4 replies to this topic

[lucky6969b]

What is the primitive typedef of half4 and half defined in Xoliulshader?
Want to use it in my D3D9 Project
Thanks
Jack

[Radikalizm]

Half primitives are usually half-precision (ie. 16-bit) floating point types, I'm not sure to which degree HLSL supports these (if at all) so a good alternative would be regular float primitives.

[Hodgman]

On old hardware, half will be a float with less precision, but possibly more speed.
On new hardware, half is treated the same as float.

[Matias Goldberg]

What Hodgman said. On G70 & G60 hardware (and some Intel chips) it will faster (up to 2x faster).
But beware that if you're using new hardware, you may miss a few bugs. I've had a case where a half was overflowing it's 16-bit precision, but on new HW it worked correctly because it was just being calculated in 32-bit precision.

When we tried it on old HW (an nForce 6150 & an Intel Mobile 4 Series to be exact), all hell break loose; and had to change a few variables from half to float (and add a clamp statement for a few halfs).

[lucky6969b]

Okay, thanks. I'll take thorough thought about it. Another question is do you guys know where the shadowmap function (the functor is pointing at) is? I guess it is in 3ds max, but can't find it anywhere
Thanks
Jack

Edited by lucky6969b, 11 November 2012 - 04:50 AM.