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Question My character just falling through the floor

Discussion in 'Editor & General Support' started by fennx1000, Dec 2, 2023.

  1. fennx1000


    Dec 2, 2023
    Please dont say anything about the method i used to move my character around but my character is just falling through the ground
    Code (CSharp):
    1. using System.Collections;
    2. using System.Collections.Generic;
    3. using System.Runtime.CompilerServices;
    4. using UnityEngine;
    6. public class Player : MonoBehaviour
    7. {
    8.     [SerializeField] private float moveSpeed = 7f;
    9.     [SerializeField] private GameInput gameInput;
    11.     private bool isWalking;
    13.     private void Update() {
    14.         HandleMovement();
    15.         HandleInteractions();
    16.     }
    18.     public bool IsWalking() {
    19.         return isWalking;
    20.     }
    22.     private void HandleInteractions() {
    23.         Vector2 inputVector = new Vector2(0, 0);
    24.         Vector3 moveDir = new Vector3(inputVector.x, 0f, inputVector.y);
    25.         float interactDistance = 2f;
    26.         if (Physics.Raycast(transform.position, moveDir, out RaycastHit raycastHit, interactDistance)) {
    27.             Debug.Log(raycastHit.transform);
    28.         } else {
    29.             Debug.Log("-");
    30.         }
    31.     }
    33.     private void HandleMovement() {
    34.         Vector2 inputVector = gameInput.GetMovementVectorNormalized();
    36.         Vector3 moveDir = new Vector3(inputVector.x, 0f, inputVector.y);
    38.         float moveDistance = moveSpeed * Time.deltaTime;
    39.         float playerRadius = .7f;
    40.         float playerHeight = 2f;
    41.         bool canMove = !Physics.CapsuleCast(transform.position, transform.position + Vector3.up * playerHeight, playerRadius, moveDir, moveDistance);
    43.         if (!canMove) {
    44.             // Cannot move towards moveDir
    46.             // Attempt only X movement
    47.             Vector3 moveDirX = new Vector3(moveDir.x, 0, 0).normalized;
    48.             canMove = (moveDir.x < -.5f || moveDir.x > +.5f) && !Physics.CapsuleCast(transform.position, transform.position + Vector3.up * playerHeight, playerRadius, moveDirX, moveDistance);
    50.             if (canMove) {
    51.                 // Can move only on the X
    52.                 moveDir = moveDirX;
    53.             } else {
    54.                 // Cannot move only on the X
    56.                 // Attempt only Z movement
    57.                 Vector3 moveDirZ = new Vector3(0, 0, moveDir.z).normalized;
    58.                 canMove = (moveDir.z < -.5f || moveDir.z > +.5f) && !Physics.CapsuleCast(transform.position, transform.position + Vector3.up * playerHeight, playerRadius, moveDirZ, moveDistance);
    60.                 if (canMove) {
    61.                     // Can move only on the Z
    62.                     moveDir = moveDirZ;
    63.                 } else {
    64.                     // Cannot move in any direction
    65.                 }
    66.             }
    67.         }
    69.         if (canMove) {
    70.             transform.position += moveDir * moveDistance;
    71.         }
    73.         isWalking = moveDir !=;
    75.         float rotateSpeed = 10f;
    76.         transform.forward = Vector3.Slerp(transform.forward, moveDir, Time.deltaTime * rotateSpeed);
    77.     }
    78.     }
  2. Kurt-Dekker


    Mar 16, 2013
    What if the way you are moving your character around IS what is causing you to fall through the floor?

    Or more pointedly, there is NOTHING you are doing above that could ever prevent your character from falling through the ground.

    Well, we won't talk about that. Here are two character controllers that work:

    Ultra simple:

    More full-featured:

    That second one has run, walk, jump, slide, crouch... it's crazy-nutty!!

    Otherwise, here's more reading:

    With Physics (or Physics2D), never manipulate the Transform directly. If you manipulate the Transform directly, you are bypassing the physics system and you can reasonably expect glitching and missed collisions and other physics mayhem.

    This means you may not change transform.position, transform.rotation, you may not call transform.Translate(), transform.Rotate() or other such methods, and also transform.localScale is off limits. You also cannot set rigidbody.position or rigidbody.rotation directly. These ALL bypass physics.

    Always use the .MovePosition() and .MoveRotation() methods on the Rigidbody (or Rigidbody2D) instance in order to move or rotate things. Doing this keeps the physics system informed about what is going on.
  3. fennx1000


    Dec 2, 2023
    A guy on yt used the method i am using and it worked at the start but then i added interactions and it all fell to shreds even though i disabled them so then i tried a few different methods and it did not work
  4. Kurt-Dekker


    Mar 16, 2013
    How to report your problem productively in the Unity3D forums:

    This is the bare minimum of information to report:

    - what you want
    - what you tried
    - what you expected to happen
    - what actually happened, log output, variable values, and especially any errors you see
    - links to actual Unity3D documentation you used to cross-check your work (CRITICAL!!!)

    The purpose of YOU providing links is to make our job easier, while simultaneously showing us that you actually put effort into the process. If you haven't put effort into finding the documentation, why should we bother putting effort into replying?

    If you post a code snippet, ALWAYS USE CODE TAGS:

    How to use code tags:

    - Do not TALK about code without posting it.
    - Do NOT post unformatted code.
    - Do NOT retype code. Use copy/paste properly using code tags.
    - Do NOT post screenshots of code.
    - Do NOT post photographs of code.
    - Do NOT attach entire scripts to your post.
    - ONLY post the relevant code, and then refer to it in your discussion.

    If you haven't got enough information yet about what your program is doing, FIX THAT FIRST.

    Time to start debugging!

    By debugging you can find out exactly what your program is doing so you can fix it.

    Here is how you can begin your exciting new debugging adventures:

    You must find a way to get the information you need in order to reason about what the problem is.

    Once you understand what the problem is, you may begin to reason about a solution to the problem.

    What is often happening in these cases is one of the following:

    - the code you think is executing is not actually executing at all
    - the code is executing far EARLIER or LATER than you think
    - the code is executing far LESS OFTEN than you think
    - the code is executing far MORE OFTEN than you think
    - the code is executing on another GameObject than you think it is
    - you're getting an error or warning and you haven't noticed it in the console window

    To help gain more insight into your problem, I recommend liberally sprinkling
    statements through your code to display information in realtime.

    Doing this should help you answer these types of questions:

    - is this code even running? which parts are running? how often does it run? what order does it run in?
    - what are the names of the GameObjects or Components involved?
    - what are the values of the variables involved? Are they initialized? Are the values reasonable?
    - are you meeting ALL the requirements to receive callbacks such as triggers / colliders (review the documentation)

    Knowing this information will help you reason about the behavior you are seeing.

    You can also supply a second argument to Debug.Log() and when you click the message, it will highlight the object in scene, such as

    If your problem would benefit from in-scene or in-game visualization, Debug.DrawRay() or Debug.DrawLine() can help you visualize things like rays (used in raycasting) or distances.

    You can also call Debug.Break() to pause the Editor when certain interesting pieces of code run, and then study the scene manually, looking for all the parts, where they are, what scripts are on them, etc.

    You can also call GameObject.CreatePrimitive() to emplace debug-marker-ish objects in the scene at runtime.

    You could also just display various important quantities in UI Text elements to watch them change as you play the game.

    Visit Google for how to see console output from builds. If you are running a mobile device you can also view the console output. Google for how on your particular mobile target, such as this answer for iOS: or this answer for Android:

    If you are working in VR, it might be useful to make your on onscreen log output, or integrate one from the asset store, so you can see what is happening as you operate your software.

    Another useful approach is to temporarily strip out everything besides what is necessary to prove your issue. This can simplify and isolate compounding effects of other items in your scene or prefab.

    If your problem is with OnCollision-type functions, print the name of what is passed in!

    Here's an example of putting in a laser-focused Debug.Log() and how that can save you a TON of time wallowing around speculating what might be going wrong:

    If you are looking for how to attach an actual debugger to Unity:

    "When in doubt, print it out!(tm)" - Kurt Dekker (and many others)

    Note: the
    function is an alias for Debug.Log() provided by the MonoBehaviour class.
  5. kdgalla


    Mar 15, 2013
    Code is very context-specific. If you just copy someone else's code it may not work for your own project.
    Kurt-Dekker likes this.