Graduate student Xuan Luo has developed a pretty damn amazing Pepper’s Cone effect using stuff you probably have lying around your house right now: some clear plastic (a cup will do), an iPad, and a nickel. 

If you try to reflect a normal image into a cone or pyramid, as the above video shows, it’ll warp and not work from all viewpoints. Working with Professors Jason Lawrence and Steven Seitz, Luo has put together an algorithm that pre-warps the image being projected, so that it looks perfect in the 3d display regardless of the point from which it’s viewed. From the description:

This display allows viewing a three-dimensional object from any direction over a 360-degree path of travel without the use of special glasses. Inspired by the classic Pepper’s Ghost illusion, our approach uses a curved transparent surface to reflect the image displayed on a 2D display. By properly pre-distorting the displayed image our system can produce a perspective-correct image to the viewer that appears to be suspended inside the reflector. We use the gyroscope integrated into modern tablets to adjust the rendered image based on the relative orientation of the viewer. Our particular reflector geometry was determined by analyzing the optical performance and stereo-compatibility of a space of rotationally-symmetric conic surfaces.

The effect is remarkable, even supporting animation and audio. The code for the algorithm has yet to be released, but will be open sourced when it is. Check out the project page for more detailed information, or to sign up to be informed when the code is available. If you’re more tech-minded, you can read the full details in the project’s PDF. 

Every iOS rollout from Apple introduces new features we eventually can’t live without, but they almost always break something, too. In the case of iOS 11, it’s making it difficult to perform TOXIC, a trick that uses the calculator on a borrowed phone. The new operating system changes how the calculator is displayed, which ruins the trick. Fortunately, a discussion over on the Magic Cafe forums has provided a solid workaround. 

If you only need to do basic multiplication you can get away with only +0x0 and no bracket in the event the screen won’t rotate.
As you enter in each value and press “x” the total will show “0” but the force number will show at the end when you press “=”.
A good workaround if you are already in the middle of a routine and can’t start over.
For a more full featured toxic app using your phone have a look at iThump with TOXIC+. 

iThump is a hefty $29.99, but it would appear to solve the iOS issue quite tidily.