gistfile1.cs

  public Color GetInterpolatedPixel(float x, float y, float z) {
    x = Mathf.Clamp(x, 0, size - 1);
    y = Mathf.Clamp(y, 0, size - 1);
    z = Mathf.Clamp(z, 0, size - 1);

    int lowerX = Mathf.Clamp(Mathf.FloorToInt(x), 0, size - 1);
    int upperX = Mathf.Clamp(lowerX + 1, 0, size - 1);

    int lowerY = Mathf.Clamp(Mathf.FloorToInt(y), 0, size - 1);
    int upperY = Mathf.Clamp(lowerY + 1, 0, size - 1);

    int lowerZ = Mathf.Clamp(Mathf.FloorToInt(z), 0, size - 1);
    int upperZ = Mathf.Clamp(lowerZ + 1, 0, size - 1);

    Color C000 = GetPixel(lowerX, lowerY, lowerZ);
    Color C010 = GetPixel(lowerX, lowerY, upperZ);
    Color C100 = GetPixel(upperX, lowerY, lowerZ);
    Color C001 = GetPixel(lowerX, upperY, lowerZ);
    Color C110 = GetPixel(upperX, lowerY, upperZ);
    Color C111 = GetPixel(upperX, upperY, upperZ);
    Color C101 = GetPixel(upperX, upperY, lowerZ);
    Color C011 = GetPixel(lowerX, upperY, upperZ);

    Color C00  = Color.Lerp(C000, C100, upperX - x);
    Color C10  = Color.Lerp(C010, C110, upperX - x);
    Color C01  = Color.Lerp(C001, C101, upperX - x);
    Color C11  = Color.Lerp(C011, C111, upperX - x);

    Color C1 = Color.Lerp(C01, C11, upperZ - z);
    Color C0 = Color.Lerp(C00, C10, upperZ - z);

    return Color.Lerp(C0, C1, upperY - y);
  }