bing maps how to get the not share square of 2 rectangle boundaries?

Question

I am using bing maps and I want to query my database to return all values inside the map bounds, so every time, the map moves, I want to query it again. In order to make it more efficient, I want to query only the boundary I haven't query before.

So I get the previous bound and the current bound and want to get the square bound of the non shared rectangle between the previous and the current rectangles (The not shared rectangle of the current bounds).

For example, If I move the map right for 5cm and up for 2cm, I will recieve a new LocationRect of the rectangle 5cm 2cm (the not shared).

I have the map bounds:

LocationRect currentBounds = map.Bounds;

When I move the map I get a new bounds, but before I save the previous bounds:

previousBounds = currentBounds;

I want to get the new location I moved to (only the new, not the whole currentBounds).

So I want to do something like this:

LocationRect newMapBounds = currentBounds.NotSharedBounds(previousBounds);

But how can I check this? I saw there is a method of Intersects but it returns bool, and I need to get the new LocationRect...

I will be very thankfull for the helper :)

Answer 1

If i understand you right you have the blue rectangle(ABCD) and when you move the map you have red rectangle(EHGF) and you know their vertexes coordinates e So the not common space creating 3 new rectangles for you: Green Yellow And Black.

And you need coordinates of those 3 rectangles in order to query your data, in other words you need to perform three queries to you DB in order to get the NOT common space of BLUE and RED rectangles.

You will have scenarios of RED and BLUE rectangles that you need to deal before you start the calculations:

1. The rectangles are coincide.

2. The scenario in the picture

3. They have no common space at all.

For example the vertexes coordinates of GREEN rectangle are(The second scenario):

T(x) = E(x), T(y) = D(y)

F is a common of RED and GREEN Rectangles

N(x) = B(x) , N(y) = G(y)

F is a common of BLUE and GREEN Rectangles

Hope it helps.