Questions tagged [separating-axis-theorem]
The Separating Axis Theorem (SAT) is used to detect if two convex, generic objects are colliding or not.
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Separating axis theorem implementation results in limitless extending colliders along the Z axis
I am trying to implement SAT and it works except for the fact that colliders extend infinitely along the Z axis and I can never get past them. I also have confirmed that ...
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Collision normal for sphere near edge of triangle face
When my sphere (or bottom part of a capsule) moves with its bottom near the edge of a mostly horizontal triangle (a face of a heightmap), I am sometimes getting very bad (mostly horizontal) normals. ...
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Help finding bug in seperating axis theroem code
My collision detection is inconsistent. I am testing between 2 rectangles. When they are un-rotated, it says they are intersecting way before they touch, but when I rotate one, it works properly. I do ...
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Implementing Seperating Axis Theorem
I'm trying to implement the Seperating Axis Theorem by following this article I found on MDN.
Unfortunately, I'm not too geometry savvy and I wasn't able to find any good, simple implementation ...
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Separating Axis Theorem Duplicate Axis
I am building a physics game engine from the ground up and currently stumped with my SAT implementation. The situation I am having is in regard to Edge cases, if I remove all parallel / duplicate Axis ...
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Can I test for containment of convex polyhedra with the separating axis theorem?
I would like to refine the output of the separating axis test to not only tell me whether convex polyhedron A intersects convex polyhedron B, but also whether A is completely inside B. Is it safe to ...
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OBB vs Frustrum collision detection
Some definitions:
An oriented bounding box (OBB) is a rectangular block which can be represented in many ways, as a collection of eight vertices, a collection of six planes or others, for this ...
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Getting false positives with SAT
I've been trying to get proper collision detection with SAT in 3D. I started of with this post: How many and which axes to use for 3D OBB collision with SAT.
I've been trying to get the right axis to ...
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Calculate bounce and friction after a projection-based collision
According to the N Tutorials, after a projection-based collision (i.e, adding a minimum translation vector to an object's position in order to bring it out of collision), bounce and friction are ...
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Separating Axis Theorem is inconsistent
I recently implemented the SAT algorithm into my 2D game and at first it appeared to be working fine. However, when I move around and rotate the character in and out of the wall tiles, there are some ...
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Seperating Axis Theorom For Collision Detection issues
I have been attempting to use the SAT test to determine whether two of my convex meshes are colliding, however I've encountered are rather strange issue. The algorithm does determine whether the ...
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(Java2D) SAT Collision only works when shape is placed initially so it will collide
I'm working on a small 2D top down racing game and I'm trying to implement SAT collision into my game to detect collision between cars. So, I made a small little Java2D program to test the algorithm ...
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My collision detection code gives incorrect result
I am trying to use Separating Axis Theorem to check for collision between two shapes, but it's not working correctly. It's giving all incorrect results. The problem is in the collision-checking ...
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How to get the point of collision in Separating Axis Theorem?
I'm interested in the relatively precise point (not line) of collision for calculating angular velocity on impact for use in a impulse calculation. At first I thought, perhaps naively, that I could ...
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Zero vector test in projection intersection test in SAT
I stumbled across this implementation for a projection intersection test to use in a SAT test:
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Separating Axis Theorem - Calculate Normals from Points in 3D
So while researching for a method to detect collisions in a 3D space between (arbitrary rotated) boxes, I stumbled upon this excellent question with great resources for my further research and great ...
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How to calculate faces involved in collision (Separating Axis Theorem)
I have a game engine created in javascript (https://jsfiddle.net/4gqsq8wf/) which uses collision detection via the Separating Axis Theorem. Currently, it does not have any means of resolving velocity ...
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How do I find at least the closest penetrating point with SAT? [duplicate]
For more accurate simulations, I want to find the closest point of another polygon to one polygon's center when they collide. Is this possible with the SAT algorithm? Is it a good strategy at all for ...
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Separation of axis theorem implementation at normals
This might be more of a math question, but it relates to the development of a simple physics engine I am trying to create.
I have been stumped on this for about a week now, and have been unable to ...
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Vertical Collision Detection, Falling Through Ground
After much work trying to learn collision system theory and apply it, I've got my collision system working for the most part. The player can collide horizontally with no issue, sliding against walls, ...
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Calculating distance for Gauss Map optimized SAT
There's an optimization method for the separating axis test in 3D that uses Gauss Maps to discard certain redundant axes from the set of axes that need to be tested generated by edge-edge cross ...
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Collision detection 3d rectangles using SAT
This question builds on a previous post asked by griffinHeart nov 2012. See link below.
How many and which axes to use for 3D OBB collision with SAT
Refering to the explanation/answer by Ken.
What ...
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Separating Axis Theorem Issue
I am trying to create a 2d top down shooter using DirectX 11 (Windows 8 Store) and I am trying to implement OOBB collision using the Separating Axis Theorem.
However I appear to have run into an ...
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Collision detection circle-segment-segment
I've already implemented collision detection in my game loosely following this tutorial, which works great, but I realized there's one major flaw.
The player and the enemies are circles, while the ...
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Calculating contact points with SAT [duplicate]
After detecting a collision between two convex shapes by using separating axis theorem and calculating MTV. How can I calculate the contact points?(for applying torque to the rigid body).
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