libtthimage/Lib/pov_hf15f.c

135 lines
2.8 KiB
C

/*
pov_hf15f.c
===========
traitement des bords des height-fields.
---------------------------------------
new 3 octobre 2009 - avenue StExupery
*/
#include <stdio.h>
#include <stdlib.h>
#include "../tthimage.h"
/*::------------------------------------------------------------------::*/
/* Abaissement graduel des bords d'un height field */
/* Inspiration : 'Image_cadre_C' */
/* TODO : build a real unit test */
/* TODO : expliquer les parametres */
int Image_hf15_sweep(Image_Desc *im, int hfin, int taille, int k)
{
int x, y, x2, y2;
float fhfin, fx, fy, coef, d;
int hit, mess, h, h2;
#if DEBUG_LEVEL
fprintf(stderr, "%s : img=%p hfin=%d taille=%d k=%d\n",
__func__, im, hfin, taille, k);
fprintf(stderr, " pic dims : %d x %d\n", im->width, im->height);
#endif
/* this is really a MESS ! */
fhfin = (float)(hfin*hfin);
x2 = im->width / 2;
y2 = im->height / 2;
#if DEBUG_LEVEL
fprintf(stderr, " fhfin=%f x2=%d y2=%d\n", fhfin, x2, y2);
#endif
hit = mess = 0;
for (y=0; y<im->height; y++)
{
/*
* distance au bord HAUT BAS le plus proche
*/
if (y < y2) fy = (float)y;
else fy = (float)((im->height - y)-1);
fy = fy*fy;
for (x=0; x<im->width; x++)
{
/*
* distance au bord DROITE GAUCHE le plus proche
*/
if (x < x2) fx = (float)x;
else fx = (float)((im->width - x)-1);
fx = fx*fx;
/* XXX un peu plus d'explications ici */
if (fx < fy) d = fx;
else d = fy;
if (d < fhfin)
{
coef = d / fhfin;
h = Image_hf15_height(im, x, y);
h2 = (int)(((float)h*coef) + ((float)hfin*(1.0-coef)));
#if DEBUG_LEVEL > 1
printf("__sweep__ %5d %d\n", h, h2);
#endif
if ( h<0 || h>32767)
{
fprintf(stderr, "%s fail %d %d\n",
__func__, x, y);
abort();
}
Image_hf15_plot(im, x, y, h2);
hit ++;
}
else
{
mess ++;
}
}
}
#if DEBUG_LEVEL
fprintf(stderr, " hit %d mess %d\n", hit, mess);
#endif
return FULL_NUCKED;
}
/*::------------------------------------------------------------------::*/
int Image_hf15_getmin(Image_Desc *s1, Image_Desc *s2, Image_Desc *d)
{
int x, y, h1, h2;
for (y=0; y<d->height; y++)
{
for (x=0; x<d->width; x++)
{
h1 = Image_hf15_height(s1, x, y);
h2 = Image_hf15_height(s2, x, y);
if (h1 < h2)
Image_hf15_plot(d, x, y, h1);
else
Image_hf15_plot(d, x, y, h2);
}
}
return FULL_NUCKED;
}
/*::------------------------------------------------------------------::*/
int Image_hf15_getmax(Image_Desc *s1, Image_Desc *s2, Image_Desc *d)
{
int x, y, h1, h2;
for (y=0; y<d->height; y++)
{
for (x=0; x<d->width; x++)
{
h1 = Image_hf15_height(s1, x, y);
h2 = Image_hf15_height(s2, x, y);
if (h1 > h2)
Image_hf15_plot(d, x, y, h1);
else
Image_hf15_plot(d, x, y, h2);
}
}
return FULL_NUCKED;
}
/*::------------------------------------------------------------------::*/