blender-archive/source/blender/blenlib/BLI_polyfill_2d.h

/* SPDX-License-Identifier: GPL-2.0-or-later */

#pragma once

/** \file
 * \ingroup bli
 */

#ifdef __cplusplus
extern "C" {
#endif

struct MemArena;

/**
 * A version of #BLI_polyfill_calc that uses a memory arena to avoid re-allocations.
 */
void BLI_polyfill_calc_arena(const float (*coords)[2],
                             unsigned int coords_num,
                             int coords_sign,
                             unsigned int (*r_tris)[3],

                             struct MemArena *arena);

/**
 * Triangulates the given (convex or concave) simple polygon to a list of triangle vertices.
 *
 * \param coords: 2D coordinates describing vertices of the polygon,
 * in either clockwise or counterclockwise order.
 * \param coords_num: Total points in the array.
 * \param coords_sign: Pass this when we know the sign in advance to avoid extra calculations.
 *
 * \param r_tris: This array is filled in with triangle indices in clockwise order.
 * The length of the array must be `coords_num - 2`.
 * Indices are guaranteed to be assigned to unique triangles, with valid indices,
 * even in the case of degenerate input (self intersecting polygons, zero area ears... etc).
 */
void BLI_polyfill_calc(const float (*coords)[2],
                       unsigned int coords_num,
                       int coords_sign,
                       unsigned int (*r_tris)[3]);

/* default size of polyfill arena */
#define BLI_POLYFILL_ARENA_SIZE MEM_SIZE_OPTIMAL(1 << 14)

#ifdef __cplusplus
}
#endif