From 7b09710392d35fb55b52031d447a542d99fc6b4b Mon Sep 17 00:00:00 2001 From: Tavian Barnes Date: Tue, 19 Aug 2014 17:10:03 -0400 Subject: Modularize the libdimension codebase. --- libdimension/pattern/map.c | 126 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 126 insertions(+) create mode 100644 libdimension/pattern/map.c (limited to 'libdimension/pattern/map.c') diff --git a/libdimension/pattern/map.c b/libdimension/pattern/map.c new file mode 100644 index 0000000..ac07960 --- /dev/null +++ b/libdimension/pattern/map.c @@ -0,0 +1,126 @@ +/************************************************************************* + * Copyright (C) 2010-2014 Tavian Barnes * + * * + * This file is part of The Dimension Library. * + * * + * The Dimension Library is free software; you can redistribute it and/ * + * or modify it under the terms of the GNU Lesser General Public License * + * as published by the Free Software Foundation; either version 3 of the * + * License, or (at your option) any later version. * + * * + * The Dimension Library is distributed in the hope that it will be * + * useful, but WITHOUT ANY WARRANTY; without even the implied warranty * + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * + * Lesser General Public License for more details. * + * * + * You should have received a copy of the GNU Lesser General Public * + * License along with this program. If not, see * + * . * + *************************************************************************/ + +/** + * @file + * Generic maps. + */ + +#include "internal.h" +#include "dimension/pattern.h" + +/// dmnsn_map definition. +struct dmnsn_map { + size_t obj_size; ///< @internal The size of the mapped objects. + dmnsn_array *array; ///< @internal The map entries. +}; + +/// An [index, object] pair. +typedef struct dmnsn_map_entry { + double n; + char object[]; +} dmnsn_map_entry; + +dmnsn_map * +dmnsn_new_map(dmnsn_pool *pool, size_t size) +{ + dmnsn_map *map = DMNSN_PALLOC(pool, dmnsn_map); + map->obj_size = size; + map->array = dmnsn_palloc_array(pool, sizeof(dmnsn_map_entry) + size); + return map; +} + +void +dmnsn_map_add_entry(dmnsn_map *map, double n, const void *obj) +{ + dmnsn_map_entry *entry; + DMNSN_ALLOCA(entry, sizeof(dmnsn_map_entry) + map->obj_size); + + entry->n = n; + memcpy(entry->object, obj, map->obj_size); + + // Sorted insertion + size_t i; + for (i = dmnsn_array_size(map->array); i-- > 0;) { + dmnsn_map_entry *other = dmnsn_array_at(map->array, i); + if (other->n <= n) { + break; + } + } + + dmnsn_array_insert(map->array, i + 1, entry); +} + +size_t +dmnsn_map_size(const dmnsn_map *map) +{ + return dmnsn_array_size(map->array); +} + +void +dmnsn_map_evaluate(const dmnsn_map *map, double n, + double *val, void *obj1, void *obj2) +{ + dmnsn_assert(dmnsn_array_size(map->array) > 0, + "Attempt to evaluate empty map."); + + const dmnsn_map_entry *entry = dmnsn_array_first(map->array); + + double n1, n2 = 0.0; + const void *o1, *o2 = entry->object; + + if (n < n2) { + *val = 0.0; + memcpy(obj1, o2, map->obj_size); + memcpy(obj2, o2, map->obj_size); + return; + } + + ptrdiff_t skip = sizeof(dmnsn_map_entry) + map->obj_size; + for (const dmnsn_map_entry *last = dmnsn_array_last(map->array); + entry <= last; + entry = (const dmnsn_map_entry *)((const char *)entry + skip)) { + n1 = n2; + o1 = o2; + + n2 = entry->n; + o2 = entry->object; + + if (n < n2) { + *val = (n - n1)/(n2 - n1); + memcpy(obj1, o1, map->obj_size); + memcpy(obj2, o2, map->obj_size); + return; + } + } + + *val = 1.0; + memcpy(obj1, o2, map->obj_size); + memcpy(obj2, o2, map->obj_size); +} + +void +dmnsn_map_apply(dmnsn_map *map, dmnsn_callback_fn *callback) +{ + for (size_t i = 0; i < dmnsn_array_size(map->array); ++i) { + dmnsn_map_entry *entry = dmnsn_array_at(map->array, i); + callback(entry->object); + } +} -- cgit v1.2.3