Organizing QR Codes

I have some deeper questions about tracking with Fologram.

A QR code created with the FologramQR command shows the following text: {”Size”:”0.18,”Pos”:”0.01,0,0.01”,”Rot”:”-90,0,0”,”Up”:”5”}. What does “Up 5” mean?

I have the impression that when using the “Track Markers” component, only the position of the QR code is tracked and the content of the QR code is ignored. Is this assumption correct?

Is there a noticeable difference in accuracy between using ArUco markers and QR codes when they are the same size?

Thanks for the help


Hi @Lukas

The “Up” is an enumerable corresponding to an axis (X,Y,Z,-X,-Y,-Z). This is a hint to the device that the specified axis should be forced to be true up. For example, when you place a QR code on the ground, it will rarely be (or scan as) truly horizontal. Without the up vector being specified, any tiny deviation would mean the whole hologram would be undesirably rotated.

For Track Markers you are correct in that only the position is used. The content is to enable you to use different markers for different purposes in Grasshopper.

Aruco markers track faster (and perhaps ever so slightly more accurately) than QR codes and are hence more useful when a simple numeric code is enough information or size constraints are present (aruco codes contain less data, so can be made smaller than QR codes and still be recognised)

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