FloatImg4PythonBinding/experiment/mnt.c

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2023-04-29 19:29:45 +02:00
/*
* Modeles Numeriques de Terrain
*
*/
#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <stdint.h>
#include "../floatimg.h"
int verbosity;
/* ------------------------------------------------------------------- */
/*
* First try
*/
int brotche_mnt_style(FloatImg *src, FloatImg *dst)
{
int x, y;
int offset;
float z1, z2, z3, z4;
float a, b, c;
float pente;
fprintf(stderr, ">>> %s ( %p %p )\n", __func__, src, dst);
#define W (src->width)
#define DX 1.0
#define DY 1.0
for (y=0; y<(src->height-1); y++) {
for (x=0; x<(src->width-1); x++) {
offset = (y * src->width) + x;
z1 = src->R[offset];
z2 = src->R[offset+1];
z3 = src->R[offset+W];
z4 = src->R[offset+W+1];
a = ( z1 + z2 + z3 + z4) / 4.0;
b = (-z1 + z2 - z3 + z4) / 2.0 / DX;
c = (-z1 - z2 + z3 + z4) / 2.0 / DY;
pente = atanf(sqrt(b*b + c*c));
dst->R[offset] = 0;
if (pente < 0.0) dst->G[offset] = pente;
else dst->B[offset] = pente;
}
}
return 0;
}
/* ------------------------------------------------------------------- */
int main(int argc, char *argv[])
{
FloatImg src, dst;
char *infile, *outfile;
int foo;
if (3 != argc) {
fprintf(stderr, "%s need 2 args : infile & outfile\n", argv[0]);
fimg_print_version(0);
exit(1);
}
infile = argv[1]; outfile = argv[2];
fprintf(stderr,"--- working on %s\n", infile);
foo = fimg_create_from_dump(infile, &src);
if (foo) {
fprintf(stderr, "err %d loading image '%s'\n", foo, infile);
exit(1);
}
foo = fimg_clone(&src, &dst, 0);
if (foo) {
fprintf(stderr, "err %d cloning image\n", foo);
exit(1);
}
foo = brotche_mnt_style(&src, &dst);
if (foo) {
fprintf(stderr, "something weird happen %d\n", foo);
exit(1);
}
foo = fimg_export_picture(&dst, outfile, 0);
if (foo) {
fprintf(stderr, "err %d exporting to %s\n", foo, outfile);
exit(1);
}
return 0;
}
/* ------------------------------------------------------------------- */