RenderOptions
 | RenderOptions | This node provides different settings to modify the rendering of objects. |
The RenderOptions node contains properties which are associated with the rendering process as a whole and are usually only set up once for a whole scene.
Culling
To reduce the load on the graphics card, triangles belonging to the part of a surface that does not face the camera can be rejected before they are rendered by the graphics card. The idea behind this is that if the vertex order is assigned consistently and all objects are modeled as solids (there is no hole that access the volume under the surface) or all non-solids are always correctly oriented towards the user, all back-face triangles will be overdrawn anyway. For more information, see Introduction to Realtime Rendering.
The decision whether to cull a triangle or not is done based on the order of vertices in a triangle when viewed from a user. Possible settings are:
- Inherit: The culling setting is inherited from a parent RenderOptions node. If there is none, Culling is set to the default value which is Clockwise.
- CounterClockwise: Polygon faces are culled if they have a counter-clockwise vertex order (seen from the position of the camera).
- Clockwise: Polygon faces are culled which have a clockwise vertex order .
- None: No culling takes places.
Fill Mode
The Fill Mode specifies the Rasterization behavior of a triangle once its vertices have been transformed to 2D screen space. By default, the graphics card will use the transformed vertices to construct the triangle in 2D space and generate fragments for all pixels occupied by the triangle. By changing the fill mode, Rasterization can be forced to only generate fragments for the boundary or even vertices only. This can for example be used to render a wireframe overlay over a solid geometry, showing the audience the tessellation of the object.
Possible settings are:
- Inherit: The setting is inherited from a parent RenderOptions node. If there is none, FillMode is set to the default value which is Solid.
- Solid: The geometry is rendered as a solid object. Fragments will be generated for the whole area of the triangle.
- Wireframe: Only the wireframe of the geometry, defined by the vertices, is rendered. Fragments will only be generated for the edges between vertices of a triangle, not the interior region.
- Point: At the position of every vertex a point is rendered. Use the Point Options node to adjust the render settings.
Color Write
The color write properties can be used to restrict rendering to specific color channels. For example, red channel can be disabled and whatever rendering is done underneath the Render Options node will not change the red components of any pixel in the render output.
Lines
AntiAlias can be used to explicitly activate or deactivate anti-aliasing of lines. This feature is dependent on the capabilities of the graphics card and will only have effect if the graphics card is capable of rendering anti-aliased lines.
The Property LastPixel specifies if the last pixel of a line should be rendered or not. This setting is useful in case of poly-lines where the endpoint of one line segment is the starting point of the next. This can lead to artifacts if the poly-line is transparent and the connection points are rendered twice.