Sky Object
1. General Description
Sky Object is used to simulate the diffuse light effect of the sky for photorendering. It consists of distant lights distributed in a hemispherical array.
The object has two working modes: 'Quick Method' and 'Realistic Method'. In the 'Quick Method', the object places LWA_LIdistant light sources (see original documentation and parameter mapping) distributed in a hemisphere. In 'Realistic Method' only one LWA_LIgssky light source is placed.
2. Parameters
The input parameters of this object are:
| Name | Type | Default | Affects | Description |
|---|---|---|---|---|
| A | Length | 1 | 2D / 3D | Not used |
| B | Length | 1 | 3D | Not used |
| C | Boolean | 1 | 3D | Switch on / off the light source |
| D | RGB | 0.81 | 3D | Red colour component |
| E | RGB | 0.89 | 3D | Green colour component |
| F | RGB | 0.99 | 3D | Blue colour component |
| G | Intensity | 50 | 3D | Intensity of the Sky Light |
| ZZYZX | Length | 1 | - | Not used |
| AC_show2DHotspotsIn3D | Boolean | 0 | - | Not used |
| gs_sky_type | String | "Quick Method" | 3D | Rendering type: 'Quick Method' / 'Realistic Method' |
| gs_lwa_lattitude_res | Integer | 3 | 3D | The number of latitudinal lines used in placing light sources in 'Quick Method'. Available values: >=1 |
| gs_lwa_longitude_res | Integer | 6 | 3D | The number of longitudinal lines used in placing light sources in 'Quick Method'. Available values: >=3 |
| gs_lwa_num_lights | Integer | 11 | - | Informs the user from the number of generated light sources in 'Quick Method'. |
| gs_lwa_cast_shadows | Boolean | 1 | 3D | Shadow casting on / off. |
| gs_lwa_soft_shadows | Boolean | 1 | 3D | Shadow softness on / off. Affects 'Quick Method' only. |
| gs_lwa_shadow_quality | Integer | 2 | 3D | Quality of the shadows. Available values: 0 - 5. Affects 'Quick Method' only. |
| gs_lwa_set_sun_position | Boolean | 0 | 2D / 3D | Set Sun Position Manually. Affects 'Quick Method' only. |
| gs_lwa_sun_azimuth | Angle | 0 | 2D / 3D | Sun Azimuth - If gs_lwa_set_sun_position = 0 then this parameter uses the GLOB_SUN_AZIMUTH global. Affects 'Quick Method' only. |
| gs_lwa_sun_altitude | Angle | -1 | 3D | Sun Altitude - If gs_lwa_set_sun_position = 0 then this parameter use the GLOB_SUN_ALTITUDE global. Affects 'Quick Method' only. |
| gs_numSamples | Integer | 50 | 3D | Number of samples - used in 'Realistic Method'. |
| gs_cont_pen | Pen | 10 | 2D / 3D | Object contour pen |
Longitudinal and Latitudinal Resolution
Longitude and latitude resolution parameters are used to specify the number
of the generated light sources to represent the sky.
Latitude resolution equals the number of latitudinal lines on the hemisphere.
Number of longitudinal lines is measured on the first latitudinal line (the nearest to the equator).
The number of longitudes (eg. light sources) along the rest of the latitudinal lines
is decreased to guarantee the equal light distribution.
Soft and Hard Shadows
This parameter is used to specify whether hard-edged shadows or soft-edged shadows are created. Effective if gs_lwa_cast_shadows is on.
Shadow Quality
The parameter defines the quality of the soft shadows cast by the sky. Available values are integer numbers in the range [0 - 5]. The default is 2. It maps the following LightWorks® shader arguments:
- LWA_LIdistant_shadowresol - it is mapped to the range 128 - 4096 exponentially
- LWA_LIdistant_shadowquality - it is mapped to the range 4 - 9 linearly
3. Usage
Place the Sky Object just anywhere in the plan.
Note, that the integrated LightWorks® rendering doesn't give a proper image quality in case the 3D data stucture is generated from a selection (e.g. with the Arrow Tool or with the Marque Tool) and this selection doesn't contain the Sky Object.
The LightWorks ® API is copyright (C) 1999,2000-2004 LightWork ® Design Ltd. All Rights Reserved.
