rsq (Pixel Shader)

Computes the reciprocal square root (positive only) of the source scalar.

Syntax

rsq dst, src

where

dst is the destination register.
src is a source register. Source register requires explicit use of replicate swizzle, that is, exactly one of the .x, .y, .z, .w swizzle components (or the .r, .g, .b, .a equivalents) must be specified.

Pixel shader versions	1_1	1_2	1_3	1_4	2_0	2_x	2_sw	3_0	3_sw
rsq					x	x	x	x	x

The absolute value is taken before processing.

Precision should be at least 1.0/(2²²) absolute error over the range (1.0, 4.0) because common implementations will separate mantissa and exponent.

The output must be exactly 1.0 if the input is exactly 1.0. A source of 0.0 yields infinity.

Minimum operating system	Windows 98