ライト

In the real world, the environment around you is lit from many sources. The Sun, street lights, TV screens and so on. In a PlayCanvas scene, you have the ability to set up a number of different types of light sources and the shape of the light source to approximate the different types of light we find in reality.

Descriptions of each light type and light source shape are below and examples of different combinations of light types and given in table below.

Light Types

PlayCanvasには3つの種類のライトがあります：

• Directional lights
• Omni lights
• Spot lights

指向性ライト

最も身近な光源は太陽です。太陽は地球から非常に遠いので、地球の表面に当たる光は単一方向を向くよう近似することができます。PlayCanvasでは、このタイプの光源を指向性ライトと呼びます。

選択していない場合、指向性ライトはエディタの3Dビュー内で次のアイコンで表されます。

HierarchyパネルとInspectorパネルでライトを選択するには、このアイコンをクリックします。

指向性ライトは次のようにオブジェクトを照らします：

Omni Lights

Omni lights are light sources that emit light in all directions. An example of this type of light source is a candle and other examples can be seen in the table below.

When unselected, a omni light is represented by the following icon in the Editor's 3D view:

HierarchyパネルとInspectorパネルでライトを選択するには、このアイコンをクリックします。

An omni light lights an object like this:

スポットライト

Spot lights, like omni lights, emit light in all directions. However, the light from the spot light is constrained to a cone shape.

選択していない場合、スポットライトはエディタの3Dビュー内で次のアイコンで表されます

HierarchyパネルとInspectorパネルでライトを選択するには、このアイコンをクリックします。

スポットライトは次のようにオブジェクトを照らします：

Light Shapes

There are four light source shapes:

• Punctual
• Rectangle
• Disk
• Sphere

Punctual

The punctual light source shape is an infinitesimally small point. This is the default light source shape and is a less physically correct, but relatively low cost approximation of a light source. The other light source shapes are more costly to render but will give more correct lighting and specular reflections.

Rectangle

The rectangle light source shape is a flat 4 sided shape with a specified width and height.

Disk

The disk light source shape is a round and flat light shape with a specified radius.

Sphere

The sphere light source shape is ball shaped with a specified radius.

ユースケース

Below is a table of some common use cases each light source shape and light type:

x = no common use cases - but still can be used for application/game specific lighting effects.

パフォーマンスについて

Light sources with Rectangle, Disk and Sphere shapes do cost more to render than Punctual lights, so use Punctual light source shapes if you have relatively small light sources or do not have reflective surfaces where Punctual lights would appear visibly incorrect.