#ifndef rdo_finish_H
#define rdo_finish_H
/* Optical properties of object surfaces. */

#define rdo_finish_H_COPYRIGHT "Copyright © 2008 Danillo Pereira and J. Stolfi, UNICAMP"
/* Last edited on 2024-12-21 11:54:12 by stolfi */

#include <stdio.h>

#include <frgb.h>
#include <vec.h>
#include <argparser.h>

#include <rdo_geometry.h>

typedef struct finish_t
  { char *name;         /* Name of finish (used to attach it to objects). */
    /* Spontaneous light emission parameters: */
    frgb_t emission;    /* Coefficient of spontaneous emission (`ambient'). */
    /* Light scattering parameters (components of the albedo):  */
    frgb_t diffusion;   /* Lambertian scattering coefficient. */
    frgb_t polish;      /* Polished scattering coefficient (`highlights'). */
    frgb_t reflection;  /* Mirror reflection coefficient.  */
  } finish_t;
  /* Optical properties of a surface. */

double rdo_finish_get_diffusion_coeff(finish_t *fn, int channel);
  /* Gets the Lambertian scattering (`diffusion') coefficient
    fo finish {fn} in the color band {channel}. */

double rdo_finish_get_emission_coeff(finish_t *fn, int channel);
  /* Gets the spontaneous Lambertian emission (`ambient coefficient' in raytracing jargon) 
    of finish {fn} in the color band {channel}. */

void rdo_finish_write(FILE *wr, finish_t *fn);
  /* Writes to {wr} a description of finish {fn}. */

finish_t rdo_finish_read(FILE *rd);
  /* Reads from {rd} the description of a surface finish,
    in the format produced by {rdo_write_finish}. */

void rdo_finish_check_max_albedo(finish_t *fn, double max_albedo);
  /* Checks whether the total albedo of {fn}, in any channel, exceeds
    the given {max_albedo}. If it does, aborts the program. */

/* LIST OF FINISHES */
  
vec_typedef(finish_vec_t, finish_vec, finish_t);
  /* A self-delimited vector of finishes, {v.e[0..v.ne-1]}.
    Also defines the functions {finish_vec_new()}, {finish_vec_expand()}, 
    {finish_vec_trim()}, {finish_vec_free()}. */

void rdo_finish_vec_write(FILE *wr, finish_vec_t *fns);
  /* Writes to {wr} the list of finishes {fns}. */

finish_vec_t rdo_finish_vec_read(FILE *rd);
  /* Reads from {rd}a list of finishes, in the 
    format produced by {rdo_finish_vec_write}. */

#endif