Merge branch 'master' into DRTVWR-507-maint

1 files changed, 173 insertions, 0 deletions

diff --git a/indra/llrender/llatmosphere.h b/indra/llrender/llatmosphere.h
new file mode 100644
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+++ b/indra/llrender/llatmosphere.h
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+/** 
+ * @file llatmosphere.h
+ * @brief LLAtmosphere class
+ *
+ * $LicenseInfo:firstyear=2018&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2018, Linden Research, Inc.
+ * 
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * 
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+
+#ifndef LL_ATMOSPHERE_H
+#define LL_ATMOSPHERE_H
+
+#include "llglheaders.h"
+#include "llgltexture.h"
+
+// An atmosphere layer of width 'width' (in m), and whose density is defined as
+//   'exp_term' * exp('exp_scale' * h) + 'linear_term' * h + 'constant_term',
+// clamped to [0,1], and where h is the altitude (in m). 'exp_term' and
+// 'constant_term' are unitless, while 'exp_scale' and 'linear_term' are in
+// m^-1.
+class DensityLayer {
+ public:
+  DensityLayer()
+    : width(0.0f)
+    , exp_term(0.0f)
+    , exp_scale(0.0f)
+    , linear_term(0.0f)
+    , constant_term(0.0f)
+  {
+  }
+
+  DensityLayer(float width, float exp_term, float exp_scale, float linear_term, float constant_term)
+    : width(width)
+    , exp_term(exp_term)
+    , exp_scale(exp_scale)
+    , linear_term(linear_term)
+    , constant_term(constant_term)
+  {
+  }
+
+  bool operator==(const DensityLayer& rhs) const
+  {
+      if (width != rhs.width)
+      {
+         return false;
+      }
+
+      if (exp_term != rhs.exp_term)
+      {
+         return false;
+      }
+
+      if (exp_scale != rhs.exp_scale)
+      {
+         return false;
+      }
+
+      if (linear_term != rhs.linear_term)
+      {
+         return false;
+      }
+
+      if (constant_term != rhs.constant_term)
+      {
+         return false;
+      }
+
+      return true;
+  }
+
+  float width         = 1024.0f;
+  float exp_term      = 1.0f;
+  float exp_scale     = 1.0f;
+  float linear_term   = 1.0f;
+  float constant_term = 0.0f;
+};
+
+typedef std::vector<DensityLayer> DensityProfile;
+
+class AtmosphericModelSettings
+{
+public:
+    AtmosphericModelSettings();
+
+    AtmosphericModelSettings(
+        DensityProfile& rayleighProfile,
+        DensityProfile& mieProfile,
+        DensityProfile& absorptionProfile);
+
+    AtmosphericModelSettings(
+        F32             skyBottomRadius,
+        F32             skyTopRadius,
+        DensityProfile& rayleighProfile,
+        DensityProfile& mieProfile,
+        DensityProfile& absorptionProfile,
+        F32             sunArcRadians,
+        F32             mieAniso);
+
+    bool operator==(const AtmosphericModelSettings& rhs) const;
+
+    F32             m_skyBottomRadius;
+    F32             m_skyTopRadius;
+    DensityProfile  m_rayleighProfile;
+    DensityProfile  m_mieProfile;
+    DensityProfile  m_absorptionProfile;
+    F32             m_sunArcRadians;
+    F32             m_mieAnisotropy;
+};
+
+class LLAtmosphere
+{
+public:
+     LLAtmosphere();
+    ~LLAtmosphere();
+
+    static void initClass();
+    static void cleanupClass();
+
+    const LLAtmosphere& operator=(const LLAtmosphere& rhs)
+    {
+        LL_ERRS() << "Illegal operation!" << LL_ENDL;
+        return *this;
+    }
+
+    LLGLTexture* getTransmittance();
+    LLGLTexture* getScattering();
+    LLGLTexture* getMieScattering();
+    LLGLTexture* getIlluminance();
+
+    bool configureAtmosphericModel(AtmosphericModelSettings& settings);
+
+protected:    
+    LLAtmosphere(const LLAtmosphere& rhs)
+    {
+        *this = rhs;
+    }
+
+    LLPointer<LLGLTexture> m_transmittance;
+    LLPointer<LLGLTexture> m_scattering;
+    LLPointer<LLGLTexture> m_mie_scatter_texture;
+    LLPointer<LLGLTexture> m_illuminance;
+
+    std::vector<double> m_wavelengths;
+    std::vector<double> m_solar_irradiance;
+    std::vector<double> m_rayleigh_scattering;
+    std::vector<double> m_mie_scattering;
+    std::vector<double> m_mie_extinction;
+    std::vector<double> m_absorption_extinction;
+    std::vector<double> m_ground_albedo;
+
+    AtmosphericModelSettings m_settings;
+};
+
+extern LLAtmosphere* gAtmosphere;
+
+#endif // LL_ATMOSPHERE_H