Spatial Operation for Geometry?

[Lei Jiang]

Is there any spatial operation for geometry? I only find "DoesContain" and
"DoesContainWithDetail".

Some other operations, such as "NearestNeighbor", "ContainsWhat", can't be
found. It seems Avalon have internally maintained a tree and the bounds of
chindren is cached, so it's very easy to implement a spatial index such as
r-tree.

[Krishna]

Thanks for the feedback !!

Avalon only supports DoesContain and DoesContainWithDetail operations
on Geometry as of now. Can you explain your scenario more
specifically? I will make sure we track this issue.

Thanks
Krishna

[Lei Jiang]

Thanks!

For example :

1. There are many object on the screen, and every object has to have a
label. These labels are positioned on the screen dynamically at runtime.
Certainly every label should not be overlapped with other labels. So for
each label, I'd like to know if it conflicts with other labels near the
object it annotates. This needs "NearestNeighbor" operations.

2. There are thousands of millions of object (each with coordinate of X, Y)
in memory and only part of them will be rendered to the screen. For a
specific window range, I'd like to render those visible to the window range.
I certainly don't want to iterate all objects to see if it's within the
window range. This needs "ContainsWhat" operations to get part of object
within the window range roughly and quickly and then only iterate these
selected object to test if it's in the window range.

These operations are common to applications such as CAD, GIS, etc. Of
course, it seems not very relevant to a OS graphics system. So it's a design
choice :P

"Krishna" <chy...@gmail.com> ????
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