Hello everyone!

Here is my dilemma. I'm writing a GPU based particle system in HLSL to be used in XNA. I'm using a set of vertex textures which hold the data pertaining to properties of a particle such as initial position, rotation, scale and the like.

However, my attribute texture is where I'm running into a bit of trouble. Each pixel in the texture is of the type float4, but I need more than 4 numbers to really do what I want with each particle. The r, g and b values in the attribute texture have been used and have to remain floats. The values I need to represent with the alpha, on the other hand, do not need the precision of a floating point number.

So I was thinking. Wouldn't it be possible to have HalfSingle array on the CPU side of the program which is holding these values that I need on the GPU, and use some unsafe C# code and pointers to compose that HalfSingle array into a float, then set it to the alpha value for a specific pixel. From there in the HLSL code I would need to decompose this float in to two halfs.

This is where my problem lies, since HLSL does not support pointers how could I do this? Is it possible?

Thanks in advance!