Window Light
1. General Description
Window Light is a solution to simulate the diffuse light in the rooms which is generated by the incoming sunlight.
The final intensity of the light depends on the following values:
- the size of the window
- the angle between the sun azimuth and the direction of the window
- the intensity given by the user
The following pictures show the rendering output without and with Window Lights set.
2. Parameters
The input parameters of this object are:
| Hide | Name | Type | Default | Effects | Description |
|---|---|---|---|---|---|
| A | Length | 1 | 2D / 3D | Width of the window | |
| B | Length | 1 | 3D | Height of the window | |
| C | Boolean | 1 | 3D | Switch the light source on / off | |
| D | RGB | 0.7333 | 3D | Red color component | |
| E | RGB | 0.8235 | 3D | Green color component | |
| F | RGB | 1.0 | 3D | Blue color component | |
| G | Intensity | 50 | 3D | Intensity of the Window Light | |
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ZZYZX | Length | 1 | - | Not used |
|
AC_show2DHotspotsIn3D | Boolean | 0 | - | Not used |
| gs_lwa_light_res | Integer | 0 | 3D | The number of light sources. Available values: 0 - 5 | |
| gs_lwa_cast_shadows | Boolean | 1 | 3D | Shadows casting on/off | |
| gs_lwa_soft_shadows | Boolean | 1 | 3D | Shadow softness on/off | |
| gs_lwa_shadow_quality | Integer | 3 | 3D | Quality of shadows. Available values: 0 - 5 | |
| gs_lwa_rotateangle | Angle | 0 | 2D / 3D | Rotation angle around the X axle. It can be used for skylights in roofs. Available values: [-90; 90] | |
| gs_lwa_set_sun_position | Boolean | 0 | 2D / 3D | Set Sun Position Manually | |
| gs_lwa_sun_azimuth | Angle | 0 | 2D / 3D | Sun Azimuth - If gs_lwa_set_sun_position = 0 then this parameter use the GLOB_SUN_AZIMUTH global. | |
| 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. | |
| gs_cont_pen | Pen | 10 | 2D / 3D | Object contour pen | |
|
gs_lwa_intensity | Length | 0.5 | 2D / 3D | Internal parameter for the hotspot editing of the Intesity |
|
gs_lwa_halfwidth | Length | 0.5 | 2D / 3D | Internal parameter for the hotspot editing of the window width |
|
gs_lwa_projected_height | Length | 1.0 | 2D | Internal parameter for the hotspot editing of the window height in case of gs_lwa_rotateangle <> 0 |
Light Resolution
This parameter is used to specify the number of light sources generated in the area of the window.
Available values are:
| 0 | Only one light source is generated in the middle of the window |
| 1 - 5 | One or more light sources are generated depending on the surface of the window and the intensity of light |
It is worthwhile to set this parameter at least to 1 if the side ratio of the window exceeds 1:2.
For larger window sizes (eg. surface greather than 5 m²) it is worthwhile to set it to 2 or higher.
Note that using larger values can decrease the amount of overexposed areas.
| gs_lwa_light_res = 0 | gs_lwa_light_res = 1 |
|---|---|
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Shadow Casting
This parameter sets shadow casting of the Window Light on / off.
| gs_lwa_cast_shadows = 0 | gs_lwa_cast_shadows = 1 |
|---|---|
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Soft and Hard Shadows
This parameter is used to specify whether hard-edged shadows or soft-edged shadows should be created.
| gs_lwa_soft_shadows = 0 | gs_lwa_soft_shadows = 1 |
|---|---|
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Shadow Quality
It defines the quality of the soft shadows casted by the Window Light.
Available values are integer numbers with the range [0 - 5]. The default is 3.
It maps the following LightWorks® shader arguments:
- LWA_LIgsspot_shadowresol - it is mapped to the range 128 - 4096 exponentially
- LWA_LIgsspot_shadowquality - it is mapped to the range 4 - 9 linearly
| gs_lwa_shadow_quality = 1 | gs_lwa_shadow_quality = 3 |
|---|---|
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3. Usage
- Place the light in front of the window's glass and rotate it to face inwards. The direction of the light is represented by an arrow both in 2D and 3D.
- Set up the "Width of the Window" and the "Height of the Window" parameters according to the related window. You can do it with 2D/3D hotspot editing too.
- The light intensity will be calculated by the object from these input parameters but you can modify it manually with the lamp intensity parameter. It is 50% by default. You can also adjust it with 2D/3D hotspot editing.
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