# GLM: glm::core::function::common Namespace Reference

# glm::core::function::common Namespace Reference

Define common functions from Section 8.3 of GLSL 1.30.8 specification. Included in glm namespace. More...

## Functions

template<typename genFIType >
genFIType | abs (genFIType const &x)
| Returns x if x >= 0; otherwise, it returns -x.
template<typename genType >
genType | ceil (genType const &x)
| Returns a value equal to the nearest integer that is greater than or equal to x.
template<typename genUIFTypeT , typename genUIFTypeU >
genUIFTypeT | clamp (genUIFTypeT const &x, genUIFTypeU const &minVal, genUIFTypeU const &maxVal)
| Returns min(max(x, minVal), maxVal) for each component in x.
template<typename genType >
genType | floor (genType const &x)
| Returns a value equal to the nearest integer that is less then or equal to x.
template<typename genType >
genType | fract (genType const &x)
| Return x - floor(x).
template<typename genType >
genType::bool_type | isinf (genType const &x)
| Returns true if x holds a positive infinity or negative infinity representation in the underlying implementation's set of floating point representations.
template<typename genType >
genType::bool_type | isnan (genType const &x)
| Returns true if x holds a NaN (not a number) representation in the underlying implementation's set of floating point representations.
template<typename genUIFTypeT , typename genUIFTypeU >
genUIFTypeT | max (genUIFTypeT const &x, genUIFTypeU const &y)
| Returns y if x < y; otherwise, it returns x.
template<typename genUIFTypeT , typename genUIFTypeU >
genUIFTypeT | min (genUIFTypeT const &x, genUIFTypeU const &y)
| Returns y if y < x; otherwise, it returns x.
template<typename genTypeT , typename genTypeU >
genTypeT | mix (genTypeT const &x, genTypeT const &y, genTypeU const &a)
template<typename genTypeT , typename genTypeU >
genTypeT | mod (genTypeT const &x, genTypeU const &y)
| Modulus.
template<typename genType >
genType | modf (genType const &x, genType &i)
| Returns the fractional part of x and sets i to the integer part (as a whole number floating point value).
template<typename genType >
genType | round (genType const &x)
| Returns a value equal to the nearest integer to x.
template<typename genType >
genType | roundEven (genType const &x)
| Returns a value equal to the nearest integer to x.
template<typename genFIType >
genFIType | sign (genFIType const &x)
| Returns 1.0 if x > 0, 0.0 if x = 0, or -1.0 if x < 0.
template<typename genTypeT , typename genTypeU >
genTypeU | smoothstep (genTypeT const &edge0, genTypeT const &edge1, genTypeU const &x)
| Returns 0.0 if x <= edge0 and 1.0 if x >= edge1 and performs smooth Hermite interpolation between 0 and 1 when edge0 < x < edge1.
template<typename genTypeT , typename genTypeU >
genTypeU | step (genTypeT const &edge, genTypeU const &x)
| Returns 0.0 if x < edge, otherwise it returns 1.0.
template<typename genType >
genType | trunc (genType const &x)
| Returns a value equal to the nearest integer to x whose absolute value is not larger than the absolute value of x.

## Detailed Description

Define common functions from Section 8.3 of GLSL 1.30.8 specification. Included in glm namespace.

## Function Documentation

genFIType glm::core::function::common::abs | ( | genFIType const & | x | ) |

Returns x if x >= 0; otherwise, it returns -x.

(From GLSL 1.30.08 specification, section 8.3)

genType glm::core::function::common::ceil | ( | genType const & | x | ) |

Returns a value equal to the nearest integer that is greater than or equal to x.

(From GLSL 1.30.08 specification, section 8.3)

genUIFTypeT glm::core::function::common::clamp | ( | genUIFTypeT const & | x,
|  | genUIFTypeU const & | minVal,
|  | genUIFTypeU const & | maxVal |
| ) |  |  |

Returns min(max(x, minVal), maxVal) for each component in x.

using the floating-point values minVal and maxVal. (From GLSL 1.30.08 specification, section 8.3)

Referenced by glm::gtx::compatibility::saturate().

genType glm::core::function::common::floor | ( | genType const & | x | ) |

Returns a value equal to the nearest integer that is less then or equal to x.

(From GLSL 1.30.08 specification, section 8.3)

genType glm::core::function::common::fract | ( | genType const & | x | ) |

Return x - floor(x).

(From GLSL 1.30.08 specification, section 8.3)

genType::bool_type glm::core::function::common::isinf | ( | genType const & | x | ) |

Returns true if x holds a positive infinity or negative infinity representation in the underlying implementation's set of floating point representations.

Returns false otherwise, including for implementations with no infinity representations. (From GLSL 1.30.08 specification, section 8.3)

genType::bool_type glm::core::function::common::isnan | ( | genType const & | x | ) |

Returns true if x holds a NaN (not a number) representation in the underlying implementation's set of floating point representations.

Returns false otherwise, including for implementations with no NaN representations. (From GLSL 1.30.08 specification, section 8.3)

genUIFTypeT glm::core::function::common::max | ( | genUIFTypeT const & | x,
|  | genUIFTypeU const & | y |
| ) |  |  |

Returns y if x < y; otherwise, it returns x.

(From GLSL 1.30.08 specification, section 8.3)

genUIFTypeT glm::core::function::common::min | ( | genUIFTypeT const & | x,
|  | genUIFTypeU const & | y |
| ) |  |  |

Returns y if y < x; otherwise, it returns x.

(From GLSL 1.30.08 specification, section 8.3)

genTypeT glm::core::function::common::mix | ( | genTypeT const & | x,
|  | genTypeT const & | y,
|  | genTypeU const & | a |
| ) |  |  |

Returns:
  If genTypeU is a floating scalar or vector: Returns x * (1.0 - a) + y * a, i.e., the linear blend of x and y using the floating-point value a. The value for a is not restricted to the range [0, 1].
  If genTypeU is a boolean scalar or vector: Selects which vector each returned component comes from. For a component of a that is false, the corresponding component of x is returned. For a component of a that is true, the corresponding component of y is returned. Components of x and y that are not selected are allowed to be invalid floating point values and will have no effect on the results. Thus, this provides different functionality than genType mix(genType x, genType y, genType(a)) where a is a Boolean vector.

From GLSL 1.30.08 specification, section 8.3

Parameters:

  `[in]` | x | Floating point scalar or vector.
  `[in]` | y | Floating point scalar or vector.
  `[in]` | a | Floating point or boolean scalar or vector.

Referenced by glm::gtx::compatibility::lerp().

genTypeT glm::core::function::common::mod | ( | genTypeT const & | x,
|  | genTypeU const & | y |
| ) |  |  |

Modulus.

Returns x - y * floor(x / y) for each component in x using the floating point value y. (From GLSL 1.30.08 specification, section 8.3)

genType glm::core::function::common::modf | ( | genType const & | x,
|  | genType & | i |
| ) |  |  |

Returns the fractional part of x and sets i to the integer part (as a whole number floating point value).

Both the return value and the output parameter will have the same sign as x. (From GLSL 1.30.08 specification, section 8.3)

genType glm::core::function::common::round | ( | genType const & | x | ) |

Returns a value equal to the nearest integer to x.

The fraction 0.5 will round in a direction chosen by the implementation, presumably the direction that is fastest. This includes the possibility that round(x) returns the same value as roundEven(x) for all values of x. (From GLSL 1.30.08 specification, section 8.3)

genType glm::core::function::common::roundEven | ( | genType const & | x | ) |

Returns a value equal to the nearest integer to x.

A fractional part of 0.5 will round toward the nearest even integer. (Both 3.5 and 4.5 for x will return 4.0.) (From GLSL 1.30.08 specification, section 8.3)

genFIType glm::core::function::common::sign | ( | genFIType const & | x | ) |

Returns 1.0 if x > 0, 0.0 if x = 0, or -1.0 if x < 0.

(From GLSL 1.30.08 specification, section 8.3)

genTypeU glm::core::function::common::smoothstep | ( | genTypeT const & | edge0,
|  | genTypeT const & | edge1,
|  | genTypeU const & | x |
| ) |  |  |

Returns 0.0 if x <= edge0 and 1.0 if x >= edge1 and performs smooth Hermite interpolation between 0 and 1 when edge0 < x < edge1.

This is useful in cases where you would want a threshold function with a smooth transition. This is equivalent to: genType t; t = clamp ((x – edge0) / (edge1 – edge0), 0, 1); return t * t * (3 – 2 * t); Results are undefined if edge0 >= edge1. (From GLSL 1.30.08 specification, section 8.3)

genTypeU glm::core::function::common::step | ( | genTypeT const & | edge,
|  | genTypeU const & | x |
| ) |  |  |

Returns 0.0 if x < edge, otherwise it returns 1.0.

(From GLSL 1.30.08 specification, section 8.3)

genType glm::core::function::common::trunc | ( | genType const & | x | ) |

Returns a value equal to the nearest integer to x whose absolute value is not larger than the absolute value of x.

(From GLSL 1.30.08 specification, section 8.3)