# How to draw perfectly uniform stipple lines

**URL:** https://discourse.vtk.org/t/how-to-draw-perfectly-uniform-stipple-lines/6750
**Category:** Support
**Created:** [October 1, 2021, 7:26pm UTC](https://discourse.vtk.org/t/how-to-draw-perfectly-uniform-stipple-lines/6750 "2021-10-01T19:26:55Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![Seun](https://discourse.vtk.org/user_avatar/discourse.vtk.org/seun/32/767_2.png) [@Seun](https://discourse.vtk.org/u/Seun)
#### Post date: [October 1, 2021, 7:26pm UTC](https://discourse.vtk.org/t/how-to-draw-perfectly-uniform-stipple-lines/6750/1 "2021-10-01T19:26:55Z")

</div>

Hello everyone,  
I was wondering if I could get some help with rendering stippled lines. I’m currently using a vtkActor attached to a PolyDataMapper of which I customise the Shader property in order to get the desired effect, however on closer inspection I notice that some part (ie: as can be seen in the attached images) the top part of the lines although stippled, seem to be connected in a jagged manner. I was expecting all lines to be uniformly rendered.  
Is there a better way of doing this? Thanks in advance.

 ![stipple](https://discourse.vtk.org/uploads/default/original/2X/6/6f20f313ddf252387a6011cd6c8a5cbbc15e7d08.png)

 ![001-top](https://discourse.vtk.org/uploads/default/original/2X/9/9b5ed4073ca168d51333f7c395b7c28ca9776c78.jpeg)  
 ![002-bottom](https://discourse.vtk.org/uploads/default/original/2X/6/65b76c3b6ebd98363c2ee9d985dd0bbec64a4c39.jpeg)

typically in code I just customise a vtkSmartPointer’s shader property (at the fragment level)

`inActor->GetShaderProperty()->AddFragmentShaderReplacement("//VTK::TCoord::Impl", true, shader, false);`