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\page material_page Material

\n You can change the material properties of the selected shape(s) by
- choosing one of predefined global materials,
- choosing one of predefined user materials,
- creating a new user material and applying it to the selected shape(s)

in the following dialog box.

\image html material_front.png
<center><em><b>Set Material Properties</b> dialog: <b>Front material</b> tab</em></center>

\image html material_back.png
<center><em><b>Set Material Properties</b> dialog: <b>Back material</b> tab</em></center>

This functionality is available in both OCC and VTK viewers.

User can changed the following material properties

- ambient color and coefficient
- diffuse color and coefficient
- specular color and coefficient
- emission color and coefficient (available only in OCC viewer)
- shininess

With help of <b>Front material</b> and <b>Back material</b> tabs of
<b>Set Material Properties</b> dialog it is possible to set front and
back materials of the selected shape(s). To make <b>Back material</b>
tab visible it is needed to check <b>Enable back material</b> check
box. If back material is not defined, front material specified for the
selected shape(s) is used as both front and back materials.

All currently available materials are shown in the left-side list box
of the <b>Set Material Properties</b> dialog.

- <b>[Current]</b> item in the list corresponds to
  the front/back (depending on what tab is currently active) material
  currently used for the selected shape(s)
- <b>[Default]</b> item in the list corresponds to the front/back material
  specified in Geometry module preferences
- <b>Global</b> materials are shown in blue color in the list
- <b>User</b> materials are shown in black color in the list 


<b>Examples:</b>

\image html material_OCC.png
<center><em>Different materials in OCC viewer</em></center>

\image html material_VTK.png
<center><em>Different materials in VTK viewer</em></center>

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