How to get the exact vector location of a loaded model

I am new to game developing and using the jMonkey engine. I started to develop an endless running type game. To run, I have created a map with blender and imported it to jME.

As the screenshot shows, I have added it to a terrain and made some mountains. Now I need to get the exact vector point of map (point A like point on screen shot).

This will help me to detect if the running object is on the map or not. Can some give me an answer or tell me the alternatives that experts use?

UPDATE

I want to detect whether the running object is on the silver color road or not. How can I do that?

Well your running object can be checked for location at anytime with someSpatial.getWorldTranslation()

as for telling whether it’s on the silver.

You can have the silver stuff be an actual spatial in the scene and check to see if the running object is colliding with it. Or use math to find what locations are on the silver spots.

Access the alpha map of the terrain that paints the road, scale your objects location to the size of the map and check the color of the map on the corresponding pixel.

Can you please describe more. I am absolute beginner for this subject.

@normen said: Access the alpha map of the terrain that paints the road, scale your objects location to the size of the map and check the color of the map on the corresponding pixel.

Sorry, he is not using a alpha map for painting the road.

@Plenker said: Sorry, he is not using a alpha map for painting the road.

Hello Peter!

Oh, hello Norman. Now I see, it was you, who giving a complete wrong hint to a beginner.

@Plenker said: Oh, hello Norman. Now I see, it was you, who giving a complete wrong hint to a beginner.

Yes, sometimes when relevant info is left out of a post we have to guess what the OP is actually doing. Since we don’t know anything about how the scene is constructed or what the road “is” then we have to guess that it’s like other terrain and there is a texture to lookup.

We really should just let the posts sit, though.

@Plenker said: Oh, hello Norman. Now I see, it was you, who giving a complete wrong hint to a beginner.

Hello Peter!

@pspeed said: Yes, sometimes when relevant info is left out of a post we have to guess what the OP is actually doing. Since we don't know anything about how the scene is constructed or what the road "is" then we have to guess that it's like other terrain and there is a texture to lookup.

We really should just let the posts sit, though.

I can’t answer the question, but I think it was clearly asked. There are three actors.

a) a Point (Location)
b) a Terrain
c) a Road

b) the terrain is not interesting, as I see it is generated by the SDK and ugly fits the Road.
c) the road is imported from blender. He wrote it in his question and you can see in the screenshot, that the road is an 3d-object.

I don’t know how you can get the idea of an alpha map … ask norman, he knows.

Solution:

I guess the road was imported as single object. You have to access the geometry (vertices/faces) and calculate on that, to find out if the point is “on top” of the map.

But, I would advise to think about the data structure of the map and go a different way.

If it’s just geometry then you could collide with a Ray pointing down to see if the object is over the road or not.