Advanced Sprite Rotation

Audio and Graphics
#1

Hello Coronians,

I have a problem and i cant figure out any solution for it.
In my game, enemys are spawned fron random co-ordinates and the hero is at the center… I need to rotate tge randomly spawned enemies towards the player each time its spawned so that it looks towards the player… So how do i do that?

Help is really appreciated
Thank you

#2

A search yielded several results. If you do more thorough search of the Corona forums you’ll find more resources:

https://forums.coronalabs.com/topic/35087-orbiting-object-around-point-using-touch-non-physics/

https://forums.coronalabs.com/topic/21824-rotate-around-point/

https://forums.coronalabs.com/topic/33905-how-do-i-rotate-an-object-around-a-specific-axis/

https://coronalabs.com/blog/coronageek/corona-geek-119/

#3

@Alex i dont need to rotate around…i just need the enemy to face towards the hero each time its spawned at random coordinates and my hero is at the center…

#4

Something like this (example assumes enemy and player are display objects in your game): 

local math2d = require "plugin.math2d" local vec = math2d.diff( enemy, player ) enemy.rotation = math2d.vector2Angle( vec )
#5

@roaminggamer is too quick for me, and already answered, but alternatively:

 enemy.rotation = math.deg(math.atan2(player.y-enemy.y,player.x-enemy.x))

if using images/sprites you’ll need to make sure that they’re aligned to face zero rotation along positive x (otherwise you’ll have to compensate the rotation by whatever built-in non-zero rotation is implied by the image’s facing)

#6

A search yielded several results. If you do more thorough search of the Corona forums you’ll find more resources:

https://forums.coronalabs.com/topic/35087-orbiting-object-around-point-using-touch-non-physics/

https://forums.coronalabs.com/topic/21824-rotate-around-point/

https://forums.coronalabs.com/topic/33905-how-do-i-rotate-an-object-around-a-specific-axis/

https://coronalabs.com/blog/coronageek/corona-geek-119/

#7

@Alex i dont need to rotate around…i just need the enemy to face towards the hero each time its spawned at random coordinates and my hero is at the center…

#8

Something like this (example assumes enemy and player are display objects in your game): 

local math2d = require "plugin.math2d" local vec = math2d.diff( enemy, player ) enemy.rotation = math2d.vector2Angle( vec )
#9

@roaminggamer is too quick for me, and already answered, but alternatively:

 enemy.rotation = math.deg(math.atan2(player.y-enemy.y,player.x-enemy.x))

if using images/sprites you’ll need to make sure that they’re aligned to face zero rotation along positive x (otherwise you’ll have to compensate the rotation by whatever built-in non-zero rotation is implied by the image’s facing)