>(renderData->GetTargetSphere(pos)[2], actor3));
}
```
---
### Author:  [@dgobbi](https://discourse.vtk.org/u/dgobbi)
#### Post date: [November 9, 2020, 2:38am UTC](https://discourse.vtk.org/t/are-the-coordinate-systems-of-sphere-and-polyline-different/4548/6 "2020-11-09T02:38:17Z")
The image as a little hard to see. Can you do a screen grab ([with the “Print Screen” button, for example](https://en.wikipedia.org/wiki/Print_Screen)) instead of taking a picture with your phone?
I don’t think it is a problem with the coordinate systems. The problem is the opacity. The line is hidden because it is inside the sphere, and this might be a bug.
In your original post, the blue line looked correct, but the red line looked wrong. What was the difference between how you drew the red line vs. the blue line?
---
### Author:  [@clolent](https://discourse.vtk.org/u/clolent)
#### Post date: [November 9, 2020, 3:04am UTC](https://discourse.vtk.org/t/are-the-coordinate-systems-of-sphere-and-polyline-different/4548/7 "2020-11-09T03:04:05Z")
Thank you for your kind attention.
Radius x 1 in the red center circle.
The outer circle has Radius x 1.3 and Radius x 2 respectively.
The blue line is twice as long as the red line. The coordinates are marked on the code.
```cpp
AddLine(_renderData, 0, 0, -50, 20, 0, -50, 255, 0, 0);
AddTarget(_renderData, 20 ,0, -50,5, 20, 20);
AddLine(_renderData, 0, 0, -50, -40, 0, -50, 0, 0, 255);
AddTarget(_renderData, -20, 0, -50, 5, 20, 20);
```
If you look at the blue line, it doesn’t look like the line is covered by the skin. So it’s even more confusing.
---
### Author:  [@dgobbi](https://discourse.vtk.org/u/dgobbi)
#### Post date: [November 9, 2020, 3:16am UTC](https://discourse.vtk.org/t/are-the-coordinate-systems-of-sphere-and-polyline-different/4548/8 "2020-11-09T03:16:42Z")
I see. It’s as if only half of the line is drawn. What happens if you do not stipple the line? Maybe the stipple is causing problems with the rendering.
---
### Author:  [@clolent](https://discourse.vtk.org/u/clolent)
#### Post date: [November 9, 2020, 3:20am UTC](https://discourse.vtk.org/t/are-the-coordinate-systems-of-sphere-and-polyline-different/4548/9 "2020-11-09T03:20:17Z")
I’m glad you understood. Thank you.
The other parts are all the same and only the stipple sections are annotated.
The length of the line does not seem to change.
---
### Author:  [@dgobbi](https://discourse.vtk.org/u/dgobbi)
#### Post date: [November 9, 2020, 3:24am UTC](https://discourse.vtk.org/t/are-the-coordinate-systems-of-sphere-and-polyline-different/4548/10 "2020-11-09T03:24:35Z")
As a test, try converting the polyline into a polygonal tube with [vtkTubeFilter](https://lorensen.github.io/VTKExamples/site/Cxx/PolyData/TubeFilter/). If the problem disappears with vtkTubeFilter, then it is definitely a problem with rendering lines.
---
### Author:  [@clolent](https://discourse.vtk.org/u/clolent)
#### Post date: [November 9, 2020, 3:26am UTC](https://discourse.vtk.org/t/are-the-coordinate-systems-of-sphere-and-polyline-different/4548/11 "2020-11-09T03:26:52Z")
Okay, I’ll test it right away. Thank you.
---
### Author:  [@clolent](https://discourse.vtk.org/u/clolent)
#### Post date: [November 9, 2020, 3:40am UTC](https://discourse.vtk.org/t/are-the-coordinate-systems-of-sphere-and-polyline-different/4548/12 "2020-11-09T03:40:00Z")
Unfortunately, there seems to be no difference in length.
---
### Author:  [@dgobbi](https://discourse.vtk.org/u/dgobbi)
#### Post date: [November 9, 2020, 3:45am UTC](https://discourse.vtk.org/t/are-the-coordinate-systems-of-sphere-and-polyline-different/4548/13 "2020-11-09T03:45:19Z")
That doesn’t look like the output of vtkTubeFilter. Please make sure the output from vtkTubeFilter goes into the mapper.
---
### Author:  [@clolent](https://discourse.vtk.org/u/clolent)
#### Post date: [November 9, 2020, 6:17am UTC](https://discourse.vtk.org/t/are-the-coordinate-systems-of-sphere-and-polyline-different/4548/14 "2020-11-09T06:17:18Z")
I did what you said. But the problem that happened doesn’t seem to have been solved.
---
### Author:  [@clolent](https://discourse.vtk.org/u/clolent)
#### Post date: [November 9, 2020, 6:21am UTC](https://discourse.vtk.org/t/are-the-coordinate-systems-of-sphere-and-polyline-different/4548/15 "2020-11-09T06:21:55Z")
 Look at this.
In the existing code, Line and Sphere were created by putting them all in a function, not separately.
That’s how the picture was drawn, as intended. But I still don’t know why this is happening.
```cpp
AddLine(_renderData, 0, 0, -50, 10, 0, -50, 255, 0, 0);
void RenderBox::AddLine(std::shared_ptr renderData, double startX, double startY, double startZ, double vectorX, double vectorY, double vectorZ, int r, int g, int b)
{
// Target Sphere
vtkSmartPointer sphereSource = vtkSmartPointer::New();
sphereSource->SetCenter(startX, startY, startZ);
sphereSource->SetRadius(5);
sphereSource->SetPhiResolution(40);
sphereSource->SetThetaResolution(20);
// Mapper
vtkSmartPointer polyDataMapper0 = vtkSmartPointer::New();
polyDataMapper0->SetInputConnection(sphereSource->GetOutputPort());
vtkSmartPointer actor0 = vtkSmartPointer::New();
actor0->SetMapper(polyDataMapper0);
actor0->SetPosition(0, 0, 0);
actor0->GetProperty()->SetOpacity(0.3);
actor0->GetProperty()->SetColor(1.0, 0, 0);
actor0->GetProperty()->BackfaceCullingOn();
_modelRenderer->AddActor(actor0);
// Target Sphere End
// Inner Sphere
vtkSmartPointer sphereSource2 = vtkSmartPointer::New();
sphereSource2->SetCenter(startX, startY, startZ);
sphereSource2->SetRadius(5 * 1.3);
sphereSource2->SetPhiResolution(40);
sphereSource2->SetThetaResolution(20);
// Mapper
vtkSmartPointer polyDataMapper2 = vtkSmartPointer::New();
polyDataMapper2->SetInputConnection(sphereSource2->GetOutputPort());
vtkSmartPointer actor2 = vtkSmartPointer::New();
actor2->SetMapper(polyDataMapper2);
actor2->SetPosition(0,0,0);
actor2->GetProperty()->SetOpacity(0.2);
actor2->GetProperty()->BackfaceCullingOn();
_modelRenderer->AddActor(actor2);
// Inner Sphere End
// Outter Sphere
vtkSmartPointer sphereSource3 = vtkSmartPointer::New();
sphereSource3->SetCenter(startX, startY, startZ);
sphereSource3->SetRadius(5 * 2.0);
sphereSource3->SetPhiResolution(40);
sphereSource3->SetThetaResolution(20);
vtkSmartPointer polyDataMapper3 = vtkSmartPointer::New();
polyDataMapper3->SetInputConnection(sphereSource3->GetOutputPort());
vtkSmartPointer actor3 = vtkSmartPointer::New();
actor3->SetPosition(0,0,0);
actor3->SetMapper(polyDataMapper3);
actor3->GetProperty()->SetOpacity(0.1);
actor3->GetProperty()->BackfaceCullingOn();
_modelRenderer->AddActor(actor3);
// Outter Sphere End
std::array pos = { startX ,startY,startZ };
renderData->AddTargetSphere(pos, 5);
_modelDataBindInfoVector.emplace_back(std::pair, vtkSmartPointer>(renderData->GetTargetSphere(pos)[0], actor0));
_modelDataBindInfoVector.emplace_back(std::pair, vtkSmartPointer>(renderData->GetTargetSphere(pos)[1], actor2));
_modelDataBindInfoVector.emplace_back(std::pair, vtkSmartPointer>(renderData->GetTargetSphere(pos)[2], actor3));
double origin[3] = { startX, startY, startZ };
double p0[3] = { vectorX, vectorY, vectorZ };
vtkSmartPointer points = vtkSmartPointer::New();
points->InsertNextPoint(origin);
points->InsertNextPoint(p0);
vtkSmartPointer polyLine = vtkSmartPointer::New();
polyLine->GetPointIds()->SetNumberOfIds(2);
for (unsigned int i = 0; i < 2; i++)
polyLine->GetPointIds()->SetId(i, i);
vtkSmartPointer cells = vtkSmartPointer::New();
cells->InsertNextCell(polyLine);
vtkSmartPointer polyData = vtkSmartPointer::New();
polyData->SetPoints(points);
polyData->SetLines(cells);
vtkSmartPointer polyDataMapper = vtkSmartPointer::New();
polyDataMapper->SetInputData(polyData);
vtkSmartPointer actor = vtkSmartPointer::New();
actor->SetMapper(polyDataMapper);
actor->GetProperty()->SetColor(r, g, b);
actor->GetProperty()->SetLineWidth(2);
actor->SetPosition(0, 0, 0);
// SetStippledLineTexture(actor, 0xAAAA, 1);
_modelRenderer->AddActor(actor);
renderData->AddLine(startX, startY, startZ, vectorX, vectorY, vectorZ);
_modelDataBindInfoVector.emplace_back(std::pair, vtkSmartPointer>(renderData->GetLine(startX, startY, startZ, vectorX, vectorY, vectorZ), actor));
}
```
