Collision detection support

Questions
#1

I am currently making a game on Defold and this was where I was pushed by the website to find technical support. I am trying to get collision messages from an enemy game object in my game – I have already got it working for my player game object so I thought it would be easy – but am having some problems. This is the code for the enemy I want to get collision messages:

function init(self)
	self.speed=250
	self.direction = 1
	
	new_enemy1(self)
end

function new_enemy1(self)
	-- spawn enemy1
	self.enemy1_table = {}
	local position
	local enemy_id

	-- set position of enemy on screen
	for y = 500,290,-70 do
		for x = 100,550,75 do
			pos = vmath.vector3(700,600,0)
			enemy_id = factory.create("#enemy1_factory", pos)

			-- hold reference to enemy
			table.insert(self.enemy1_table, enemy_id)
		end
	end
end

function update(self, dt)
	local movement = vmath.vector3(self.direction * self.speed * dt, 0, 0)

	-- Update the position of each enemy in the enemy1_table
	for _, enemy_id in ipairs(self.enemy1_table) do
		local enemy_pos = go.get_position(enemy_id)
		go.set_position(enemy_pos + movement, enemy_id)
	end
end

function on_message(self, message_id, message, sender)
	print("Received message:", message_id)
	-- Handle collision
	if message_id == hash("contact_point_response") then
		print("Collision Message:")
		print("  Normal:", message.normal)
		print("  Distance:", message.distance)
		print("  Other:", message.other)
		local newpos = go.get_position() + message.normal * message.distance
		go.set_position(newpos)
	end
end

I attached a picture of where the code is placed in main.collection. I made the enemy1 game object in the main folder in the assets panel which I also have a screenshot of. I have the mask and Group set up for both the enemy and the boundary I want to receive a collision message at. I will link a screenshot of both. The enemy is spawned with a factory and I have it moving to the right and it just moves past the boundary and nothing is written in the console. I will add a screenshot of what I see on the console.

https://imgpile.com/i/CXTpZl - console
https://imgpile.com/i/CXT3n8 - boundary collision object
https://imgpile.com/i/CXTgkS - enemy collision object
https://imgpile.com/i/CXT6xb - Assets panel
https://imgpile.com/i/CXTEo3 - main.collection outline panel

#2

Welcome to Defold. Have you added the enemy collision object to the enemy game object?

2 Likes
#3

Collision messages don’t get sent back to the factory that the object was spawned from. You’ll need a script attached to the enemy object to receive the messages.

You can drag and drop images into your forum post by the way!

2 Likes
#4

Thanks a lot!!! I will fix that now.
I’ll do that next time hahah