# [−][src]Module pbrt::core::pbrt

Type definitions of Float and Spectrum, otherwise constants and functions which can be used almost everywhere else in the code.

## Constants

INV_2_PI | |

INV_4_PI | |

INV_PI | |

MACHINE_EPSILON | |

PI_OVER_2 | |

PI_OVER_4 | |

SHADOW_EPSILON | |

SQRT_2 |

## Functions

bits_to_float | Use |

clamp_t | Clamp the given value |

degrees | Convert from angles expressed in radians to degrees. |

erf | |

erf_inv | |

find_interval | Helper function which emulates the behavior of std::upper_bound(). |

float_to_bits | Use |

gamma | Error propagation. |

gamma_correct | Is used to write sRGB-compatible 8-bit image files. |

is_power_of_2 | Determine if a given integer is an exact power of 2. |

lerp | Interpolate linearly between two provided values. |

log_2 | |

log_2_int_i32 | Compute an integer base-2 logarithm function. |

log_2_int_i64 | Compute an integer base-2 logarithm function. |

log_2_int_u32 | Compute an integer base-2 logarithm function. |

log_2_int_u64 | Compute an integer base-2 logarithm function. |

mod_t | Computes the remainder of a/b. Provides the behavior that the modulus of a negative number is always positive. |

next_float_down | Bump a floating-point value down to the next smaller representable floating-point value. |

next_float_up | Bump a floating-point value up to the next greater representable floating-point value. |

quadratic | Find solution(s) of the quadratic equation at |

radians | Convert from angles expressed in degrees to radians. |

round_up_pow2_32 | Round an integer up to the next higher (or equal) power of 2. |

round_up_pow2_64 | Round an integer up to the next higher (or equal) power of 2. |

## Type Definitions

Float | |

Spectrum |