* Returns a uniform random number between 0 and * array_size - 1 (included) */

* Returns true if the current frame should be renderer at low resolution, false otherwise. * * This function is a simple helper that combines a f

* Returns true if the adaptive sampling buffers are ready for use, false otherwise. * * Adaptive sampling buffers are "ready for use" if the adapt

RGBE, aka R9G9B9E5_SHAREDEXP, is an unsigned float HDR pixel format where red, green, and blue all share the same exponent. The color channels store

* Reflects a ray about a normal. This function requires that dot(ray_direction, surface_normal) > 0 i.e. * ray_direction and surface_normal are in th

fast 0..255 * 0..255 => 0..255 rounded multiplication

* Balance heuristic for MIS weights computation * * This implementation already contains the 1/nb_pdf_a fraction of the MIS estimator. This means *

* Returns true if the given contribution satisfies the minimum light contribution * required for a light to be */

* Transforms V from its local space to the space around the normal */

if there's a pending marker from the entropy stream, return that otherwise, fetch from the stream and get a marker. if there's no marker, return 0xff,

* G1 Smith masking/shadowing (depending on whether local_direction is wo or wi) function * * Reference: [Understanding the Masking-Shadowing Functio

* Combines 'other_reservoir' into this reservoir * * 'target_function' is the target function evaluated at the pixel that is doing the

take a -128..127 value and stbi__clamp it and convert to 0..255

returns 1 if "a*b*c + add" has no negative terms/factors and doesn't overflow

* Returns true if in shadow (a hit was found before 't_max' distance * Returns false if unoccluded * * This function also uses NEE++ if enabled in

initialize a callback-based context

initialize a memory-decode context

* Evaluates the GGX anisotropic normal distribution function */

* This uses the technique from "Improved accuracy when building an orthonormal basis" by Nelson Max, * https://jcgt.org/published/0006/01/02. *

* 'clamp_condition' is an additional condition that needs to be met * for clamping to occur. If the additional condition is not met (the boolean * '

* Reference: * [1] [Open PBR Specification] https://academysoftwarefoundation.github.io/OpenPBR/#model/basesubstrate/translucentbase * * Given the