void um_init(um *u, long length, unsigned char *buffer) {
int i;
u->r[0] = 0;
u->r[1] = 0;
u->r[2] = 0;
u->r[3] = 0;
u->r[4] = 0;
u->r[5] = 0;
u->r[6] = 0;
u->r[7] = 0;
u->finger = 0;
u->arrays = 1;
u->a = malloc(sizeof(array)*u->arrays);
u->a[0].id = 0;
u->a[0].length = length;
u->a[0].elt = malloc(length*sizeof(platter));//buffer;
// portable endian handling thanks to http://commandcenter.blogspot.co.uk/2012/04/byte-order-fallacy.html
#define LITTLE(a,b,c,d) (a<<0)|(b<<8)|(c<<16)|(d<<24)
#define BIG(a,b,c,d) (a<<24)|(b<<16)|(c<<8)|(d<<0)
for(i = 0; i < length; i++) {
u->a[0].elt[i] = BIG(buffer[4*i+0],buffer[4*i+1],buffer[4*i+2],buffer[4*i+3]);
}
}
inline void ft_resalpha(t_color *c, t_color bg)
{
t_big delta;
if (INVI(*c))
{
*c = bg;
return ;
}
delta = BIG(c->b.a) / 255;
c->b.a = 255;
c->b.r = ft_mix(c->b.r, bg.b.r, delta);
c->b.g = ft_mix(c->b.g, bg.b.g, delta);
c->b.b = ft_mix(c->b.b, bg.b.b, delta);
}
