From 77bc2d4e6d1ad197792a73b17d2e5fed4d8fe48f Mon Sep 17 00:00:00 2001
From: Jonathas Costa <jon.costa@gmailcom>
Date: Wed, 24 Jul 2019 15:52:27 -0400
Subject: [PATCH] Improved Mars illumination.

---
 .../scene/solarsystem/planets/mars/atmosphere.asset   |  2 ++
 modules/atmosphere/rendering/renderableatmosphere.cpp | 11 ++++++++++-
 modules/atmosphere/rendering/renderableatmosphere.h   |  1 +
 3 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/data/assets/scene/solarsystem/planets/mars/atmosphere.asset b/data/assets/scene/solarsystem/planets/mars/atmosphere.asset
index 2850e528ca..bffdc14094 100644
--- a/data/assets/scene/solarsystem/planets/mars/atmosphere.asset
+++ b/data/assets/scene/solarsystem/planets/mars/atmosphere.asset
@@ -16,6 +16,8 @@ local Atmosphere = {
             PlanetRadius = 3386.190,
             PlanetAverageGroundReflectance = 0.1,
             GroundRadianceEmittion = 0.37,
+            SunIntensity = 6.7,
+            MieScatteringExtinctionPropCoefficient = 0.23862,
             Rayleigh = {
                 Coefficients = {
                     -- Wavelengths are given in 10^-9m
diff --git a/modules/atmosphere/rendering/renderableatmosphere.cpp b/modules/atmosphere/rendering/renderableatmosphere.cpp
index d7e556384d..232a70b011 100644
--- a/modules/atmosphere/rendering/renderableatmosphere.cpp
+++ b/modules/atmosphere/rendering/renderableatmosphere.cpp
@@ -266,6 +266,7 @@ RenderableAtmosphere::RenderableAtmosphere(const ghoul::Dictionary& dictionary)
     , _mieHeightScale(0.f)
     , _miePhaseConstant(0.f)
     , _sunRadianceIntensity(5.f)
+    , _mieScattExtPropCoefProp(1.f)
     , _mieExtinctionCoeff(glm::vec3(0.f))
     , _rayleighScatteringCoeff(glm::vec3(0.f))
     , _ozoneExtinctionCoeff(glm::vec3(0.f))
@@ -409,6 +410,12 @@ RenderableAtmosphere::RenderableAtmosphere(const ghoul::Dictionary& dictionary)
                                                                SunIntensityInfo.identifier
                                                               );
         }
+        
+        if (atmosphereDictionary.hasKey(MieScatteringExtinctionPropCoeffInfo.identifier)) {
+            _mieScattExtPropCoefProp = atmosphereDictionary.value<float>(
+                MieScatteringExtinctionPropCoeffInfo.identifier
+                );
+        }
 
         if (!atmosphereDictionary.getValue(
                 GroundRadianceEmittioninfo.identifier,
@@ -634,8 +641,10 @@ RenderableAtmosphere::RenderableAtmosphere(const ghoul::Dictionary& dictionary)
             _mieScatteringCoeffZP.onChange(updateAtmosphere);
             addProperty(_mieScatteringCoeffZP);
 
-            _mieScatteringExtinctionPropCoefficientP =
+            _mieScatteringExtinctionPropCoefficientP = 
+                _mieScattExtPropCoefProp != 1.f ? _mieScattExtPropCoefProp :
                 _mieScatteringCoeff.x / _mieExtinctionCoeff.x;
+
             _mieScatteringExtinctionPropCoefficientP.onChange(updateAtmosphere);
             addProperty(_mieScatteringExtinctionPropCoefficientP);
 
diff --git a/modules/atmosphere/rendering/renderableatmosphere.h b/modules/atmosphere/rendering/renderableatmosphere.h
index d86f068ca7..202933b593 100644
--- a/modules/atmosphere/rendering/renderableatmosphere.h
+++ b/modules/atmosphere/rendering/renderableatmosphere.h
@@ -122,6 +122,7 @@ private:
     float _mieHeightScale;
     float _miePhaseConstant;
     float _sunRadianceIntensity;
+    float _mieScattExtPropCoefProp;
 
     glm::vec3 _mieExtinctionCoeff;
     glm::vec3 _rayleighScatteringCoeff;