Operation Manual

transparent. If there is no view to the inside face, normally for an extruded 3D object
with solid texture, the Double-Sided should be switched off to improve performance
during rendering. Any 3D object created using rotation often allow an inside view and it
is recommended that Double-Sided is switched on. Which side of an object face is
considered to be back or front is determined by the Invert Normals setting, that is the
front side of a plane is the one the normal points away from.
3D Effects – Shading
On the Shading page of the Effects dialog (Figure 180) you can set the shading and shadow
options for the selected 3D object.
• Shading – specifies the type of shading applied to a 3D object (Figure 181).
– Flat Mode – assigns a single color of shading to a single segment on the surface of the
object.
– Gouraud Mode – blends shading colors across the segments.
– Phong Mode – averages the shading color of each pixel in a segment based on the
pixels that surround it, and requires the most processing power.
Figure 180: 3D Effects dialog - Shading
Figure 181: Shading mode examples
150 LibreOffice 4.3 Draw Guide