Merge remote-tracking branch 'origin/5.12' into 5.13

Change-Id: Id2885cdbb45f8aa701e218b6201f0a3732b7ef11

1 files changed, 24 insertions, 0 deletions

diff --git a/src/render/lights/qspotlight.cpp b/src/render/lights/qspotlight.cpp
index 81c18387b..c4deaf817 100644
--- a/src/render/lights/qspotlight.cpp
+++ b/src/render/lights/qspotlight.cpp
@@ -83,6 +83,18 @@ QSpotLightPrivate::QSpotLightPrivate()
   \since 5.5
   \brief Encapsulate a Spot Light object in a Qt 3D scene.
 
+    A spotlight is a light source that emits a cone of light in a particular direction.
+
+    A spotlight uses three attenuation factors to describe how the intensity of the light
+    decreases over distance. These factors are designed to be used together in calcuating total
+    attenuation. For the materials in Qt3D Extras the following formula is used, where distance
+    is the distance from the light to the surface being rendered:
+
+    \code
+    totalAttenuation = 1.0 / (constantAttenuation + (linearAttenuation * distance) + (quadraticAttenuation * distance * distance));
+    \endcode
+
+    Custom materials may choose to interpret these factors differently.
  */
 
 /*!
@@ -93,6 +105,18 @@ QSpotLightPrivate::QSpotLightPrivate()
     \since 5.5
     \brief Encapsulate a Spot Light object in a Qt 3D scene.
 
+    A spotlight is a light source that emits a cone of light in a particular direction.
+
+    A spotlight uses three attenuation factors to describe how the intensity of the light
+    decreases over distance. These factors are designed to be used together in calcuating total
+    attenuation. For the materials in Qt3D Extras the following formula is used, where distance
+    is the distance from the light to the surface being rendered:
+
+    \code
+    totalAttenuation = 1.0 / (constantAttenuation + (linearAttenuation * distance) + (quadraticAttenuation * distance * distance));
+    \endcode
+
+    Custom materials may choose to interpret these factors differently.
 */
 
 /*!