# convexSweepTest(with:from:to:options:) Searches for physics bodies in the space formed by moving a convex shape through the physics world. ``` func convexSweepTest(with shape: SCNPhysicsShape, from: SCNMatrix4, to: SCNMatrix4, options: [SCNPhysicsWorld.TestOption : Any]? = nil) -> [SCNPhysicsContact] ``` ## Parameters `shape` A physics shape. This shape must enclose a convex volume. For details on creating shapes that satisfy this requirement, see [`SCNPhysicsShape`](/documentation/SceneKit/SCNPhysicsShape). `from` A transform matrix representing the initial position and orientation of the shape. `to` A transform matrix representing the final position and orientation of the shape. `options` A dictionary of options affecting the test, or `nil` to use default options. For applicable keys and the possible values, see `Physics Test Options Keys`. ## Return Value An array of [`SCNPhysicsContact`](/documentation/SceneKit/SCNPhysicsContact) objects describing any contacts that would occur when moving the physics shape through the physics world. ## Discussion Use this method when it’s important to plan for (or avoid) collisions ahead of the physics simulation. For example, in a game you might plan maneuvers for a flying character to fit through the gaps between static bodies in the physics world, as illustrated below: ```objc // Look for potential collisions along the spaceship's current path. SCNMatrix4 current = spaceship.transform; SCNMatrix4 upAhead = SCNMatrix4Translate(current, 0, 0, LOOK_AHEAD_DISTANCE); NSArray *contacts = [physicsWorld convexSweepTestWithShape:spaceship.physicsBody.physicsShape fromTransform:current toTransform:upAhead options:nil]; if (contacts.count == 0) { // Flight path looks okay. } else { // Flight path will cause a collision: look for another way around. } ``` --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)