// Determines whether this AABB intersects another AABB
bool AABB::intersectsAABB(const AABB& box) const {
const IAPoint &min2 = box.m_min, &max2 = box.m_max;
// Check if x, y, and z planes are inside of the other AABB's x, y, and z planes
return ((X_COORD(m_max) > X_COORD(min2)) && (X_COORD(m_min) < X_COORD(max2)) &&
(Y_COORD(m_max) > Y_COORD(min2)) && (Y_COORD(m_min) < Y_COORD(max2)) &&
(Z_COORD(m_max) > Z_COORD(min2)) && (Z_COORD(m_min) < Z_COORD(max2)));
}
// Find an island entry
struct island_data *closest_island(int x, int y) {
struct island_data *isle, *best = NULL;
int b = USE_SIZE;
for (isle = island_list; isle; isle = isle->next)
if (compute_distance(X_COORD(isle->loc), Y_COORD(isle->loc), x, y) < b) {
best = isle;
b = compute_distance(X_COORD(isle->loc), Y_COORD(isle->loc), x, y);
}
return best;
}
/**
* Convert terrain from one thing to another near other terrain.
*
* @param int from Terrain to convert from.
* @param int to Terrain to convert to.
* @param int near Terrain it must be near.
* @param int dist Distance it must be within.
*/
void replace_near(int from, int to, int near, int dist) {
int x, y, hor, ver, at, loc;
int found;
for (x = 0; x < USE_WIDTH; ++x) {
for (y = 0; y < USE_HEIGHT; ++y) {
at = MAP(x, y);
if (grid[at].type == from) {
found = 0;
for (hor = -dist; hor <= dist && !found; ++hor) {
for (ver = -dist; ver <= dist && !found; ++ver) {
loc = shift(at, hor, ver);
if (loc != -1 && grid[loc].type == near && compute_distance(X_COORD(at), Y_COORD(at), X_COORD(loc), Y_COORD(loc)) <= dist) {
change_grid(at, to);
found = 1;
}
}
}
}
}
}
}
// This takes an initial point 'origin' and translates it by x,y
// may return -1 if no valid location
inline int shift(int origin, int x_shift, int y_shift) {
int loc = origin, y_coord, x_coord;
// sanity
if (loc < 0 || loc >= USE_SIZE) {
return -1;
}
x_coord = X_COORD(loc);
y_coord = Y_COORD(loc);
// handle X
if (x_coord + x_shift < 0) {
if (USE_WRAP_X) {
loc += x_shift + USE_WIDTH;
}
else {
// off the left side
return -1;
}
}
else if (x_coord + x_shift >= USE_WIDTH) {
if (USE_WRAP_X) {
loc += x_shift - USE_WIDTH;
}
else {
// off the right side
return -1;
}
}
else {
loc += x_shift;
}
// handle Y
if (y_coord + y_shift < 0) {
if (USE_WRAP_Y) {
loc += (y_shift * USE_WIDTH) + USE_SIZE;
}
else {
// off the bottom
return -1;
}
}
else if (y_coord + y_shift >= USE_HEIGHT) {
if (USE_WRAP_Y) {
loc += (y_shift * USE_WIDTH) - USE_SIZE;
}
else {
// off the top
return -1;
}
}
else {
loc += (y_shift * USE_WIDTH);
}
// again, we can ONLY return map locations
if (loc >= 0 && loc < USE_SIZE) {
return loc;
}
else {
return -1;
}
}
// Determines whether this AABB contains the given point
bool AABB::contains(const IAPoint &p) const {
// Check if x, y, and z coords are inside of the planes defined by my six x, y, and z sides
return ((X_COORD(m_max) > X_COORD(p)) && (X_COORD(m_min) < X_COORD(p)) &&
(Y_COORD(m_max) > Y_COORD(p)) && (Y_COORD(m_min) < Y_COORD(p)) &&
(Z_COORD(m_max) > Z_COORD(p)) && (Z_COORD(m_min) < Z_COORD(p)));
}
