to do this for you where possible.
Another thing to be aware of is that data in textures is not laid out row by row (linearly) as you might expect, instead it's laid in such a way that neighbouring texels are as close to one another in memory as possible; this can be called Tiling or Swizzling depending on whose documentation you read. For that reason, unless your simulation is one-dimensional, you may well get far better cache coherency on reads/writes from a resource whose layout most closely matches the dimensions of the simulation.
