Lesson Q&A

Use this space for questions related to what you're learning. For any other type of support (website, learning platform, payments, etc...) please get in touch using the contact form.

• A couple minor typosafriendlydogIn the "Can you tell me more about why we shouldn't share common code between the runner and the bouncer?" section: "...even if you have two characters that look the same initially, their code requirements may quickly **derive**, requiring..." -> **diverge** In the final note in the WET glossary entry: "*One big mistake is to consider code as **immuable**.*" -> ***immutable*** 1 0 Mar. 13, 2025
• Error when copying animation scriptChefGorgeousEagle100I copied the code over from my runner script and for some reason I'm getting a new error that wasn't there in the runner script: "Invalid assignment of property or key 'animation_name' with value of type 'int' on a base object of type 'null instance'." ```gdscript class_name Runner extends CharacterBody2D @onready var _runner_visual: RunnerVisual = %RunnerVisualRed @export var acceleration = 1200.0 @export var deceleration = 1080.0 @export var max_speed = 600.0 @onready var _dust: GPUParticles2D = %Dust signal walked_to func _physics_process(delta: float) -> void: var direction := Input.get_vector("move_left", "move_right", "move_up", "move_down") var has_input_direction := direction.length() > 0 if has_input_direction: var desired_velocity = direction * max_speed velocity = velocity.move_toward(desired_velocity, acceleration * delta) _dust.emitting = true else: velocity = velocity.move_toward(Vector2.ZERO, deceleration * delta) _dust.emitting = false move_and_slide() if direction.length() >0.0: _runner_visual.angle = rotate_toward(_runner_visual.angle, direction.orthogonal().angle(), 8.0 * delta) if velocity.length()> max_speed * 0.8: _runner_visual.animation_name = RunnerVisual.Animations.RUN elif velocity.length() > 0.0: _runner_visual.animation_name = RunnerVisual.Animations.WALK else: _runner_visual.animation_name = RunnerVisual.Animations.IDLE ``` And here is my bouncer script: ```gdscript extends CharacterBody2D @export var max_speed = 600.0 @export var acceleration = 1200.0 @export var deceleration = 1080.0 @onready var _runner_visual: RunnerVisual = %RunnerVisualPurple @onready var _dust: GPUParticles2D = %Dust func _physics_process(delta: float) -> void: var direction := Input.get_vector("move_left", "move_right", "move_up", "move_down") var has_input_direction := direction.length() > 0 if has_input_direction: var desired_velocity = direction * max_speed velocity = velocity.move_toward(desired_velocity, acceleration * delta) _dust.emitting = true else: velocity = velocity.move_toward(Vector2.ZERO, deceleration * delta) _dust.emitting = false move_and_slide() if direction.length() >0.0: _runner_visual.angle = rotate_toward(_runner_visual.angle, direction.orthogonal().angle(), 8.0 * delta) if velocity.length()> max_speed * 0.8: _runner_visual.animation_name = RunnerVisual.Animations.RUN elif velocity.length() > 0.0: _runner_visual.animation_name = RunnerVisual.Animations.WALK else: _runner_visual.animation_name = RunnerVisual.Animations.IDLE ``` What am I missing? Thanks! 2 0 Feb. 27, 2025
• Bouncer is still overshooting the mouseGearheadgeekHi, this was such a cool lesson. One small thing is still confusing me though. I understand the logic behind having the desired velocity decrease by a fraction, but Godot seems to disagree. The bouncer doesn't seem to be slowing down fast enough even if I increase the buffer distance to > 200. He continues to overshoot the mouse before coming to a stop. He does eventually stop though. **Am I missing something?** Here's my code--acceleration is 1200.0 and max_speed is 600.0. Edit: I have narrowed down the issue to the velocity assignment: when I set velocity equal to desired_velocity, the speed calculation works as expected, but the bouncer immediately begins moving at max speed. When I use the move_toward function, the bouncer overshoots, but he accelerates smoothly. Edit 2: I increased the division to distance/10000.0 which seems to have worked somewhat, but somehow he still overshoots the mouse. When I increased the distance that he begins slowing down to 150 pixels, he started working as intended, **but why did my numbers have to be so drastically different?** Edit 3: I even tried copying and pasting the code reference in, and our code is essentially identical as this lesson was essentially in the copy phase. Very strange. Edit 4: Increasing the acceleration value to 2000.0 also caused the bouncer to decelerate at an appropriate rate. I was under the impression that the physics_process function worked with a delta value of 1/60, **so shouldn't we have ended up with the same result without changing values?** Edit 5: In the same vein as edit 4, I had to increase the velocity length threshold to 50 pixels in order to get the bouncer's animations to transition in sync with his change in movement speed. ```gdscript func _physics_process(delta: float) -> void: var direction := global_position.direction_to(get_global_mouse_position()) var distance := global_position.distance_to(get_global_mouse_position()) var speed := max_speed if distance > 100 else max_speed * distance / 100 var desired_velocity := direction * speed velocity = velocity.move_toward(desired_velocity, acceleration * delta) move_and_slide() ``` 2 0 Feb. 22, 2025
• I liked that DRY/WET thoughtNoroLately I'm pleased to see that I'm no longuer just a noob in programming, I'm a noob that know how to slowly accomplish things. But like every noob I like to do things like the "grown-up" would do, according to how I imagine they would. I heard about that DRY concept before but never really thought about it. I was thinking it was obviously the way to go. I know I'm chasing it on the personal projects I have, and I stumbled into the same issues you described haha I feel I'll still have to struggle a bit to prevent myself to "optimise" too early, but reading this do help me ease my mind about how a code "should be". It's not about maximum abstraction, something that would work in the most generic way possible, but about clarity and purpose in the very program you building in the moment. No need to face more challenges than the ones you are dealing with right now. 1 0 Nov. 24, 2024
• decelerationram876Hello! I was running through the lessons here quickly and didn't notice that the bouncer was using deceleration somewhere. But he is always present. Is this necessary for future modules or did you just forget to remove it? 2 0 Nov. 06, 2024