1
vote
1answer
102 views

Sphere-Sphere intersection and Circle-Sphere intersection

I have code for circle-circle intersection. But I need to expand it to 3-D. How do I calculate: Radius and center of the intersection circle of two spheres Points of the intersection of a sphere ...
4
votes
2answers
286 views

a flexible data structure for geometries

What data structure would you use to represent meshes that are to be altered (e.g. adding or removing new faces, vertices and edges), and that have to be "studied" in different ways (e.g. finding all ...
6
votes
1answer
615 views

Procedural Geometry Generation

I have recently been looking into SceneKit for OS X and noticed that there are several factory methods to create geometric shapes such as: Box, Capsule, Cone, Cylinder, Plane, Pyramid, Sphere, Torus ...
0
votes
1answer
543 views

Easy way to project point onto triangle (or plane)

I have a mesh of triangles (navigation mesh), and a point in 3d space. This point should be "over" one of the triangles all the times. I'm trying to determine which triangle is the one the point is ...
1
vote
2answers
701 views

Segment-Cylinder intersection

What is the complete code (C#, pseudo, does not matter) for calculating the resulting segment (or its absence) for the intersection of the segment and the cylinder? The segment is defined by ...
1
vote
6answers
424 views

Testing whether two cubes are touching in space

Does anyone have any clean ideas on testing whether two cubes in 3D space touch? By touch I mean, touch at corners or on a face or on an edge. Say that the cubes are axis aligned and there is no ...
3
votes
2answers
242 views

How to generate slopes that meet the plane, is using collision detection a good idea?

I have a terrain, which is defined by mesh. And there are a lot of other polygonal faces scattered throughout the terrain, they can be located above, or below or cutting through the terrain. You can ...
14
votes
2answers
3k views

How to find if circle and concave polygon intersect?

I have a polygon (sometimes convex, but often concave), and a bunch of circles with different radius. How can I find out if a circle is intersecting/overlapping with the polygon? If it makes it ...
4
votes
3answers
1k views

Point line collision reaction

I am trying to program point line segment collision detection and reaction. I am doing this for fun and to learn. The point moves (it has a velocity, and can be controlled by the user), whilst the ...