rotational-matrices

Shear Matrix as a combination of basic transformation?

℡╲_俬逩灬. 提交于 2019-11-29 14:49:33
问题 I know the transformation matrices for rotation, scaling, translation etc. I also know the matrix for shear transformation. Now, I need to have the shear matrix-- [1 Sx 0] [0 1 0] [0 0 1] in the form of a combination of other aforesaid transformations . Tried searching, tried brainstorming, but unable to strike! Thanks! 回答1: The x-shear operation for a shearing angle theta reduces to rotations and scaling as follows: (a) Rotate by theta/2 counter-clockwise. (b) Scale with x-scaling factor =

How to calculate extrinsic parameters of one camera relative to the second camera?

痴心易碎 提交于 2019-11-29 10:14:24
I have calibrated 2 cameras with respect to some world coordinate system. I know rotation matrix and translation vector for each of them relative to the world frame. From these matrices how to calculate rotation matrix and translation vector of one camera with respect to the other?? Any help or suggestion please. Thanks! First convert your rotation matrix into a rotation vector. Now you have 2 3d vectors for each camera, call them A1,A2,B1,B2. You have all 4 of them with respect to some origin O. The rule you need is A relative to B = (A relative to O)- (B relative to O) Apply that rule to

Why are quaternions used for rotations?

孤街浪徒 提交于 2019-11-28 15:10:35
I'm a physicist, and have been learning some programming, and have come across a lot of people using quaternions for rotations instead of writing things in matrix/vector form. In physics, there are very good reasons we don't use quaternions (despite the bizarre story that's occasionally told about Hamilton/Gibbs/etc). Physics requires that our descriptions have good analytic behavior (this has a precisely defined meaning, but in some rather technical ways that go far beyond what's taught in normal intro classes, so I won't go into any detail). It turns out that quaternions don't have this nice

How to calculate extrinsic parameters of one camera relative to the second camera?

社会主义新天地 提交于 2019-11-28 03:44:05
问题 I have calibrated 2 cameras with respect to some world coordinate system. I know rotation matrix and translation vector for each of them relative to the world frame. From these matrices how to calculate rotation matrix and translation vector of one camera with respect to the other?? Any help or suggestion please. Thanks! 回答1: First convert your rotation matrix into a rotation vector. Now you have 2 3d vectors for each camera, call them A1,A2,B1,B2. You have all 4 of them with respect to some

Three.js: Show world coordinate axes in corner of scene

与世无争的帅哥 提交于 2019-11-27 20:48:05
This is probably a very basic problem, but I haven't found a solution yet and it's been bugging me. I'd like to show arrows indicating the world coordinate directions (x, y, z) in the bottom right hand corner of the camera like is done in Maya, so that when rotating the camera around an object, or moving through a scene, you can still identify the directions of the world coordinates. I've tried to accomplish this using two different approaches and neither has worked so far. I have an object with three arrows as children using the THREE.ArrowHelper class, we'll call it XYZ for the moment. The

Three.js: Show world coordinate axes in corner of scene

无人久伴 提交于 2019-11-27 04:28:08
问题 This is probably a very basic problem, but I haven't found a solution yet and it's been bugging me. I'd like to show arrows indicating the world coordinate directions (x, y, z) in the bottom right hand corner of the camera like is done in Maya, so that when rotating the camera around an object, or moving through a scene, you can still identify the directions of the world coordinates. I've tried to accomplish this using two different approaches and neither has worked so far. I have an object