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ronny abraham e462e2df4b iadded enemy collisions and modifies

2024-09-11 15:43:09 +03:00

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Lesson 11: Creating the first enemy

Notes
Video Contents

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Notes

Create a New Sprite

add the nodes

Make a new scene
Add a CharacterBody2D node
to the new characterbody node, add a AnimatedSprite2D node

add animations node

add the sprite sheet to the project ./art
go to AnimatedSprite2D node-> Animated Sprite2D -> Animation-> Sprite Frames
1. click where it says empty, and select New Sprite Frames
2. now click inside "New sprite Frames", this will open up the SpriteFrames editor at the bottom
3. The options will be Animations and Animations Frames

add sprite sheet

click on 'default' in the animations section on the left side of the SpriteFrames editor
change name of the animation from 'default' to a name describing the animation
now click on the 'add frames from sprite sheet icon' in the Animations Frame panel of the Sprite Frame Editor
- select the sprites you want to add and hit the Add button
- elements of the add frames
  - horizontal and vertical determines rows and columns in spritesheet
  - size determines pixel sizes
click on the 'new animation' button to add another animation and repeat the process above

Reposition the Sprite

this is important for y-sorting
in the scene, select and move the sprite above the x-axis

see how the animation looks by going to AnimatedSprite2D-> Animation choose from the dropdown in Animation to pick which animation you want incrase or decrease the Frame number for the correct frame

add to world map

save as whatever name you want
switch to world scene
add the sprite into the same layer area as the player

make the sprite movable

add a new script on the root node of the sprite
- erase everything in script except for extends CharacterBody2D at the top

`func _ready`

Vector2(0, 3*16)
- 16 is the height of the sprite
- 3 is how many sprites spaces we move
startPosition: where the sprite starts at
endPosition: about 3 sprite lengths up

`func changeDirection`

switch end and start positions
this way it will regard as what was the end as the new start

`func updateVelocity`

moveDirection: we compare where we have to go 'endPosition' to where we CURRENTLY ARE 'position'
- compare current position to goal position
- get difference
- use the normalization of the difference to find the direction moveDirection.normalized
- use the length of the difference to find if we hit the limit of how far we need to go moveDirection.length < limit
moveDirection.length < limit: if so, change the direction as above
velocity = moveDirection.normalized * speed:
- normalize the moveDirection so we get the direction alone
- multiple it by how far the sprite is expected to move at any given time

full script

extends CharacterBody2D

@export var speed = 20
@export var limit = 0.5

var startPosition
var endPosition

func _ready():
	startPosition = position
	endPosition = startPosition + Vector2(0, 3*16)

func changeDirection():
	var tempEnd = endPosition
	endPosition = startPosition
	startPosition = tempEnd

func updateVelocity():
	var moveDirection = (endPosition - position)

	if moveDirection.length() < limit:
		changeDirection()

	velocity = moveDirection.normalized() * speed

func _physics_process(delta: float) -> void:
	updateVelocity()
	move_and_slide()

update the sprite-moving-script.gd

at beginning of script add: `@onready var animations = $AnimatedSprite2D`

@onready
- The @onready keyword tells Godot to initialize the variable after the node is added to the scene tree. Normally, if you try to access nodes in the scene tree during the script's initialization (before they're fully ready), you might get errors because those nodes don't exist yet.
- With @onready, the variable animations will be initialized once the node and its children have been added to the scene tree, ensuring it's ready to be used when the scene starts running.
var animations
- creates a variable named 'animations'
$AnimatedSprite2D
- The $ symbol is a shortcut in Godot's GDScript to quickly reference child nodes in the scene tree. In this case, $AnimatedSprite2D accesses the AnimatedSprite2D node that is a child of the current node the script is attached to.
- AnimatedSprite2D refers to the specific node in your scene that handles sprite animations. It has functionalities such as starting, stopping, and switching animations.

func updateAnimation

create a variable to hold the name of the animation you decide to play
change this value based on the velocity of the sprite
- e.g. - if the velocity is greater than 0 set the animation to "walkDown"
at the end of the function
- refer to whatever variable is set to your $AnimatedSprite2D objct
- call it's play function and pass the name of the animation you want to play
- e.g. animations_node.play(animation_string_name)
make sure to call this function from the physics process!!!

set end position to world scene marker

add marker 2D node to sprite

go to world scene
right click on sprite
add a Marker2D node
the marker pointer will be right on the sprite if you scroll in
- grab the marker crosshair and move it to where you want

add Marker2D to the sprite script

@export var endPoint: Marker2D
add an export variable
specify the type is Marker2D

assign Marker2D to endpoint

the Sprite inspector will now show an EndPoint property
- select the sprite
go to world, and drag the Marker2D object to the EndPoint property in the inspector for sprite
if you drag over the sprite object, then inspector will open up on that and you can move it over

in func _ready

set endPosition to the global position of the endPoint marker
global position is the actual position in the game
- regular position is relative to teh nodes parents' position
endPosition = endPoint.global_position

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