Improve CharacterBody script templates.

[yosoyfreeman]

This PR improves the default CharacterBody template for both 2D and 3D. It fixes the following issues:

Input distortion:

The line:

var direction := (transform.basis * Vector3(input_dir.x, 0, input_dir.y)).normalized()

Performs the basis multiplication against a potentially non orthonormal basis. This is often the result of an object which doesn't have an scale of 1. However, because the normalization happens after the possibly wrong basis multiplication, the direction of the original input is now lost. This can be observed if you scale one of the axis to be bigger and move diagonally.

This has been fixed by removing the normalization (Which is not necessary because get_vector always reports at max a unit vector) and using an orthonormal basis instead. The scale no longer alters the input direction. This also allowed to use an smaller deadzone for the joystick, allowing the template to work with controllers too and illustrate how is done.

Acceleration had multiple issues:

It was accelerating instantly, but slowing down is done by moving the speed towards zero in an FPS dependent way, as there is no use of delta involved. Also, accelerating per axis is geometrically incorrect (Same issue as with non normalized vectors) and causes a very unnatural feeling. Also, the fps deceleration was the max speed.

if direction:
		velocity.x = direction.x * SPEED
		velocity.z = direction.z * SPEED
	else:
		velocity.x = move_toward(velocity.x, 0, SPEED)
		velocity.z = move_toward(velocity.z, 0, SPEED)

Now we isolate the horizontal component of our velocity and perform correct acceleration/deceleration

# Move the current horizontal velocity towards the target horizontal velocity by the acceleration factor multiplied by delta.
horizontal_velocity = horizontal_velocity.move_toward(target_horizontal_velocity, ACCEL * delta)

I have also taken into account the up vector of the CharacterBody node. We were ignoring it and assuming always an up vector of 0 1 0. Now everything is done having into account that the up vector is arbitrary.

I have tested it and works nicely. The c# versions are my first attempt with MONO, so i would appreciate some help in those to make sure i followed conventions properly.

[AThousandShips]

See also:

• Improve Godot character controller template #73873

[yosoyfreeman]

Hi! I seen the proposal, but it contains some gameplay specific choices like walk/run, modifying the velocity when changing direction for game feel purposes etc. As it's clear on the discussion, such things can be really specific and are hard to implement in a generic way. This proposal is meant to keep the same functionality we already have, just solving the input, acceleration and up direction issues. I also tried to make more clear how to properly handle acceleration along the horizontal plane and gravity-jump along the up direction.

So this proposal is more about fixing what we have and polishing it than it is about offering more features.

[AThousandShips]

That's a PR with code changes to the same templates so good to get the context from those discussions

[yosoyfreeman]

Thank you a lot for the review! I'll try to have it fixing as soon as possible!

PS: Yes i think the linked PR is relevant! I was just trying to add context to what this one aims for exactly.

Thank you a lot again!

[yosoyfreeman]

I fixed the issues, i think everything is correct now. If that's not the case, tell me and i'll work on it. Thank you!

[Mickeon]

I am not sure if the additional comments help. If anything they make things look more complicated than they are. A lot of this code is good and is readable on its own, it doesn't need the comments repeating themselves.

[Gertkeno]

Really good fixes to the template. I think it's a great starting point now that it's corrected key issues.

Knockback has been challenging for new developers to make with the preivous templates, I see that as a common forum help post; this template very directly fixes those issues, allowing physics driven forces to affect the character bodies.

A lot of developers would slot animations into the if/else direction: and that remains easy to do, though not as obvious. Luckily any old tutorial using the last template should hint at that implementation.

Many do not even notice the old template does not support controllers despite how close it was, just removing .normalized() helps.

I am glad nothing else is added, this template should focus on legiblity and being extensible! I could see myself explaining this to a 10 year old easily, skipping over orthonormalized as rotates the input haha.

[yosoyfreeman]

I just noticed that we are calling jump_velocity to a variable that represents the jump_speed, as speed is just a scalar (what the variable actually is) and velocity implies a vector, which is misleading for the user.

Also, i understand the intention of using constant for the parameters, but things as the speed, the acceleration and the jump speed should be exposed to the editor as i see it. It would also show the user how to export variables.

What do you think? i personally think that exporting them makes more sense, more having into account that constants in gdscript can be changed anyway.

Hearing your thoughts.

Thank you!

[yosoyfreeman]

Ok, i pushed the latest changes and i think everything should be right!

This is the final work involved in this PR:

• Fixed the input distortion issue.

• support for controllers.

• Implemented a correct way to accelerate without square root distortion due each axis using the max acceleration.

• Implemented a variable for acceleration instead of using the max speed.

• Fixed FPS dependency on the acceleration. This is a non trivial issue, but with the current code it's easy to visualize work with. As long as the acceleration is not wrongly manipulated by the user by using some kind of multiplier, we should be OK.

• General refractor of the code.

• Fixes some consistency errors with typed vars.

• Change jump_velocity to jump_speed to reflect that is indeed a scalar, not a vector.

• Exposes speed, accceleration and jump speed to the editor, showing the user how to do it and the correct annotation for both gdscript and c#

I think that's it. I personally like the result a lot and got good feedback, but of course, feel free to tell me if you think it needs further corrections.