// Calculates the distance between two GPS lat/lon coordinates
// returns units: KM
// From: http://www.movable-type.co.uk/scripts/latlong.html
sll DistanceBetweenSLL(sll lat1, sll lon1, sll lat2, sll lon2) {
sll R = int2sll(6371); // kilometres
sll lat1_rad = slldeg2rad(lat1);
sll lon1_rad = slldeg2rad(lon1);
sll lat2_rad = slldeg2rad(lat2);
sll lon2_rad = slldeg2rad(lon2);
sll dist_lat = sllsub(lat2_rad, lat1_rad);
sll dist_lon = sllsub(lon2_rad, lon1_rad);
dist_lat = slldiv2(dist_lat);
dist_lon = slldiv2(dist_lon);
dist_lat = sllsin(dist_lat);
dist_lon = sllsin(dist_lon);
sll a = sllmul(dist_lat, dist_lat);
sll b = sllmul(dist_lon, dist_lon);
sll c = sllmul(sllcos(lat1_rad), sllcos(lat2_rad));
sll d = slladd(a, sllmul(b,c));
sll d_sqrt = sllsqrt(d);
sll d_sqrt_1 = sllsqrt(sllsub(CONST_1,d));
sll result = sllmul2(sllatan2(d_sqrt, d_sqrt_1));
return sllmul(R,result);
}
int gl_V3_Norm(V3 *a)
{
GLfloat n;
n=sllsqrt(slladd(slladd(sllmul(a->X,a->X), sllmul(a->Y,a->Y)), sllmul(a->Z,a->Z)));
if (sllvalue(n)==sllvalue(int2sll(0))) return 1;
a->X=slldiv(a->X, n);
a->Y=slldiv(a->Y, n);
a->Z=slldiv(a->Z, n);
return 0;
}
void glopRotate(GLContext *c,GLParam *p)
{
#define SLL_M_PI dbl2sll(M_PI)
M4 m;
GLfloat u[3];
GLfloat angle;
int dir_code;
angle = slldiv(sllmul(p[1].f, SLL_M_PI), int2sll(180));
u[0]=p[2].f;
u[1]=p[3].f;
u[2]=p[4].f;
/* simple case detection */
dir_code = ((sllvalue(u[0]) != sllvalue(int2sll(0)))<<2) | ((sllvalue(u[1]) != sllvalue(int2sll(0)))<<1) | (sllvalue(u[2]) != sllvalue(int2sll(0)));
switch(dir_code) {
case 0:
gl_M4_Id(&m);
break;
case 4:
if (sllvalue(u[0]) < sllvalue(int2sll(0))) angle=sllneg(angle);
gl_M4_Rotate(&m,angle,0);
break;
case 2:
if (sllvalue(u[1]) < sllvalue(int2sll(0))) angle=sllneg(angle);
gl_M4_Rotate(&m,angle,1);
break;
case 1:
if (sllvalue(u[2]) < sllvalue(int2sll(0))) angle=sllneg(angle);
gl_M4_Rotate(&m,angle,2);
break;
default:
{
GLfloat cost, sint;
/* normalize vector */
GLfloat len = slladd(
slladd(
sllmul(u[0],u[0]),
sllmul(u[1],u[1])
),
sllmul(u[2],u[2]));
if (sllvalue(len) == sllvalue(int2sll(0))) return;
len = slldiv(int2sll(1), sllsqrt(len));
u[0] = sllmul(u[0], len);
u[1] = sllmul(u[1], len);
u[2] = sllmul(u[2], len);
/* store cos and sin values */
cost=sllcos(angle);
sint=sllsin(angle);
/* fill in the values */
m.m[3][0]=m.m[3][1]=m.m[3][2]=
m.m[0][3]=m.m[1][3]=m.m[2][3]=int2sll(0);
m.m[3][3]=int2sll(1);
/* do the math */
m.m[0][0]=slladd(sllmul(u[0],u[0]), sllmul(cost, sllsub(int2sll(1), sllmul(u[0],u[0]))));
m.m[1][0]=sllsub(sllmul(sllmul(u[0],u[1]), sllsub(int2sll(1), cost)), sllmul(u[2],sint));
m.m[2][0]=slladd(sllmul(sllmul(u[2],u[0]), sllsub(int2sll(1), cost)), sllmul(u[1],sint));
m.m[0][1]=slladd(sllmul(sllmul(u[0],u[1]), sllsub(int2sll(1), cost)), sllmul(u[2],sint));
m.m[1][1]=slladd(sllmul(u[1],u[1]), sllmul(cost, sllsub(int2sll(1), sllmul(u[1],u[1]))));
m.m[2][1]=sllsub(sllmul(sllmul(u[1],u[2]), sllsub(int2sll(1), cost)), sllmul(u[0],sint));
m.m[0][2]=sllsub(sllmul(sllmul(u[2],u[0]), sllsub(int2sll(1), cost)), sllmul(u[1],sint));
m.m[1][2]=slladd(sllmul(sllmul(u[1],u[2]), sllsub(int2sll(1), cost)), sllmul(u[0],sint));
m.m[2][2]=slladd(sllmul(u[2],u[2]), sllmul(cost, sllsub(int2sll(1), sllmul(u[2],u[2]))));
}
}
gl_M4_MulLeft(c->matrix_stack_ptr[c->matrix_mode],&m);
gl_matrix_update(c);
}
