/* SPDX-License-Identifier: Apache-2.0
 * Copyright 2011-2022 Blender Foundation */

#include "node_noise.h"
#include "stdcycles.h"

/* Wave */

float wave(point p_input,
           string type,
           string bands_direction,
           string rings_direction,
           string profile,
           float distortion,
           float detail,
           float dscale,
           float droughness,
           float phase)
{
  /* Prevent precision issues on unit coordinates. */
  point p = (p_input + 0.000001) * 0.999999;

  float n = 0.0;

  if (type == "bands") {
    if (bands_direction == "x") {
      n = p[0] * 20.0;
    }
    else if (bands_direction == "y") {
      n = p[1] * 20.0;
    }
    else if (bands_direction == "z") {
      n = p[2] * 20.0;
    }
    else { /* diagonal */
      n = (p[0] + p[1] + p[2]) * 10.0;
    }
  }
  else if (type == "rings") {
    point rp = p;
    if (rings_direction == "x") {
      rp *= point(0.0, 1.0, 1.0);
    }
    else if (rings_direction == "y") {
      rp *= point(1.0, 0.0, 1.0);
    }
    else if (rings_direction == "z") {
      rp *= point(1.0, 1.0, 0.0);
    }
    /* else: "spherical" */

    n = length(rp) * 20.0;
  }

  n += phase;

  if (distortion != 0.0) {
    n = n + (distortion * (fractal_noise(p * dscale, detail, droughness) * 2.0 - 1.0));
  }

  if (profile == "sine") {
    return 0.5 + 0.5 * sin(n - M_PI_2);
  }
  else if (profile == "saw") {
    n /= M_2PI;
    return n - floor(n);
  }
  else { /* profile tri */
    n /= M_2PI;
    return abs(n - floor(n + 0.5)) * 2.0;
  }
}

shader node_wave_texture(int use_mapping = 0,
                         matrix mapping = matrix(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
                         string wave_type = "bands",
                         string bands_direction = "x",
                         string rings_direction = "x",
                         string profile = "sine",
                         float Scale = 5.0,
                         float Distortion = 0.0,
                         float Detail = 2.0,
                         float DetailScale = 1.0,
                         float DetailRoughness = 0.5,
                         float PhaseOffset = 0.0,
                         point Vector = P,
                         output float Fac = 0.0,
                         output color Color = 0.0)
{
  point p = Vector;

  if (use_mapping)
    p = transform(mapping, p);

  Fac = wave(p * Scale,
             wave_type,
             bands_direction,
             rings_direction,
             profile,
             Distortion,
             Detail,
             DetailScale,
             DetailRoughness,
             PhaseOffset);
  Color = Fac;
}