11
votes
Accepted
How to use the SDL viewport properly?
My guess is you're trying to implement a camera, and should not be using SDL Viewports. The viewports are for UI elements like menus, minimaps, etc. It's a way of dividing up the screen into multiple ...
- 6,046
10
votes
Accepted
Is a custom coordinate system possible in Unity
If what you want is to bypass the floating inaccuracy caused by single point precision problem, for the sake of creating bigger environments for your game, then it depends on what you are willing to ...
- 4,907
9
votes
Overcoming float limitations for planet-sized worlds in Unity
That's a question that frequently pops up. I will take the liberty to forward you to another fairly detailed answer I already gave to the same issue, instead of just repeating it here: Is a custom ...
- 4,907
8
votes
Accepted
Get local coords from global coords
The point P to be transformed is, in homogeneous coordinates:
$$
\begin{pmatrix}
50 \\
40 \\
1
\end{pmatrix}
$$
The homogeneous transformation matrix M is (using \$cos(\frac{\pi}{4}\$) = sin(\$\frac{...
- 2,111
7
votes
Accepted
Overcoming float limitations for planet-sized worlds in Unity
You're thinking in very static terms.
Just because an object is half a world away doesn't necessitate any issues. If entity coordinates are stored relative to chunk rather than relative to world, ...
- 29.4k
6
votes
How can I randomly generate objects inside of a Complex Area?
Triangulate the area.
Pick a random triangle.
Generate a random point inside that triangle (link).
- 86
6
votes
Accepted
Finding all hexagonal grid coordinates inside cover arc
I prefer to do hex-cell coordinate math in what Amit calls cubical coordinates on your linked page. For the rest of this answer, (X, Y, Z) will refer to cubical coordinates.
Basically, for any of ...
- 9,029
6
votes
Accepted
How to raycast down to the floor plane to determine world space coordinates in Godot
I'm not sure I understand your limitations, so I will give you a few approaches, and hopefully this gets you to the solution along the way.
This is not an exhaustive list.
Pickable Object
If you have ...
- 25.2k
5
votes
Accepted
Finding a tile number in a grid system
The only way I know of, or at least can think of right now, is the following:
Prerequisites:
You need to know the width and height of your grid
the tile numbers must increase successively, so like ...
- 163
5
votes
Convert quaternion to a different coordinate system
Summarizing your two coordinate spaces:
...
- 132k
5
votes
Accepted
Handedness of 2D coordinate systems
It entirely depends on what you want to do with it and both have reasons why they exist.
The one where the top left corner is the origin and the positive xes point away from them are based on the way ...
- 14.8k
4
votes
Is a custom coordinate system possible in Unity
I doubt that there's a way to change the coordinate system Unity uses internally for its transforms/physics/etc. Not without recompiling the engine source at least. But that may not be necessary to ...
- 132k
4
votes
Accepted
LibGDX Overlay Game with Stage
You need to project from the worldspace to screen space using the correct camera, not the project method on the Vector2. Then ...
- 4,461
4
votes
How can I randomly generate objects inside of a Complex Area?
This might not be the most elegant solution, but it might work for you:
Define that shape as a PolygonCollider
Get the bounding box of that collider (...
- 118k
4
votes
Accepted
Why does the Debug.DrawRay return these weird lines
You're drawing Rays, not Lines. This means that the second parameter is a direction not a point in space.
https://docs.unity3d.com/ScriptReference/Debug.DrawRay.html
Draws a line from ...
4
votes
Accepted
How to convert a 4x4 matrix transformation to another coordinate system?
This is as easy as writing your old coordinates in terms of the new ones.
We want +x to map to +x (1, 0, 0)
We want +y to map to +z (0, 0, 1)
We want +z to map to -y (0, -1, 0)
We want the fourth, ...
- 132k
3
votes
clamp a 2D coordinate to fit within an ellipse
Here's a general method to clamp a point \$A\$ to the ellipse of center \$C\$ and half-dimensions \$d\$ (i.e. the ellipse is \$2d_x\$ wide and \$2d_y\$ high):
\$B = \frac{(A - C)}{d}\$ gives you the ...
- 1,168
3
votes
Overcoming float limitations for planet-sized worlds in Unity
Not sure if you have already settled for a solution, but I'd like to mention two other resources that might be useful to you and other readers in the future.
This recent CppCon talk: "Demystifying ...
- 3,057
3
votes
how to create an outlined polygon with vector3 coordinates?
1)Find barycentric coordinates
for(int i = 0; i < verticesInPolygon; i++)
{
bary.xyz += vertices[i].xyz;
}
bary.xyz /= verticesInPolygon;
2)Create new ...
- 1,423
3
votes
How do I get the 3d coordinates of my model Instance? [LibGDX]
Try something like:
Vector3 position;
position = modelInstance.transform.getTranslation(new Vector3());
This gets the position and stores it in the ...
- 7,800
3
votes
Accepted
How do I convert positions between local coordinate systems?
What you have is the basics of 3D math, without any rotation. In 3D, we generally refer to an object's position as its translation, and set of things that describe its position (its translation, and ...
- 1,319
3
votes
Accepted
3
votes
Accepted
Convert global 3d coordinate system to a local one with specific direction
Construct a matrix like so, where each vector is one column of the matrix:
[ House's X+ direction | House's Y+ direction | House's Z+ direction | House's position]
The fourth row should be [0, 0, 0, ...
- 132k
3
votes
Accepted
Alternatives to Camera.main.ScreenToWorldPoint in Unity
Basically, when you call Camera.main, Unity internally uses the FindGameObjectsWithTag to search through all of the objects in ...
- 694
3
votes
Accepted
How to invert a Tilemap's coordinate system?
It might be smarter to work with unity instead of against it and just accept how its coordinate system works. Keep in mind that this coordinate system follows the same "y is up" logic as the Unity ...
- 118k
3
votes
Algorithm to check whether pizza toppings are divided half-and-half
After getting help from @DMGregory I was able to solve this by :
Getting the center of the toppingsA and toppingsB
Finding 6 most far toppings from the centers
generate 2 polygons based on these 6 ...
- 151
3
votes
Accepted
Ensure that random enemies don't spawn just near the player
The simplest system I can think of consists in testing the position of the new enemy before your screen.blit(), like so:
...
- 66
3
votes
Accepted
LookRotation function for Z-up, right handed system
First, we can transform your coordinates into Unity's coordinates:
...
- 132k
3
votes
Should the coordinates, and rotation angles of all the sprites be stored in variables?
Storing values in variables is not the same thing as using magic numbers. The magic number anti-pattern is a direct usage of a number in the code.
For instance, compare the following code snippet:
<...
- 11.5k
Only top scored, non community-wiki answers of a minimum length are eligible