How To Make A 2D Shooter

What happens when your 2D shooter feels “off” even though the sprite and animation look correct? In most cases, the cause is camera setup, sprite scale/pivot, or input wiring via Unity’s Input System (new input handling).

This section sets up a clean Unity 2D project structure, configures an orthographic camera for pixel-consistent movement, and wires player movement using Unity’s Input System.

OverviewUse this section when starting a new 2D shooter project or when input/camera behavior is inconsistent across machines. It covers: (1) project settings for 2D rendering, (2) camera configuration for orthographic viewing, (3) sprite import/pivot alignment, and (4) Input System code for movement using PlayerInput an InputAction.

Quick ReferenceCamera (2D)Transform.position.z = -10 (typical)

Player movement input: Vector2 move = context.ReadValue<Vector2>();

Unity Input System components:

PlayerInput (behavior: “Send Messages” or “Invoke Unity Events”)

InputActionAsset with an action named Move

Movement API: Rigidbody2D + rb.velocity = new Vector2(x, y) * speed;

Common axis mapping: WASD/Arrow keys -> gamepad left stick -> Vector2

ParametersParameter

Type

Required

Description

move

Vector2

Yes

2D movement vector from the Move action (X=left/right, Y=down/up).

speed

float

Yes

Units per second applied. Example default: 6.0.

useFixedUpdate

bool

No

applying

inputActionName

string

Yes

Name of the action inside. Example: "Move".

deadZone

float

No

Gamepad stick dead zone. Default: 0.125 (if configured in the action).

cameraSize

float

No

Orthographic size. The default depends on your world scale; start with that 5 for many 2D setups.

cameraZ

float

No

Camera Z position. Default: -10 for typical 2D scenes.

Code Exampleusing UnityEngine;

using UnityEngine.InputSystem;

[RequireComponent(typeof(Rigidbody2D))]

public class PlayerMovement2D : MonoBehaviour

{

[Header("Movement")]

[SerializeField] private float speed = 6.0f;

[Header("Input")]

[SerializeField] private string inputActionName = "Move";

private Rigidbody2D rb;

private Vector2 moveInput;

private InputAction moveAction;

private void Awake()

{

rb = GetComponent<Rigidbody2D>();

// Assumes you assigned an InputActionAsset via PlayerInput OR created one in code.

// If using PlayerInput, you can fetch the action from PlayerInput.actions.

var playerInput = GetComponent<PlayerInput>();

if (playerInput == null)

{

Debug.LogError("PlayerMovement2D requires a PlayerInput component on the same GameObject.");

enabled = false;

return;

}

moveAction = playerInput.actions[inputActionName];

if (moveAction == null)

{

Debug.LogError($"InputAction '{inputActionName}' not found in InputActionAsset.");

enabled = false;

return;

}

// Bind callbacks to capture input as it happens.

moveAction.performed += OnMove;

moveAction.canceled += OnMove;

}

private void OnDestroy()

{

moveAction.performed -= OnMove;

moveAction.canceled -= OnMove;

}

private void OnMove(InputAction.CallbackContext context)

{

// ReadValue<Vector2>() expects the action to be configured as a Vector2 control type.

moveInput = context.ReadValue<Vector2>();

}

private void FixedUpdate()

{

// Apply in FixedUpdate for stable physics movement.

Vector2 velocity = moveInput * speed;

rb.velocity = velocity;

}

}Response Format{

"project": {

"renderingMode2D": true,

"camera": {

"projection": "Orthographic",

"orthographic": true,

"transformPositionZ": -10

},

"player": {

"components": ["PlayerInput", "Rigidbody2D", "PlayerMovement2D"]

}

},

"input": {

"inputActionName": "Move",

"expectedValueType": "Vector2",

"bindings": [

{ "source": "Keyboard", "controls": ["W", "A", "S", "D"] },

{ "source": "Gamepad", "controls": ["LeftStick"] }

]

},

"movement": {

"speed": 6.0,

"applicationLoop": "FixedUpdate",

"movementVectorMapping": { "x": "left/right", "y": "down/up" }

}

}Notes & Best PracticesInput system value type must match code: ReadValue<Vector2>() requires the Move action to be configured for Value Type = Vector2; otherwise you’ll read zeroes or get binding warnings.

Physics timing: set velocity FixedUpdate() when using Rigidbody2D to avoid frame-rate-dependent movement.

Camera consistency: keep the camera orthographic and lock its Z position; changing orthographic size alters world-to-screen scale and affects perceived speed.

Sprite pivot/import: ensure sprites have consistent pivot points (often bottom-center for ground movement) and avoid mixed pivots that make

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