/// <summary>
/// Create Normal Map Texture.
/// </summary>
/// <param name="img">Reference FloatImage.</param>
/// <param name="wm">Texture Wrap Mode.</param>
/// <param name="heightWeights">float[4]-> Color Weights.</param>
/// <param name="kdu">Kernel U.</param>
/// <param name="kdv">Kernel V.</param>
/// <returns></returns>
public static FloatImage CreateNormalMap(FloatImage img, WrapMode wm, float[] heightWeights, Kernel2 kdu, Kernel2 kdv, ParsePixelEventHandler pixelParseEvent)
{
int w = (int)img.Width;
int h = (int)img.Height;
bool canceled = false;
FloatImage fimage = new FloatImage();
fimage.Allocate(4, w, h);
unsafe
{
float* alphaChannel = fimage.Channel(3);
int x = 0, y = 0;
for (uint i = 0; i < w * h; i++)
{
float r = img.Pixel((uint)x, (uint)y, 0);
float g = img.Pixel((uint)x, (uint)y, 1);
float b = img.Pixel((uint)x, (uint)y, 2);
float a = img.ComponentCount > 3 ? img.Pixel((uint)x, (uint)y, 3) : 255f;
float[] color = ColorToVector4(r, g, b, a);
alphaChannel[i] = Float4Dot(color, heightWeights);
if (!pixelParseEvent())
{
canceled = true;
break;
}
x++;
if (x >= w)
{
x = 0;
y++;
}
}
float heightScale = 1.0f / 16.0f; // @@ Use a user defined factor.
for (y = 0; y < h; y++)
{
for (x = 0; x < w; x++)
{
float du = fimage.ApplyKernel(kdu, x, y, 3, wm);
float dv = fimage.ApplyKernel(kdv, x, y, 3, wm);
float[] n = Float3Normalize(new float[] { du, dv, heightScale });
fimage.SetPixel(0.5f * n[0] + 0.5f, (uint)x, (uint)y, 0);
fimage.SetPixel(0.5f * n[1] + 0.5f, (uint)x, (uint)y, 1);
fimage.SetPixel(0.5f * n[2] + 0.5f, (uint)x, (uint)y, 2);
if (canceled)
break;
if (!pixelParseEvent())
{
canceled = true;
break;
}
}
if (canceled)
break;
}
}
return fimage;
}
/// <summary>
/// Create a new Instance of Kernel Filter.
/// </summary>
/// <param name="k">Base Kernel to Copy.</param>
public Kernel2(Kernel2 k)
{
m_windowSize = k.m_windowSize;
m_data = new float[m_windowSize * m_windowSize];
for (uint i = 0; i < m_windowSize * m_windowSize; i++)
{
m_data[i] = k.m_data[i];
}
}
/// <summary>
/// Apply Kernel Filter to Image.
/// </summary>
/// <param name="k">Kernel Filter.</param>
/// <param name="x">X Position.</param>
/// <param name="y">Y Position.</param>
/// <param name="c">Channel.</param>
/// <param name="wm">Wrap Mode.</param>
/// <returns></returns>
public float ApplyKernel(Kernel2 k, int x, int y, uint c, WrapMode wm)
{
uint kernelWindow = k.windowSize();
int kernelOffset = (int)(kernelWindow / 2) - 1;
float sum = 0.0f;
unsafe
{
float* channel = this.Channel(c);
for (uint i = 0; i < kernelWindow; i++)
{
int src_y = (int)(y + i) - kernelOffset;
for (uint e = 0; e < kernelWindow; e++)
{
int src_x = (int)(x + e) - kernelOffset;
int idx = (int)this.Index(src_x, src_y, wm);
sum += k.valueAt(e, i) * channel[idx];
}
}
}
return sum;
}
/// <summary>
/// Create Normal Map Texture.
/// </summary>
/// <param name="img">Reference FloatImage.</param>
/// <param name="wm">Texture Wrap Mode.</param>
/// <param name="heightWeights">float[4]-> Color Weights.</param>
/// <param name="filterWeights">float[4]-> Filter Weights.</param>
/// <returns></returns>
public static FloatImage CreateNormalMap(FloatImage img, WrapMode wm, float[] heightWeights, float[] filterWeights, ParsePixelEventHandler pixelParseEvent)
{
Kernel2 kdu;
Kernel2 kdv;
kdu = new Kernel2(9);
kdu.initBlendedSobel(filterWeights);
kdu.normalize();
kdv = new Kernel2(kdu);
kdv.transpose();
return CreateNormalMap(img, wm, heightWeights, kdu, kdv, pixelParseEvent);
}
/// <summary>
/// Create Normal Map Texture.
/// </summary>
/// <param name="img">Reference Bitmap.</param>
/// <param name="wm">Texture Wrap Mode.</param>
/// <param name="heightWeights">float[4]-> Color Weights.</param>
/// <param name="kdu">Kernel U.</param>
/// <param name="kdv">Kernel V.</param>
/// <returns></returns>
public static FloatImage CreateNormalMap(Bitmap img, WrapMode wm, float[] heightWeights, Kernel2 kdu, Kernel2 kdv, ParsePixelEventHandler pixelParseEvent)
{
FloatImage tmp = new FloatImage();
tmp.InitFrom(img);
return CreateNormalMap(tmp, wm, heightWeights, kdu, kdv, pixelParseEvent);
}
