TODO: Simply return nullptr when failed to allocate?

C++ HeaderInfo to C EXRHeader conversion.

TODO(syoyo): Refactor function arguments.

out_data must be allocated initially with the block-header size of the current image(-part) type

* Evaluates the visible normal distribution function with GGX as * the normal disitrbution function * * Reference: [Sampling the GGX Distribution o

This function is needed to separate sum of Gaussians filters See separatedConvolutions.pdf in the FLIP repository: https://github.com/NVlabs/flip/blob

* Tests the visibility of the sample containde in 'reservoir' from the given shading point and kills the reservoir * if the visibility is occluded *

can save a single or multi-part image (no deep* formats)

* Reference: * * [1] [Global Illumination Compendium], https://people.cs.kuleuven.be/~philip.dutre/GI/TotalCompendium.pdf * * The sampled directio

* Returns false if the ray should be killed. * * This overload returns in 'throughput_scaling' the throughput scaling that * has been applied to '

* This function expects 'direction' to be in world space */

Evaluation XYZ sensitivity curves in Fourier space

* This function shoots a BSDF ray in the BVH containing only the emissive triangles of the scene * This may be useful in some algorithms for increase

* Extends this bounding box with the given one */

* This filter function handles self intersection avoidance and alpha testing * * return FALSE if the intersection is ACCEPTED * return true if the

* Reference: * [1] [A Hitchhiker's Guide to Multiple Scattering, Eugene d'Eon] https://eugenedeon.com/hitchhikers * Eq. 11.15 * * Hemispherical a

* Reference: * [1] [A Practical Extension to Microfacet Theory for the Modeling of Varying Iridescence, * Belcour, Barla, 2017, Su

* Essentially returns the RGB color associated with a wavelength. * * Only returns the color if the given 'wavelength' is negative. * If the wavel