map-tile-cache.h

/*
 * SPDX-FileCopyrightText: 2021 Samuel Cuella <samuel.cuella@gmail.com>
 *
 * This file is part of SoFIS - an open source EFIS
 *
 * SPDX-License-Identifier: GPL-2.0-only
 */
#ifndef MAP_TILE_CACHE_H
#define MAP_TILE_CACHE_H
#include <stdio.h>
#include <stdbool.h>

#include "generic-layer.h"
#include "misc.h"

typedef struct{
    Uint32 atime; /*last access time in SDL_Ticks*/

    /* MAP_GAUGE_MAX_LEVEL 23
     * has 8388608 tiles from 0 to 8388607
     * which needs 24 bits. Nearest type is int32
     */
    int32_t x;
    int32_t y;
    uintf8_t level;
    GenericLayer *layer;
}MapTileDescriptor;

typedef struct{
    MapTileDescriptor *tile_cache;
    size_t acache; /*allocated size*/
    size_t ncached; /*currently holding*/
}MapTileCache;

MapTileCache *map_tile_cache_init(MapTileCache *self, size_t cache_size);
MapTileCache *map_tile_cache_dispose(MapTileCache *self);

bool map_tile_cache_set_size(MapTileCache *self, uintf8_t cache_size);
GenericLayer *map_tile_cache_get(MapTileCache *self,
                                 uintf8_t level, int32_t x, int32_t y);
bool map_tile_cache_add(MapTileCache *self, GenericLayer *tile,
                        uintf8_t level, int32_t x, int32_t y);

void map_tile_cache_clear(MapTileCache *self);

static inline bool map_tile_descriptor_match(MapTileDescriptor *self,
                                             uintf8_t level,
                                             int32_t x, int32_t y)
{
    return self->level == level
           && self->x == x
           && self->y == y;
}
#endif /* MAP_TILE_CACHE_H */