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
	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:

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

Shadow Casting

This parameter sets shadow casting of the Window Light on / off.

gs_lwa_cast_shadows = 0	gs_lwa_cast_shadows = 1

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

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

3. Usage

1. 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.
2. 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.
3. 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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