finding submesh in Unity 2017 - unity3d

How can I find submesh under my mouse NOT using Raycasting? Is any way to do it? I know how to do it clicking on object and using raycast but completely haven't idea how to id it without it. I need it because of bug in Unity - I can't update version of Unity, so I need to find any solution.

You can see if your mesh contains the mouse.
You get the position and the size of the mesh which allows you to create a square or a cube (whichever you need) and then you just see if your mouse fits within that square or a cube. If so, then you want to select that mesh.
https://tutorialedge.net/gamedev/aabb-collision-detection-tutorial/
or
If your object was a circle/sphere then you can perform a simple distance check between mesh's origin and mouse, if the distance is <= than the radius of the object, then you want to select that mesh.
http://cgp.wikidot.com/circle-to-circle-collision-detection
It is similar, just instead of using 2nd object, you are using a mouse.

Related

How to automatically create walls of a given height with collisions on the edges of auto generated AR plane in Unity?

I am working on an application that uses horizontal surfaces in AR. I don't have much experience with Unity but I was able to create automatically generated planes with which objects can collide (example: a falling and rolling dice). Unfortunately, sometimes such objects fall outside the plane area and fall into the void.
I would like to create something similar to invisible walls around the detected plane to keep the objects inside the plane.
Plane configuration i am currently using:
Application:
Edges of plane are marked with red line.
I think the term for what you are trying to do is geo-fencing. The easiest example is to put a square around the area your objects are contained where you have four conditions, one for each edge, like if objectX >= edgeX then objectX = edgeX and so forth. To do that in Unity you would probably have to mess with that C# language.

Standing inside an Object without clipping

My Application is a simulation of a 3D-Audio cage we have in our lab at uni.
To best simulate it, we made it a wireframe-sphere.
I need to be able to stand inside the cage, but if my Sphere is around my Camera, it clips, so it doesn't render until i move away.
I also need to be able to Rotate it, but not move it.
Is there a way to disable clipping for this case? What else can i try to get the desired result?
I've tried to set the clipping pane for the camera to 0, but 0.01 is the lowest it can be.
Also I've tried to use a transparent shader, both tries left me the same problem of the object clipping.
Object visibility when inside
Is there a way to disable clipping for this case? What else can i try
to get the desired result?
You can invert the normals of the sphere. Or model a sphere with normals on the inside and the outside if you want to look at it from both sides.
Another solution could be to use a shader with disabled backface culling (Cull off).
This stackoverflow answer might be helpful: Flip Normals in Unity 3D/spheres
Missing Manipulation Handler (MRTK)
If I understand the ManipulationHandler correct, you can make a smaller sphere with a ManipulationHandler inside the larger sphere and copy the transform changes to the larger sphere.
If you want to keep the larger sphere at the same place don't copy the position changes.

Unity all objects have same position

I have a 3d building model in my Unity project. It has many children like doors, walls etc. The problem is, all of the children points to same position in the Unity world (24.97, -2.08, 19.35). Their transforms show this position. And this position is far away from their actual one. How can i fix this?
I tried freeing all children from parent but this didn't change anything.
I want them to show their real position, which appears with move tool when we click upon them.
Here is the image link
It seems that this is simply their pivot point exported "wrongly" from the 3D editor your model was made with.
This won't change until you export it correctly from a 3D editor (Blender, Maya, etc).
Unity is not made for 3D mesh modeling and therefore in Unity itself you can't change the pivot points.
There is a very simple fix
Add a new empty GameObject
In the Inspector go to the Transform component, click on the context menu and hit Reset (you also simply set it to position 0,0,0 rotation 0,0,0 and scale 1,1,1) assuming the pivot should be at 0,0,0
Now drag and drop all objects into the empty GameObject
=> You have now one parent object with correct pivot.
By wrapping it in a parent object the childrens pivots don't matter anymore. You can simply do all translation, rotation and scaling on the parent object with the correct pivot and don't have to care about that "wrong" position at all.

Importing an exported .FBX from Blender to Unity object transform issue

Alrighty,
I have a dumpster model I have exported from Blender as an FBX. The transform, rotation and scales have all been applied in Blender. when importing into Unity and then adding to the scene, the model is elevated and rotated at an odd angle to the transform as per the image.
The model has an armature for animating the lids an I have applied the location, rotation and scale on it as well.
Any one else come across this or know of a fix?Thanks
Blender image
Incorrect dumpster transform and location image
The problem is that Blender uses the right-handed coordinate system which means the Z-axis is pointing upwards.
Unity uses the left-handed coordinate system which means the Y-axis is pointing upwards.
To fix this, set the X-axis rotation of the model to be -90. Press Ctrl+A and apply rotation. The X-axis rotation will look like it is now 0 after that. Set it to 90 again and export it to Unity.
This 3 minutes video should also help you do this if you are still confused.
If you still have problems, check your animation. Don't apply it to your model and see if it's the problem.
Also as a side note, you can use blender files (.blend) directly with unity. So every time you modify them inside your project folder they change in unity as well.
The simplest way to solve this would be as follows:
Create a dummy game object (D)
Transform/offset the position of D to make sure your object's position align with the dummy parent
Put your game object as the child of the dummy game object D
You can then apply transform on D, rather than your own game object directly.

How Does Unity Assign Pivot Point Location on Script Generated Meshes

I have tried to find any information on how the Unity assigns pivot points to object but all I keep finding is threads on how to move pivot points and that it can't be done. I am creating a 2D game with a background that is randomly created with meshes that are wrapped in empty GameObjects. These objects are organically shaped but they have a property that returns a rectangle that bounds the object so that they can be placed in a way that they are not overlapping. The trouble is that the algorithm assumes that the pivot point is going to be the center of the object. What I would like to know is how does Unity decide where the pivot point will be set to so that I can predict how much I will need to move my mesh inside the parent object so that the pivot point will be in the center of the bounding rectangle.
Possible fix:
Try create the meshes during runtime and see if it always places the pivot points at a certain corner or at least relatively speaking the same location.
If it does that you would know where the pivot point is and could take it into account in your code, if you also know the size of the mesh you spawn.
So I think most general and correct answer that I can come up with is that unity assigns the pivot point to the center of the GameObject that you apply the Mesh to. The local coordinates of the vertices of the mesh depending on how you create them mighht place your mesh so that its logical center is not the same as the that of the empty GameObject that it is attached to. What I did to fix the issue was to make a vector from local point (0,0,0) to the center of bounding rectangle and translate the vertices I use to make my mesh by that vector inverted. It wasn't perfect but by far close enough to ensure that I won't have any overlapping meshes.