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Hi everyone:<div><br></div><div>I'm a user of vtk. When I use vtkXYPlotActor to draw some lines at a XYPlot, I found vtk miss one line.</div><div>That's my sample code of vtkXYPlotActor:</div><div><span class="ecxApple-style-span" style="white-space:pre">=========================================================================
#include "vtkFloatArray.h"
#include "vtkFieldData.h"
#include "vtkDataObject.h"
#include "vtkXYPlotActor.h"
#include "vtkXYPlotWidget.h"
#include "vtkMath.h"
#include "vtkRenderWindow.h"
#include "vtkRenderer.h"
#include "vtkRenderWindowInteractor.h"
int main()
{
vtkFloatArray* vtkXYValues = vtkFloatArray::New();
vtkXYValues->SetNumberOfComponents( static_cast<vtkIdType>(2) );
float xy[2];
xy[0] = static_cast<float>(0);
xy[1] = static_cast<float>(0) ;
vtkXYValues->InsertNextTuple( xy );
xy[0] = static_cast<float>(2);
xy[1] = static_cast<float>(3) ;
vtkXYValues->InsertNextTuple( xy );
xy[0] = static_cast<float>(4);
xy[1] = static_cast<float>(15) ;
vtkXYValues->InsertNextTuple( xy );
xy[0] = static_cast<float>(6);
xy[1] = static_cast<float>(1) ;
vtkXYValues->InsertNextTuple( xy );
xy[0] = static_cast<float>(7);
xy[1] = static_cast<float>(0.1) ;
vtkXYValues->InsertNextTuple( xy );
xy[0] = static_cast<float>(8);
xy[1] = static_cast<float>(10) ;
vtkXYValues->InsertNextTuple( xy );
xy[0] = static_cast<float>(9);
xy[1] = static_cast<float>(9) ;
vtkXYValues->InsertNextTuple( xy );
xy[0] = static_cast<float>(10);
xy[1] = static_cast<float>(0) ;
vtkXYValues->InsertNextTuple( xy );
vtkFieldData* vtkGraphFieldData = vtkFieldData::New();
vtkGraphFieldData->AddArray( vtkXYValues );
vtkXYValues->Delete();
vtkDataObject* vtkGraphDataObject = vtkDataObject::New();
vtkGraphDataObject->SetFieldData( vtkGraphFieldData );
vtkGraphFieldData->Delete();
vtkXYPlotActor* vtkGraph = vtkXYPlotActor::New();
vtkGraph->AddDataObjectInput( vtkGraphDataObject );
vtkGraphDataObject->Delete();
vtkGraph->SetDataObjectPlotModeToColumns();
vtkGraph->SetXValuesToValue();
int curve = 0;
vtkGraph->SetDataObjectXComponent( curve, 0 );
vtkGraph->SetDataObjectYComponent( curve, 1 );
vtkGraph->SetXRange( 0, 10);
vtkGraph->SetYRange( 0, 8);
vtkGraph->SetPlotColor( curve, 1,0,0 );
vtkRenderer* renderer = vtkRenderer::New();
renderer->AddActor2D( vtkGraph );
vtkRenderWindow* renderWin = vtkRenderWindow::New();
renderWin->AddRenderer( renderer );
vtkRenderWindowInteractor* interactor =vtkRenderWindowInteractor::New();
interactor->SetRenderWindow( renderWin );
vtkXYPlotWidget* vtkXYPlotWidget = vtkXYPlotWidget::New();
vtkXYPlotWidget->SetXYPlotActor( vtkGraph );
vtkXYPlotWidget->SetInteractor( interactor );
vtkXYPlotWidget->SetEnabled( true );
interactor->Initialize();
interactor->Start();
return 0;
}
=========================================================================
I define eight points,<span lang="EN-US" style="font-size:10.5pt;font-family:Arial">a(0,0), b(2,3), c(4,15), d(6,1), e(7,0), f(8,10), g(9,9),h(10,0). And the range of xy axis is defined from point (0,0) </span></span></div><div><span class="ecxApple-style-span" style="white-space:pre"><span lang="EN-US" style="font-size:10.5pt;font-family:Arial">to (10,8). So there are three points(cfg) out of range. There should be six lines except the line fg which is out of range, but only five lines </span></span></div><div><span class="ecxApple-style-span" style="white-space:pre"><span lang="EN-US"></span>have been drawn. when I change these point to test, I found the line which the value of y axis is from 0(the min value of y axis) </span></div><div><span class="ecxApple-style-span" style="white-space:pre">to a value bigger than the max value of y axis will be ignored by vtk. </span></div><div><span class="ecxApple-style-span" style="white-space:pre"><br></span></div><span class="ecxApple-style-span" style="white-space:pre"> I guess the problem maybe happen when clipping data. So I debugged vtkXYPlotActor source, and I found the function </span><div><span class="ecxApple-style-span" style="white-space:pre">named ClipPlotData() have been called in the function CreatPlotData().</span><div><span class="ecxApple-style-span" style="white-space:pre"></span><span class="ecxApple-style-span" style="white-space:pre">The algorithm of clipping data is no problem. the number of lines which should be drawn is six.</span></div><div><span class="ecxApple-style-span" style="white-space:pre"><br></span></div><div><span class="ecxApple-style-span" style="white-space:pre">Cause I don't have enough time to do further research. If anyone has any information about this problem, please let me know.</span></div><div><span class="ecxApple-style-span" style="white-space:pre"><br></span></div><div><span class="ecxApple-style-span" style="white-space:pre">thanks.</span></div><div><span class="ecxApple-style-span" style="white-space:pre"><br></span></div><div><span class="ecxApple-style-span" style="white-space:pre">sincerely yours:</span></div><div><span class="ecxApple-style-span" style="white-space:pre">Elo</span></div><div><span class="ecxApple-style-span" style="white-space:pre"><br></span><div><br></div></div></div> <br><hr>搜索本应是彩色的,快来体验新一代搜索引擎-必应,精美图片每天换哦! <a href="http://cn.bing.com/?form=CRMADS ">立即试用！</a> <br /><hr />使用新一代 Windows Live Messenger 轻松交流和共享！ <a href='http://www.windowslive.cn/messenger/' target='_new'>立刻下载！</a></body>
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