First commit - moving from LuaForge to SourceForge

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diff --git a/include/im_math.h b/include/im_math.h
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+/** \file
+ * \brief Math Utilities
+ *
+ * See Copyright Notice in im_lib.h
+ */
+
+#ifndef __IM_MATH_H
+#define __IM_MATH_H
+
+#include <math.h>
+#include "im_util.h"
+
+#ifdef IM_DEFMATHFLOAT
+inline float acosf(float _X) {return ((float)acos((double)_X)); }
+inline float asinf(float _X) {return ((float)asin((double)_X)); }
+inline float atanf(float _X) {return ((float)atan((double)_X)); }
+inline float atan2f(float _X, float _Y) {return ((float)atan2((double)_X, (double)_Y)); }
+inline float ceilf(float _X) {return ((float)ceil((double)_X)); }
+inline float cosf(float _X)  {return ((float)cos((double)_X)); }
+inline float coshf(float _X) {return ((float)cosh((double)_X)); }
+inline float expf(float _X) {return ((float)exp((double)_X)); }
+inline float fabsf(float _X) {return ((float)fabs((double)_X)); }
+inline float floorf(float _X) {return ((float)floor((double)_X)); }
+inline float fmodf(float _X, float _Y) {return ((float)fmod((double)_X, (double)_Y)); }
+inline float logf(float _X) {return ((float)log((double)_X)); }
+inline float log10f(float _X) {return ((float)log10((double)_X)); }
+inline float powf(float _X, float _Y) {return ((float)pow((double)_X, (double)_Y)); }
+inline float sinf(float _X) {return ((float)sin((double)_X)); }
+inline float sinhf(float _X) {return ((float)sinh((double)_X)); }
+inline float sqrtf(float _X) {return ((float)sqrt((double)_X)); }
+inline float tanf(float _X) {return ((float)tan((double)_X)); }
+inline float tanhf(float _X) {return ((float)tanh((double)_X)); }
+#endif
+
+/** \defgroup math Math Utilities
+ * \par
+ * When converting between continuous and discrete use: \n
+ * Continuous = Discrete + 0.5         [Reconstruction/Interpolation] \n
+ * Discrete = Round(Continuous - 0.5)  [Sampling/Quantization] \n
+ * \par
+ * Notice that must check 0-max limits when converting from Continuous to Discrete.
+ * \par
+ * When converting between discrete and discrete use: \n
+ * integer src_size, dst_len, src_i, dst_i            \n
+ * real factor = (real)(dst_size)/(real)(src_size)    \n
+ * dst_i = Round(factor*(src_i + 0.5) - 0.5)
+ * \par
+ * See \ref im_math.h
+ * \ingroup util */
+
+
+/** Round a real to the nearest integer.
+ * \ingroup math */
+inline int imRound(float x) 
+{
+  return (int)(x < 0? x-0.5f: x+0.5f);
+}
+inline int imRound(double x) 
+{
+  return (int)(x < 0? x-0.5: x+0.5);
+}
+
+/** Converts between two discrete grids.
+ * factor is "dst_size/src_size".
+ * \ingroup math */
+inline int imResample(int x, float factor)
+{
+  float xr = factor*(x + 0.5f) - 0.5f;
+  return (int)(xr < 0? xr-0.5f: xr+0.5f);  /* Round */
+}
+
+/** Does Zero Order Decimation (Mean).
+ * \ingroup math */
+template <class T, class TU>
+inline T imZeroOrderDecimation(int width, int height, T *map, float xl, float yl, float box_width, float box_height, TU Dummy)
+{
+  int x0,x1,y0,y1;
+  (void)Dummy;
+
+  x0 = (int)floor(xl - box_width/2.0 - 0.5) + 1;
+  y0 = (int)floor(yl - box_height/2.0 - 0.5) + 1;
+  x1 = (int)floor(xl + box_width/2.0 - 0.5);
+  y1 = (int)floor(yl + box_height/2.0 - 0.5);
+
+  if (x0 == x1) x1++;
+  if (y0 == y1) y1++;
+
+  x0 = x0<0? 0: x0>width-1? width-1: x0;
+  y0 = y0<0? 0: y0>height-1? height-1: y0;
+  x1 = x1<0? 0: x1>width-1? width-1: x1;
+  y1 = y1<0? 0: y1>height-1? height-1: y1;
+
+  TU Value;
+  int Count = 0;
+
+  Value = 0;
+
+  for (int y = y0; y <= y1; y++)
+  {
+    for (int x = x0; x <= x1; x++)
+    {
+      Value += map[y*width+x];
+      Count++;
+    }
+  }
+
+  if (Count == 0)
+  {
+    Value = 0;
+    return (T)Value;
+  }
+
+  return (T)(Value/(float)Count);
+}
+
+/** Does Bilinear Decimation.
+ * \ingroup math */
+template <class T, class TU>
+inline T imBilinearDecimation(int width, int height, T *map, float xl, float yl, float box_width, float box_height, TU Dummy)
+{
+  int x0,x1,y0,y1;
+  (void)Dummy;
+
+  x0 = (int)floor(xl - box_width/2.0 - 0.5) + 1;
+  y0 = (int)floor(yl - box_height/2.0 - 0.5) + 1;
+  x1 = (int)floor(xl + box_width/2.0 - 0.5);
+  y1 = (int)floor(yl + box_height/2.0 - 0.5);
+
+  if (x0 == x1) x1++;
+  if (y0 == y1) y1++;
+
+  x0 = x0<0? 0: x0>width-1? width-1: x0;
+  y0 = y0<0? 0: y0>height-1? height-1: y0;
+  x1 = x1<0? 0: x1>width-1? width-1: x1;
+  y1 = y1<0? 0: y1>height-1? height-1: y1;
+
+  TU Value, LineValue;
+  float LineNorm, Norm, dxr, dyr;
+
+  Value = 0;
+  Norm = 0;
+
+  for (int y = y0; y <= y1; y++)
+  {
+    dyr = yl - (y+0.5f);
+    if (dyr < 0) dyr *= -1;
+
+    LineValue = 0;
+    LineNorm = 0;
+
+    for (int x = x0; x <= x1; x++)
+    {
+      dxr = xl - (x+0.5f);
+      if (dxr < 0) dxr *= -1;
+
+      LineValue += map[y*width+x] * dxr;
+      LineNorm += dxr;
+    }
+
+    Value += LineValue * dyr;
+    Norm += dyr * LineNorm;
+  }
+
+  if (Norm == 0)
+  {
+    Value = 0;
+    return (T)Value;
+  }
+
+  return (T)(Value/Norm);
+}
+
+/** Does Zero Order Interpolation (Nearest Neighborhood).
+ * \ingroup math */
+template <class T>
+inline T imZeroOrderInterpolation(int width, int height, T *map, float xl, float yl)
+{
+  int x0 = imRound(xl-0.5f);
+  int y0 = imRound(yl-0.5f);
+  x0 = x0<0? 0: x0>width-1? width-1: x0;
+  y0 = y0<0? 0: y0>height-1? height-1: y0;
+  return map[y0*width + x0];
+}
+
+/** Does Bilinear Interpolation.
+ * \ingroup math */
+template <class T>
+inline T imBilinearInterpolation(int width, int height, T *map, float xl, float yl)
+{
+  int x0, y0, x1, y1;
+  float t, u;
+
+  if (xl < 0.5)
+  {
+    x1 = x0 = 0; 
+    t = 0;
+  }
+  else if (xl > width-0.5)
+  {
+    x1 = x0 = width-1;
+    t = 0;
+  }
+  else
+  {
+    x0 = (int)(xl-0.5f);
+    x1 = x0+1;
+    t = xl - (x0+0.5f);
+  }
+
+  if (yl < 0.5)
+  {
+    y1 = y0 = 0; 
+    u = 0;
+  }
+  else if (yl > height-0.5)
+  {
+    y1 = y0 = height-1;
+    u = 0;
+  }
+  else
+  {
+    y0 = (int)(yl-0.5f);
+    y1 = y0+1;
+    u = yl - (y0+0.5f);
+  }
+
+  T fll = map[y0*width + x0];
+  T fhl = map[y0*width + x1];
+  T flh = map[y1*width + x0];
+  T fhh = map[y1*width + x1];
+
+  return (T)((fhh - flh - fhl + fll) * u * t +
+                         (fhl - fll) * t +
+                         (flh - fll) * u +
+                                fll);
+}
+
+/** Does Bicubic Interpolation.
+ * \ingroup math */
+template <class T, class TU>
+inline T imBicubicInterpolation(int width, int height, T *map, float xl, float yl, TU Dummy)
+{
+  int X[4], Y[4];
+  float t, u;
+  (void)Dummy;
+
+  if (xl > width-0.5)
+  {
+    X[3] = X[2] = X[1] = width-1;
+    X[0] = X[1]-1;
+    t = 0;
+  }
+  else
+  {
+    X[1] = (int)(xl-0.5f);
+    if (X[1] < 0) X[1] = 0;
+
+    X[0] = X[1]-1;
+    X[2] = X[1]+1;
+    X[3] = X[1]+2;
+
+    if (X[0] < 0) X[0] = 0;
+    if (X[3] > width-1) X[3] = width-1;
+
+    t = xl - (X[1]+0.5f);
+  }
+
+  if (yl > height-0.5)
+  {
+    Y[3] = Y[2] = Y[1] = height-1;
+    Y[0] = Y[1]-1;
+    u = 0;
+  }
+  else
+  {
+    Y[1] = (int)(yl-0.5f);
+    if (Y[1] < 0) Y[1] = 0;
+
+    Y[0] = Y[1]-1;
+    Y[2] = Y[1]+1;
+    Y[3] = Y[1]+2;
+
+    if (Y[0] < 0) Y[0] = 0;
+    if (Y[3] > height-1) Y[3] = height-1;
+
+    u = yl - (Y[1]+0.5f);
+  }
+
+  float CX[4], CY[4];
+
+  // Optimize calculations
+  {
+    float c, c2, c3;
+
+#define C0 (-c3 + 2.0f*c2 - c)
+#define C1 ( c3 - 2.0f*c2 + 1.0f)
+#define C2 (-c3 + c2 + c)
+#define C3 ( c3 - c2)
+
+    c = t;
+    c2 = c*c; c3 = c2*c;
+    CX[0] = C0; CX[1] = C1; CX[2] = C2; CX[3] = C3;
+
+    c = u;
+    c2 = c*c; c3 = c2*c;
+    CY[0] = C0; CY[1] = C1; CY[2] = C2; CY[3] = C3;
+
+#undef C0
+#undef C1
+#undef C2
+#undef C3
+  }
+
+  TU LineValue, Value;
+  float LineNorm, Norm;
+
+  Value = 0;
+  Norm = 0;
+
+  for (int y = 0; y < 4; y++)
+  {
+    LineValue = 0;
+    LineNorm = 0;
+
+    for (int x = 0; x < 4; x++)
+    {
+      LineValue += map[Y[y]*width+X[x]] * CX[x];
+      LineNorm += CX[x];
+    }
+
+    Value += LineValue * CY[y];
+    Norm += CY[y] * LineNorm;
+  }
+
+  if (Norm == 0)
+  {
+    Value = 0;
+    return (T)Value;
+  }
+
+  Value = (Value/Norm);
+
+  int size = sizeof(T); 
+  if (size == 1)
+    return (T)(Value<=(TU)0? (TU)0: Value<=(TU)255? Value: (TU)255);
+  else
+    return (T)(Value);
+}
+
+/** Calculates minimum and maximum values.
+ * \ingroup math */
+template <class T> 
+inline void imMinMax(const T *map, int count, T& min, T& max)
+{
+  min = *map++;
+  max = min;
+  for (int i = 1; i < count; i++)
+  {
+    T value = *map++;
+
+    if (value > max)
+      max = value;
+    else if (value < min)
+      min = value;
+  }
+}
+
+#endif