Thanks for your insights and help.
The lines I'm working with will have multiple points. They are
hurricane tracks. The tracks are made of points, about 3-12 hours
apart. Therefore, sometimes the points are close and other times very
far away from each other. I can easily connect the track points to
create a line. But I need the points in between each observation so
that I can determine what county landfall occurs. The y=mx+b method
will work, but I was hoping there may be an easier to do it. Or perhaps
I'm making the problem too complicated to begin with??
Mark
Bob Basques wrote:
All,
If you don't care about the actual coordinates of the points along the
line (just trying to display things) I wonder if a linetype/combined
with a scaling option would get you what you are looking for.
bobb
>>> Andy Colson <[email protected]> wrote:
On 4/15/2010 10:51 AM, Mark Brooks wrote:
> I'm using PHP Mapscript. I need a point every X meters along the line.
>
> Mark
>
>
> Andy Colson wrote:
>> On 4/15/2010 10:24 AM, Mark Brooks wrote:
>>> I have a line object that I need to to turn into points. How can I
>>> create a series of points from the line object?
>>>
>>> Mark
>>> NC State University
>>
>> A line has many many points. Which are you interested in? Just the
>> first and last? Any one point on the line? The mid-point? A point
>> every meter along the line? The closes point on the line to some other
>> object?
>>
>> I know of two options:
>> 1) use PostGIS:
>> select st_centroid(the_geom) from layer
>>
>> 2) use mapscript
>>
>>
>> -Andy
>
Does the line have a single start and end point? (a MULTILINE record
can have multiple lines (so multiple start and end points, all stuck
togethor).
In general, find the start and end points, use them to find the equation
of the line (y=mx+b if I recall correctly), then use that equation to
find one corrd based on another. (so, plug in a buch of x's to find
their y's).
-Andy
_______________________________________________
mapserver-users mailing list
[email protected]
http://lists.osgeo.org/mailman/listinfo/mapserver-users
