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## Real Lat/long coordinate system for Hotspots

Saturday, April 23rd 2011, 11:45pm

### Real Lat/long coordinate system for Hotspots

Hi everybody. I've been looking in the forum for ideas on how to tie the x,y,z atv, ath sphere system with the real lat/long/altitude coordinates. If for example I had my panorama geo-taged and wanted to have hotspots around using real coordinates and distances from the center of the sphere. Can any one think of ideas on how to do this? Maybe a conversion from Krpano coordinate system to lat/long system? Or the other way.

Will appreciate any help, thanks a lot.
360Media

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Friday, April 29th 2011, 11:51am

Have you seen this topic: Angle of panormaic images

Like I said in that post. A hotspot has atv/ath coordinates which are relative to the panoramic photo. You need to know 3 things about a panorama. the longtitude, the lattitude and the heading/bearing. A panorama is just a sphere with a texture/photo sticked to it. The texture does not make something be at North East or South West. You should make sure that ath=0 and atv = 0 match North in real world coordiantes.

then you could calculate the distance and the angle between panorama's. Once you know the angle, you have your ath. Atv is a bit different. You need to calculate the angle between two camera shoot heights +/- the height of the area where you are.

then you probally need to take in account the scale of an hotspot. You want more distant ones be smaller, then then closer ones. And you probally want to normalize that. The closest distance gets scale 1.0 and the most furthest hotspot in the panorama would take like 0.5. If you dont normalize, you could have scale 25.0 and 0.00001 for instance.

Creating such system would probally require a code language that can handle numbers well such as php, javascript or actionscript. Alsoo im not sure if distances between two points can be calculated easily, or that you need some sort of script that can translate gps coordinates to a metric system.

Alsoo x,y,z are screen coordinates, and can't be put in a lat/long system, unless you bind it to a panorama + atv/ath. For instance a button in your interface has x = 10 and y = 10. No matter where you are. But a hotspot that calls a gallery with images (and those images are on a x/y axis) could be bonded to a long/lat system (similar to google maps)

Saturday, April 30th 2011, 2:45pm

Thanks Zephyr, this is really helpful. Seems that it's about coding aggressively a conversion system that helps positioning a correct atv + scale. Your normalizing idea is correct. Thanks again, I will keep thinking on this conversion system and will let you know if I can create a good system for this.

Regards
Juan

Tuesday, May 3rd 2011, 6:02pm

I had been researching this very thing and everything that Zephyr said is spot on. I ended up ditching the idea because I saw some potential issues such as having hotspots placed too closely to each other. However, I did find that this website: http://www.movable-type.co.uk/scripts/latlong.html helped out a ton with understanding the calculations needed to accomplish this, they even have example code written in javascript.

Thursday, May 5th 2011, 12:02am

### Thank you Chrispen

Seems it will be an uphill battle..

Thanks
360Media