Table of Contents:
In general, settings under these three section of the YafaRay UI are used to give specific YafaRay properties to meshes, light sources and cameras in the Blender 3D scene. The general workflow is:
With this feature, a whole mesh in the 3D scene can act as an area light source. The soft shadows produced by area lights need to be sampled several times and then interpolated to reduce noise. This type of light takes more time to render in contrast with point light types such as spot and point.
First of all, you must select the mesh you want it to act as a light source. Then you must enable Object data panel. Finally you must activate the Enable Meshlight button in the YafaRay Object Properties secion. To change the light color, just click on the rectangle next to Meshlight color to open a Color Picker.
Example of Meshlights, rendered with Bidirectional.
Other area light types:
Lights settings are now fully controlled by the YafaRay UI. The general workflow is creating or selecting a light in the 3D viewport and then editing its properties using the Lamp data section. Users can edit lamp type, color, power, shadows sampling, geometry, etc. It is worth rememberting that lighting power is in fact a product of a couple of settings, Color and Power, available for every light type.
In YafaRay there are two options to reproduce omnidirectional lighting which are Point and Sphere. A Point light is a typical omni directional point light source as in Blender Internal with hard shadows, while a Sphere light is a spherical area light source which can produce soft shadows.
The Sphere light settings are:
|Comparison between point light (left) and spherelight (right). Notice the different shadows.|
Other area light types:
In YafaRay there are two options to reproduce sun lighting which are Directional and Sun. Directional light is a traditional sun light model which produces parallel rays and hard-edged shadows.
Sun light is a more advanced concept and will help us to get blurred-edged shadows when the shadow itself gets away from the casting object, as in real life. The Angle button sets the visible area of the sun. Real sun is visible in a cone angle of about 0,5º. A bigger angle mean a bigger sun, as well as softer shadows, which could be interesting for dawn or sunset scenes. A very big angle can be used to simulate sun light filtered by an overcast sky.
|Comparison between Directional (left) and Sun (right). Notice how, with a Sun light, shadows get blurred as the distance with the casting object increases.|
Arealight is a area light type that can produce soft shadows and its shape can be seen in reflective surfaces. The arealight shadows need to be sampled several times and interpolated to reduce noise in shadows. This type of light takes more time to be computed in contrast with point light types such as spot and point.
Area light size can be controlled in the Area Shape section although you can scale lamp size in the 3D viewport as well. When Create and show geometry is enabled, a rectangle in the size of the area light is generated, so that the area light gets rendered in camera and on reflective components. More lighting power is added as well to the scene. When pathtracing is used, the Create and show geometry option also creates caustics paths, although there exist an option to not trace caustics paths with path tracing as they tend to be extremely noisy ('none' option in Pathtracing settings, see 5.1.1).
Example of a rectangular visible arealight.
Other area light types:
Spot is a common omnilight within a directional light beam. It has got a feature to blur shadows which could be useful when this light type is used as a sun light substitute in some photonmapping scenes.
In the bottom section of the spot light panel YafaRay developers have included Blender Internal spotlight geometry settings (Distance, Clip Start, Clip End, Show Cone) for more cues in beam directional control.
The general workflow is creating or selecting an existing camera in the 3D viewport and then editing its properties using the Camera data section. There are four camera types in YafaRay: Architect, Angular, Orthogonal and Perspective.
This camera type works like a Perspective camera type, the only difference is that the vertical component of the perspective effect is neglected, so scene vertical lines are not convergent. Depth of Field settings are available for this camera type as well. DOF settings are explained in the Perspective/DOF section.
|Comparison between Perspective (left) and Architect camera (right). Notice the lack of vertical convergence in the Architect camera. Scene by Kronos
Example of an angular camera, used to create perspective distortion. Scene by Gabich.
A camera type that renders an orthographic (perpendicular) projection of the scene, without perspective effects. Camera only setting is:
Comparison between perspective camera (left) and ortho camera (right).
Perspective is the standard camera mode that simulates a lenses photographic camera with perspective effects. All settings available for this camera type are used to enable and configure the depth of field (DOF) effect. The depth of field is the distance that objects appear in focus. DOF settings are:
The DOF effect depends also on the render anti aliasing settings to get a nice blurred effect. First of all it is recommended to lower AA threshold a bit, but not set it to totally zero. Setting a high number of AA passes is also not really going to make all that much difference, the main smoothness factor that makes the most difference is really the amount of AA samples. A single pass with a high number of samples may be sufficient.
Technically speaking, this feature shifts the image plane with respect to the focal point so the former is not longer centered. Useful for camera matching work.
Sets the camera clipping limits. Only objects within the limits are rendered. If Limits in the Display panel is enabled, the clip bounds will be visible as two yellow connected dots on the camera line of sight. Useful to make focal lengths compatible with scenes, as explained here,