# Texture mapping on a polygon

**URL:** https://discourse.vtk.org/t/texture-mapping-on-a-polygon/15558
**Category:** Support
**Created:** [April 29, 2025, 5:50pm UTC](https://discourse.vtk.org/t/texture-mapping-on-a-polygon/15558 "2025-04-29T17:50:22Z")
**Posts on this page:** 1
**Showing post:** 2

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### Author: ![jaswantp](https://discourse.vtk.org/user_avatar/discourse.vtk.org/jaswantp/32/10046_2.png) [@jaswantp](https://discourse.vtk.org/u/jaswantp)
#### Post date: [April 29, 2025, 6:09pm UTC](https://discourse.vtk.org/t/texture-mapping-on-a-polygon/15558/2 "2025-04-29T18:09:35Z")

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Looks like the colors are getting interpolated after being mapped which makes the result show the polygon’s underlying triangulation, you can identify this with the long edge joining (-2, -0.5) and (0, 0).

Can you try interpolating before mapping? Call `m_polyDataMapper->SetInterpolateScalarsBeforeMapping(true);`

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_[View the full topic](https://discourse.vtk.org/t/texture-mapping-on-a-polygon/15558)._