Computing Bounding Box for buffer geometries in threejs

With the buffer geometry class in threejs there is a bounding box property that stores an instance of the Box3 class, and the compute bounding box method of the buffer geometry class is what can be used to create or update this instance of Box3. As the name suggests this bounding box property can be used for collision detection, but it can also be used to find out the size of a geometry which can aid in the process of positioning objects.

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Animation Loop Framework threejs project example

The subject of creating an animation loop is something that will come up a lot, not just with threejs alone, but indeed with client side javaScript in general. When it comes to client side javaScript alone there are methods like that of setTimeout, as well as request animation frame. There are also a number of additional features that are related to this sort of thing in client side javaScript, but also in the threejs library such as the THREE.Clock class, and thus also, and that the class works on top of. However in today’s post I am going to be writing a thing or two about a new javaScript module project that is a kind of framework that builds on top of the core idea of an animation loop.

This is then yet another threejs example project to add on top of the many others that I may continue to work on a bit more off and on in the future. I have a general idea of what I would like this project to be in terms of the core set of ideas. That is to have the usual code that I keep copying and pasting from one project to the next, abstracted away into a module, or framework kind of from which I would say is the case here with this project. That is that with this module I call a main create method and pass an object that contains a method that can be called to set up the scene, camera, and so forth, and then another that will update things over time.

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Using SVG for movement of objects threejs example module

For today’s new threejs project example post I started a new project this week in which I am looking into using SVG as a way to create paths that can then be used to define the movement and rotation of objects in a scene. The idea cam to be while working on my blog post for the SVG loader last week where I hit me that SVG is a pretty cool standard for creating paths. There is just one little problem which is that SVG is very much 2d, so to create a kind of 3d path with SVG I will need to think in terms of two paths for each 3d path. One path that I will be using to define motion for x and z, and then another in which I just use the y value for y in the 3d path.

If I can work out a decent enough system for creating 3d paths then they can be used as a way to update the position property of any object3d based object over time. This will mean mesh objects, but also any other kind of object3d based object such as a camera. Speaking of cameras there is also using these 3d paths created from SVG to update the rotation of objects as well by using the array of Vector3 objects for values to pass to the look at method of an object.

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The SVG Loader in threejs

There are a number of options for additional asset loaders in the Github Repository of threejs, one of which is the SVG Loader. Which is a way to go about loading a SVG file asset as an external file into a threejs project as a collection of paths that can then in turn be used to make Shapes. These shapes can then be used with somehting like the Shape Geometry or the Extrude Geometry constructors.

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threejs wrap module example for wrapping rather than clamping values

The vector3 class in threejs has a clamp method that will clamp a vector3 instance to a given min and max vector range that forms a box area of sorts. On top of this clamp method there is also a clamp length method that will do the same as the clamp method only with respect to the vectors unit length so it will clamp the vector to a sphere like area. In addition to that of the clamp methods in the vector3 class there is also a clamp method in the Math Utils object as well, but I am not seeing any wrap methods in the Vector3 class.

There are two general ways of going about treating boundaries one of which is to clamp them so that it is just not possible to continue out of a desired bounds, the other way though is to wrap them so that the value wraps around to an opposite side. I have wrote a post on the wrapping of the Vector3 class recently, but I thought that I should continue with this and make a more refined wrap module as a threejs example project which is what this post is about.

There are a lot of features that come to mind when it comes to wrapping values in threejs beyond just having a simple wrap value method that works well. There is having a method that will wrap a Vector to a box like area, but I would also like to have a method that is the wrap equivalent of that clamp length method as well. There are a whole lot of other classes beyond that of the vector3 class so I would like to have wrap methods that also work well with the Euler class that is the go to class for angles rather than vectors. Also there are many projects in which this wrap method, or similar methods for wrapping would be useful such as with my object grid wrap project.

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