How to use alignedAxis for a billboard

CesiumJS
1

Hello

I trying to use alignedAxis to control orientation for a billboard image in CZM. Unfortunately impossible to understand how it works
Let say rather than having my billboard facing to the viewer, I would like to have it facing to the up direction
It is someting to be done like this?

“alignedAxis”: { “cartesian”: [1, 0, 0] }

when doing like this, I can see not real differences with the default orientation for billboard. Perhaps just the billboard marker having rotated around its Z axes but always facing the viewer

Hope you will be able to help

thanks

2

Have you seen the code examples for alignedAxis the Cesium API? alignedAxis is defined in world WGS84 coordinates.

     // Have the billboard up vector point north

billboard.alignedAxis = Cesium.Cartesian3.UNIT_Z;

// Have the billboard point east

billboard.alignedAxis = Cartesian3.UNIT_Z;

billboard.rotation = -Cesium.Math.PI_OVER_TWO;

     // Reset the aligned axis

billboard.alignedAxis = Cesium.Cartesian3.ZERO;

Patrick

3

HI PAtrick

Will have a look

Since I need to do this in a CZML file will trying to make it working

I want for an aircraft marker, having the billboard parallel to the earth surface at the lat/lon positon for my aircraft

I am using something like this but always align to the viewer!!! The viewer is probably not living in the WSG84 world :slight_smile:

billboard.alignedAxis.cartesian.Add(Math.Cos(myAC.lon * Math.PI / 180.0));

billboard.alignedAxis.cartesian.Add(Math.Sin(myAC.lon * Math.PI / 180.0));

billboard.alignedAxis.cartesian.Add(Math.Sin(myAC.lat * Math.PI / 180.0));

4

Ah, perhaps you want a rectangle primitive with an image material.

Patrick