Files
puzzles/penrose.h
Ben Harris 3c3468355f Use unreserved macro names for multiple-include protection
Some headers used macros named like _THING_H for multiple-include
protection.  That style of name is reserved in ISO C, though, so I've
replaced it with PUZZLES_THING_H which is my favourite of the other
styles in use.
2023-02-18 23:07:44 +00:00

60 lines
1.7 KiB
C

/* penrose.h
*
* Penrose tiling functions.
*
* Provides an interface with which to generate Penrose tilings
* by recursive subdivision of an initial tile of choice (one of the
* four sets of two pairs kite/dart, or thin/thick rhombus).
*
* You supply a callback function and a context pointer, which is
* called with each tile in turn: you choose how many times to recurse.
*/
#ifndef PUZZLES_PENROSE_H
#define PUZZLES_PENROSE_H
#ifndef PHI
#define PHI 1.6180339887
#endif
typedef struct vector vector;
double v_x(vector *vs, int i);
double v_y(vector *vs, int i);
typedef struct penrose_state penrose_state;
/* Return non-zero to clip the tree here (i.e. not recurse
* below this tile).
*
* Parameters are state, vector array, npoints, depth.
* ctx is inside state.
*/
typedef int (*tile_callback)(penrose_state *, vector *, int, int);
struct penrose_state {
int start_size; /* initial side length */
int max_depth; /* Recursion depth */
tile_callback new_tile;
void *ctx; /* for callback */
};
enum { PENROSE_P2, PENROSE_P3 };
extern int penrose(penrose_state *state, int which, int angle);
/* Returns the side-length of a penrose tile at recursion level
* gen, given a starting side length. */
extern double penrose_side_length(double start_size, int depth);
/* Returns the count of each type of tile at a given recursion depth. */
extern void penrose_count_tiles(int gen, int *nlarge, int *nsmall);
/* Calculate start size and recursion depth required to produce a
* width-by-height sized patch of penrose tiles with the given tilesize */
extern void penrose_calculate_size(int which, int tilesize, int w, int h,
double *required_radius, int *start_size, int *depth);
#endif