unpackUnorm2x16, unpackSnorm2x16, unpackUnorm4x8, unpackSnorm4x8 — unpack floating-point values from an unsigned integer
Specifies an unsigned integer containing packed floating-point values.
unpackSnorm4x8 unpack single 32-bit
unsigned integers, specified in the parameter
p into a pair of 16-bit unsigned
integers. a pair of 16-bit signed integers, four 8-bit unsigned
integers, or four 8-bit signed integers respectively. Then, each
component is converted to a normalized floating-point value to
generate the returned two- or four-component vector.
The conversion for unpacked fixed point value f to floating-point is performed as follows:
f / 65535.0
clamp(f / 32727.0, -1.0, 1.0)
f / 255.0
clamp(f / 127.0, -1.0, 1.0)
The first component of the returned vector will be extracted from the least significant bits of the input; the last component will be extracted from the most significant bits.
|OpenGL ES Shading Language Version|
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