Light Sources Parameters

Toggles rendering of shadows from the light source on and off.

Is available when the Static light mode is enabled. Two shadow modes are available:

• Mixed. Shadows from surfaces with both static and dynamic shadow mode are rendered as follows: the dynamic shadow map is merged with the static depth texture and the result is rendered.
• Static. Only shadows from surfaces with the static shadow mode enabled are rendered. These shadows are stored in the depth texture.

For fine-tuning static light and shadows, see the optimization recommendations.

Size of the shadow map that defines the shadow quality.

• The higher the resolution, the smoother and true to life the result is.
• The lower the resolution, the more blocky and jagged the shadow outline appears.

Shadow resolution = 64	Shadow resolution = 512

Shadow bias that is used to correct inexact shadowing of the scene objects. It controls the depth offset added to the current depth value stored in the shadow map. Such offset is adaptively calculated taking into account the slope angle of the light source, its resolution, and the distance to the light source at shadow map application.

• If the shadow acne appears, the bias value should be increased. This procedure eliminates the self-shadowing effect, as the points will appear closer to light source when compared to the map depth value.
• If the bias value is set too high, the shadow will look detached from the object casting it (see the 3rd picture below).

Bias = 0; Normal bias = 1

Bias = 4; Normal bias = 1

Bias = 30; Normal bias = 1

Shadow bias that is achieved by shifting the surface on which the shadow falls. The surface is shifted along normals stored in the normal map.

Normal bias = 0; Bias = 1	Normal bias = 2; Bias = 1

Depending on the normal map of the surface, the shadow may differ for the same values of Normal Bias.

Normal bias = 2	Normal bias = 2

Filtering mode to be used to reduce the stair-step effect for soft shadows making the edges smoother.

• Global — filtering mode selected globally in the Settings window is to be used for shadows.
• Disabled — filtering for shadows is disabled, the stair-step effect is clearly seen at the edges of shadows.
• Low, Medium, High, Ultra — filtering quality modes from the lightest to the heaviest one, which best reduces the stair-step effect but has a more significant impact on performance.

Quality mode to be used for penumbra rendering. This mode enables simulation of real-world shadows by keeping sharp contact shadows closer to the base and softening the farther the shadow stretches away.

• Global — quality mode selected globally in the Settings window is to be used for penumbra rendering.
• Disabled — penumbra rendering is disabled, shadow edges are crisp and sharp (no soft shadows at all).
• Low, Medium, High, Ultra — quality modes from the lowest to the best one, which has a more significant impact on performance.

Intensity of penumbra for the selected mode:

• Low values correspond to sharper shadow edges.
• Higher values increase penumbra size.

Enables or disables screen space shadows from the light source.

Number of rays used in screen space ray tracing. The higher the number of rays, the more accurate the computation of pixel shading is.

Number of Rays = 1	Number of Rays = 15

Number of steps each ray traces. The higher the number of steps, the more accurate the computation of pixel shading is.

Number of Steps = 4; Number of Rays = 1	Number of Steps = 32; Number of Rays = 1

Ray tracing dispersion. The higher the noise, the more chaotic the direction of rays is.

Noise Ray = 0.5	Noise Ray = 0

Dispersion of steps. The higher the noise, the more scattering the steps are.

Noise Step = 0.5; Noise Ray = 0.5	Noise Step = 0; Noise Ray = 0.5

Depending on the value of the Noise Ray parameter, the shadow may differ for the same values of Noise Step.

Noise Step = 0.5; Noise Ray = 0	Noise Step = 0; Noise Ray = 0

Length of each step used in ray-traced shadows within Near Step Size Distance.

• Low values cause the closest pixels to shade.
• Higher values lengthen the shadow spreading.
• Too high values can provoke shadow gaps.

Step Size = 0.5	Step Size = 20

Threshold value for Near Step Size. This value defines the limit of samples passing the screen-space shadowing.

• Low values let pass more samples which causes the shading of inappropriate pixels.
• Higher values can also cause inaccurate shading by limiting appropriate samples.

Threshold = 0

Threshold = 1

Threshold = 4

Size of the blur applied to the shadow edge.

• Low softness values corresponds to the crisp and sharp shadow edges.
• Higher softness values serve to accentuate the effect of soft indirect lighting.

Softness = 0	Softness = 0.5

Makes translucent shadows smoother by adding noise. The higher the value the more intense and noticeable the noise is.

Enables or disables lens flares from the light source. By default this effect is disabled.

A texture used to render billboards representing lens flares. The default texture is shown in the image below. For each billboard you can specify UV coordinates within this texture to determine its appearance. You can set your own texture, that contains the appearance for all the billboards to be used.

Lens flare occlusion fade value for the cases when the light source becomes occluded by an object. By the value of 0.0f, lens flares disappear abruptly, as the light source becomes occluded by an object. If 1.0f is set, lens flares will fade out gradually.

An offset of the center of lens flares from the world position of the light source.

Position Offset = (0.0, 0.0, 0.0)	Position Offset = (2.0, -3.0, 0.0)