Questions tagged [sphere]
A geometric primitive in which all points have the same distance to a midpoint.
89 questions
0
votes
1
answer
64
views
Is an assumption of Welzl’s algorithm valid?
The stated assertion that a point outside some intermediate Minimum Enclosing Sphere is on the boundary of the final Minimum Enclosing Sphere seems unsupportable. It is true only for the first point ...
7
votes
1
answer
1k
views
Why are collision manifold points created inside objects instead of on their surfaces?
Suppose you have two overlapping spheres \$A\$ and \$B\$, with centers \$c_{A}\$ and \$c_{B}\$ and radii \$r_{A}\$ and \$r_{B}\$. Let
\$n = \operatorname{normalize}(c_{B} - c_{A})\$ be the collision ...
- 73
1
vote
1
answer
126
views
Why is my raycast not working?
I'm trying to ray-cast mouse clicks to the surface of a sphere (from which point, I'm going to get the coordinates of the vertex of the sphere's mesh that are closest to the click). The following ...
- 474
0
votes
1
answer
113
views
Variable subdivision creating artifacts
I'm currently implementing a method for subdividing an icosahedron found here that isn't quite working as expected due to the artifacts created (and the way the triangles are oriented)
The problem ...
- 47
0
votes
1
answer
242
views
How to live on sphere?
What I want to achieve
I want to generate sphere planet world, seamless of course, for RTS game like Planetary Annihilation: TITANS, which means I want:
place walking agents on sphere, move them on a ...
- 13
1
vote
2
answers
314
views
Seam visible on sphere or torus made in Blender when using a texture atlas
I'm making a game in OpenGL with C++.
I have a problem with my vertices or texture coordinates - there's a seam visible on the sphere where the texture wraps around:
If I use "nearest" ...
- 13
0
votes
1
answer
179
views
How do I determine which pixel is under the cursor when looking at an equirectangular image through a camera?
I am working on a game. The camera is freely rotatable by the user. The background is displayed from an equirectangular image. I need to know which pixel of the background image is located under the ...
0
votes
0
answers
123
views
How to fix distortion when wrapping heightmap around sphere
I currently have a 3D model of the moon. You are able to pick a point on the moon and it takes longitude and latitude coordinates of that point and generates a mesh based on the heightmap. So if you ...
0
votes
0
answers
146
views
Why are there gaps in my fibonacci sphere?
I recently took an interest in sphere topologies to find which one is the best. The most popular one seems to be the fibonacci sphere. So I went and did some research and found some C code online that ...
- 47
0
votes
1
answer
166
views
How to compute visible area of a sphere
I have a number of spheres in my scene. I also have another object that I want to scale depending on the amount of a selected sphere that is visible (it can be occluded by multiple other spheres ...
- 141
0
votes
1
answer
203
views
How to scale down noise intensity?
I'm currently making a planet and for that, I added noise, to create terrain on the surface. The method I'm using is creating simplex noise (that ends up looking like the image below)
And I write ...
- 47
1
vote
1
answer
771
views
How to subdivide an octahedron into a sphere?
For a game I'm making, I have to tessellate an octahedron into a sphere on the GPU (shaders). What I've done is I've successfully tessellated the faces, but I'm having trouble subdividing more spaces, ...
- 47
0
votes
1
answer
202
views
Help understanding the math to position sphere vertices by latitude and longitude
For a project of mine, I need to render spheres without loading a pre-made model or using built-in functions.
I found this bit of code on the internet that seems to work but I really want to ...
- 47
1
vote
1
answer
1k
views
Cube Mapping vs Spherical Mapping
I am currently researching the difference between Cube Mapping and Spherical Mapping.
Wikipedia says the following:
In the majority of cases, cube mapping is preferred over the older method of sphere ...
- 113
0
votes
1
answer
108
views
How would I calculate the velocity of a sphere with an impulse applied at the top?
I'm developing a rigid body physics engine and currently have accurately calculated the angular velocity of the sphere when impulsed. Unfortunately though, I'm not calculating the velocity correctly ...
- 1