Computes the reciprocal square root (positive only) of the source scalar.
rsq dst, src |
---|
where
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.