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The Separating Axis Theorem (SAT) is used to detect if two convex, generic objects are colliding or not.

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I am trying to do a SAT OBB collision test using OBBs that are represented as a 3D position (\$c_0\$ and \$c_1\$) and a 3x3 rotation/scale matrix (\$A\$ and \$B\$), where the columns of the rotation ...
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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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I am currently working on a basic HTML, CSS, and JavaScript game as a freshman high school summer project. I am currently trying to implement separating axis theorem (I spent a lot of time learning ...
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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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I am doing SAT in 3D, right now just between cuboids/3D rects (idk the terminology). I have intersection working fully, and static collision works as long as the projection axis is not zero. But if it ...
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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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I implemented SAT alghorithm that is able to detect collisions and return shortest "pull out" vector. On the screenshot below this vector is determined by yellow color (P and Q). If I add Q ...
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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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I am trying to detect collision between two triangles using Separating Axis Theorem however I am unaware what is wrong with my code. The CollisionHelper::isTriangleIntersectingTriangle is called every ...
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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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Currently I have a working 2D SAT collision system with only boxes, but works with static rotations as well, leaving room for triangles. One of the issues I've been able to resolve was tunnelling, ...
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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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I am trying to implement SAT collision detection between 2 OBBs, however, I am getting a lot of false positives, can anyone help me figure out what I am doing wrong, thank you in advance. This is my ...
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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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I'm making a 2D platformer game and using the separating axis theorem for collision detection, but I want the player to be able to walk along the ground and slide on walls and other stuff and I can't ...
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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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I am using convex decomposition with SAT (separating axis theorem) and I generate two arrays of convex pieces, How do I submit my arrays to my collision detection method which only takes two arguments....
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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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Quick question which hopefully won't require thralling through my code. I have a working implementation of SAT for 3D collision detection but I'm having some problems with dealing with rotated ...
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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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So I was just doing an example 2D SAT collision detection problem on paper when I encountered something unexpected. I ran the algorithm on a triangle and a square, and the result of the algorithm was ...
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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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I'm using the seperating axis thereom for discrete collision detection. I have code to find the minnimum translation vector (or distance) to seperate two shapes but how can I adjust it to get a vector ...
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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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I´ve been following this tutorial : http://www.dyn4j.org/2010/01/sat/ to help me understand and implement the SAT for collision detection in my games as I want to add a support for polygons. However, ...
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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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Suppose there are two quadrilaterals A and B. A is stationary but B is moving. They collided. Now B is inside A. To check if they are intersecting I can use 2d separating axis theorem (SAT). To ...
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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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I am working on a project in which I have implemented the Separating Axis Theorem to detect collisions between objects. My current collision response is an object that contains whether it is ...
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I stumbled across this implementation for a projection intersection test to use in a SAT test: ...
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I'm trying to learn about 2d polygon collision detection/handling and have ran into a snag. After running through lots of tutorials and sample code I've attempted to implement my own polygon class ...
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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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In the 2D SAT collision determination algorithm, you project the convex polygons onto each potential separating axis. Supposing the polygons intersect, from what I understand, the axis for which the ...
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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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I am having a bit of difficulty detecting collisions properly with separating axis theorem. My code seems to be giving a lot of false alarms. Also, I've looked into implementing sliding collisions ...
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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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I have a collision detection/resolution implementation that uses the Separating Axis Theorem. Detection and such works perfectly fine, as well as resolution for most objects/shapes in my game. ...
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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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I am currently implementing a separating axis theorem collision response. It can be used by oriented bounding boxes and axis-aligned bounding boxes. So far I have covered face-something contacts. I ...
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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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My platformer has both rectangular tiles and right-triangle slopes with rectangular hitboxes. My sprites are also rectangular. Collision with only rectangular tiles works well. Even if there are ...
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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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I implemented collision detection in my game using SAT. The detection works, but I'm trying to use the algorithm to figure out the penetration vector of the two OBBs and push them apart (before doing ...
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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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I made a post yesterday to see if anyone could understand my problem. However I did not receive much guidance, probably because my question was not clear. I have worked on it a little more and ...
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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 ...
Nick's user avatar
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RI have a pretty standard SAT algorithm that seems to successfully be detecting collisions but now I am looking for some assistance in finding the shortest line between 2 separated Polygons. I ...
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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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I am attempting to implement the separating axis theorem in C#. I have a function that can calculate the minimum translation vector between two polygons. However, I can't seem to create a function ...
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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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