How to develop a scrollview with inertia in Unity? - unity3d

I want to develop a "scrollview" in Unity.
Basically I have a Parent Game Object on the screen with many items inside it.
The Parent Game Object is big enough so it goes outside the screen.
I developed a scrolling script so when the user drags the parent object, I move it and it looks like scrolling.
I did this by implementing the OnMouseDrag event.
How can I calculate the inertia and apply it so when the user drags it fast, it continues to move?

What you want, the effect that you want, is called kinetic scroll/scrolling/panning .
Here is an answer with a generic algorithm in it, I'm sure that with this keyword in mind you will probably find a ton more of examples.
Next time watch out for the tags, your first set of tags was incorrect, other frameworks have the same unity name .

Related

Does changing multiple sprites on a single animation affect performance?

I have been building a 2D sprite based game for which I want to have the player be able to customize their equipment. This means that although I am fine with drawing the content, I'd need to ensure animations in the game run fine on top of each other. For this, I have been preparing a game object with several children to account for the equipment:
Each of the children runs a single animation and should have to follow the player, which I accomplish by using transform.localPosition = Vector2.zero; on the Update of the script each takes, so they hook to the parent's pivot and follow the player. While this has worked for the most part, there are moments in which all of the objects are not synchronized and as such sometimes the parent object (the body) is seen where it shouldn't since the other game objects should render on top:
Aside from that, to make it easy for the children to follow the parent position I had made sprites which are all the same size, which risks me having to load a lot of transparent space per sprite.
Another problem that I just noticed as I'm trying to address the issue of loading too many useless pixels involves the positioning with other objects such as the Sword game object, which doesn't follow the player fully if I use sprites that are not perfect squares (see this question for details How to align sprites of smaller sizes to a moving gameobject sprite? and this one Sibling sprite doesn't appear to follow main GameObject sprite even when transform.position updates)
I tried to fix this by making the Sword a child of the Hero, but even then changing the position through a function that sets values to add on to transform values of the sword game object only change the position of it relative to the initial value. I attempted changing the pivot of the sword sprites to a custom value to guess where the center of it would align with the main game object and appear in the right position, but even that doesn't seem to work.
I'm kind of getting tired with my current process, as I have to rely on several animations for each of the game objects, both parent and children, so that these obey to different layers in a single animator (or in the case of the sword, a separate animator), all to ensure there is some synchronization that doesn't always occur:
I really don't mind the web that is turning out in what I'm doing, but the fact that I have to repeat it across multiple layers with no real guarantee that all the objects would appear right on top of each other due to the fact of having multiple animations playing, and loading multiple sprites with empty space is becoming more of a chore than enjoyment.
So I think I came up with a possible solution: If I could make a single animation for the whole equipment used at any given point (whether only wearing pants or wearing full equipment), then having this single animation could guarantee synchronization across parent and children without the need for animator layers or special functions to update position or worrying about pivots or square sprites if I can set the position of non-square sprites in the animation, with the downside that I would need to account for every single animation for each possible equipment variation (so if I had even 3 of each sword, pants, boots, etc. that would mean 3^6 animations) and make a more complex web of animator states. The only thing I'd be worried about in this case, however, would be the performance, if having too many animations for a player would affect how fast these load. But at the benefit of eliminating the other problems mentioned, my question boils down to this:
Is it better to have a single game object with animations that change multiple sprites across children game objects and a single animator that chooses states based on multiple variables, or game objects with multiple animations that change a single sprite for each, and a single or multiple animators with multiple layers that choose states based on multiple variables?
There isn't really a set answer for something like this. It really just depends on how good your/the players computer is when playing the game. Sorry if this isn't what you wanted.

How to detect UI Objects from Main Camera object when using Google Cardboard VR SDK for Unity

When using Google Cardboard VR SDK for Unity, how can I detect when the Main Camera object looks at UI objects inside Canvas? OnPointerEnter() and OnPointerExit() happens when I look at 3D Objects in the samples project that Google offers, but there is no way to do it for UI Objects.
Based on your explanation, I guess you have set the Render Mode of your Canvas to Screen Space-Overlay or Screen Space-Camera. When you use one of these render modes, the position of your Canvas on the screen will never change, so you can never catch any element of the UI unless its bound includes the middle point of the screen. why? because you are using google VR and you have no joystick or something similar to control the cursor's position, therefore the cursor position is always (0, 0).
Let's assume the cursor and Canvas, both, are children of your camera. You can move your camera by shaking your head, this way the canvas and the cursor move in comparison with other objects in your virtual world based on camera movement, but they never move in comparison with each other.
So what's the solution? I think you can set the Render Mode of your canvas to World Space. This way your canvas will be an object in the world that the cursor can navigate through it. I know you think it's weird, cause likely you want to always see the canvas just in front of your eyes. So I think you just have one solution:
Do not change the Render Mode of the canvas, locate All UI elements on the canvas, it's better to locate them near the edges of the screen and also with adequate distances, then write a script to do this: When the cursor is moving, calculate the direction of movement and find out which UI elements could be the target of this movement, move it towards the middle point of the screen, when its bound includes the middle point, its OnClick will be called. After that, you must return all UI elements to their early positions. Also if the cursor stopped moving before the UI element reaches the middle point, you must return all UI elements to their early positions.
I know, it's so hard to handle this, but it's the only way I could propose.

How to create a custom height snapping tool in Unity Editor

I am making a strategy game and I need to have a tool which places the objects above the terrain while I am dragging them in Unity Editor when I work on level design.
Basically I want to get result like here:
https://www.youtube.com/watch?v=YI6F1x4pzpg
but I need it to work before I hit the Play button in Unity Editor.
Here is a tutorial
https://www.youtube.com/watch?v=gLtjPxQxJPk
where the author of it made a tool which snaps the object to the terrain height when a key is pressed. I need the same to happen automatically whenever I place an object over my terrain. And I want my tool to adjust the Y position of the object automatically even while I am dragging it inside of the editor.
Also just to clarify: I don't need grid snapping and I don't need this functionality during the gameplay. I just need to have a tool for my level design work.
Please give me a clue where to start with it.
Thanks!
There is this tag you can apply to classes so they do call their regular events during editor mode already: https://docs.unity3d.com/ScriptReference/ExecuteInEditMode.html
A trivial way then would be to apply this to a special class/object which regularly "finds" all objects from the game object hierarchy. Then it shall filter that list for the ones you want to snap to the axis and enforce their Y.

VR: How to form hands around object they are holding in Unreal?

I'm working on a VR project in Unreal and I'd like my player hands to form to certain objects whenever the user grabs them. (I.e. the way our hands work) Unfortunately, I haven't really found any examples online of others doing this.
For example, I'd like when the user picks up say a hand held tool like a hammer that the hand would wrap around the handle. When the user grabs a basketball the hand shouldn't be closed but, expanded like a you would if you were to palm a basketball in real life.
I haven't done a lot of testing with this but, I'm pretty sure since the hands are based off of a Animation Blueprint that they simply ignore collisions and follow the animation.
I guess the simplest solution would probably be based off of collision where the hand plays an animation and as the fingers of the hand wrap around the object they stop at that position where they collide with the object in question. If it is even possible that is.

Using unity animations globaly

I am trying to code an end for a level in a simple game. A lot of things need to happen at slightly different times. The character needs to do a celebration. Text needs to pop up on screen. The camera needs to move to show off the win, and finally there needs to be a scene transition.
This all seems like a great thing to solve with an animation. All these things could come in and act on specific key-frames, at the end raising an event and ending the scene.
The problem is it looks like animations have to be attached to specific objects. My camera, player, and the static global GameController are completely unrelated. In fact the global controller can't be related to anything. Because of that my animations don't see all the objects and can't control them. I am instead stuck writing synchronized animations, and code with a lot of yield return new WaitForSeconds(...);. I find this very difficult to manage, and seems like a lot of waste. Is there any way I can use animations, or some other frame based tool to globally animate my game?
Look into Unity's Timeline system. I believe this is exactly the sort of thing it was made for.