g->edges = NULL;
g->dots = NULL;
g->num_faces = g->num_edges = g->num_dots = 0;
- g->middle_face = NULL;
g->refcount = 1;
g->lowest_x = g->lowest_y = g->highest_x = g->highest_y = 0;
return g;
* Returns the nearest edge, or NULL if no edge is reasonably
* near the position.
*
- * This algorithm is nice and generic, and doesn't depend on any particular
- * geometric layout of the grid:
- * Start at any dot (pick one next to middle_face).
- * Walk along a path by choosing, from all nearby dots, the one that is
- * nearest the target (x,y). Hopefully end up at the dot which is closest
- * to (x,y). Should work, as long as faces aren't too badly shaped.
- * Then examine each edge around this dot, and pick whichever one is
- * closest (perpendicular distance) to (x,y).
- * Using perpendicular distance is not quite right - the edge might be
- * "off to one side". So we insist that the triangle with (x,y) has
- * acute angles at the edge's dots.
+ * Just judging edges by perpendicular distance is not quite right -
+ * the edge might be "off to one side". So we insist that the triangle
+ * with (x,y) has acute angles at the edge's dots.
*
* edge1
* *---------*------
*/
grid_edge *grid_nearest_edge(grid *g, int x, int y)
{
- grid_dot *cur;
grid_edge *best_edge;
double best_distance = 0;
int i;
- cur = g->middle_face->dots[0];
-
- for (;;) {
- /* Target to beat */
- long dist = SQ((long)cur->x - (long)x) + SQ((long)cur->y - (long)y);
- /* Look for nearer dot - if found, store in 'new'. */
- grid_dot *new = cur;
- int i;
- /* Search all dots in all faces touching this dot. Some shapes
- * (such as in Cairo) don't quite work properly if we only search
- * the dot's immediate neighbours. */
- for (i = 0; i < cur->order; i++) {
- grid_face *f = cur->faces[i];
- int j;
- if (!f) continue;
- for (j = 0; j < f->order; j++) {
- long new_dist;
- grid_dot *d = f->dots[j];
- if (d == cur) continue;
- new_dist = SQ((long)d->x - (long)x) + SQ((long)d->y - (long)y);
- if (new_dist < dist) { /* found closer dot */
- new = d;
- dist = new_dist;
- }
- }
- }
-
- if (new == cur) {
- /* Didn't find a closer dot among the neighbours of 'cur' */
- break;
- } else {
- cur = new;
- }
- }
- /* 'cur' is nearest dot, so find which of the dot's edges is closest. */
best_edge = NULL;
- for (i = 0; i < cur->order; i++) {
- grid_edge *e = cur->edges[i];
+ for (i = 0; i < g->num_edges; i++) {
+ grid_edge *e = &g->edges[i];
long e2; /* squared length of edge */
long a2, b2; /* squared lengths of other sides */
double dist;
}
printf("]\n");
}
- printf("Middle face: %d\n", (int)(g->middle_face - g->faces));
}
/* Show the derived grid information, computed by grid_make_consistent */
static void grid_print_derived(grid *g)
freetree234(points);
assert(g->num_faces <= max_faces);
assert(g->num_dots <= max_dots);
- g->middle_face = g->faces + (height/2) * width + (width/2);
grid_make_consistent(g);
return g;
freetree234(points);
assert(g->num_faces <= max_faces);
assert(g->num_dots <= max_dots);
- g->middle_face = g->faces + (height/2) * width + (width/2);
grid_make_consistent(g);
return g;
}
}
- /* "+ width" takes us to the middle of the row, because each row has
- * (2*width) faces. */
- g->middle_face = g->faces + (height / 2) * 2 * width + width;
-
grid_make_consistent(g);
return g;
}
freetree234(points);
assert(g->num_faces <= max_faces);
assert(g->num_dots <= max_dots);
- g->middle_face = g->faces + (height/2) * width + (width/2);
grid_make_consistent(g);
return g;
freetree234(points);
assert(g->num_faces <= max_faces);
assert(g->num_dots <= max_dots);
- g->middle_face = g->faces + (height/2) * width + (width/2);
grid_make_consistent(g);
return g;
freetree234(points);
assert(g->num_faces <= max_faces);
assert(g->num_dots <= max_dots);
- g->middle_face = g->faces + (height/2) * width + (width/2);
grid_make_consistent(g);
return g;
freetree234(points);
assert(g->num_faces <= max_faces);
assert(g->num_dots <= max_dots);
- g->middle_face = g->faces + (height/2) * width + (width/2);
grid_make_consistent(g);
return g;
freetree234(points);
assert(g->num_faces <= max_faces);
assert(g->num_dots <= max_dots);
- g->middle_face = g->faces + 6 * ((height/2) * width + (width/2));
grid_make_consistent(g);
return g;
freetree234(points);
assert(g->num_faces <= max_faces);
assert(g->num_dots <= max_dots);
- g->middle_face = g->faces + 6 * ((height/2) * width + (width/2));
+
+ grid_make_consistent(g);
+ return g;
+}
+
+grid *grid_new_dodecagonal(int width, int height)
+{
+ int x, y;
+ /* Vector for side of triangle - ratio is close to sqrt(3) */
+ int a = 15;
+ int b = 26;
+
+ /* Upper bounds - don't have to be exact */
+ int max_faces = 3 * width * height;
+ int max_dots = 14 * width * height;
+
+ tree234 *points;
+
+ grid *g = grid_new();
+ g->tilesize = b;
+ g->faces = snewn(max_faces, grid_face);
+ g->dots = snewn(max_dots, grid_dot);
+
+ points = newtree234(grid_point_cmp_fn);
+
+ for (y = 0; y < height; y++) {
+ for (x = 0; x < width; x++) {
+ grid_dot *d;
+ /* centre of dodecagon */
+ int px = (4*a + 2*b) * x;
+ int py = (3*a + 2*b) * y;
+ if (y % 2)
+ px += 2*a + b;
+
+ /* dodecagon */
+ grid_face_add_new(g, 12);
+ d = grid_get_dot(g, points, px + ( a ), py - (2*a + b)); grid_face_set_dot(g, d, 0);
+ d = grid_get_dot(g, points, px + ( a + b), py - ( a + b)); grid_face_set_dot(g, d, 1);
+ d = grid_get_dot(g, points, px + (2*a + b), py - ( a )); grid_face_set_dot(g, d, 2);
+ d = grid_get_dot(g, points, px + (2*a + b), py + ( a )); grid_face_set_dot(g, d, 3);
+ d = grid_get_dot(g, points, px + ( a + b), py + ( a + b)); grid_face_set_dot(g, d, 4);
+ d = grid_get_dot(g, points, px + ( a ), py + (2*a + b)); grid_face_set_dot(g, d, 5);
+ d = grid_get_dot(g, points, px - ( a ), py + (2*a + b)); grid_face_set_dot(g, d, 6);
+ d = grid_get_dot(g, points, px - ( a + b), py + ( a + b)); grid_face_set_dot(g, d, 7);
+ d = grid_get_dot(g, points, px - (2*a + b), py + ( a )); grid_face_set_dot(g, d, 8);
+ d = grid_get_dot(g, points, px - (2*a + b), py - ( a )); grid_face_set_dot(g, d, 9);
+ d = grid_get_dot(g, points, px - ( a + b), py - ( a + b)); grid_face_set_dot(g, d, 10);
+ d = grid_get_dot(g, points, px - ( a ), py - (2*a + b)); grid_face_set_dot(g, d, 11);
+
+ /* triangle below dodecagon */
+ if ((y < height - 1 && (x < width - 1 || !(y % 2)) && (x > 0 || (y % 2)))) {
+ grid_face_add_new(g, 3);
+ d = grid_get_dot(g, points, px + a, py + (2*a + b)); grid_face_set_dot(g, d, 0);
+ d = grid_get_dot(g, points, px , py + (2*a + 2*b)); grid_face_set_dot(g, d, 1);
+ d = grid_get_dot(g, points, px - a, py + (2*a + b)); grid_face_set_dot(g, d, 2);
+ }
+
+ /* triangle above dodecagon */
+ if ((y && (x < width - 1 || !(y % 2)) && (x > 0 || (y % 2)))) {
+ grid_face_add_new(g, 3);
+ d = grid_get_dot(g, points, px - a, py - (2*a + b)); grid_face_set_dot(g, d, 0);
+ d = grid_get_dot(g, points, px , py - (2*a + 2*b)); grid_face_set_dot(g, d, 1);
+ d = grid_get_dot(g, points, px + a, py - (2*a + b)); grid_face_set_dot(g, d, 2);
+ }
+ }
+ }
+
+ freetree234(points);
+ assert(g->num_faces <= max_faces);
+ assert(g->num_dots <= max_dots);
+
+ grid_make_consistent(g);
+ return g;
+}
+
+grid *grid_new_greatdodecagonal(int width, int height)
+{
+ int x, y;
+ /* Vector for side of triangle - ratio is close to sqrt(3) */
+ int a = 15;
+ int b = 26;
+
+ /* Upper bounds - don't have to be exact */
+ int max_faces = 30 * width * height;
+ int max_dots = 200 * width * height;
+
+ tree234 *points;
+
+ grid *g = grid_new();
+ g->tilesize = b;
+ g->faces = snewn(max_faces, grid_face);
+ g->dots = snewn(max_dots, grid_dot);
+
+ points = newtree234(grid_point_cmp_fn);
+
+ for (y = 0; y < height; y++) {
+ for (x = 0; x < width; x++) {
+ grid_dot *d;
+ /* centre of dodecagon */
+ int px = (6*a + 2*b) * x;
+ int py = (3*a + 3*b) * y;
+ if (y % 2)
+ px += 3*a + b;
+
+ /* dodecagon */
+ grid_face_add_new(g, 12);
+ d = grid_get_dot(g, points, px + ( a ), py - (2*a + b)); grid_face_set_dot(g, d, 0);
+ d = grid_get_dot(g, points, px + ( a + b), py - ( a + b)); grid_face_set_dot(g, d, 1);
+ d = grid_get_dot(g, points, px + (2*a + b), py - ( a )); grid_face_set_dot(g, d, 2);
+ d = grid_get_dot(g, points, px + (2*a + b), py + ( a )); grid_face_set_dot(g, d, 3);
+ d = grid_get_dot(g, points, px + ( a + b), py + ( a + b)); grid_face_set_dot(g, d, 4);
+ d = grid_get_dot(g, points, px + ( a ), py + (2*a + b)); grid_face_set_dot(g, d, 5);
+ d = grid_get_dot(g, points, px - ( a ), py + (2*a + b)); grid_face_set_dot(g, d, 6);
+ d = grid_get_dot(g, points, px - ( a + b), py + ( a + b)); grid_face_set_dot(g, d, 7);
+ d = grid_get_dot(g, points, px - (2*a + b), py + ( a )); grid_face_set_dot(g, d, 8);
+ d = grid_get_dot(g, points, px - (2*a + b), py - ( a )); grid_face_set_dot(g, d, 9);
+ d = grid_get_dot(g, points, px - ( a + b), py - ( a + b)); grid_face_set_dot(g, d, 10);
+ d = grid_get_dot(g, points, px - ( a ), py - (2*a + b)); grid_face_set_dot(g, d, 11);
+
+ /* hexagon below dodecagon */
+ if (y < height - 1 && (x < width - 1 || !(y % 2)) && (x > 0 || (y % 2))) {
+ grid_face_add_new(g, 6);
+ d = grid_get_dot(g, points, px + a, py + (2*a + b)); grid_face_set_dot(g, d, 0);
+ d = grid_get_dot(g, points, px + 2*a, py + (2*a + 2*b)); grid_face_set_dot(g, d, 1);
+ d = grid_get_dot(g, points, px + a, py + (2*a + 3*b)); grid_face_set_dot(g, d, 2);
+ d = grid_get_dot(g, points, px - a, py + (2*a + 3*b)); grid_face_set_dot(g, d, 3);
+ d = grid_get_dot(g, points, px - 2*a, py + (2*a + 2*b)); grid_face_set_dot(g, d, 4);
+ d = grid_get_dot(g, points, px - a, py + (2*a + b)); grid_face_set_dot(g, d, 5);
+ }
+
+ /* hexagon above dodecagon */
+ if (y && (x < width - 1 || !(y % 2)) && (x > 0 || (y % 2))) {
+ grid_face_add_new(g, 6);
+ d = grid_get_dot(g, points, px - a, py - (2*a + b)); grid_face_set_dot(g, d, 0);
+ d = grid_get_dot(g, points, px - 2*a, py - (2*a + 2*b)); grid_face_set_dot(g, d, 1);
+ d = grid_get_dot(g, points, px - a, py - (2*a + 3*b)); grid_face_set_dot(g, d, 2);
+ d = grid_get_dot(g, points, px + a, py - (2*a + 3*b)); grid_face_set_dot(g, d, 3);
+ d = grid_get_dot(g, points, px + 2*a, py - (2*a + 2*b)); grid_face_set_dot(g, d, 4);
+ d = grid_get_dot(g, points, px + a, py - (2*a + b)); grid_face_set_dot(g, d, 5);
+ }
+
+ /* square on right of dodecagon */
+ if (x < width - 1) {
+ grid_face_add_new(g, 4);
+ d = grid_get_dot(g, points, px + 2*a + b, py - a); grid_face_set_dot(g, d, 0);
+ d = grid_get_dot(g, points, px + 4*a + b, py - a); grid_face_set_dot(g, d, 1);
+ d = grid_get_dot(g, points, px + 4*a + b, py + a); grid_face_set_dot(g, d, 2);
+ d = grid_get_dot(g, points, px + 2*a + b, py + a); grid_face_set_dot(g, d, 3);
+ }
+
+ /* square on top right of dodecagon */
+ if (y && (x < width - 1 || !(y % 2))) {
+ grid_face_add_new(g, 4);
+ d = grid_get_dot(g, points, px + ( a ), py - (2*a + b)); grid_face_set_dot(g, d, 0);
+ d = grid_get_dot(g, points, px + (2*a ), py - (2*a + 2*b)); grid_face_set_dot(g, d, 1);
+ d = grid_get_dot(g, points, px + (2*a + b), py - ( a + 2*b)); grid_face_set_dot(g, d, 2);
+ d = grid_get_dot(g, points, px + ( a + b), py - ( a + b)); grid_face_set_dot(g, d, 3);
+ }
+
+ /* square on top left of dodecagon */
+ if (y && (x || (y % 2))) {
+ grid_face_add_new(g, 4);
+ d = grid_get_dot(g, points, px - ( a + b), py - ( a + b)); grid_face_set_dot(g, d, 0);
+ d = grid_get_dot(g, points, px - (2*a + b), py - ( a + 2*b)); grid_face_set_dot(g, d, 1);
+ d = grid_get_dot(g, points, px - (2*a ), py - (2*a + 2*b)); grid_face_set_dot(g, d, 2);
+ d = grid_get_dot(g, points, px - ( a ), py - (2*a + b)); grid_face_set_dot(g, d, 3);
+ }
+ }
+ }
+
+ freetree234(points);
+ assert(g->num_faces <= max_faces);
+ assert(g->num_dots <= max_dots);
grid_make_consistent(g);
return g;
~mdw / sgt / puzzles / blobdiff