Hi, I am making a platformer, and I have modelled my player with dynamic physics, as they will be interacting with blocks, pushing them etc. The movement works fine, but I am having trouble getting the jumping to work correctly?
Currently, when I press the jump key, the player performs a jump, but the magnitude is so small, even though the force is great. I have tried increasing the force, and reducing the mass of the player, but the issue still remains.
Any help would be greatly appreciated 
local right = hash("right") -- using a hash of the action_ids saves time
local left = hash("left") -- prehashing also saves resources, as it does not have to be hashed each time input detected
local jump = hash("jump")
local idle = hash("idle") -- prehashing of animation names, saves resources
local walk = hash("walk")
local current_anim = idle -- set to idle by default, as this is the starting animation
local r_colliding = false -- sets flags to false at start of level
local l_colliding = false -- sets flags to false at start of level
local on_ground = false -- is player currently on the ground
local jump_force = vmath.vector3(0,5000,0)
local x_movement = 200 -- not hardcoded, so can be changed if need be
local move_direction = 0
function init(self)
msg.post(".", "acquire_input_focus") -- allows the script to handle inputs
end
local function animate(anim) -- dedicated for animations, improves modularity
if current_anim ~= anim then -- checks that the animation is not already being played
sprite.play_flipbook("#sprite", anim)
current_anim = anim -- updates the current animation
end
if move_direction == 1 then -- if facing right
sprite.set_hflip("#sprite",false) -- flip -> false
elseif move_direction == -1 then -- if facing left
sprite.set_hflip("#sprite",true) -- flip -> true
end
end
local function update_collision_state(message)
if message.normal.x > 0.7 then -- if collision on left
r_colliding = false
l_colliding = true
elseif message.normal.x < -0.7 then -- if collision on right
r_colliding = true
l_colliding = false
end
if message.normal.y > 0.7 then -- if colliding with the ground
on_ground = true
end
end
function on_message(self, message_id, message, sender) -- when the object recieves a message
if message_id == hash("contact_point_response") then -- if collision, call function
update_collision_state(message)
end
end
function fixed_update(self, dt)
local pos = go.get_position() -- Gets the current position
pos.x = pos.x + x_movement * move_direction * dt -- x_position + x_movement, * dir & diff between prev frame to ensure movement not dependent on fps
go.set_position(pos) -- updates pos
if move_direction == 1 and l_colliding then -- code to reset the values of l_colliding and r_colliding, so if moving right l_colliding to false
l_colliding = false
elseif move_direction == -1 and r_colliding then
r_colliding = false
end
if (move_direction == 1 and not r_colliding) or (move_direction == -1 and not l_colliding) then -- code to play correct animation, if player walking and not colliding in same direction
animate(walk)
else
animate(idle)
end
end
function on_input(self, action_id, action)
-- If the key is released, stop movement
if action.released then
if action_id == right and move_direction == 1 then
move_direction = 0 -- Stop moving right when right is released
elseif action_id == left and move_direction == -1 then
move_direction = 0 -- Stop moving left when left is released
end
else
-- Handle right input
if action_id == right and move_direction == 0 then
move_direction = 1 -- Move right if no direction is currently active
-- Handle left input
elseif action_id == left and move_direction == 0 then
move_direction = -1 -- Move left if no direction is currently active
end
end
if action_id == jump and on_ground then -- if jump action, and player on ground then jump is true
msg.post("#collisionobject", "apply_force",{
force = jump_force,
position = go.get_world_position()
})
on_ground = false -- player no longer on the ground
end
end