I am making a paper toss kind of game in Unity3d. I am implementing wind effect using constant force. I wanted to know how to make object fall in line with the target ie, if the object gets over the target, it should go in or fall in line with the target, not go behind or in front of the target. At present when I swipe applying a constant force, for different angles of swipe the distance moved by the object differs. Help would be much appreciated.
In FixedUpdate, use Physics.Raycast to check to see if the object is over the target. If so, set the x and z values of rigidbody.velocity to be zero (assuming y is the up/down axis in your game world) and disable the ConstantForce component (i.e. gameObject.GetComponent<ConstantForce>().enabled = false). Note that this won't be most realistic of movements, as it will seem like the object suddenly moves straight down when it goes over the target -- but it sounds like that's what you want.
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I've been looking for a solution to this for quite a while now (meaning several days) and I haven't found anything yet. Maybe I'm thinking about it wrong and there isn't a way, but let's try!
I'm recording hand-data on a Hololens (the Unity Hololens Input Simulation for now). This essentially gives me one float AnimationCurve for each hand joint for each transform.position.x to z and rotation.x to w. Now my goal is to put these curves into an AnimationClip and add it to an AnimatorController (via an AnimatorOverrideController) that animates a hand rig and replay the recordings. Everything so far works!
However, the recorded hand-data from the Hololens is in world scale, not in local scale. (which makes sense, since you usually want absolute coordinates when you want to know where the hand is.) But to animate the hand, it seems I'm only able to set local coordinates, which I don't have.
Example:
clip.SetCurve("", typeof(Transform), "localPosition.x", curve.PositionX);
Here, the clip takes the the x-coordinates from some hand joint and puts it to the localPosition.x of the corresponding hand rig joint. The problem: curve.PositionX is world-scale (absolute coordinates), but localPosition.x takes local-scale (coordinates relative to its parent).
I can't simply change "localPosition.x" to "position.x", like so:
clip.SetCurve("", typeof(Transform), "position.x", curve.PositionX);
even though the Transform class has both properties and position is the object's world scale position. I'm not sure why this doesn't work, but it gives me the following error:
Cannot bind generic curve on Transform component, only position, rotation and scale curve are supported.
I'm aware that it doesn't make much sense to use absolute coordinates for an animation, but I simply don't have anything else.
Does anyone have an approach how I can deal with this in a sensible, not-too-cumbersome way? It seems I have all the important parts, I just can't figure out how to put them together. Thanks so much already! :)
From my basic understanding, it seems like you are using the Input animation recording service provided by MRTK. Unfortunately, MRTK does not provide the localPosition version of Curves data. However, you can modify the data from the recordingBuffer after the InputRecordingService stops recording.
So, this is a method worth trying for you: in the handJointCurves dictionary property of recordingBuffer field, a set of pose curves is stored for each joint. And then, base on this table:Joint pose curves, subtract the position value of the key None from the position value of each other joint in every key frame so that the localPosition based on the key None is obtained.
I have been using Unity for a while and still Im not sure about some things, I know there are like 5 different ways to move our character (not using prefabs like for 1st or 3rd person controller I mean just code from scratch) so far for moving a character on a terrain I think setting the speed of the rigidbody works overal for me, just setting the x and leaving the y component as what it was before assigning that, so that gravity effect is kept, overal it works, I manage to collide with wall and other objects, manage to go on terrain and could add jump later in same fashion, but the trouble I find is that my character flies when it steps over any small object like a stone on ground, if he goes over it he starts flying, not a big distance but definetly looks like walking on the moon maybe, also I see that if I have a bridge that is lower in the middle part of it (like U shape) well the character goes like flying from the begining almost until the middle or so, as said works like being on the moon, however gravity seems ok on other objects, I know I can change the gravity value to be higher but Im affraid I could be breaking all that so my question is, is there a better way to move a character on ground that will work better without changing the gravity value? I guess that it can work right without affecting this value, I used other method to change velocity and adding a certain value to the y component but again I see it not right as an apparent correct value for small stones and small objects makes it hard to go over slopes too, any help is greatly welcome =).
I have a cube with Rigidbody attached to it would slide slightly whenever I pressed the play button. If I leave it for awhile, it would slide to other side of the screen.
Anyone know how to solve this problem without using the "freeze position"? I don't know what I messed up in my project...
This is what the object looks like:
Note: I need to use the gravity.
Thank you!
Heh! The solution here is:
You had a rigidbody on the floor :)
You don't do that :) Never.
If the "floor" surface is flat, then,
it will not slide.
You've got something strange going on, such as
"floor" is NOT flat
a feature like "Wind" turned on
perhaps other objects invisible in the scene you have forgotten about are nudging it
PhysX does not have a "mind of it's own". There is some simple reason it is moving.
Let's say the "floor" is indeed on an angle, so it SHOULD move, but you WANT it to NOT move.
What you obviously do:
Just as in the real world, put something there to stop it moving.
A small invisible wall will do the trick. That's PhysX!
Usually rigidbody sliding happens when a lower rigidbody has lower mass than a higher rigidbody (forcing down the lower rigidbody). Typical problem with player having say mass 80 jumping on a cube with mass 1. In this case the collision is so violent that the cube will probably fly out (not only slide).
The situation is very similar to the real world. Try to stay on a box of milk if you have 120 kg (ok, ok, 80 :) ).
When you try to eliminate this behavior, you need either increase the mass of the lower object or decrease the mass of the higher one or set the lower rigidbody to kinematic.
The solutions above is not proper way of solving the problem. Unity has more features of physics than mass. If you get sliding on movement or because of other objects you should add proper drag value on your rigidbody. For example , lets say you have blocks spawning over top of other blocks and this creates horizontal sliding. In my case I add drag of 1 to the objects which has mass of ~ 1 kg. It depends on the scene and you should try different values on your case. Do not use bigger values and angular drag if it is not important.
I do not understand, why jointed object can't look at target.
Example: 2 boxes with hinge joint (anchor is at the touching place) and a target object. When I say A-box to lookAt target, I think it will just turn on X-axis. But both of the boxes start to shake. Why?
Take a moment to reflect on what a call to LookAt is trying to do.
It's rotating the transform while ignoring physics.
That's bound to create problems, since you're not rotating the whole system, you're moving one part of it. Your rotation with LookAt is "fighting" with the adjustments the physics system is trying to make.
To solve that conflict you can do one of the following:
Rotate the entire system (both cubes). This will involve putting them all under one transform, and having that transform rotate.
Use a physics-based approach. It won't be too hard, but won't be as simple as a function call. You'll probably need a simple PID controller such as the one outlined in this thread.
I'm using the first person controller for my characters movement. On a left arrow keypress, I'd like the character to instantly rotate 90 degrees and keep moving forward. Currently, when I hit the arrow key, the character makes the sharp 90 degree turn, but the forward momentum the character previously had takes a second to wear off so the character ends up sliding in the direction he was previously moving a short bit.
The closest example I can think of to visually explain what I'm trying to do is how the character turns sharp in Temple Run. How my game is currently working, if I had the character on a ledge make a sharp left turn, he'd likely keep the original momentum and slide off the edge right after he turns.
Since my character is running on the x/z axis, I'm wondering if there would just be some way to maybe swap the directional velocity/momentum? The speed the character had on the x axis would instantly be switched to the z when it turns and the other would be set to zero. I'm obviously open to any solution that accomplishes what I'm looking for.
I dug into the CharacterMotor class in the first person controller, but have yet to find what part I can tweak to accomplish this.
I'd greatly appreciate any help.
Thank you.
You can try to stop the velocity of the Rigidbody before turning.
this.rigidbody.velocity = Vector3.zero;
this.rigidbody.angularVelocity = Vector3.zero;
If you want the object to continue like it did, you can try playing around with it by saving the current velocity in a variable, setting it to 0, rotate it and then putting back the old velocity (still forward).
If it works with global vectors (so from the point of view of the world, not the object), then you can try negativing the velocity, actually causing it to go 'backwards'. I can't test it for now but either way I think you need to set the velocity to zero first before turning the character.