make the algorithm a bit more customizable

[xonotic/xonotic.git] / misc / tools / fft-normalmap-to-heightmap.c

diff --git a/misc/tools/fft-normalmap-to-heightmap.c b/misc/tools/fft-normalmap-to-heightmap.c
index 0c06f3dc74e06da915937bd95ef9054edd13ed2b..909f591ff33667355fec0f52bebdcb5d77ab219d 100644 (file)
--- a/misc/tools/fft-normalmap-to-heightmap.c
+++ b/misc/tools/fft-normalmap-to-heightmap.c
@@ -38,6 +38,8 @@
 void nmap_to_hmap(unsigned char *map, const unsigned char *refmap, int w, int h, double scale, double offset)
 {
        int x, y;
+       int fx, fy;
+       int ffx, ffy;
        double nx, ny, nz;
        double v, vmin, vmax;
 #ifndef C99
@@ -48,9 +50,9 @@ void nmap_to_hmap(unsigned char *map, const unsigned char *refmap, int w, int h,
        fftw_complex *imgspace2 = fftw_malloc(w*h * sizeof(fftw_complex));
        fftw_complex *freqspace1 = fftw_malloc(w*h * sizeof(fftw_complex));
        fftw_complex *freqspace2 = fftw_malloc(w*h * sizeof(fftw_complex));
-       fftw_plan i12f1 = fftw_plan_dft_2d(w, h, imgspace1, freqspace1, FFTW_FORWARD, FFTW_ESTIMATE);
-       fftw_plan i22f2 = fftw_plan_dft_2d(w, h, imgspace2, freqspace2, FFTW_FORWARD, FFTW_ESTIMATE);
-       fftw_plan f12i1 = fftw_plan_dft_2d(w, h, freqspace1, imgspace1, FFTW_BACKWARD, FFTW_ESTIMATE);
+       fftw_plan i12f1 = fftw_plan_dft_2d(h, w, imgspace1, freqspace1, FFTW_FORWARD, FFTW_ESTIMATE);
+       fftw_plan i22f2 = fftw_plan_dft_2d(h, w, imgspace2, freqspace2, FFTW_FORWARD, FFTW_ESTIMATE);
+       fftw_plan f12i1 = fftw_plan_dft_2d(h, w, freqspace1, imgspace1, FFTW_BACKWARD, FFTW_ESTIMATE);
 
        for(y = 0; y < h; ++y)
        for(x = 0; x < w; ++x)
@@ -86,23 +88,26 @@ void nmap_to_hmap(unsigned char *map, const unsigned char *refmap, int w, int h,
        for(y = 0; y < h; ++y)
        for(x = 0; x < w; ++x)
        {
-               int fx = x;
-               int fy = y;
+               fx = x;
+               fy = y;
                if(fx > w/2)
                        fx -= w;
                if(fy > h/2)
                        fy -= h;
+               /* these must have the same sign as fx and fy (so ffx*fx + ffy*fy is nonzero), otherwise do not matter */
+               ffx = fx;
+               ffy = fy;
 #ifdef C99
                if(fx||fy)
-                       freqspace1[(w*y+x)] = _Complex_I * (fx * freqspace1[(w*y+x)] + fy * freqspace2[(w*y+x)]) / (fx*fx + fy*fy) / TWO_PI;
+                       freqspace1[(w*y+x)] = _Complex_I * (ffx * freqspace1[(w*y+x)] + ffy * freqspace2[(w*y+x)]) / (ffx*fx + ffy*fy) / TWO_PI;
                else
                        freqspace1[(w*y+x)] = 0;
 #else
                if(fx||fy)
                {
                        save = freqspace1[(w*y+x)][0];
-                       freqspace1[(w*y+x)][0] = -(fx * freqspace1[(w*y+x)][1] + fy * freqspace2[(w*y+x)][1]) / (fx*fx + fy*fy) / TWO_PI;
-                       freqspace1[(w*y+x)][1] =  (fx * save + fy * freqspace2[(w*y+x)][0]) / (fx*fx + fy*fy) / TWO_PI;
+                       freqspace1[(w*y+x)][0] = -(ffx * freqspace1[(w*y+x)][1] + ffy * freqspace2[(w*y+x)][1]) / (ffx*fx + ffy*fy) / TWO_PI;
+                       freqspace1[(w*y+x)][1] =  (ffx * save + ffy * freqspace2[(w*y+x)][0]) / (ffx*fx + ffy*fy) / TWO_PI;
                }
                else
                {
@@ -114,16 +119,21 @@ void nmap_to_hmap(unsigned char *map, const unsigned char *refmap, int w, int h,
 
        fftw_execute(f12i1);
 
-       /* renormalize */
+       /* renormalize, find min/max */
+       vmin = vmax = 0;
        for(y = 0; y < h; ++y)
        for(x = 0; x < w; ++x)
        {
 #ifdef C99
-               imgspace1[(w*y+x)] /= (w*h);
+               v = creal(imgspace1[(w*y+x)] /= (w*h));
 #else
-               imgspace1[(w*y+x)][0] /= (w*h);
+               v = (imgspace1[(w*y+x)][0] /= (w*h));
                imgspace1[(w*y+x)][1] /= (w*h);
 #endif
+               if(v < vmin || (x == 0 && y == 0))
+                       vmin = v;
+               if(v > vmax || (x == 0 && y == 0))
+                       vmax = v;
        }
 
        if(refmap)
@@ -170,8 +180,6 @@ void nmap_to_hmap(unsigned char *map, const unsigned char *refmap, int w, int h,
                        s = 1;
                }
 
-               printf("Ref-computed scale: %f\nRef-computed offset: %f\n", s, o);
-
                /*
                 * now apply user-given offset and scale to these values
                 * (x * s + o) * scale + offset
@@ -182,35 +190,17 @@ void nmap_to_hmap(unsigned char *map, const unsigned char *refmap, int w, int h,
        }
        else if(scale == 0)
        {
-#ifdef C99
-               vmin = vmax = creal(imgspace1[0]);
-#else
-               vmin = vmax = imgspace1[0][0];
-#endif
-               for(y = 0; y < h; ++y)
-               for(x = 0; x < w; ++x)
-               {
-#ifdef C99
-                       v = creal(imgspace1[(w*y+x)]);
-#else
-                       v = imgspace1[(w*y+x)][0];
-#endif
-                       if(v < vmin)
-                               vmin = v;
-                       if(v > vmax)
-                               vmax = v;
-               }
-
                /*
                 * map vmin to -1
                 * map vmax to +1
                 */
                scale = 2 / (vmax - vmin);
                offset = -(vmax + vmin) / (vmax - vmin);
-
-               printf("Autocomputed scale: %f\nAutocomputed offset: %f\n", scale, offset);
        }
 
+       printf("Min: %f\nAvg: %f\nMax: %f\nScale: %f\nOffset: %f\nScaled-Min: %f\nScaled-Avg: %f\nScaled-Max: %f\n", 
+               vmin, 0.0, vmax, scale, offset, vmin * scale + offset, offset, vmax * scale + offset);
+
        for(y = 0; y < h; ++y)
        for(x = 0; x < w; ++x)
        {
@@ -250,9 +240,9 @@ void hmap_to_nmap(unsigned char *map, int w, int h, int src_chan, double scale)
        fftw_complex *imgspace2 = fftw_malloc(w*h * sizeof(fftw_complex));
        fftw_complex *freqspace1 = fftw_malloc(w*h * sizeof(fftw_complex));
        fftw_complex *freqspace2 = fftw_malloc(w*h * sizeof(fftw_complex));
-       fftw_plan i12f1 = fftw_plan_dft_2d(w, h, imgspace1, freqspace1, FFTW_FORWARD, FFTW_ESTIMATE);
-       fftw_plan f12i1 = fftw_plan_dft_2d(w, h, freqspace1, imgspace1, FFTW_BACKWARD, FFTW_ESTIMATE);
-       fftw_plan f22i2 = fftw_plan_dft_2d(w, h, freqspace2, imgspace2, FFTW_BACKWARD, FFTW_ESTIMATE);
+       fftw_plan i12f1 = fftw_plan_dft_2d(h, w, imgspace1, freqspace1, FFTW_FORWARD, FFTW_ESTIMATE);
+       fftw_plan f12i1 = fftw_plan_dft_2d(h, w, freqspace1, imgspace1, FFTW_BACKWARD, FFTW_ESTIMATE);
+       fftw_plan f22i2 = fftw_plan_dft_2d(h, w, freqspace2, imgspace2, FFTW_BACKWARD, FFTW_ESTIMATE);
 
        for(y = 0; y < h; ++y)
        for(x = 0; x < w; ++x)