+++ /dev/null
-#include "hexagon.h"
-
-#include <math.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <limits.h>
-
-/* constructor function */
-struct HL_hex HL_hex_xy(int x, int y) {
- struct HL_hex h;
- h.x = x;
- h.y = y;
- return h;
-}
-
-int HL_hex_cmp(struct HL_hex const *a, struct HL_hex const *b) {
- if (a->x != b->x) {
- return a->x > b->x ? 1 : -1;
- }
- if (a->y != b->y) {
- return a->y > b->y ? 1 : -1;
- }
- return 0;
-}
-
-int HL_hex_eq(struct HL_hex const *a, struct HL_hex const *b) {
- return a->x == b->x && a->y == b->y;
-}
-
-/*
- * This file is written by Nathan Wagner and dedicated to the public
- * domain
- */
-
-double HL_vertexv[12] = {
- .577350269189625764509148780502, 0.0,
- .288675134594812882254574390251, 0.5,
- -.288675134594812882254574390251, 0.5,
- -.577350269189625764509148780502, 0.0,
- -.288675134594812882254574390251, -0.5,
- .288675134594812882254574390251, -0.5};
-
-double HL_fand[16] = {
- 0.0, 0.0,
- .577350269189625764509148780502, 0.0,
- .288675134594812882254574390251, 0.5,
- -.288675134594812882254574390251, 0.5,
- -.577350269189625764509148780502, 0.0,
- -.288675134594812882254574390251, -0.5,
- .288675134594812882254574390251, -0.5,
- .577350269189625764509148780502, 0.0
-};
-
-double HL_hfand[16] = {
- 0.0, 0.0,
- 0.0, .577350269189625764509148780502,
- 0.5, .288675134594812882254574390251,
- 0.5, -.288675134594812882254574390251,
- 0.0, -.577350269189625764509148780502,
- -0.5, -.288675134594812882254574390251,
- -0.5, .288675134594812882254574390251,
- 0.0, .577350269189625764509148780502
-};
-
-float HL_fanf[16] = {
- 0.0f, 0.0f,
- .577350269189625764509148780502f, 0.0f,
- .288675134594812882254574390251f, 0.5f,
- -.288675134594812882254574390251f, 0.5f,
- -.577350269189625764509148780502f, 0.0f,
- -.288675134594812882254574390251f, -0.5f,
- .288675134594812882254574390251f, -0.5f,
- .577350269189625764509148780502f, 0.0f
-};
-
-float HL_hfanf[16] = {
- 0.0f, 0.0f,
- 0.0f, .577350269189625764509148780502f,
- 0.5f, .288675134594812882254574390251f,
- 0.5f, -.288675134594812882254574390251f,
- 0.0f, -.577350269189625764509148780502f,
- -0.5f, -.288675134594812882254574390251f,
- -0.5f, .288675134594812882254574390251f,
- 0.0f, .577350269189625764509148780502f
-};
-
-/* size of a square that will exactly fit in a hexagon */
-/* 2.0/(1+sqrt(3.0)) */
-double HL_square = .73205080756887729352;
-
-/* these all are for a hex one unit across */
-static double hexptvd[6][2] = {
- {.577350269189625764509148780502, 0.0}, /* 1.0/sqrt3 */
- {.288675134594812882254574390251, 0.5}, /* 0.5/sqrt3 */
- {-.288675134594812882254574390251, 0.5},
- {-.577350269189625764509148780502, 0.0},
- {-.288675134594812882254574390251, -0.5},
- {.288675134594812882254574390251, -0.5}
-};
-
-#if 0
-
-/* TODO how is this related? to the above? */
-static double texptvd[6][2] = {
- {1.154700538379251529018297561004, 0.5}, /* 2.0/sqrt3 */
- {.866025403784438646763723170753, 1.0}, /* 1.5/sqrt3 */
- {.288675134594812882254574390251, 1.0},
- {0.0, 0.5},
- {.288675134594812882254574390251, 0.0},
- {.866025403784438646763723170753, 0.0}
-};
-
-static double hexpthd[6][2] = {
- {0.0, .577350269189625764509148780502},
- {0.5, .288675134594812882254574390251},
- {0.5, -.288675134594812882254574390251},
- {0.0, -.577350269189625764509148780502},
- {-0.5, -.288675134594812882254574390251},
- {-0.5, .288675134594812882254574390251}
-};
-
-#endif
-
-#define RD (180.0 / M_PI)
-/* angle ranges from 0-6 */
-/* distance is 0 at origin, 1.0 at the hex side */
-
-#if 0
- double sqrt3;
-
- sqrt3 = sqrt(3.0);
-
- 1
- /---\
- 2/ \0
- / \
- \ /
- 3\ /5
- \---/
- 4
-
- /\
- 0/ \5
- / \
- | |
- 1| |4
- | |
- \ /
- 2\ /3
- \/
-
-#endif
-
-/* return the polar distance */
-struct HL_point HL_polar(double angle, double distance, double *d) {
- double A, B, C, b;
- struct HL_point pt;
-
-#if 0
- C
- /\
- b / \ a
- / \
- / \
- A -------- B
- c
-
- c = 1 ; fixed, will scale later
- B = 60 ; exterior angle of hextant
- C = 180-B-A = 120-A ; sum of angles of a triangle
- A = function argument ; the polar coordinate we are calculating
- b = c * sin(B) / sin(C) ; law of sines
-
-#endif
- /* convert angle to radians */
- angle = angle * M_PI / 3.0;
-
- /* calculate the distance along the ray to the hex side */
-
- A = fmod(angle, M_PI/3.0); /* constrain to within an equilateral */
- B = M_PI / 3.0;
- C = M_PI - B - A;
-
- b = sin(B) / sin(C);
-
- /* scale for hex one unit from side to side, rather than
- * one unit from center to vertex
- */
-/* b = b * sqrt(3.0) / 2.0 / 2.0; */
- b = b / sqrt(3);
-
- pt.x = distance * b * cos(angle);
- pt.y = distance * b * sin(angle);
-
- if (d) {
- *d = distance * b;
- }
-
- return pt;
-}
-
-void HL_vertices(struct HL_hex hex, double *vc) {
- int i;
- double xc, yc;
- struct HL_point center;
-
- center = HL_hexcenter(hex);
- xc = center.x;
- yc = center.y;
-
- for (i=0; i<6; i++) {
- *vc++ = hexptvd[i][0] + xc;
- *vc++ = hexptvd[i][1] + yc;
- }
- *vc++ = hexptvd[0][0] + xc;
- *vc++ = hexptvd[0][1] + yc;
-}
-
-#if 0
-void HL_trianglefan(int cantor, double *vc) {
- HL_hexcenter(cantor, vc, vc+1);
- HL_vertices(cantor, vc+2);
-}
-#endif
-
-struct HL_point HL_hexcenter(struct HL_hex hex) {
- int x, y;
- struct HL_point center;
- double yc;
-
- double stride = 1.5/sqrt(3.0);
-
- x = hex.x;
- y = hex.y;
-
- center.x = x * stride;
-
- if (x >= 0) yc = y + ((x + 1) % 2) / 2.0 - 0.5;
- if (x < 0) yc = y + ((-x + 1) % 2) / 2.0 - 0.5;
-
- center.y = yc;
-
- return center;
-}
-
-/*
- * This function assumes that the hexes are one unit across, and vertically
- * oriented. If that is not the case, you will need to transform
- * your input coordinates first.
- */
-struct HL_hex HL_bin(double x, double y) {
- return HL_hexbin(1.0, x, y);
-}
-
-struct HL_isohex HL_xy2ijk(struct HL_hex hex) {
- int pi, pj, pk;
- int x, y;
- struct HL_isohex iso;
-
- x = hex.x;
- y = hex.y;
-
- pi = x;
- pj = -y;
-
- if (x < 0) {
- pj = pj + (-x + 1) / 2;
- } else {
- pj = pj - x/2;
- }
- pk = -pi - pj;
-
- iso.i = pi;
- iso.j = pj;
- iso.k = pk;
-
- return iso;
-}
-
-#if 0
-
-static int xy2ijk(int x, int y, int *i, int *j, int *k) {
- int pi, pj, pk;
-
- pi = x;
- pj = -y;
- if (x < 0) {
- pj = pj + (-x + 1) / 2;
- } else {
- pj = pj - x/2;
- }
- pk = -pi - pj;
-
- if (i) *i = pi;
- if (j) *j = pj;
- if (k) *k = pk;
-
- return HL_cantor_xy(x,y);
-}
-static int ijk2xy(int i, int j, int k, int *x, int *y) {
- int px, py;
-
- px = i;
-
- /* py = -j - i/2; */
- py = -j;
-
- if (i < 0) {
- py += (-i + 1)/2;
- } else {
- py -= i/2;
- }
-
- if (x) *x = px;
- if (y) *y = py;
-
- return HL_cantor_xy(px,py);
-}
-
-#endif
-
-struct HL_hex HL_ijk2xy(struct HL_isohex iso) {
- int px, py;
- struct HL_hex xy;
- int i,j;
-
- i = iso.i;
- j = iso.j;
-
- px = i;
-
- /* py = -j - i/2; */
- py = -j;
-
- if (i < 0) {
- py += (-i + 1)/2;
- } else {
- py -= i/2;
- }
-
- xy.x = px;
- xy.y = py;
-
- return xy;
-}
-
-
-static void xy2ijkp(struct HL_hex h, int *ijk) {
- struct HL_isohex iso;
-
- iso = HL_xy2ijk(h);
- ijk[0] = iso.i;
- ijk[1] = iso.j;
- ijk[2] = iso.k;
-}
-
-int HL_distance(struct HL_hex from, struct HL_hex to) {
- int dist = 0, i;;
- int fc[3], tc[3];
-
- xy2ijkp(from, fc);
- xy2ijkp(to, tc);
-
- for (i=0;i<=2;i++) {
- dist += abs(fc[i] - tc[i]);
- }
-
- return dist / 2;
-}
-
-int HL_hexes_within_range(struct HL_hex hex, int range, struct HL_hex *list, int size) {
- int count = 0;
- int i;
-
- if (range == 0) {
- return HL_hexes_at_range(hex, 0, list, size);
- }
-
- for (i=1;i<=range;i++) {
- count += HL_hexes_at_range(hex, i, count > size ? 0 : list+count, size-count);
- }
- return count;
-}
-
-int HL_hexes_at_range(struct HL_hex hex, int range, struct HL_hex *list, int size) {
- int q; /* p and q are count/loop vars */
- struct HL_isohex iso;
-
-
- if (range == 0) {
- if (list) {
- list[0] = hex;
- }
- return 1;
- } else if (range < 0) {
- return 0;
- }
-
- /* TODO don't bother to collect if the list isn't big enough? */
- /* i.e. if (!list || size < range * 6) */
- if (!list || size < 1) return range * 6;
-
- iso = HL_xy2ijk(hex);
-
- iso.i += range;
- iso.k = -iso.i - iso.j;
-
- hex = HL_ijk2xy(iso);
-
- for(q=0; q<size && q < range * 6; q++) {
- list[q] = hex;
- hex = HL_adjhex(hex, q/range+2);
- }
-
- return range * 6;
-}
-
-/* direction 0 is positive X , counter clockwise from there */
-struct HL_hex HL_adjhex(struct HL_hex hex, int dir) {
- int c[3];
- struct HL_isohex iso;
-
- iso = HL_xy2ijk(hex);
- c[0] = iso.i;
- c[1] = iso.j;
- c[2] = iso.k;
-
- switch (dir%6) {
- case 2:
- c[0]--; c[1]++; break;
- case 1:
- c[1]++; c[2]--; break;
- case 0:
- c[0]++; c[2]--; break;
- case 5:
- c[0]++; c[1]--; break;
- case 4:
- c[1]--; c[2]++; break;
- case 3:
- c[0]--; ; c[2]++; break;
- }
-
- iso.i = c[0];
- iso.j = c[1];
- iso.k = c[2];
-
- return HL_ijk2xy(iso);
-}
-
-int HL_adjhexp(struct HL_hex hex, int dir, struct HL_hex *adj) {
- if (adj) {
- *adj = HL_adjhex(hex, dir);
- }
- return dir;
-}
-
-/* Determine if a map with these dimensions will overflow */
-int HL_map_bounds_ok(int xdim, int ydim) {
-
- /* return (x+y) * (x + y + 1) / 2 + y+1; */
-
- if (INT_MAX - xdim - 1 < ydim) return 0;
- if (INT_MAX / (xdim+ydim) < (xdim+ydim+1)) return 0;
- if ( (xdim+ydim) * (xdim+ydim+1) / 2 > INT_MAX - ydim - 1)
- return 0;
-
- return 1;
-}
-
-int HL_map_max_dimension(void) {
- int low, high, try;
-
- low = 1; high = INT_MAX/2;
-
- while (low != high - 1) {
- try = (low + high) / 2;
- if (HL_map_bounds_ok(try,try)) {
- low = try;
- } else {
- high = try;
- }
- }
-
- return low;
-}
-
-struct hex {
- int iso;
- int x, y, z;
-};
-
-/* y *must* be positive down as the xy /iso conversion assumes this */
-static int hex_xy(struct hex *h) {
- if (!h->iso) return 1;
- if (h->x >= 0) {
- h->y = -h->y - (h->x+1)/2;
- } else {
- /* need to round toward -inf, not toward zero, so x-1 */
- h->y = -h->y - h->x/2;
- }
- h->iso = 0;
-
- return 1;
-}
-
-#if 0
-
-static int hex_iso(struct hex *h) {
- if (h->iso) return 1;
-
- if (h->x >= 0) {
- h->y = (-h->y - (h->x+1)/2);
- } else {
- /* need to round toward -inf, not toward zero, so x-1 */
- h->y = (-h->y - (h->x)/2);
- }
-
- h->z = -h->x - h->y;
- h->iso = 1;
- return 1;
-}
-
-#endif
-
-#define COS30 (.866025403784438646763723170752)
-
-struct HL_hex HL_hexbin(double width, double x, double y) {
- double z, rx, ry, rz;
- double abs_dx, abs_dy, abs_dz;
- int ix, iy, iz, s;
- struct hex h;
- struct HL_hex hex;
-
- /*x = x / cos(30 * M_PI / 180.0); */ /* rotated X coord */
- x = x / COS30;
- y = y - x / 2.0; /* adjustment for rotated X */
-
- /* adjust for actual hexwidth */
- x /= width;
- y /= width;
-
- z = -x - y;
-
- ix = rx = floor(x + 0.5);
- iy = ry = floor(y + 0.5);
- iz = rz = floor(z + 0.5);
-
- s = ix + iy + iz;
-
- if (s) {
- abs_dx = fabs(rx - x);
- abs_dy = fabs(ry - y);
- abs_dz = fabs(rz - z);
-
- if (abs_dx >= abs_dy && abs_dx >= abs_dz) {
- ix -= s;
- } else if (abs_dy >= abs_dx && abs_dy >= abs_dz) {
- iy -= s;
- } else {
- iz -= s;
- }
- }
- h.x = ix;
- h.y = iy;
- h.z = iz;
- h.iso = 1;
-
- hex_xy(&h);
-
- hex.x = h.x;
- hex.y = h.y;
-
- return hex;
-}
projects / hexagon / blobdiff