A branch of mathematics concerned with questions of shape, size, relative position of figures, and the properties of space.
1
vote
2answers
427 views
Rotating coordinate system
Lets say that you want to rotate simple cube around fixed point in center.
Is it possible to use such coordinate system, that you need to use only sine and cosine in order to rotate?
I have done ...
5
votes
2answers
846 views
Generating geometry when using VBO
Currently I am working on a project in which I generate geometry based on the players movement. A glorified very long trail, composed of quads.
I am doing this by storing a STD::Vector, and removing ...
0
votes
3answers
289 views
exact point on a rotating sphere
I have a sphere that represents the Earth textured with real pictures.
It's rotating around the x axis, and when user click down it has to show me the exact place he clicked on.
For example if he ...
9
votes
2answers
6k views
converting a mouse click to a ray
I have a perspective projection. When the user clicks on the screen, I want to compute the ray between the near and far planes that projects from the mouse point, so I can do some ray intersection ...
1
vote
2answers
2k views
Voronoi regions of a (convex) polygon
I'm looking to add circle-polygon collisions to my Separating Axis Theorem collision detection.
The metanet software tutorial (http://www.metanetsoftware.com/technique/tutorialA.html#section3) on ...
13
votes
2answers
2k 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 ...
1
vote
0answers
293 views
How can I draw a model perpendicular to a sloped surface? [duplicate]
Possible Duplicate:
How do I find rotation in 3D based on a vector/normal?
My models are axis-aligned. I know the normal of the surface I want to draw them on.
How do I compute the ...
1
vote
1answer
254 views
Frenet frame and application
I have just been reviewing Frenet Frame math. It is an interesting geometrical issue.
I know that common applications are:
camera movement along a curve
tube and ribbons surface
Can someone ...
4
votes
3answers
902 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 ...
3
votes
1answer
1k views
Morph a sphere to a cube and a cube to a sphere with GLSL
I'm getting started with GLSL with quartz composer.
I have a patch with a particle system in which each particle is mapped into a sphere with a blend value. With blend=0 particles are in random ...
3
votes
1answer
2k views
How do I find rotation in 3D based on a vector/normal?
I've been playing with Blender and Python, doing basic things like accessing vertices/normals,etc.
I can get the normal of each face of a mesh. I was wondering, how can I get the rotation of a face ...
6
votes
4answers
983 views
Implementing 2D CSG (for collision shapes)?
Are there any simple (or well documented) algorithms for basic CSG operations on 2D polygons?
I'm looking for a way to 'add' a number of overlapping 2D collision shapes. These may be convex or ...
