player_api: Prevent knockback when player is set as attached

This is not directly related to player models but fits well
as a convenience feature in player_api.

diff --git a/.luacheckrc b/.luacheckrc
index be8e4bbf051b49b93019a5b10f56f39492c20068..2be56e80e5215073fa652ec2343cd3535ef3b8e6 100644 (file)
--- a/.luacheckrc
+++ b/.luacheckrc
@@ -20,5 +20,8 @@ read_globals = {
 -- Overwrites minetest.handle_node_drops
 files["mods/creative/init.lua"].globals = { "minetest" }
 
+-- Overwrites minetest.calculate_knockback
+files["mods/player_api/api.lua"].globals = { "minetest" }
+
 -- Don't report on legacy definitions of globals.
 files["mods/default/legacy.lua"].global = false

diff --git a/game_api.txt b/game_api.txt
index 52c64f4c1b8762a0b7e12f04d5d9218feba9f3b4..fda371c6fd8fc0690b40dc799918d102d339559b 100644 (file)
--- a/game_api.txt
+++ b/game_api.txt
@@ -424,7 +424,7 @@ Give Initial Stuff API
 Players API
 -----------
 
-The player API can register player models and update the player's appearence
+The player API can register player models and update the player's appearance.
 
 * `player_api.register_model(name, def)`
        * Register a new model to be used by players
@@ -457,6 +457,12 @@ The player API can register player models and update the player's appearence
        * Any of the fields of the returned table may be nil.
        * player: PlayerRef
 
+* `player_api.player_attached`
+       * A table that maps a player name to a boolean.
+       * If the value for a given player is set to true, the default player
+       animations (walking, digging, ...) will no longer be updated.
+       Knockback from damage is also prevented for that player.
+
 ### Model Definition
 
        {
@@ -467,7 +473,7 @@ The player API can register player models and update the player's appearence
                        -- <anim_name> = {x = <start_frame>, y = <end_frame>},
                        foo = {x = 0, y = 19},
                        bar = {x = 20, y = 39},
-               -- ...
+                       -- ...
                },
                collisionbox = {-0.3, 0.0, -0.3, 0.3, 1.7, 0.3}, -- In nodes from feet position
                stepheight = 0.6, -- In nodes

diff --git a/mods/player_api/api.lua b/mods/player_api/api.lua
index 0afd679031501d885a22f5152d19dd74538cb450..4cb3944b71966ea31ed33f415d1b369ea0eea49b 100644 (file)
--- a/mods/player_api/api.lua
+++ b/mods/player_api/api.lua
@@ -96,6 +96,15 @@ end)
 local player_set_animation = player_api.set_animation
 local player_attached = player_api.player_attached
 
+-- Prevent knockback for attached players
+local old_calculate_knockback = minetest.calculate_knockback
+function minetest.calculate_knockback(player, ...)
+       if player_attached[player:get_player_name()] then
+               return 0
+       end
+       return old_calculate_knockback(player, ...)
+end
+
 -- Check each player and apply animations
 minetest.register_globalstep(function(dtime)
        for _, player in pairs(minetest.get_connected_players()) do