/*
 * Copyright 2011-2013 Blender Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "node_noise.h"
#include "stdcycles.h"
#include "vector2.h"
#include "vector4.h"

#define vector3 point

/* The following offset functions generate random offsets to be added to texture
 * coordinates to act as a seed since the noise functions don't have seed values.
 * A seed value is needed for generating distortion textures and color outputs.
 * The offset's components are in the range [100, 200], not too high to cause
 * bad precision and not to small to be noticeable. We use float seed because
 * OSL only support float hashes.
 */

float random_float_offset(float seed)
{
  return 100.0 + noise("hash", seed) * 100.0;
}

vector2 random_vector2_offset(float seed)
{
  return vector2(100.0 + noise("hash", seed, 0.0) * 100.0,
                 100.0 + noise("hash", seed, 1.0) * 100.0);
}

vector3 random_vector3_offset(float seed)
{
  return vector3(100.0 + noise("hash", seed, 0.0) * 100.0,
                 100.0 + noise("hash", seed, 1.0) * 100.0,
                 100.0 + noise("hash", seed, 2.0) * 100.0);
}

vector4 random_vector4_offset(float seed)
{
  return vector4(100.0 + noise("hash", seed, 0.0) * 100.0,
                 100.0 + noise("hash", seed, 1.0) * 100.0,
                 100.0 + noise("hash", seed, 2.0) * 100.0,
                 100.0 + noise("hash", seed, 3.0) * 100.0);
}

float noise_texture(float co, float detail, float distortion, output color Color)
{
  float p = co;
  if (distortion != 0.0) {
    p += safe_snoise(p + random_float_offset(0.0)) * distortion;
  }

  float value = fractal_noise(p, detail);
  Color = color(value,
                fractal_noise(p + random_float_offset(1.0), detail),
                fractal_noise(p + random_float_offset(2.0), detail));
  return value;
}

float noise_texture(vector2 co, float detail, float distortion, output color Color)
{
  vector2 p = co;
  if (distortion != 0.0) {
    p += vector2(safe_snoise(p + random_vector2_offset(0.0)) * distortion,
                 safe_snoise(p + random_vector2_offset(1.0)) * distortion);
  }

  float value = fractal_noise(p, detail);
  Color = color(value,
                fractal_noise(p + random_vector2_offset(2.0), detail),
                fractal_noise(p + random_vector2_offset(3.0), detail));
  return value;
}

float noise_texture(vector3 co, float detail, float distortion, output color Color)
{
  vector3 p = co;
  if (distortion != 0.0) {
    p += vector3(safe_snoise(p + random_vector3_offset(0.0)) * distortion,
                 safe_snoise(p + random_vector3_offset(1.0)) * distortion,
                 safe_snoise(p + random_vector3_offset(2.0)) * distortion);
  }

  float value = fractal_noise(p, detail);
  Color = color(value,
                fractal_noise(p + random_vector3_offset(3.0), detail),
                fractal_noise(p + random_vector3_offset(4.0), detail));
  return value;
}

float noise_texture(vector4 co, float detail, float distortion, output color Color)
{
  vector4 p = co;
  if (distortion != 0.0) {
    p += vector4(safe_snoise(p + random_vector4_offset(0.0)) * distortion,
                 safe_snoise(p + random_vector4_offset(1.0)) * distortion,
                 safe_snoise(p + random_vector4_offset(2.0)) * distortion,
                 safe_snoise(p + random_vector4_offset(3.0)) * distortion);
  }

  float value = fractal_noise(p, detail);
  Color = color(value,
                fractal_noise(p + random_vector4_offset(4.0), detail),
                fractal_noise(p + random_vector4_offset(5.0), detail));
  return value;
}

shader node_noise_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 dimensions = "3D",
                          vector3 Vector = vector3(0, 0, 0),
                          float W = 0.0,
                          float Scale = 5.0,
                          float Detail = 2.0,
                          float Distortion = 0.0,
                          output float Fac = 0.0,
                          output color Color = 0.0)
{
  vector3 p = Vector;
  if (use_mapping)
    p = transform(mapping, p);

  p *= Scale;
  float w = W * Scale;

  if (dimensions == "1D")
    Fac = noise_texture(w, Detail, Distortion, Color);
  else if (dimensions == "2D")
    Fac = noise_texture(vector2(p[0], p[1]), Detail, Distortion, Color);
  else if (dimensions == "3D")
    Fac = noise_texture(p, Detail, Distortion, Color);
  else if (dimensions == "4D")
    Fac = noise_texture(vector4(p[0], p[1], p[2], w), Detail, Distortion, Color);
  else
    error("Unknown dimension!");
}