Video Game Engine Gravity - c#

I was trying to make a game engine that used gravity. I tried making it so your character moves down one pixel (Up in a Winforms)every time a timer goes off, and if it's touching the ground, it goes up until it stop touching it. However, it makes your character bounce up and down continually. Is there any other way I could go about this?

Check if subtracting 1 pixel would put you below ground FIRST, and don't subtract if so.

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Character stuck on a tile unity3d

I have no idea what to say, but I have this image which shows how the character is stuck, the character gets stuck when I try to jump couple times, character is not falling.
if I jump 1 more time, the character jumps and drops to the ground
Here is movement code (didn't want to paste it here cuz it is kind of big)
oh and btw this is 2.5d game, 2d in a 3d engine
Maybe you are stuck on a subpixel?
Check the colliders: Window->Analysis->Physics Debugger.
Check the x-coordinates of the blocks in each "tower".
Change from boxcollider to spherecollider (so you slip off of small edges?)
What about the "GroundCheck Transform"? I don't see why it's a separate transform, is it a child of the player?

Hitting a character physics?

Ok, for this task I need to coordinate physics hitting a game object at a certain point and animation, to create the illusion of punching a character and he stumbles back as if propelled by that contact point.
I have rigid bodies on both the hitting object and character being hit, and can tell when the hitting object enters the character's box collider. What I thought to do first was create an impulse at the contact point then trigger my pre made character animation -
Vector3 direction = (this.transform.position - collider.transform.position) / (this.transform.position - collider.transform.position).magnitude;
this.transform.GetComponent<Rigidbody>().AddForce(direction, ForceMode.Impulse);
Problem is this just makes the character float slowly off opposite the hitting object (Rigidbody has gravity checked on character), and depending on where the character is facing, the animation looks not coordinated with the punch.
I wanted to see whether there's a streamlined way of doing this - how can I create a realistic punch/moving backward situation in Unity?
There's no easy way to get this behavior out-of-the-box with Unity. You will need to script a blending of ragdoll physics with animations.
One approach you might want to try is a system that "pins" your ragdoll to the bones of an animation, and if a collision occurs, the ragdoll unpins itself (partially or completely) from the bones, temporarily. When/if it completes being affected by physics, you would probably want to animate from a keyframe dynamically created based on the position of the ragdoll to a target keyframe.
There are also tools like PuppetMaster on the asset store that are meant to do things like this, but they are often not free, because they are difficult to make well.

Fast swipe movement of GameObject does not collide with Colliders

I am working on a Unity game in a 2D environment. The player GameObject has a Rigidbody2D attached. It moves horizontally when swiping. When swipe is too fast, it does not collide with the Colliders. Maybe it changes its transform position before detecting collision? It does not happen when the swipe is slow.
Based upon your problem I am assuming you are moving your object in the Update() function (please correct me if not). This means you are moving the object a certain amount every frame. However, Unity checks colliders and does physics calculations on a different time interval (Fixed Timestep, https://docs.unity3d.com/Manual/class-TimeManager.html).
Just before the objects collide, the colliders are checked. Unity calculates colliders every Fixed Timestep (default 0.02 times a second). If unity does not detect a collision it means your objects intersect for less time than the Fixed Timestep, or in other words, they are moving very fast (like you describe your situation). One (bad) way to fix this would be to decrease the amount of time in between physics calculations. However, this would greatly decrease your programs efficiency.
Instead, consider moving your object in the function FixedUpdate() so that the object only moves every time the physics checks for a collision. This should fix your problem.
Take a look at the 3rd answer (by Garth-Smith):
https://forum.unity3d.com/threads/rigidbody-2d-wont-collide-with-another-object-when-its-moving-really-fast.248786/
I particularly want to highlight the part:
If you have a Rigidbody2D, you should be moving it in FixedUpdate()
using rigidbody2D.MovePosition(Vector2). This will move the
Rigidbody2D through space, instead of teleporting it from point A to
point B.
The second part about Raycasts should not be necessary for your problem, but if you continue to experience problems your can use them to check a range as jdweng stated in his comment.
Here are a couple places to learn about Raycasts if you are unfamiliar with them:
https://docs.unity3d.com/ScriptReference/Physics2D.Raycast.html
https://unity3d.com/learn/tutorials/topics/physics/raycasting
If the movement of your object is too fast it will simply ignore the collision since it never touches the actual collider - it just skips it.
In order to fix this you need to predict when that collision will happen and trigger it at correct moment.
Setting collision detection to Continuous as pixlark said might help if the swipe is not too fast.
Make sure that the collision detection mode for your Rigidbody2D is set to Continuous or Continuous Dynamic.
simple
go to the rigidbody of the object and change the c

Character vibrates while moving 30fps

I'm developing a 2.5D mobile game with Unity. In order to move the character back and forward I'm using a piece of code inside the update function:
void Update () {
if (shouldMove==true){
transform.Translate(Vector3.forward * 3 * Time.deltaTime);
}
}
So that code works pretty well when the game is running at 60 fps, but when the fps go down to 30 or less, the character starts to vibrate while moving. I've tried to test the same code with a plane terrain and it worked well, so maybe the problem is the collision between the character's and the terrain's colliders. However, I don't understand why if the fps are high it works well. I've tried both capsule collider and a mesh collider but no one has worked. What do you think? Should I try to use another code?
Edit 1: I'm using a capsule collider and a rigidbody. Should I use a Character Controller?
Sam Bauwens is absolutely right in his response, however, this issue normally is caused due to an excess of objects (specially those which are animated). This can worsen the performance a lot.
You should try to delete some of the objects and try if your character still vibrates. If it doesn't, that means that I'm right. Of course, you won't want to delete objects of your scene, so, you can add an asset such as SmartLOD that deletes the geometry of those objects that are not shown on screen and thus enhances your game's performance.
Hope it helps.
I had a similar problem with a ball that vibrates on the ground. It was caused by gravity which is pulling the gameobject towards the ground, then it collides on the ground and bounces. If your problem is the same as me, you have to either tune the Fixed Timestep (Edit => Project settings => time) and/or Bounce Threshold (Edit => Project Settings => Physics).
By increasing Bounce Threshold, you're going to increase the minimum speed below which an object won't bounce, so that the force of gravity won't be big enough to make the ball's velocity exceed the bounce threshold.
By reducing Physics time step, you reduce the impact of gravity for each time step because the time steps are smaller and therefore the amount of velocity added to the gameobject for each timestep is smaller.
EDIT: you can also look at sleep velocity (Edit => Project Settings => Physics), because if it is higher that the gravity velocity, the object shouldn't vibrate.

Constant orbit using physics in Unity3D

I am playing around with Unity3D and adding physics to the objects in my scene. I currently have a sphere (planet) in the center of the screen, and I have another sphere (moon) positioned outside of it that is not moving. When I run the game I want the moon to orbit the planet by applying a force to it. I have been able to get the force added by calling rigidbody.AddForce() and that will move it in the specified direction but it won't orbit. I'm not sure how to add force to it so that it will continuously orbit the sphere at a constant velocity.
I've tried some examples using a ConfigurableJoint and it orbits, but it starts out bouncing a little and then starts the orbit. My goal is to have a bunch of orbiting moons orbiting at their own speed that are able to bounce off eachother but not lose their velocity.
Any ideas?
Generally speaking you will fail, eventually, because rounding errors in your integration method will slowly throw you out of orbit. You can get very close in the ways suggested, but you could consider doing something more like the Kerbal Space Program, which seems to precalculate the orbit as an ellipse and then follow that ellipse until it has a reason to believe it should stop, rather than strictly "simulating" the orbit ...
If a collision occurs, allow normal physics to resolve the collision, and then recalculate your new orbit based on the result and start following that.
For the moon to orbit you would need to give the moon an initial velocity. Then have it accelerate towards the planet, that is a constant force.
gameObject.rigidbody.AddForce(1, 0, 0);
gameObject.constantForce.relativeForce = Vector3(0, 1, 0);

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