commit - 1f9aa505738102740c97d05e2445aa89ef4edb27
commit + 925b841e9532a3cc3307cb4e23faf103d2dd2215
blob - c0224f5325b2e6300cf1a7570679ad9f02f69c19
blob + a77e7ee022f268033c146335f21f8534e066da27
--- src/procedures.c
+++ src/procedures.c
continue;
}
- short new_x = mob_data[i].x, new_z = mob_data[i].z;
- uint8_t new_y = mob_data[i].y, yaw = 0;
+ short old_x = mob_data[i].x, old_z = mob_data[i].z;
+ uint8_t old_y = mob_data[i].y;
+ short new_x = old_x, new_z = old_z;
+ uint8_t new_y = old_y, yaw = 0;
+
if (passive) { // Passive mob movement handling
// Move by one block on the X or Z axis
} else { // Hostile mob movement handling
// If we're already next to the player, hurt them and skip movement
- if (closest_dist < 3 && abs(mob_data[i].y - closest_player->y) < 2) {
+ if (closest_dist < 3 && abs(old_y - closest_player->y) < 2) {
hurtEntity(closest_player->client_fd, entity_id, D_generic, 6);
continue;
}
// Move towards the closest player on 8 axis
// The condition nesting ensures a correct yaw at 45 degree turns
- if (closest_player->x < mob_data[i].x) {
+ if (closest_player->x < old_x) {
new_x -= 1; yaw = 64;
- if (closest_player->z < mob_data[i].z) { new_z -= 1; yaw += 32; }
- else if (closest_player->z > mob_data[i].z) { new_z += 1; yaw -= 32; }
+ if (closest_player->z < old_z) { new_z -= 1; yaw += 32; }
+ else if (closest_player->z > old_z) { new_z += 1; yaw -= 32; }
}
- else if (closest_player->x > mob_data[i].x) {
+ else if (closest_player->x > old_x) {
new_x += 1; yaw = 192;
- if (closest_player->z < mob_data[i].z) { new_z -= 1; yaw -= 32; }
- else if (closest_player->z > mob_data[i].z) { new_z += 1; yaw += 32; }
+ if (closest_player->z < old_z) { new_z -= 1; yaw -= 32; }
+ else if (closest_player->z > old_z) { new_z += 1; yaw += 32; }
} else {
- if (closest_player->z < mob_data[i].z) { new_z -= 1; yaw = 128; }
- else if (closest_player->z > mob_data[i].z) { new_z += 1; yaw = 0; }
+ if (closest_player->z < old_z) { new_z -= 1; yaw = 128; }
+ else if (closest_player->z > old_z) { new_z += 1; yaw = 0; }
}
}
- // Vary the yaw angle to look just a little less robotic
- yaw += ((r >> 7) & 31) - 16;
-
- // Check if the blocks we're moving into are passable:
- // if yes, and the block below is solid, keep the same Y level;
- // if yes, but the block below isn't solid, drop down one block;
- // if not, go up by up to one block;
- // if going up isn't possible, skip this iteration.
+ // Holds the block that the mob is moving into
uint8_t block = getBlockAt(new_x, new_y, new_z);
+ // Holds the block above the target block, i.e. the "head" block
uint8_t block_above = getBlockAt(new_x, new_y + 1, new_z);
- if (!isPassableBlock(block) || !isPassableBlock(block_above)) {
- block = block_above;
- block_above = getBlockAt(new_x, new_y + 2, new_z);
- if (isPassableBlock(block) && isPassableBlock(block_above)) new_y += 1;
- else continue;
- } else {
- uint8_t block_below = getBlockAt(new_x, new_y - 1, new_z);
- if (isPassableBlock(block_below) && block != B_water) new_y -= 1;
+
+ if ( // Validate movement on X axis
+ new_x != old_x &&
+ !isPassableBlock(getBlockAt(new_x, new_y + 1, old_z)) ||
+ (
+ !isPassableBlock(getBlockAt(new_x, new_y, old_z)) &&
+ !isPassableBlock(getBlockAt(new_x, new_y + 2, old_z))
+ )
+ ) {
+ new_x = old_x;
+ block = getBlockAt(old_x, new_y, new_z);
+ block_above = getBlockAt(old_x, new_y + 1, new_z);
}
+ if ( // Validate movement on Z axis
+ new_z != old_z &&
+ !isPassableBlock(getBlockAt(old_x, new_y + 1, new_z)) ||
+ (
+ !isPassableBlock(getBlockAt(old_x, new_y, new_z)) &&
+ !isPassableBlock(getBlockAt(old_x, new_y + 2, new_z))
+ )
+ ) {
+ new_z = old_z;
+ block = getBlockAt(new_x, new_y, old_z);
+ block_above = getBlockAt(new_x, new_y + 1, old_z);
+ }
+ if ( // Validate diagonal movement
+ new_x != old_x && new_z != old_z &&
+ !isPassableBlock(block_above) ||
+ (
+ !isPassableBlock(block) &&
+ !isPassableBlock(getBlockAt(new_x, new_y + 2, new_z))
+ )
+ ) {
+ // We know that movement along just one axis is fine thanks to the
+ // checks above, pick one based on proximity.
+ int dist_x = abs(old_x - closest_player->x);
+ int dist_z = abs(old_z - closest_player->z);
+ if (dist_x < dist_z) new_z = old_z;
+ else new_x = old_x;
+ block = getBlockAt(new_x, new_y, new_z);
+ }
+
+ // Check if we're supposed to climb/drop one block
+ // The checks above already ensure that there's enough space to climb
+ if (!isPassableBlock(block)) new_y += 1;
+ else if (isPassableBlock(getBlockAt(new_x, new_y - 1, new_z))) new_y -= 1;
+
+ // Exit early if all movement was cancelled
+ if (new_x == mob_data[i].x && new_z == old_z && new_y == old_y) continue;
+
+ // Prevent collisions with other mobs
+ uint8_t colliding = false;
+ for (int j = 0; j < MAX_MOBS; j ++) {
+ if (j == i) continue;
+ if (mob_data[j].type == 0) continue;
+ if (
+ mob_data[j].x == new_x &&
+ mob_data[j].z == new_z &&
+ abs((int)mob_data[j].y - (int)new_y) < 2
+ ) {
+ colliding = true;
+ break;
+ }
+ }
+ if (colliding) continue;
+
if ( // Hurt mobs that stumble into lava
(block >= B_lava && block < B_lava + 4) ||
(block_above >= B_lava && block_above < B_lava + 4)
mob_data[i].y = new_y;
mob_data[i].z = new_z;
+ // Vary the yaw angle to look just a little less robotic
+ yaw += ((r >> 7) & 31) - 16;
+
// Broadcast relevant entity movement packets
for (int j = 0; j < MAX_PLAYERS; j ++) {
if (player_data[j].client_fd == -1) continue;
