void
clip_line(struct item_bin *ib, struct rect *r, struct tile_parameter *param, struct item_bin_sink *out)
{
char *buffer=g_alloca(sizeof(char)*(ib->len*4+32));
struct item_bin *ib_new=(struct item_bin *)buffer;
struct coord *pa=(struct coord *)(ib+1);
int count=ib->clen/2;
struct coord p1,p2;
int i,code;
item_bin_init(ib_new, ib->type);
for (i = 0 ; i < count ; i++) {
if (i) {
p1.x=pa[i-1].x;
p1.y=pa[i-1].y;
p2.x=pa[i].x;
p2.y=pa[i].y;
/* 0 = invisible, 1 = completely visible, 3 = start point clipped, 5 = end point clipped, 7 both points clipped */
code=geom_clip_line_code(&p1, &p2, r);
#if 1
if (((code == 1 || code == 5) && ib_new->clen == 0) || (code & 2)) {
item_bin_add_coord(ib_new, &p1, 1);
}
if (code) {
item_bin_add_coord(ib_new, &p2, 1);
}
if (i == count-1 || (code & 4)) {
if (param->attr_to_copy)
item_bin_copy_attr(ib_new, ib, param->attr_to_copy);
if (ib_new->clen)
item_bin_write_clipped(ib_new, param, out);
item_bin_init(ib_new, ib->type);
}
#else
if (code) {
item_bin_init(ib_new, ib->type);
item_bin_add_coord(ib_new, &p1, 1);
item_bin_add_coord(ib_new, &p2, 1);
if (param->attr_to_copy)
item_bin_copy_attr(ib_new, ib, param->attr_to_copy);
item_bin_write_clipped(ib_new, param, out);
}
#endif
}
}
}
static int
coastline_processor_process(struct item_bin_sink_func *func, struct item_bin *ib, struct tile_data *tile_data)
{
#if 0
int i;
struct coord *c=(struct coord *)(ib+1);
for (i = 0 ; i < 19 ; i++) {
c[i]=c[i+420];
}
ib->clen=(i-1)*2;
#endif
item_bin_write_clipped(ib, func->priv_data[0], func->priv_data[1]);
return 0;
}
void
clip_polygon(struct item_bin *ib, struct rect *r, struct tile_parameter *param, struct item_bin_sink *out)
{
int count_in=ib->clen/2;
struct coord *pin,*p,*s,pi;
char *buffer1=g_alloca(sizeof(char)*(ib->len*4+ib->clen*7+32));
struct item_bin *ib1=(struct item_bin *)buffer1;
char *buffer2=g_alloca(sizeof(char)*(ib->len*4+ib->clen*7+32));
struct item_bin *ib2=(struct item_bin *)buffer2;
struct item_bin *ib_in,*ib_out;
int edge,i;
ib_out=ib1;
ib_in=ib;
for (edge = 0 ; edge < 4 ; edge++) {
count_in=ib_in->clen/2;
pin=(struct coord *)(ib_in+1);
p=pin;
s=pin+count_in-1;
item_bin_init(ib_out, ib_in->type);
for (i = 0 ; i < count_in ; i++) {
if (geom_is_inside(p, r, edge)) {
if (! geom_is_inside(s, r, edge)) {
geom_poly_intersection(s,p,r,edge,&pi);
item_bin_add_coord(ib_out, &pi, 1);
}
item_bin_add_coord(ib_out, p, 1);
} else {
if (geom_is_inside(s, r, edge)) {
geom_poly_intersection(p,s,r,edge,&pi);
item_bin_add_coord(ib_out, &pi, 1);
}
}
s=p;
p++;
}
if (ib_in == ib1) {
ib_in=ib2;
ib_out=ib1;
} else {
ib_in=ib1;
ib_out=ib2;
}
}
if (ib_in->clen) {
if (param->attr_to_copy)
item_bin_copy_attr(ib_in, ib, param->attr_to_copy);
item_bin_write_clipped(ib_in, param, out);
}
}
