Shadow

In the 3D world, light and shadow have always been extremely important components that enrich the entire environment. High quality shadows can make the game world look more realistic.

Cocos Creator 3.0 currently supports both Planar and ShadowMap shadow types.

shadow

Enable Shadow Effect

To enable the shadow effect for an object, proceed as follows:

  1. Check Scene in the Hierarchy panel, and then check the Enabled property in the Shadows component of the Inspector panel.

    enable-shadow

  2. Select the 3D node that needs to display shadows in the Hierarchy panel, and then set the ShadowCastingMode property to ON in the MeshRenderer component of the Inspector panel.

    set-meshRenderer

    If the shadow type is ShadowMap, set the ReceiveShadow property on the MeshRenderer component to ON.

Note: if the shadows are not displayed properly, adjust the direction of the directional light.

Shadow Type

The shadow type can be set in the Type property of the Shadows component.

Planar Shadow

The Planar shadow type is generally used for simpler scenes.

planar-properties

PropertyDescription
EnabledWhether to enable shadow effect
TypeShadow type
ShadowColorShadow color
NormalThe normal line perpendicular to the shadow, used to adjust the slope of the shadow
DistanceThe distance of the shadow in the direction of the normal to the origin of the coordinate

Adjust the direction of the directional light to adjust the position of the shadow.

Note: planar shadows are only cast on planar surfaces, not on objects, which means that the ReceiveShadow property in the MeshRenderer component is invalid.

ShadowMap

ShadowMap renders the scene with the lights as the viewpoint. From the position of the lights, the places in the scene that are not visible are where the shadows are created.

shadow map panel details

PropertyExplanation
EnabledWhether to enable the shadow effect
TypeChoose the shadow type
ShadowColorColor value of the resulting shadow
PcfSet the anti-aliasing level of the shadow edge, currently including HARD, FILTER_X5, FILTER_X9, FILTER_X25. Please refer to the section PCF Soft Shadow below for details.
AutoAdaptIf checked, the range of shadows will be calculated automatically, as described in section AutoAdapt Adaptive Shadow Calculation below. If this option is unchecked, the following properties are enabled to manually set the range of shadow generation.
NearSet the near clipping plane of the main lights shadow camera
FarSet the far clipping plane of the main lights shadow camera
OrthoSizeSet the ortho viewport size of the main lights shadow camera
MaxReceivedThe maximum number of lights supported for shadow generation, default is 4, can be adjusted as needed.
ShadowMapSizeSet the texture size of the shadow
AspectSet the ortho viewport aspect ratio of the main lights shadow camera
BiasSet the shadow offset value to prevent z-fitting.

ShadowMap receives and displays shadow effects generated by other objects when ReceiveShadow on the object MeshRenderer component is enabled.

ShadowMap is generally used for scenes that require more realistic and complex light and shadow effects. The downside is that if the lights is not moved, then the previously generated Shadow Map can be reused, while once the lights is moved, then a new ShadowMap needs to be recalculated.

PCF Soft Shadow

Percentage Closer Filtering (PCF) is a simple, common technique used to achieve shadow edge desampling, by smoothing shadow edges to eliminate jaggedness in shadow mapping. The principle is to sample around the current pixel (also called a fragment), then calculate the ratio of the sample closer to the lights compared to the fragment, use this ratio to scale the scattered light and specular light, and then color the fragment to blur the shadow edges.

Cocos Creator currently supports 5x, 9x, and 25x sampling. The larger the magnification, the larger the sampling area and the more blurred the shadow edges.

AutoAdapt Adaptive Shadow Calculation

AutoAdapt adaptive shadow calculation will automatically calculate the range of shadows created under the lightView, as well as the distance of the shadow camera.

Support dynamic batching to improve performance

For models with instancing enabled in the material, the planar shadow will automatically draw with instancing as well, see the Dynamic Batching documentation for details.