virtualx-engine/doc/classes/DirectionalLight.xml
Hugo Locurcio 4fefb136ea
Backport DirectionalLight fade_start property to 3.x
- Implement shadow fading when using the Orthogonal shadow mode
  (like in `master`).

This allows customizing the distance at which directional shadows
start to fade away. Shadow fading will also always start at the same
distance now, regardless of the current shadow mode in use.

This is useful for enclosed levels to prevent shadows from fading
at all with a well-tuned maximum distance.

The default fade start value (0.8) results in fading happening later
in the distance compared to the previous behavior, where fading started
from the last shadow split distance (0.6 in PSSM 4 Splits and
0.1 in PSSM 2 Splits).
2023-11-20 12:41:55 +01:00

67 lines
6.1 KiB
XML

<?xml version="1.0" encoding="UTF-8" ?>
<class name="DirectionalLight" inherits="Light" version="3.6" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../class.xsd">
<brief_description>
Directional light from a distance, as from the Sun.
</brief_description>
<description>
A directional light is a type of [Light] node that models an infinite number of parallel rays covering the entire scene. It is used for lights with strong intensity that are located far away from the scene to model sunlight or moonlight. The worldspace location of the DirectionalLight transform (origin) is ignored. Only the basis is used to determine light direction.
</description>
<tutorials>
<link>$DOCS_URL/tutorials/3d/lights_and_shadows.html</link>
</tutorials>
<methods>
</methods>
<members>
<member name="directional_shadow_bias_split_scale" type="float" setter="set_param" getter="get_param" default="0.25">
Amount of extra bias for shadow splits that are far away. If self-shadowing occurs only on the splits far away, increasing this value can fix them. This is ignored when [member directional_shadow_mode] is [constant SHADOW_ORTHOGONAL].
</member>
<member name="directional_shadow_blend_splits" type="bool" setter="set_blend_splits" getter="is_blend_splits_enabled" default="false">
If [code]true[/code], shadow detail is sacrificed in exchange for smoother transitions between splits. Enabling shadow blend splitting also has a moderate performance cost. This is ignored when [member directional_shadow_mode] is [constant SHADOW_ORTHOGONAL].
</member>
<member name="directional_shadow_depth_range" type="int" setter="set_shadow_depth_range" getter="get_shadow_depth_range" enum="DirectionalLight.ShadowDepthRange" default="0">
Optimizes shadow rendering for detail versus movement. See [enum ShadowDepthRange].
</member>
<member name="directional_shadow_fade_start" type="float" setter="set_param" getter="get_param" default="0.8">
Proportion of [member directional_shadow_max_distance] at which point the shadow starts to fade. At [member directional_shadow_max_distance], the shadow will disappear. The default value is a balance between smooth fading and distant shadow visibility. If the camera moves fast and the [member directional_shadow_max_distance] is low, consider lowering [member directional_shadow_fade_start] below [code]0.8[/code] to make shadow transitions less noticeable. On the other hand, if you tuned [member directional_shadow_max_distance] to cover the entire scene, you can set [member directional_shadow_fade_start] to [code]1.0[/code] to prevent the shadow from fading in the distance (it will suddenly cut off instead).
</member>
<member name="directional_shadow_max_distance" type="float" setter="set_param" getter="get_param" default="100.0">
The maximum distance for shadow splits. Increasing this value will make directional shadows visible from further away, at the cost of lower overall shadow detail and performance (since more objects need to be included in the directional shadow rendering).
</member>
<member name="directional_shadow_mode" type="int" setter="set_shadow_mode" getter="get_shadow_mode" enum="DirectionalLight.ShadowMode" default="3">
The light's shadow rendering algorithm. See [enum ShadowMode].
</member>
<member name="directional_shadow_normal_bias" type="float" setter="set_param" getter="get_param" default="0.8">
Can be used to fix special cases of self shadowing when objects are perpendicular to the light.
</member>
<member name="directional_shadow_split_1" type="float" setter="set_param" getter="get_param" default="0.1">
The distance from camera to shadow split 1. Relative to [member directional_shadow_max_distance]. Only used when [member directional_shadow_mode] is [constant SHADOW_PARALLEL_2_SPLITS] or [constant SHADOW_PARALLEL_4_SPLITS].
</member>
<member name="directional_shadow_split_2" type="float" setter="set_param" getter="get_param" default="0.2">
The distance from shadow split 1 to split 2. Relative to [member directional_shadow_max_distance]. Only used when [member directional_shadow_mode] is [constant SHADOW_PARALLEL_2_SPLITS] or [constant SHADOW_PARALLEL_4_SPLITS].
</member>
<member name="directional_shadow_split_3" type="float" setter="set_param" getter="get_param" default="0.5">
The distance from shadow split 2 to split 3. Relative to [member directional_shadow_max_distance]. Only used when [member directional_shadow_mode] is [constant SHADOW_PARALLEL_4_SPLITS].
</member>
<member name="shadow_bias" type="float" setter="set_param" getter="get_param" overrides="Light" default="0.1" />
</members>
<constants>
<constant name="SHADOW_ORTHOGONAL" value="0" enum="ShadowMode">
Renders the entire scene's shadow map from an orthogonal point of view. This is the fastest directional shadow mode. May result in blurrier shadows on close objects.
</constant>
<constant name="SHADOW_PARALLEL_2_SPLITS" value="1" enum="ShadowMode">
Splits the view frustum in 2 areas, each with its own shadow map. This shadow mode is a compromise between [constant SHADOW_ORTHOGONAL] and [constant SHADOW_PARALLEL_4_SPLITS] in terms of performance.
</constant>
<constant name="SHADOW_PARALLEL_3_SPLITS" value="2" enum="ShadowMode">
Splits the view frustum in 3 areas, each with its own shadow map. This shadow mode is a compromise between [constant SHADOW_ORTHOGONAL] and [constant SHADOW_PARALLEL_4_SPLITS] in terms of performance.
</constant>
<constant name="SHADOW_PARALLEL_4_SPLITS" value="3" enum="ShadowMode">
Splits the view frustum in 4 areas, each with its own shadow map. This is the slowest directional shadow mode.
</constant>
<constant name="SHADOW_DEPTH_RANGE_STABLE" value="0" enum="ShadowDepthRange">
Keeps the shadow stable when the camera moves, at the cost of lower effective shadow resolution.
</constant>
<constant name="SHADOW_DEPTH_RANGE_OPTIMIZED" value="1" enum="ShadowDepthRange">
Tries to achieve maximum shadow resolution. May result in saw effect on shadow edges. This mode typically works best in games where the camera will often move at high speeds, such as most racing games.
</constant>
</constants>
</class>