getting_started/first_3d_game/03.player_movement_code

[giscus[bot]]

getting_started/first_3d_game/03.player_movement_code

It's time to code! We're going to use the input actions we created in the last part to move the character. Right-click the Player node and select Attach Script to add a new script to it. In the pop...

https://docs.godotengine.org/en/stable/getting_started/first_3d_game/03.player_movement_code.html

[orchard800]

Shouldn't the CameraPivot be attached to the player somehow?

[Calinou]

In this demo, the camera has a fixed position and covers the entire level (similar to minigames like Mario Party). Therefore, it doesn't need to follow the player.

[Elliott-Tanner]

When I follow these instructions, I end up with the camera looking directly down, with no angle. How should I fix this?

[discotwig]

"Select the CameraPivot and rotate it -45 degrees around the X axis (using the red circle). You'll see the camera move as if it was attached to a crane."
You can press E to enter Rotate Mode and use the red arc to rotate downward.

[Lensco825]

Had the same problem. I set the camera node's y-axis position to 18m, then you set it's projection to "Orthogonal" with it's size set to 19m.

[Deadly-Cicada]

This happened to me as well. I found that I was rotating the "Camera" and not the "CameraPivot".

When we moved the "Camera" back 19 units we should have left the "CameraPivot" in the center of the floor where the character was at. If we then move the red arc on "CameraPivot" our "Camera" will use the origin point of the pivot to move as opposed to its new location at -19Y.

[Wadahell]

My character doesn't move, it only turns to the side of the respective input
Tried moving the floor, the char, the collision sphere, didn't work

Possible relevant info: Camera dimentions are a little different from the article..

[Wadahell]

Yes, like 3 times, at this point i'm believing starting again from scratch is the best option
Did your's eventually worked?

[mtt-sp]

yeah

[Wadahell]

Found it! it was some indentation on the code, i gave up finding it and used the code at the end of the page
Also, theres no code for jump

func _physics_process(delta):
...
if Input.is_action_pressed("jump"):
direction.y += 1

used this and only partially worked (it did something

[kynoch]

This happened to me too. I diffed my code with the example and it matched exactly, but after printing the target velocity I noticed the y value was increasing steadily.

I think what happened was the player model was inside the floor. Raising it on the y axis in the 3D mode fixed it at any rate.

[GlitchyPixel]

Yeah I faced it too, found it was just a problem in the placement on the "Player" object. Increase it's y transform to be above the ground when starting the game and it get's fixed. The problem was because the Player object was actually kind of being "embedded" onto the ground.

[BryceDMonaco]

Here, we're going to make all calculations using the _physics_process() virtual function. Like _process(), it allows you to update the node every frame

Isn't this incorrect? My understanding is _physics_process() runs at a fixed rate independent of visual frame rate. Maybe explaining fixed rate updates and physics frames is out of the scope of this tutorial, but I think it can lead to confusion to those who are completely new to game dev.

[bruno-normande]

# The downward acceleration when in the air, in meters per second squared.
@export var fall_acceleration = 75

75 is much greater than earth's gravity (~9.8m/s2). Is that so that the player falls faster? Or is there some mechanical reason for that? (or is the comment wrong?)

[ostap-tymchenko]

Video games in general and historically, not just in Godot, have very high gravity. You can see this in every game from original super mario (~22.1) or minecraft (~32.7). 75 is rather high but there is also no acceleration here so that's something to consider, as well as what jumping actually does in the game, that is killing creeps, and for that it needs to be very high and responsive in order to land quickly after jumping.

[vmorris]

There's no instruction to raise the Y position of the camera.

[ragn4rok234]

Moving the Y position of the camera isn't required. Changing the X rotation on the CameraPivot node to -45 raises the camera to the correct position

[vmorris]

This was not my experience. The camera node is at 0,0,0, rotating it -45 X doesn't raise it up at all.

[ragn4rok234]

You're not supposed to rotate the camera node itself, you need to rotate the CameraPivot Node that the camera is a child of.
Also the camera node itself should be at around (0,0,19) not (0,0,0) based on the instructions in the lesson.

[vmorris]

Yes, you're right about the position around (0,0.19). I will try again with the CameraPivot Node instead. Thanks!

[guiYudi]

I had to move it up a bit. My CameraPivot (marker3D) is at (0,15,19) rotated to (-45º, 0, 0) and my Camera3D is at (0,0,0) (with no rotation). If I position the CameraPivot (marker3D) at (0,0,19) it only renders the top half of the viewport, and when the player moves down, it clips into an invisible area (probably clipping into the camera).

[guiYudi]

if not is_on_floor(): # If in the air, fall towards the floor. Literally gravity
    target_velocity.y = target_velocity.y - (fall_acceleration * delta)

Why not just target_velocity.y -= (fall_acceleration * delta) ?

[Headedbranch225]

write a pull request if the code works and you think it is better coding practice

[BluesAdam]

@Headedbranch225 we are all here to inquire and learn. The worst thing you can do is sass someone for being curious and asking a question. Please consider responding to questions in a more constructive and encouraging manner.

I wonder the answer to this question as well. So if anyone could please chime in.

[ImminentTofu]

I think it's because if you miss the "if not is_on_floor():" your character constantly builds up speed downward and never resets. So when you go to jump it'll probably keep you glued to the ground depending on how you code it. Also might just be a best practice thing; if there's a cliff and you walk off it, you'll be smacked into the ground at mach 5 instead of at the fall_acceleration.

[pikaphew9000]

My forward backword movement is inverted

[pikaphew9000]

I checked out the camera and code everything was right

[guiYudi]

Did you map the keys correctly in the Input Mapping? move_forward should be mapped to up and move_back to down keys.

[BluesAdam]

In Godot, forward is -1 and backwards is 1 when it comes to y-axis. You might want to double check. That caught me by surprise as well.

[BluesAdam]

Sorry, meant to say z-axis.

[BrunoProsdocimo]

My code doesn't do anything. I'm trying to code with C# using Visual Studio Code and the code seems to be connected to the project correctly as when I click the "script" icon on the Player scene it opens VS Code with the all the code in it. When I play the game however the code seems like it doesn't do anything. I've tried debugging it by printing lines in output when the buttons in the input are pressed but that also doesn't happen. I've also added the proper inputs in the editor. I've also tried just copying the entire code from this page into VS Code and that didn't work.

At this point I'm assuming it's something with the editor, and I've even downloaded the Godot Engine .NET from their website, reloaded the project and it also didn't work. I don't know what's going on, can anybody give me a hand?

[Menekrr]

Hey!

If I'm understanding you correctly, you were saying that when you ran the game (after choosing to run the Main scene), you can't move the character, and any print() statements you put into the _physics_process() function also don't print anything.

If that's the case, I encountered the exact same issue, but not sure if the circumstances were the same as yours.

When I instantiated a Player scene into the Main scene, I accidentally chose the art/player.glb instead of the player.tscn. I noticed something was weird when I saw that my Player scene was capitalized (capital 'P'), but the instantiated player in Main was not capitalized (lower-case 'p').

When I deleted the "player" instance and instead instantiated a "Player", my problems went away.

Hope that might help you! Could you try it out?

[SarahRamage]

Thank you so much that's exactly what I did also

[rdepew]

@Menekrr, this error bit me also: I chose the player.glb file instead of the player.tscn file. Deleting the small-p instance and instantiating a new Player using the player.tscn file fixed it for me.

[Nedus]

@Menekrr exactly my problem too! Weird that by wrongly instantiating the script it would also visualize the mesh, this was what threw me off.

[GistOfSpirit]

The CharacterBody3D.is_on_floor() function returns true if the body collided with the floor in this frame. That's why we apply gravity to the Player only while it is in the air.

What counts as "floor" though? I think it would be useful to have a short explanation of that.

As far as I can tell, the big rectangle we created doesn't have any special properties that would label it as "floor" (as opposed to "wall", "character" etc.). I presume that any collision shape is a floor as far as is_on_floor is concerned?

[Calinou]

I presume that any collision shape is a floor as far as is_on_floor is concerned?

Whether the CharacterBody is considered to be "on floor" is determined by the collision normal, not the collision shape type or its metadata.

The maximum collision normal value that is considered "on floor" can be configured by adjusting Floor > Max Angle in the inspector. This is the steepest angle that characters will be able to walk on without being considered airborne (and therefore sliding off the ramp).

[RobbiewOnline]

I have this mostly working, the player is visible on the floor, stationery. When I click any of the movement keys the character moves in that direction, then falls through the floor.

I thought it must be the CollisionShape3D node being lower than the player, so I moved it up. It made no difference, so I moved the floor even further down.

When I launch the game I now see the player fall and stop at the floor. But when I press a key to move, the player still falls through the ground again.

‼️FYI ‼️

A number of times I went to run the game and I'd see a grey window, not my game .. took me a while to notice that it was when I was tinkering with the Player, because the 'main' scene tab isn't selected (player tab was), so the scene being 'run' was not the 'main' but the 'player' scene which has no camera🤦‍♂️

[RobbiewOnline]

And to be clear I did copy + paste the code above, which has the block

	if not is_on_floor():
		target_velocity.y = target_velocity.y - (fall_acceleration * delta)

	velocity = target_velocity
	move_and_slide()

[RobbiewOnline]

Okay, clear head and found my issue - I'd set the size of my MeshInstance3D correctly, but missed the steps to set my CollisionShape3D, which now makes sense...

When the game first started the character would fall precisely onto the default CollisionShape3D, as soon as I moved the character would fall off the CollisionShape3D area.

For others, this is the step I missed for CollisionShape3D...

A box's wireframe appears in the viewport with three orange dots. You can click and drag these to edit the shape's extents interactively. We can also precisely set the size in the inspector. Click on the BoxShape3D to expand the resource. Set its Size to 60 on the X-axis, 2 for the Y-axis, and 60 for the Z-axis.

[Userunmanned]

The movement works just fine with GDScript, but it doesn't work with C#. I am using the exact code provided.

[Userunmanned]

I have .NET 9.0 on my computer if that is needed

[Calinou]

Please ask support questions on other community channels: https://godotengine.org/community/

[Userunmanned]

But, shouldn't it work nonetheless?

[balloonbrain]

why use .ZERO instead of initialising the Vector3D like: "Vector3D(0.0, 0.0, 0.0)" is there a reason or is it just clarity and ease of use?

[Calinou]

It's just for clarity. You can also use Vector3() which is the same as Vector3.ZERO.

[balloonbrain]

thanks!

[sryimnew2this]

These are hilariously easy to follow; thanks, I love it!
One question, though, please?
How do I do this with C++ using gd extensions? I've been shamelessly struggling for hours trying to figure it out

(I have a bouncy sprite moving across the screen in 2d thanks to bouncysprite.gdextension, & I tried to modify it to make a movecharacter.gdextension for 3d using vector3 & character_body3d, but i'm honestly lost)

I am grateful for any and all assistance! Thanks

[sryimnew2this]

I'm using visual studio 2019 if it helps, at all

[Userunmanned]

I literally directly followed the tutorial and copy and pasted the C# code and it still didn't work.

Your mocking is kind of funny though, I have to admit.

[sryimnew2this]

no no, I was being genuine; I was worried before I started that it would be difficult to follow (I tried doing the GDExtensions last year and somewhat struggled) but this in comparison is 100x easier and quite enjoyable!

Would be great if the c++ gdextension was a bit easier to use, though. (Although I am a fresh novice)

[playhorsejr]

Im getting an error code
player.gd:25 @ _physics_process(): Node not found: "Pivot" (relative to "/root/main/player").
what can i do to fix this, using gdscript and copy pasted the code into my script and still didnt work

[ryanttb]

1. Did you include the dollar sign? $Pivot.basis
2. Is the Pivot node directly under your Player node?

Please post your script.

[playhorsejr]

extends CharacterBody3D

# How fast the player moves in meters per second.
@export var speed = 14
# The downward acceleration when in the air, in meters per second squared.
@export var fall_acceleration = 75

var target_velocity = Vector3()


func _physics_process(delta):
	var direction = Vector3()

	if Input.is_action_pressed("move right"):
		direction.x += 1
	if Input.is_action_pressed("move left"):
		direction.x -= 1
	if Input.is_action_pressed("move back"):
		direction.z += 1
	if Input.is_action_pressed("move forward"):
		direction.z -= 1

	if direction != Vector3():
		direction = direction.normalized()
		$Pivot.basis = Basis.looking_at(direction)

	# Ground Velocity
	target_velocity.x = direction.x * speed
	target_velocity.z = direction.z * speed

	# Vertical Velocity
	if not is_on_floor(): # If in the air, fall towards the floor. Literally gravity
		target_velocity.y = target_velocity.y - (fall_acceleration * delta)

	# Moving the Character
	velocity = target_velocity
	move_and_slide()

[ryanttb]

One comment, in the Previous lesson, I moved my Player's CollisionShape3D Position up too high, to y = 1m. It kept falling halfway through the floor. I changed it to 0.5m and it's fine now.

[n-hdev]

Yes, I had this too, so I went back to look at the collision shape and I think I'd been using the axis markers rather than the shape outline to position the shape in the earlier tutorial.

On the other hand, half through the floor means you just see its eye, very creepy, much scarier... almost got a newspaper out to squish it dead on the screen.

[molorosh]

So the player didn't move for me at first. But then I noticed that in the Node tree view my player was not showing a script / document icon - and then I realised - I had added the player.glb model file instead of the scene file. I removed the node and added the child scene instance of scene.tscn and then it all worked great.

I hope that helps other people. :-)

[slegetank]

This is really helpful! Thank you for saving me time!

[SaleemVFX]

!!!!! THISSSS I've been frustrated why it wasn't working lol . Thanks much

[burckd]

I could not found any CameraPivot node to add while using Godot Engine v4.4
Instead I added a Node3d and named it Pivot, so far everything works fine

I might be missing something, but I hope this helps.

[Calinou]

There is no CameraPivot node in Godot. This page tells you to create a Marker3D node and rename it CameraPivot instead:

Create a new Marker3D, and name it CameraPivot. Select CameraPivot and add a child node Camera3D to it.

[burckd]

Thanks for your time, sorry. I totally missed something. Should I just delete the comment?

[Calinou]

Should I just delete the comment?

You can leave it here if you want, or remove it depending on what you're most comfortable with.

[gunererd]

Is there a particular reason or advantage to put Camera3D under a pivot node? Why don't we position and rotate camera directly?

[KonscienceGit]

The Pivot node allow to rotate the translated Camera, in a way that the camera always look at the Pivot position no mater the rotation.
In this example, the Camera node is moved backward by 19 meters, so when we later apply the -45° rotation to the parent Pivot node, the Camera doesn't just rotate on itself, but instead rotate around it's origin (which is 19 meters in front of it).

In short, applying the rotation on the pivot allow to handle the camera like if it was on a selfie stick.

[TheDeadMeasure]

When I try to pull the Camera3D on the z axis (with it selected in the Scene panel), the view shown by the camera barely leaves the character's shape. How do I fix that? (To get the effect similar to that shown in the tutorial pics, I have to pull the camera about 850 units away.)

[KonscienceGit]

It seems your Camera FOV (field of view) setting in the right panel (inspector) was changed to 1°, which is probably why it feels like overly zoomed onto the character. You can press the circling arrow symbol to revert it to the default value (75°).

[TheDeadMeasure]

Thank you much!

[Gardioz]

Hi!

I've been stuck at running the scene but only getting a grey background. Think it's about something regarding directional light or the player.glb file. Tried many configs in both but can't get it working properly, can anybody help?

[Calinou]

You can move around in the running project by clicking the 3D button at the top of the game window, then clicking the camera icon in the toolbar on the right (still on the game window). After doing that, you can hold the right mouse button and use WASD to move around while the game is running. This is useful to diagnose issues like that, so you can see what went wrong exactly.

[KermitThePog]

Is there a reason to multiply fall acceleration by delta when using _physics_process(), given that uses fixed time intervals?