unpackUnorm2x16, unpackSnorm2x16, unpackUnorm4x8, unpackSnorm4x8 — unpack floating-point values from an unsigned integer
vec2 unpackUnorm2x16( | uint p); |
vec2 unpackSnorm2x16( | uint p); |
vec4 unpackUnorm4x8( | uint p); |
vec4 unpackSnorm4x8( | uint p); |
p Specifies an unsigned integer containing packed floating-point values.
unpackUnorm2x16, unpackSnorm2x16, unpackUnorm4x8, and 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:
unpackUnorm2x16: f / 65535.0
unpackSnorm2x16: clamp(f / 32727.0, -1.0, 1.0)
packUnorm4x8: f / 255.0
packSnorm4x8: 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 | |||
|---|---|---|---|
| Function Name | 1.00 | 3.00 | 3.10 |
| unpackUnorm2x16 | - | ✔ | ✔ |
| unpackSnorm2x16 | - | ✔ | ✔ |
| unpackUnorm4x8 | - | - | ✔ |
| unpackSnorm4x8 | - | - | ✔ |
clamp, packUnorm2x16, packSnorm2x16 packUnorm4x8 packSnorm4x8
Copyright © 2011-2014 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication License, v 1.0, 8 June 1999. https://opencontent.org/openpub/.