int vec_y = TRIANGLE_VEC_Y;
*tilesize = TRIANGLE_TILESIZE;
- *xextent = width * 2 * vec_x + vec_x;
+ *xextent = (width+1) * 2 * vec_x;
*yextent = height * vec_y;
}
+static char *grid_validate_desc_triangular(grid_type type, int width,
+ int height, char *desc)
+{
+ /*
+ * Triangular grids: an absent description is valid (indicating
+ * the old-style approach which had 'ears', i.e. triangles
+ * connected to only one other face, at some grid corners), and so
+ * is a description reading just "0" (indicating the new-style
+ * approach in which those ears are trimmed off). Anything else is
+ * illegal.
+ */
+
+ if (!desc || !strcmp(desc, "0"))
+ return NULL;
+
+ return "Unrecognised grid description.";
+}
+
/* Doesn't use the previous method of generation, it pre-dates it!
* A triangular grid is just about simple enough to do by "brute force" */
static grid *grid_new_triangular(int width, int height, char *desc)
{
int x,y;
+ int version = (desc == NULL ? -1 : atoi(desc));
/* Vector for side of triangle - ratio is close to sqrt(3) */
int vec_x = TRIANGLE_VEC_X;
grid *g = grid_empty();
g->tilesize = TRIANGLE_TILESIZE;
- g->num_faces = width * height * 2;
- g->num_dots = (width + 1) * (height + 1);
- g->faces = snewn(g->num_faces, grid_face);
- g->dots = snewn(g->num_dots, grid_dot);
-
- /* generate dots */
- index = 0;
- for (y = 0; y <= height; y++) {
- for (x = 0; x <= width; x++) {
- grid_dot *d = g->dots + index;
- /* odd rows are offset to the right */
- d->order = 0;
- d->edges = NULL;
- d->faces = NULL;
- d->x = x * 2 * vec_x + ((y % 2) ? vec_x : 0);
- d->y = y * vec_y;
- index++;
+ if (version == -1) {
+ /*
+ * Old-style triangular grid generation, preserved as-is for
+ * backwards compatibility with old game ids, in which it's
+ * just a little asymmetric and there are 'ears' (faces linked
+ * to only one other face) at two grid corners.
+ *
+ * Example old-style game ids, which should still work, and in
+ * which you should see the ears in the TL/BR corners on the
+ * first one and in the TL/BL corners on the second:
+ *
+ * 5x5t1:2c2a1a2a201a1a1a1112a1a2b1211f0b21a2a2a0a
+ * 5x6t1:a022a212h1a1d1a12c2b11a012b1a20d1a0a12e
+ */
+
+ g->num_faces = width * height * 2;
+ g->num_dots = (width + 1) * (height + 1);
+ g->faces = snewn(g->num_faces, grid_face);
+ g->dots = snewn(g->num_dots, grid_dot);
+
+ /* generate dots */
+ index = 0;
+ for (y = 0; y <= height; y++) {
+ for (x = 0; x <= width; x++) {
+ grid_dot *d = g->dots + index;
+ /* odd rows are offset to the right */
+ d->order = 0;
+ d->edges = NULL;
+ d->faces = NULL;
+ d->x = x * 2 * vec_x + ((y % 2) ? vec_x : 0);
+ d->y = y * vec_y;
+ index++;
+ }
}
- }
- /* generate faces */
- index = 0;
- for (y = 0; y < height; y++) {
- for (x = 0; x < width; x++) {
- /* initialise two faces for this (x,y) */
- grid_face *f1 = g->faces + index;
- grid_face *f2 = f1 + 1;
- f1->edges = NULL;
- f1->order = 3;
- f1->dots = snewn(f1->order, grid_dot*);
- f1->has_incentre = FALSE;
- f2->edges = NULL;
- f2->order = 3;
- f2->dots = snewn(f2->order, grid_dot*);
- f2->has_incentre = FALSE;
-
- /* face descriptions depend on whether the row-number is
- * odd or even */
+ /* generate faces */
+ index = 0;
+ for (y = 0; y < height; y++) {
+ for (x = 0; x < width; x++) {
+ /* initialise two faces for this (x,y) */
+ grid_face *f1 = g->faces + index;
+ grid_face *f2 = f1 + 1;
+ f1->edges = NULL;
+ f1->order = 3;
+ f1->dots = snewn(f1->order, grid_dot*);
+ f1->has_incentre = FALSE;
+ f2->edges = NULL;
+ f2->order = 3;
+ f2->dots = snewn(f2->order, grid_dot*);
+ f2->has_incentre = FALSE;
+
+ /* face descriptions depend on whether the row-number is
+ * odd or even */
+ if (y % 2) {
+ f1->dots[0] = g->dots + y * w + x;
+ f1->dots[1] = g->dots + (y + 1) * w + x + 1;
+ f1->dots[2] = g->dots + (y + 1) * w + x;
+ f2->dots[0] = g->dots + y * w + x;
+ f2->dots[1] = g->dots + y * w + x + 1;
+ f2->dots[2] = g->dots + (y + 1) * w + x + 1;
+ } else {
+ f1->dots[0] = g->dots + y * w + x;
+ f1->dots[1] = g->dots + y * w + x + 1;
+ f1->dots[2] = g->dots + (y + 1) * w + x;
+ f2->dots[0] = g->dots + y * w + x + 1;
+ f2->dots[1] = g->dots + (y + 1) * w + x + 1;
+ f2->dots[2] = g->dots + (y + 1) * w + x;
+ }
+ index += 2;
+ }
+ }
+ } else {
+ /*
+ * New-style approach, in which there are never any 'ears',
+ * and if height is even then the grid is nicely 4-way
+ * symmetric.
+ *
+ * Example new-style grids:
+ *
+ * 5x5t1:0_21120b11a1a01a1a00c1a0b211021c1h1a2a1a0a
+ * 5x6t1:0_a1212c22c2a02a2f22a0c12a110d0e1c0c0a101121a1
+ */
+ tree234 *points = newtree234(grid_point_cmp_fn);
+ /* Upper bounds - don't have to be exact */
+ int max_faces = height * (2*width+1);
+ int max_dots = (height+1) * (width+1) * 4;
+
+ g->faces = snewn(max_faces, grid_face);
+ g->dots = snewn(max_dots, grid_dot);
+
+ for (y = 0; y < height; y++) {
+ /*
+ * Each row contains (width+1) triangles one way up, and
+ * (width) triangles the other way up. Which way up is
+ * which varies with parity of y. Also, the dots around
+ * each face will flip direction with parity of y, so we
+ * set up n1 and n2 to cope with that easily.
+ */
+ int y0, y1, n1, n2;
+ y0 = y1 = y * vec_y;
if (y % 2) {
- f1->dots[0] = g->dots + y * w + x;
- f1->dots[1] = g->dots + (y + 1) * w + x + 1;
- f1->dots[2] = g->dots + (y + 1) * w + x;
- f2->dots[0] = g->dots + y * w + x;
- f2->dots[1] = g->dots + y * w + x + 1;
- f2->dots[2] = g->dots + (y + 1) * w + x + 1;
+ y1 += vec_y;
+ n1 = 2; n2 = 1;
} else {
- f1->dots[0] = g->dots + y * w + x;
- f1->dots[1] = g->dots + y * w + x + 1;
- f1->dots[2] = g->dots + (y + 1) * w + x;
- f2->dots[0] = g->dots + y * w + x + 1;
- f2->dots[1] = g->dots + (y + 1) * w + x + 1;
- f2->dots[2] = g->dots + (y + 1) * w + x;
+ y0 += vec_y;
+ n1 = 1; n2 = 2;
+ }
+
+ for (x = 0; x <= width; x++) {
+ int x0 = 2*x * vec_x, x1 = x0 + vec_x, x2 = x1 + vec_x;
+
+ /*
+ * If the grid has odd height, then we skip the first
+ * and last triangles on this row, otherwise they'll
+ * end up as ears.
+ */
+ if (height % 2 == 1 && y == height-1 && (x == 0 || x == width))
+ continue;
+
+ grid_face_add_new(g, 3);
+ grid_face_set_dot(g, grid_get_dot(g, points, x0, y0), 0);
+ grid_face_set_dot(g, grid_get_dot(g, points, x1, y1), n1);
+ grid_face_set_dot(g, grid_get_dot(g, points, x2, y0), n2);
+ }
+
+ for (x = 0; x < width; x++) {
+ int x0 = (2*x+1) * vec_x, x1 = x0 + vec_x, x2 = x1 + vec_x;
+
+ grid_face_add_new(g, 3);
+ grid_face_set_dot(g, grid_get_dot(g, points, x0, y1), 0);
+ grid_face_set_dot(g, grid_get_dot(g, points, x1, y0), n2);
+ grid_face_set_dot(g, grid_get_dot(g, points, x2, y1), n1);
}
- index += 2;
}
+
+ freetree234(points);
+ assert(g->num_faces <= max_faces);
+ assert(g->num_dots <= max_dots);
}
grid_make_consistent(g);
char *grid_new_desc(grid_type type, int width, int height, random_state *rs)
{
- if (type != GRID_PENROSE_P2 && type != GRID_PENROSE_P3)
+ if (type == GRID_PENROSE_P2 || type == GRID_PENROSE_P3) {
+ return grid_new_desc_penrose(type, width, height, rs);
+ } else if (type == GRID_TRIANGULAR) {
+ return dupstr("0"); /* up-to-date version of triangular grid */
+ } else {
return NULL;
-
- return grid_new_desc_penrose(type, width, height, rs);
+ }
}
char *grid_validate_desc(grid_type type, int width, int height, char *desc)
{
- if (type != GRID_PENROSE_P2 && type != GRID_PENROSE_P3) {
+ if (type == GRID_PENROSE_P2 || type == GRID_PENROSE_P3) {
+ return grid_validate_desc_penrose(type, width, height, desc);
+ } else if (type == GRID_TRIANGULAR) {
+ return grid_validate_desc_triangular(type, width, height, desc);
+ } else {
if (desc != NULL)
return "Grid description strings not used with this grid type";
return NULL;
}
-
- return grid_validate_desc_penrose(type, width, height, desc);
}
grid *grid_new(grid_type type, int width, int height, char *desc)
~ian / sgt-puzzles.git / commitdiff