/**
* \brief Returns the ground at the specified point.
*
* Static tiles and dynamic entities are all taken into account here.
*
* \param layer Layer of the point.
* \param x X coordinate of the point.
* \param y Y coordinate of the point.
* \return The ground at this place.
*/
Ground Map::get_ground(Layer layer, int x, int y) const {
if (test_collision_with_border(x, y)) {
// Outside the map bounds.
return Ground::EMPTY;
}
// See if a dynamic entity changes the ground.
// TODO store ground modifiers in a quad tree for performance.
const std::list<Entity*>& ground_modifiers =
entities->get_ground_modifiers(layer);
std::list<Entity*>::const_reverse_iterator it;
const std::list<Entity*>::const_reverse_iterator rend =
ground_modifiers.rend();
for (it = ground_modifiers.rbegin(); it != rend; ++it) {
const Entity& ground_modifier = *(*it);
if (ground_modifier.overlaps(x, y)
&& ground_modifier.get_modified_ground() != Ground::EMPTY
&& ground_modifier.is_enabled()
&& !ground_modifier.is_being_removed()) {
return ground_modifier.get_modified_ground();
}
}
// Otherwise, return the ground defined by static tiles (this is very fast).
return entities->get_tile_ground(layer, x, y);
}
/**
* \brief Returns the ground at the specified point.
*
* Static tiles and dynamic entities are all taken into account here.
*
* \param layer Layer of the point.
* \param x X coordinate of the point.
* \param y Y coordinate of the point.
* \return The ground at this place.
*/
Ground Map::get_ground(int layer, int x, int y) const {
if (test_collision_with_border(x, y)) {
// Outside the map bounds.
return Ground::EMPTY;
}
// See if a dynamic entity changes the ground.
const Rectangle box(Point(x, y), Size(1, 1));
std::vector<EntityPtr> entities_nearby;
get_entities().get_entities_in_rectangle_sorted(box, entities_nearby);
const auto& rend = entities_nearby.rend();
for (auto it = entities_nearby.rbegin(); it != rend; ++it) {
const Entity& entity_nearby = *(*it);
const Ground ground = entity_nearby.get_modified_ground();
if (ground == Ground::EMPTY) {
// The entity has no influence on the ground.
continue;
}
if (entity_nearby.overlaps(x, y) &&
entity_nearby.get_layer() == layer &&
entity_nearby.is_enabled() &&
!entity_nearby.is_being_removed()
) {
return entity_nearby.get_modified_ground();
}
}
// Otherwise, return the ground defined by static tiles (this is very fast).
return entities->get_tile_ground(layer, x, y);
}
/**
* \brief Tests whether a point collides with the ground of the map.
*
* The ground is the terrain of the point. It is defined by the tiles and
* by the presence of entities that may change it
* (like dynamic tiles and destructible items).
*
* This method also returns true if the point is outside the map.
*
* \param layer Layer of the point.
* \param x X of the point in pixels.
* \param y Y of the point in pixels.
* \param entity_to_check The entity to check (used to decide what grounds are
* considered as obstacle).
* \param [out] found_diagonal_wall \c true if the ground under this point was
* a diagonal wall, unchanged otherwise.
* Your algorithm may decide to check more points if there is a diagonal wall.
* \return \c true if this point is on an obstacle.
*/
bool Map::test_collision_with_ground(
Layer layer,
int x,
int y,
const MapEntity& entity_to_check,
bool& found_diagonal_wall) const {
bool on_obstacle = false;
int x_in_tile, y_in_tile;
// If the point is outside the map, this is an obstacle.
if (test_collision_with_border(x, y)) {
return true;
}
// Get the ground property under this point.
Ground ground = get_ground(layer, x, y);
switch (ground) {
case GROUND_EMPTY:
case GROUND_TRAVERSABLE:
case GROUND_GRASS:
case GROUND_ICE:
// The square is not an obstacle.
on_obstacle = false;
break;
case GROUND_WALL:
// The square is entirely an obstacle.
on_obstacle = true;
break;
case GROUND_WALL_TOP_RIGHT:
case GROUND_WALL_TOP_RIGHT_WATER:
// The upper right half of the square is an obstacle
// so we have to test the position of the point in the square.
x_in_tile = x & 7;
y_in_tile = y & 7;
on_obstacle = y_in_tile <= x_in_tile;
found_diagonal_wall = true;
break;
case GROUND_WALL_TOP_LEFT:
case GROUND_WALL_TOP_LEFT_WATER:
// Same thing.
x_in_tile = x & 7;
y_in_tile = y & 7;
on_obstacle = y_in_tile <= 7 - x_in_tile;
found_diagonal_wall = true;
break;
case GROUND_WALL_BOTTOM_LEFT:
case GROUND_WALL_BOTTOM_LEFT_WATER:
x_in_tile = x & 7;
y_in_tile = y & 7;
on_obstacle = y_in_tile >= x_in_tile;
found_diagonal_wall = true;
break;
case GROUND_WALL_BOTTOM_RIGHT:
case GROUND_WALL_BOTTOM_RIGHT_WATER:
x_in_tile = x & 7;
y_in_tile = y & 7;
on_obstacle = y_in_tile >= 7 - x_in_tile;
found_diagonal_wall = true;
break;
case GROUND_LOW_WALL:
on_obstacle = entity_to_check.is_low_wall_obstacle();
break;
case GROUND_SHALLOW_WATER:
on_obstacle = entity_to_check.is_shallow_water_obstacle();
break;
case GROUND_DEEP_WATER:
on_obstacle = entity_to_check.is_deep_water_obstacle();
break;
case GROUND_HOLE:
on_obstacle = entity_to_check.is_hole_obstacle();
break;
case GROUND_LAVA:
on_obstacle = entity_to_check.is_lava_obstacle();
break;
case GROUND_PRICKLE:
on_obstacle = entity_to_check.is_prickle_obstacle();
break;
case GROUND_LADDER:
on_obstacle = entity_to_check.is_ladder_obstacle();
break;
}
return on_obstacle;
}
/**
* \brief Tests whether a point collides with the ground of the map.
*
* The ground is the terrain of the point. It is defined by the tiles and
* by the presence of entities that may change it
* (like dynamic tiles and destructible items).
*
* This method also returns true if the point is outside the map.
*
* \param layer Layer of the point.
* \param x X of the point in pixels.
* \param y Y of the point in pixels.
* \param entity_to_check The entity to check (used to decide what grounds are
* considered as obstacle).
* \param [out] found_diagonal_wall \c true if the ground under this point was
* a diagonal wall, unchanged otherwise.
* Your algorithm may decide to check more points if there is a diagonal wall.
* \return \c true if this point is on an obstacle.
*/
bool Map::test_collision_with_ground(
int layer,
int x,
int y,
const Entity& entity_to_check,
bool& found_diagonal_wall) const {
bool on_obstacle = false;
int x_in_tile, y_in_tile;
// If the point is outside the map, this is an obstacle.
if (test_collision_with_border(x, y)) {
return true;
}
// Get the ground property under this point.
Ground ground = get_ground(layer, x, y);
switch (ground) {
case Ground::EMPTY:
case Ground::TRAVERSABLE:
case Ground::GRASS:
case Ground::ICE:
// The square is not an obstacle.
on_obstacle = false;
break;
case Ground::WALL:
// The square is entirely an obstacle.
on_obstacle = true;
break;
case Ground::WALL_TOP_RIGHT:
case Ground::WALL_TOP_RIGHT_WATER:
// The upper right half of the square is an obstacle
// so we have to test the position of the point in the square.
x_in_tile = x & 7;
y_in_tile = y & 7;
on_obstacle = y_in_tile <= x_in_tile;
found_diagonal_wall = true;
break;
case Ground::WALL_TOP_LEFT:
case Ground::WALL_TOP_LEFT_WATER:
// Same thing.
x_in_tile = x & 7;
y_in_tile = y & 7;
on_obstacle = y_in_tile <= 7 - x_in_tile;
found_diagonal_wall = true;
break;
case Ground::WALL_BOTTOM_LEFT:
case Ground::WALL_BOTTOM_LEFT_WATER:
x_in_tile = x & 7;
y_in_tile = y & 7;
on_obstacle = y_in_tile >= x_in_tile;
found_diagonal_wall = true;
break;
case Ground::WALL_BOTTOM_RIGHT:
case Ground::WALL_BOTTOM_RIGHT_WATER:
x_in_tile = x & 7;
y_in_tile = y & 7;
on_obstacle = y_in_tile >= 7 - x_in_tile;
found_diagonal_wall = true;
break;
case Ground::LOW_WALL:
case Ground::SHALLOW_WATER:
case Ground::DEEP_WATER:
case Ground::HOLE:
case Ground::LAVA:
case Ground::PRICKLE:
case Ground::LADDER:
on_obstacle = entity_to_check.is_ground_obstacle(ground);
break;
}
return on_obstacle;
}
