55 lines
2.3 KiB
C
55 lines
2.3 KiB
C
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//---
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// pathfinding: Methods to find short enough paths to move around the map
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//---
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#pragma once
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#include "map.h"
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#include "geometry.h"
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/* Returns a BFS from start to end, with grid-based points. */
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ipoint_t *bfs(map_t const *map, ipoint_t start, ipoint_t end, int *count);
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/* raycast_clear(): Check collisions with the map for a straight ray
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This function checks if the straight-line path from [start] to [end] is
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clear of collisions with walls. It checks all tile transitions to ensure
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that no solid tile is crossed. This function checks movement only for a ray
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of no width, which is suitable for objects tht do not collide with walls.
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TODO: Use tile hitboxes rather than simply checking if the tile is solid.
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When hitting diagonal corners perfectly, this functions moves up/down before
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moving left/right and ignores the other possibility.
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Returns [true] if the path is clear, [false] otherwise. */
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bool raycast_clear(map_t const *map, fpoint_t start, fpoint_t end);
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/* raycast_clear_hitbox(): Check collisions with the map for a hitbox
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This function is similar to raycast_clear(), but it accounts for the width
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of the hitbox being moved. The hitbox should be centered around (0,0) so
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that the path brings that center from [start] to [end].
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This function simply checks raycast_clear() for two separate rays at the
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opposite corners of the hitbox, perpendicular to the direction of the
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movement. In addition, collisions at the start and end point are tested.
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TODO: Currently, raycast_clear_hitbox() does not work if the hitbox if
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larger than the obstacles to avoid (as it casts rays only at the
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corners of the hitbox, not in the middle).
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Returns [true] if the path is clear, [false] otherwise. */
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bool raycast_clear_hitbox(map_t const *map, fpoint_t start, fpoint_t end,
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frect_t hitbox);
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/* Returns a full continuous path from start to end. */
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fpoint_t *pathfind(map_t const *map, fpoint_t start, fpoint_t end, int *count,
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ipoint_t **p_grid, int *p_grid_length, frect_t hitbox);
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/* Returns the first point to treach to move from start to end. Note that the
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direction can be reevaluated at each frame, giving a smooth path. This is
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faster than pathfind(). Returns [start] if pathfinding fails. */
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fpoint_t pathfind_one(map_t const *map, fpoint_t start, fpoint_t end,
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frect_t hitbox);
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