47 lines
1.3 KiB
Lua
47 lines
1.3 KiB
Lua
-- can be overriden by mods
|
|
function core.calculate_knockback(player, hitter, time_from_last_punch, tool_capabilities, dir, distance, damage)
|
|
if damage == 0 or player:get_armor_groups().immortal then
|
|
return 0.0
|
|
end
|
|
|
|
local m = 8
|
|
-- solve m - m*e^(k*4) = 4 for k
|
|
local k = -0.17328
|
|
local res = m - m * math.exp(k * damage)
|
|
|
|
if distance < 2.0 then
|
|
res = res * 1.1 -- more knockback when closer
|
|
elseif distance > 4.0 then
|
|
res = res * 0.9 -- less when far away
|
|
end
|
|
return res
|
|
end
|
|
|
|
local function vector_absmax(v)
|
|
local max, abs = math.max, math.abs
|
|
return max(max(abs(v.x), abs(v.y)), abs(v.z))
|
|
end
|
|
|
|
core.register_on_punchplayer(function(player, hitter, time_from_last_punch, tool_capabilities, unused_dir, damage)
|
|
if player:get_hp() == 0 then
|
|
return -- RIP
|
|
end
|
|
|
|
-- Server::handleCommand_Interact() adds eye offset to one but not the other
|
|
-- so the direction is slightly off, calculate it ourselves
|
|
local dir = vector.subtract(player:get_pos(), hitter:get_pos())
|
|
local d = vector.length(dir)
|
|
if d ~= 0.0 then
|
|
dir = vector.divide(dir, d)
|
|
end
|
|
|
|
local k = core.calculate_knockback(player, hitter, time_from_last_punch, tool_capabilities, dir, d, damage)
|
|
|
|
local kdir = vector.multiply(dir, k)
|
|
if vector_absmax(kdir) < 1.0 then
|
|
return -- barely noticeable, so don't even send
|
|
end
|
|
|
|
player:add_velocity(kdir)
|
|
end)
|