Merged in SL-16127 (pull request #741)

SL-16127

Approved-by: Euclid Linden
Approved-by: Dave Parks

indra/llinventory/llsettingssky.cpp

@@ -1209,6 +1209,14 @@ LLColor3 LLSettingsSky::getLightTransmittance(F32 distance) const
     return transmittance;
 }
 
+// SL-16127: getTotalDensity() and getDensityMultiplier() call LLSettingsSky::getColor() and LLSettingsSky::getFloat() respectively which are S-L-O-W
+LLColor3 LLSettingsSky::getLightTransmittanceFast( const LLColor3& total_density, const F32 density_multiplier, const F32 distance ) const
+{
+    // Transparency (-> density) from Beer's law
+    LLColor3 transmittance = componentExp(total_density * -(density_multiplier * distance));
+    return transmittance;
+}
+
 // performs soft scale clip and gamma correction ala the shader implementation
 // scales colors down to 0 - 1 range preserving relative ratios
 LLColor3 LLSettingsSky::gammaCorrect(const LLColor3& in) const

indra/llinventory/llsettingssky.h

@@ -252,6 +252,7 @@ class LLSettingsSky: public LLSettingsBase
 
     LLColor3 getLightAttenuation(F32 distance) const;
     LLColor3 getLightTransmittance(F32 distance) const;
+    LLColor3 getLightTransmittanceFast(const LLColor3& total_density, const F32 density_multiplier, const F32 distance) const;
     LLColor3 getTotalDensity() const;
     LLColor3 gammaCorrect(const LLColor3& in) const;
 

indra/newview/lllegacyatmospherics.cpp

@@ -211,8 +211,8 @@ LLColor4 LLAtmospherics::calcSkyColorInDir(AtmosphericsVars& vars, const LLVecto
 // This cubemap is used as "environmentMap" in indra/newview/app_settings/shaders/class2/deferred/softenLightF.glsl
 LLColor4 LLAtmospherics::calcSkyColorInDir(const LLSettingsSky::ptr_t &psky, AtmosphericsVars& vars, const LLVector3 &dir, bool isShiny)
 {
-	F32 sky_saturation = 0.25f;
-	F32 land_saturation = 0.1f;
+	const F32 sky_saturation = 0.25f;
+	const F32 land_saturation = 0.1f;
 
 	if (isShiny && dir.mV[VZ] < -0.02f)
 	{
@@ -270,11 +270,12 @@ LLColor4 LLAtmospherics::calcSkyColorInDir(const LLSettingsSky::ptr_t &psky, Atm
 //       indra\newview\lllegacyatmospherics.cpp
 void LLAtmospherics::calcSkyColorWLVert(const LLSettingsSky::ptr_t &psky, LLVector3 & Pn, AtmosphericsVars& vars)
 {
-    LLColor3    blue_density = vars.blue_density;
-    LLColor3    blue_horizon = vars.blue_horizon;
-    F32         haze_horizon = vars.haze_horizon;
-    F32         haze_density = vars.haze_density;
-    F32         density_multiplier = vars.density_multiplier;
+    const LLColor3    blue_density = vars.blue_density;
+    const LLColor3    blue_horizon = vars.blue_horizon;
+    const F32         haze_horizon = vars.haze_horizon;
+    const F32         haze_density = vars.haze_density;
+    const F32         density_multiplier = vars.density_multiplier;
+
     F32         max_y = vars.max_y;
     LLVector4   sun_norm = vars.sun_norm;
 
@@ -313,7 +314,7 @@ void LLAtmospherics::calcSkyColorWLVert(const LLSettingsSky::ptr_t &psky, LLVect
 	// Sunlight attenuation effect (hue and brightness) due to atmosphere
 	// this is used later for sunlight modulation at various altitudes
 	LLColor3 light_atten = vars.light_atten;
-    LLColor3 light_transmittance = psky->getLightTransmittance(Plen);
+    LLColor3 light_transmittance = psky->getLightTransmittanceFast(vars.total_density, vars.density_multiplier, Plen);
     (void)light_transmittance; // silence Clang warn-error
 
 	// Calculate relative weights

indra/newview/llvosky.h

@@ -214,12 +214,12 @@ class LLVOSky : public LLStaticViewerObject
 	// Initialize/delete data that's only inited once per class.
 	void init();
 	void initCubeMap();
-	void initEmpty();
 	
 	void cleanupGL();
 	void restoreGL();
 
     void calc();
+    void cacheEnvironment(LLSettingsSky::ptr_t psky, AtmosphericsVars& atmosphericsVars);
 
 	/*virtual*/ void idleUpdate(LLAgent &agent, const F64 &time);
 	bool updateSky();
@@ -253,8 +253,6 @@ class LLVOSky : public LLStaticViewerObject
     LLColor4 getSkyFogColor() const                        { return m_legacyAtmospherics.getFogColor(); }
     LLColor4 getGLFogColor() const                      { return m_legacyAtmospherics.getGLFogColor(); }
 
-    LLColor4U getFadeColor() const;
-
 	void setCloudDensity(F32 cloud_density)				{ mCloudDensity = cloud_density; }
 	void setWind ( const LLVector3& wind )				{ mWind = wind.length(); }
 
@@ -299,10 +297,10 @@ class LLVOSky : public LLStaticViewerObject
 protected:
 	~LLVOSky();
 
-	void updateDirections(void);
+	void updateDirections(LLSettingsSky::ptr_t psky);
 
 	void initSkyTextureDirs(const S32 side, const S32 tile);
-	void createSkyTexture(AtmosphericsVars& vars, const S32 side, const S32 tile);
+	void createSkyTexture(LLSettingsSky::ptr_t psky, AtmosphericsVars& vars, const S32 side, const S32 tile);
 
 	LLPointer<LLViewerFetchedTexture> mSunTexturep[2];
 	LLPointer<LLViewerFetchedTexture> mMoonTexturep[2];