path: root/noiseutils/noiseutils.cpp

// noiseutils.cpp
//
// Copyright (C) 2003-2005 Jason Bevins
//
// This library is free software; you can redistribute it and/or modify it
// under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation; either version 2.1 of the License, or (at
// your option) any later version.
//
// This library is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
// License (COPYING.txt) for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with this library; if not, write to the Free Software Foundation,
// Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
//
// The developer's email is jlbezigvins@gmzigail.com (for great email, take
// off every 'zig'.)
//

#include <fstream>

#include <noise/interp.h>
#include <noise/mathconsts.h>

#include "noiseutils.h"

using namespace noise;
using namespace noise::model;
using namespace noise::module;

// Bitmap header size.
const int BMP_HEADER_SIZE = 54;

// Direction of the light source, in compass degrees (0 = north, 90 = east,
// 180 = south, 270 = east)
const double DEFAULT_LIGHT_AZIMUTH = 45.0;

// Amount of contrast between light and dark areas.
const double DEFAULT_LIGHT_CONTRAST  =  1.0;

// Elevation of the light source above the horizon, in degrees (0 = on
// horizon, 90 = directly overhead)
const double DEFAULT_LIGHT_ELEVATION = 45.0;

//////////////////////////////////////////////////////////////////////////////
// Miscellaneous functions

namespace noise
{

  namespace utils
  {

    // Performs linear interpolation between two 8-bit channel values.
    inline noise::uint8 BlendChannel (const uint8 channel0,
      const uint8 channel1, float alpha)
    {
      float c0 = (float)channel0 / 255.0;
      float c1 = (float)channel1 / 255.0;
      return (noise::uint8)(((c1 * alpha) + (c0 * (1.0f - alpha))) * 255.0f);
    }

    // Performs linear interpolation between two colors and stores the result
    // in out.
    inline void LinearInterpColor (const Color& color0, const Color& color1,
      float alpha, Color& out)
    {
      out.alpha = BlendChannel (color0.alpha, color1.alpha, alpha);
      out.blue  = BlendChannel (color0.blue , color1.blue , alpha);
      out.green = BlendChannel (color0.green, color1.green, alpha);
      out.red   = BlendChannel (color0.red  , color1.red  , alpha);
    }

    // Unpacks a floating-point value into four bytes.  This function is
    // specific to Intel machines.  A portable version will come soon (I
    // hope.)
    inline noise::uint8* UnpackFloat (noise::uint8* bytes, float value)
    {
      noise::uint8* pBytes = (noise::uint8*)(&value);
      bytes[0] = *pBytes++;
      bytes[1] = *pBytes++;
      bytes[2] = *pBytes++;
      bytes[3] = *pBytes++;
      return bytes;
    }

    // Unpacks a 16-bit integer value into two bytes in little endian format.
    inline noise::uint8* UnpackLittle16 (noise::uint8* bytes,
      noise::uint16 integer)
    {
      bytes[0] = (noise::uint8)((integer & 0x00ff)      );
      bytes[1] = (noise::uint8)((integer & 0xff00) >> 8 );
      return bytes;
    }

    // Unpacks a 32-bit integer value into four bytes in little endian format.
    inline noise::uint8* UnpackLittle32 (noise::uint8* bytes,
      noise::uint32 integer)
    {
      bytes[0] = (noise::uint8)((integer & 0x000000ff)      );
      bytes[1] = (noise::uint8)((integer & 0x0000ff00) >> 8 );
      bytes[2] = (noise::uint8)((integer & 0x00ff0000) >> 16);
      bytes[3] = (noise::uint8)((integer & 0xff000000) >> 24);
      return bytes;
    }

  }

}

using namespace noise;

using namespace noise::utils;

//////////////////////////////////////////////////////////////////////////////
// GradientColor class

GradientColor::GradientColor ()
{
  m_pGradientPoints = NULL;
}

GradientColor::~GradientColor ()
{
  delete[] m_pGradientPoints;
}

void GradientColor::AddGradientPoint (double gradientPos,
  const Color& gradientColor)
{
  // Find the insertion point for the new gradient point and insert the new
  // gradient point at that insertion point.  The gradient point array will
  // remain sorted by gradient position.
  int insertionPos = FindInsertionPos (gradientPos);
  InsertAtPos (insertionPos, gradientPos, gradientColor);
}

void GradientColor::Clear ()
{
  delete[] m_pGradientPoints;
  m_pGradientPoints = NULL;
  m_gradientPointCount = 0;
}

int GradientColor::FindInsertionPos (double gradientPos)
{
  int insertionPos;
  for (insertionPos = 0; insertionPos < m_gradientPointCount;
    insertionPos++) {
    if (gradientPos < m_pGradientPoints[insertionPos].pos) {
      // We found the array index in which to insert the new gradient point.
      // Exit now.
      break;
    } else if (gradientPos == m_pGradientPoints[insertionPos].pos) {
      // Each gradient point is required to contain a unique gradient
      // position, so throw an exception.
      throw noise::ExceptionInvalidParam ();
    }
  }
  return insertionPos;
}

const Color& GradientColor::GetColor (double gradientPos) const
{
  assert (m_gradientPointCount >= 2);

  // Find the first element in the gradient point array that has a gradient
  // position larger than the gradient position passed to this method.
  int indexPos;
  for (indexPos = 0; indexPos < m_gradientPointCount; indexPos++) {
    if (gradientPos < m_pGradientPoints[indexPos].pos) {
      break;
    }
  }

  // Find the two nearest gradient points so that we can perform linear
  // interpolation on the color.
  int index0 = ClampValue (indexPos - 1, 0, m_gradientPointCount - 1);
  int index1 = ClampValue (indexPos    , 0, m_gradientPointCount - 1);

  // If some gradient points are missing (which occurs if the gradient
  // position passed to this method is greater than the largest gradient
  // position or less than the smallest gradient position in the array), get
  // the corresponding gradient color of the nearest gradient point and exit
  // now.
  if (index0 == index1) {
    m_workingColor = m_pGradientPoints[index1].color;
    return m_workingColor;
  }
  
  // Compute the alpha value used for linear interpolation.
  double input0 = m_pGradientPoints[index0].pos;
  double input1 = m_pGradientPoints[index1].pos;
  double alpha = (gradientPos - input0) / (input1 - input0);

  // Now perform the linear interpolation given the alpha value.
  const Color& color0 = m_pGradientPoints[index0].color;
  const Color& color1 = m_pGradientPoints[index1].color;
  LinearInterpColor (color0, color1, (float)alpha, m_workingColor);
  return m_workingColor;
}

void GradientColor::InsertAtPos (int insertionPos, double gradientPos,
  const Color& gradientColor)
{
  // Make room for the new gradient point at the specified insertion position
  // within the gradient point array.  The insertion position is determined by
  // the gradient point's position; the gradient points must be sorted by
  // gradient position within that array.
  GradientPoint* newGradientPoints;
  newGradientPoints = new GradientPoint[m_gradientPointCount + 1];
  for (int i = 0; i < m_gradientPointCount; i++) {
    if (i < insertionPos) {
      newGradientPoints[i] = m_pGradientPoints[i];
    } else {
      newGradientPoints[i + 1] = m_pGradientPoints[i];
    }
  }
  delete[] m_pGradientPoints;
  m_pGradientPoints = newGradientPoints;
  ++m_gradientPointCount;

  // Now that we've made room for the new gradient point within the array, add
  // the new gradient point.
  m_pGradientPoints[insertionPos].pos = gradientPos ;
  m_pGradientPoints[insertionPos].color = gradientColor;
}

//////////////////////////////////////////////////////////////////////////////
// NoiseMap class

NoiseMap::NoiseMap ()
{
  InitObj ();
}

NoiseMap::NoiseMap (int width, int height)
{
  InitObj ();
  SetSize (width, height);
}

NoiseMap::NoiseMap (const NoiseMap& rhs)
{
  InitObj ();
  CopyNoiseMap (rhs);
}

NoiseMap::~NoiseMap ()
{
  delete[] m_pNoiseMap;
}

NoiseMap& NoiseMap::operator= (const NoiseMap& rhs)
{
  CopyNoiseMap (rhs);

  return *this;
}

void NoiseMap::Clear (float value)
{
  if (m_pNoiseMap != NULL) {
    for (int y = 0; y < m_height; y++) {
      float* pDest = GetSlabPtr (0, y);
      for (int x = 0; x < m_width; x++) {
        *pDest++ = value;
      }
    }
  }
}

void NoiseMap::CopyNoiseMap (const NoiseMap& source)
{
  // Resize the noise map buffer, then copy the slabs from the source noise
  // map buffer to this noise map buffer.
  SetSize (source.GetWidth (), source.GetHeight ());
  for (int y = 0; y < source.GetHeight (); y++) {
    const float* pSource = source.GetConstSlabPtr (0, y);
    float* pDest = GetSlabPtr (0, y);
    memcpy (pDest, pSource, (size_t)source.GetWidth () * sizeof (float));
  }

  // Copy the border value as well.
  m_borderValue = source.m_borderValue;
}

void NoiseMap::DeleteNoiseMapAndReset ()
{
  delete[] m_pNoiseMap;
  InitObj ();
}

float NoiseMap::GetValue (int x, int y) const
{
  if (m_pNoiseMap != NULL) {
    if (x >= 0 && x < m_width && y >= 0 && y < m_height) {
      return *(GetConstSlabPtr (x, y));
    }
  }
  // The coordinates specified are outside the noise map.  Return the border
  // value.
  return m_borderValue;
}

void NoiseMap::InitObj ()
{
  m_pNoiseMap = NULL;
  m_height    = 0;
  m_width     = 0;
  m_stride    = 0;
  m_memUsed   = 0;
  m_borderValue = 0.0;
}

void NoiseMap::ReclaimMem ()
{
  size_t newMemUsage = CalcMinMemUsage (m_width, m_height);
  if (m_memUsed > newMemUsage) {
    // There is wasted memory.  Create the smallest buffer that can fit the
    // data and copy the data to it.
    float* pNewNoiseMap = NULL;
    try {
      pNewNoiseMap = new float[newMemUsage];
    }
    catch (...) {
      throw noise::ExceptionOutOfMemory ();
    }
    memcpy (pNewNoiseMap, m_pNoiseMap, newMemUsage * sizeof (float));
    delete[] m_pNoiseMap;
    m_pNoiseMap = pNewNoiseMap;
    m_memUsed = newMemUsage;
  }
}

void NoiseMap::SetSize (int width, int height)
{
  if (width < 0 || height < 0
    || width > RASTER_MAX_WIDTH || height > RASTER_MAX_HEIGHT) {
    // Invalid width or height.
    throw noise::ExceptionInvalidParam ();
  } else if (width == 0 || height == 0) {
    // An empty noise map was specified.  Delete it and zero out the size
    // member variables.
    DeleteNoiseMapAndReset ();
  } else {
    // A new noise map size was specified.  Allocate a new noise map buffer
    // unless the current buffer is large enough for the new noise map (we
    // don't want costly reallocations going on.)
    size_t newMemUsage = CalcMinMemUsage (width, height);
    if (m_memUsed < newMemUsage) {
      // The new size is too big for the current noise map buffer.  We need to
      // reallocate.
      DeleteNoiseMapAndReset ();
      try {
        m_pNoiseMap = new float[newMemUsage];
      }
      catch (...) {
        throw noise::ExceptionOutOfMemory ();
      }
      m_memUsed = newMemUsage;
    }
    m_stride = (int)CalcStride (width);
    m_width  = width;
    m_height = height;
  }
}

void NoiseMap::SetValue (int x, int y, float value)
{
  if (m_pNoiseMap != NULL) {
    if (x >= 0 && x < m_width && y >= 0 && y < m_height) {
      *(GetSlabPtr (x, y)) = value;
    }
  }
}

void NoiseMap::TakeOwnership (NoiseMap& source)
{
  // Copy the values and the noise map buffer from the source noise map to
  // this noise map.  Now this noise map pwnz the source buffer.
  delete[] m_pNoiseMap;
  m_memUsed   = source.m_memUsed;
  m_height    = source.m_height;
  m_pNoiseMap = source.m_pNoiseMap;
  m_stride    = source.m_stride;
  m_width     = source.m_width;

  // Now that the source buffer is assigned to this noise map, reset the
  // source noise map object.
  source.InitObj ();
}

//////////////////////////////////////////////////////////////////////////////
// Image class

Image::Image ()
{
  InitObj ();
}

Image::Image (int width, int height)
{
  InitObj ();
  SetSize (width, height);
}

Image::Image (const Image& rhs)
{
  InitObj ();
  CopyImage (rhs);
}

Image::~Image ()
{
  delete[] m_pImage;
}

Image& Image::operator= (const Image& rhs)
{
  CopyImage (rhs);

  return *this;
}

void Image::Clear (const Color& value)
{
  if (m_pImage != NULL) {
    for (int y = 0; y < m_height; y++) {
      Color* pDest = GetSlabPtr (0, y);
      for (int x = 0; x < m_width; x++) {
        *pDest++ = value;
      }
    }
  }
}

void Image::CopyImage (const Image& source)
{
  // Resize the image buffer, then copy the slabs from the source image
  // buffer to this image buffer.
  SetSize (source.GetWidth (), source.GetHeight ());
  for (int y = 0; y < source.GetHeight (); y++) {
    const Color* pSource = source.GetConstSlabPtr (0, y);
    Color* pDest = GetSlabPtr (0, y);
    memcpy (pDest, pSource, (size_t)source.GetWidth () * sizeof (float));
  }

  // Copy the border value as well.
  m_borderValue = source.m_borderValue;
}

void Image::DeleteImageAndReset ()
{
  delete[] m_pImage;
  InitObj ();
}

Color Image::GetValue (int x, int y) const
{
  if (m_pImage != NULL) {
    if (x >= 0 && x < m_width && y >= 0 && y < m_height) {
      return *(GetConstSlabPtr (x, y));
    }
  }
  // The coordinates specified are outside the image.  Return the border
  // value.
  return m_borderValue;
}

void Image::InitObj ()
{
  m_pImage  = NULL;
  m_height  = 0;
  m_width   = 0;
  m_stride  = 0;
  m_memUsed = 0;
  m_borderValue = Color (0, 0, 0, 0);
}

void Image::ReclaimMem ()
{
  size_t newMemUsage = CalcMinMemUsage (m_width, m_height);
  if (m_memUsed > newMemUsage) {
    // There is wasted memory.  Create the smallest buffer that can fit the
    // data and copy the data to it.
    Color* pNewImage = NULL;
    try {
      pNewImage = new Color[newMemUsage];
    }
    catch (...) {
      throw noise::ExceptionOutOfMemory ();
    }
    memcpy (pNewImage, m_pImage, newMemUsage * sizeof (float));
    delete[] m_pImage;
    m_pImage = pNewImage;
    m_memUsed = newMemUsage;
  }
}

void Image::SetSize (int width, int height)
{
  if (width < 0 || height < 0
    || width > RASTER_MAX_WIDTH || height > RASTER_MAX_HEIGHT) {
    // Invalid width or height.
    throw noise::ExceptionInvalidParam ();
  } else if (width == 0 || height == 0) {
    // An empty image was specified.  Delete it and zero out the size member
    // variables.
    DeleteImageAndReset ();
  } else {
    // A new image size was specified.  Allocate a new image buffer unless
    // the current buffer is large enough for the new image (we don't want
    // costly reallocations going on.)
    size_t newMemUsage = CalcMinMemUsage (width, height);
    if (m_memUsed < newMemUsage) {
      // The new size is too big for the current image buffer.  We need to
      // reallocate.
      DeleteImageAndReset ();
      try {
        m_pImage = new Color[newMemUsage];
      }
      catch (...) {
        throw noise::ExceptionOutOfMemory ();
      }
      m_memUsed = newMemUsage;
    }
    m_stride = (int)CalcStride (width);
    m_width  = width;
    m_height = height;
  }
}

void Image::SetValue (int x, int y, const Color& value)
{
  if (m_pImage != NULL) {
    if (x >= 0 && x < m_width && y >= 0 && y < m_height) {
      *(GetSlabPtr (x, y)) = value;
    }
  }
}

void Image::TakeOwnership (Image& source)
{
  // Copy the values and the image buffer from the source image to this image.
  // Now this image pwnz the source buffer.
  delete[] m_pImage;
  m_memUsed = source.m_memUsed;
  m_height  = source.m_height;
  m_pImage  = source.m_pImage;
  m_stride  = source.m_stride;
  m_width   = source.m_width;

  // Now that the source buffer is assigned to this image, reset the source
  // image object.
  source.InitObj ();
}

/////////////////////////////////////////////////////////////////////////////
// WriterBMP class

int WriterBMP::CalcWidthByteCount (int width) const
{
  return ((width * 3) + 3) & ~0x03;
}

void WriterBMP::WriteDestFile ()
{
  if (m_pSourceImage == NULL) {
    throw noise::ExceptionInvalidParam ();
  }

  int width  = m_pSourceImage->GetWidth  ();
  int height = m_pSourceImage->GetHeight ();

  // The width of one line in the file must be aligned on a 4-byte boundary.
  int bufferSize = CalcWidthByteCount (width);
  int destSize   = bufferSize * height;

  // This buffer holds one horizontal line in the destination file.
  noise::uint8* pLineBuffer = NULL;

  // File object used to write the file.
  std::ofstream os;
  os.clear ();
  
  // Allocate a buffer to hold one horizontal line in the bitmap.
  try {
    pLineBuff