On Tue, 2 Jul 2002 12:53:03 -0400, "Neil Talsania"
<neil.talsania@kodak.com> wrote:
> I am relatively new to IDL , and am wondering how to do the following. I
> want to be able to have user input 4 corner coordiates, then check to see if
> a particular point is inside the rectangle. That is pretty easy, i think.
> But then I want to be able to add additional sets of coordinates to check. I
> want this to be unlimited. Basically allowing the user to add rectangles to
> check until he is ready to stop.
Hello,
This came up a while ago in regards to Delauney triangulation
meshes... but what's a triangle but a pointy headed rectangle. The
following might help. You should note that you will need David
Fanning's LoadData function and Liam Gumley's ImDisp procedure. Also,
you might want to rename the object... I wasn't very original when I
named it.
Once you have all the code do the following from the command line...
IDL> .compile anroigroup__define
IDL> example
I hope this helps.
Ben
;--------START
;------
; WhichROI
;------
FUNCTION AnROIGroup::WhichROI, X, Y, Z, $
count = count, type = type, index = index
;This function returns the IDLanROI (OR the ROIs)
;that contain the point X,Y,Z Only one point is tested
;per call. If more than ROI contains the point, then
;an array of IDLanROI objects is returned
;
;X,Y,Z see IDLanROI::ContainsPoints
; ONLY a single point checked
;COUNT the number of ROIs found that contain X, Y, Z
;TYPE an array of the values returned by the
; IDLanROI::ContainsPoints method
;INDEX the postional index of the IDLanROI
; within the AnROIGroup
np = n_params()
Case np of
1: data = x[0:2]
2: data = [x[0], y[0]]
3: data = [X[0],Y[0], Z[0]]
EndCase
For i = 0L, self->Count() -1 DO Begin
ROI = Self->Get(Position = i)
r = ROI->ContainsPoints(data)
If r GT 0 Then Begin
If n_elements(Arr) EQ 0 Then Begin
Arr = ROI
type = r
Index = i
EndIf Else Begin
Arr = [Arr,ROI]
type = [type,r]
Index = [index,i]
EndElse
EndIf
EndFor
Count = n_elements(Arr)
Return,Arr
END ;WhichROI
;------
; Definition
;-------
PRO AnROIGroup__Define
struct = {AnROIGroup, $
Inherits IDLanROIGroup}
END ;AnROIGroup
;--------
; EXAMPLE
;--------
PRO Example
bottom = 32
loadCT, 0,bottom = bottom
Tek_Color
XYZ = LoadData(14)
Triangulate, XYZ[0,*],XYZ[1,*], tri
Surf = TriGrid( XYZ[0,*],XYZ[1,*],XYZ[2,*], tri,$
xgrid = xg, ygrid = yg)
xRange = [Min(xg), Max(xg)]
yRange = [Min(yg), Max(yg)]
ImDisp, Surf, /axis,/erase, xrange = xrange, $
yrange = yrange, bottom = bottom, $
Color = 1, Background = 0
oPlot, XYZ[0,*],XYZ[1,*], psym = 6, color = 2
Group = OBJ_NEW('AnROIGroup')
For i = 0, n_elements(Tri)/3 -1 Do Begin
index = [tri[*,i], tri[0,i]]
oPlot, XYZ[0,index],XYZ[1,index], color = 3
o = OBJ_NEW('IDLanROI', XYZ[0,index],XYZ[1,index])
Group->Add, o
EndFor
myX = [-110.0]
myY = [29.0]
PlotS, myX, myY, psym = 2, color = 4
Arr = Group->WhichROI(myX, myY, $
count = count, type = type, index = index)
If Count GT 0 Then Begin
Help, arr
print, count
print, type
print, index
Arr[0] ->GetProperty, Data = Data
oPlot, Data[0,*], Data[1,*], thick = 2, color = 5
EndIf
Obj_Destroy, Group
END
;---------END
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