[vtkusers] vtkSpline

[Ho Ngoc Ha]

Hi, I picked another set of points and here are the results. Thanks a lot!

t: 0
x: 519.751, y:  1513.14, z: 0

t: 0.473684
x: 519.726, y:  1500.95, z: 0

t: 0.947368
x: 519.741, y:  1475.55, z: 0

t: 1.42105
x: 519.87, y:  1452.08, z: 0

t: 1.89474
x: 519.826, y:  1436.93, z: 0

t: 2.36842
x: 519.203, y:  1430.78, z: 0

t: 2.84211
x: 517.644, y:  1413.63, z: 0

t: 3.31579
x: 515.1, y:  1358.18, z: 0

t: 3.78947
x: 514.835, y:  1267.1, z: 0

t: 4.26316
x: 521.848, y:  1162.43, z: 0

t: 4.73684
x: 534.034, y:  1066.13, z: 0

t: 5.21053
x: 543.353, y:  999.33, z: 0

t: 5.68421
x: 548.978, y:  967.812, z: 0

t: 6.15789
x: 558.516, y:  959.351, z: 0

t: 6.63158
x: 572.076, y:  943.877, z: 0

t: 7.10526
x: 577.448, y:  865.487, z: 0

t: 7.57895
x: 568.835, y:  714.475, z: 0

t: 8.05263
x: 556.11, y:  582.674, z: 0

t: 8.52632
x: 548.223, y:  536.911, z: 0

t: 9
x: 545.789, y:  535.286, z: 0

--- On Sat, 9/5/09, Bill Lorensen <bill.lorensen at gmail.com> wrote:

From: Bill Lorensen <bill.lorensen at gmail.com>
Subject: Re: [vtkusers] vtkSpline
To: "Ho Ngoc Ha" <ha_lennon at yahoo.com>
Cc: vtkusers at vtk.org
Date: Saturday, September 5, 2009, 11:52 PM

Please print:
std::cout << "x: " << aSplineX->Evaluate(t) << ", y:  " <<
aSplineY->Evaluate(t) << ", z: " << aSplineZ->Evaluate(t) <<
std::endl;


On Sat, Sep 5, 2009 at 12:03 PM, Ho Ngoc Ha<ha_lennon at yahoo.com> wrote:
> Hi, these are the result
> t: 0
> t: 0.42105
> t: 0.84210
> t: 1.26316
> t: 1.68421
> t: 2.10526
> t: 2.52632
> t: 2.94737
> t: 3.36842
> t: 3.78947
> t: 4.21053
> t: 4.63158
> t: 5.05263
> t: 5.47368
> t: 5.89474
> t: 6.31579
> t: 6.73684
> t: 7.15789
> t: 7.57895
> t: 8
>
> i don't know what's wrong with it. Please help me :(
>
> --- On Sat, 9/5/09, Bill Lorensen <bill.lorensen at gmail.com> wrote:
>
> From: Bill Lorensen <bill.lorensen at gmail.com>
> Subject: Re: [vtkusers] vtkSpline
> To: "Ho Ngoc Ha" <ha_lennon at yahoo.com>
> Cc: vtkusers at vtk.org
> Date: Saturday, September 5, 2009, 7:17 PM
>
> Your code look OK. What is the resulting output of the std::cout <<
> "t: " << t << std::endl;
>
> Bill
>
> On Sat, Sep 5, 2009 at 1:45 AM, Ho Ngoc Ha<ha_lennon at yahoo.com> wrote:
>> Hi,
>>
>> I have a set of points, I just need to find a spline that pass through all
>> of those points and generate a number of output points.
>>
>> Here is what I did
>>
>> int numberOfInputPoints = points->GetNumberOfPoints();
>>
>>     vtkCardinalSpline* aSplineX;
>>     vtkCardinalSpline* aSplineY;
>>     vtkCardinalSpline* aSplineZ;
>>
>>     aSplineX = vtkCardinalSpline::New();
>>     aSplineY = vtkCardinalSpline::New();
>>     aSplineZ = vtkCardinalSpline::New();
>>
>>     for (int i=0; i<numberOfInputPoints; i++)
>>     {
>>       double x = points->GetPoint(i)[0];
>>       double y = points->GetPoint(i)[1];
>>       double z = points->GetPoint(i)[2];
>>           aSplineX->AddPoint(i, x);
>>           aSplineY->AddPoint(i, y);
>>           aSplineZ->AddPoint(i, z);
>>
>>     }
>>
>>     vtkPoints* polypoints = vtkPoints::New();
>>
>>
>>     int numberOfOutputPoints = 20;
>>
>>        double t;
>>        for (int i=0; i<numberOfOutputPoints; i++)
>>     {
>>       t
>>
>> =(double)(numberOfInputPoints-1)/(double)(numberOfOutputPoints-1)*(double)i;
>>       std::cout << "t: " << t << std::endl;
>>       polypoints->InsertNextPoint(aSplineX->Evaluate(t),
>> aSplineY->Evaluate(t),
>>                        aSplineZ->Evaluate(t));
>>     }
>>
>>
>> I thought the newly generated points will be stored in polypoints? But
>> when
>> I checked it, it only contains the first and the last point of my input
>> points.
>>
>> I am new to vtk so please help me. Thank you very much
>>
>> _______________________________________________
>> Powered by www.kitware.com
>>
>> Visit other Kitware open-source projects at
>> http://www.kitware.com/opensource/opensource.html
>>
>> Please keep messages on-topic and check the VTK FAQ at:
>> http://www.vtk.org/Wiki/VTK_FAQ
>>
>> Follow this link to subscribe/unsubscribe:
>> http://www.vtk.org/mailman/listinfo/vtkusers
>>
>>
>
>



      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.vtk.org/pipermail/vtkusers/attachments/20090905/04ebe574/attachment.htm>