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Diffstat (limited to 'indra/llrender/llatmosphere.cpp')
| -rw-r--r-- | indra/llrender/llatmosphere.cpp | 349 |
1 files changed, 349 insertions, 0 deletions
diff --git a/indra/llrender/llatmosphere.cpp b/indra/llrender/llatmosphere.cpp new file mode 100644 index 0000000000..12c6685354 --- /dev/null +++ b/indra/llrender/llatmosphere.cpp @@ -0,0 +1,349 @@ +/** + * @file llatmosphere.cpp + * @brief LLAtmosphere integration impl + * + * $LicenseInfo:firstyear=2018&license=viewerlgpl$ + * 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 + * $/LicenseInfo$ + */ + +#include "linden_common.h" + +#include "llatmosphere.h" +#include "llfasttimer.h" +#include "llsys.h" +#include "llglheaders.h" +#include "llrender.h" +#include "llshadermgr.h" +#include "llglslshader.h" + +LLAtmosphere* gAtmosphere = nullptr; + +// Values from "Reference Solar Spectral Irradiance: ASTM G-173", ETR column +// (see http://rredc.nrel.gov/solar/spectra/am1.5/ASTMG173/ASTMG173.html), +// summed and averaged in each bin (e.g. the value for 360nm is the average +// of the ASTM G-173 values for all wavelengths between 360 and 370nm). +// Values in W.m^-2. +const int kLambdaMin = 360; +const int kLambdaMax = 830; +const double kSolarIrradiance[48] = { + 1.11776, 1.14259, 1.01249, 1.14716, 1.72765, 1.73054, 1.6887, 1.61253, + 1.91198, 2.03474, 2.02042, 2.02212, 1.93377, 1.95809, 1.91686, 1.8298, + 1.8685, 1.8931, 1.85149, 1.8504, 1.8341, 1.8345, 1.8147, 1.78158, 1.7533, + 1.6965, 1.68194, 1.64654, 1.6048, 1.52143, 1.55622, 1.5113, 1.474, 1.4482, + 1.41018, 1.36775, 1.34188, 1.31429, 1.28303, 1.26758, 1.2367, 1.2082, + 1.18737, 1.14683, 1.12362, 1.1058, 1.07124, 1.04992 +}; + +// Values from http://www.iup.uni-bremen.de/gruppen/molspec/databases/ +// referencespectra/o3spectra2011/index.html for 233K, summed and averaged in +// each bin (e.g. the value for 360nm is the average of the original values +// for all wavelengths between 360 and 370nm). Values in m^2. +const double kOzoneCrossSection[48] = { + 1.18e-27, 2.182e-28, 2.818e-28, 6.636e-28, 1.527e-27, 2.763e-27, 5.52e-27, + 8.451e-27, 1.582e-26, 2.316e-26, 3.669e-26, 4.924e-26, 7.752e-26, 9.016e-26, + 1.48e-25, 1.602e-25, 2.139e-25, 2.755e-25, 3.091e-25, 3.5e-25, 4.266e-25, + 4.672e-25, 4.398e-25, 4.701e-25, 5.019e-25, 4.305e-25, 3.74e-25, 3.215e-25, + 2.662e-25, 2.238e-25, 1.852e-25, 1.473e-25, 1.209e-25, 9.423e-26, 7.455e-26, + 6.566e-26, 5.105e-26, 4.15e-26, 4.228e-26, 3.237e-26, 2.451e-26, 2.801e-26, + 2.534e-26, 1.624e-26, 1.465e-26, 2.078e-26, 1.383e-26, 7.105e-27 +}; + +// From https://en.wikipedia.org/wiki/Dobson_unit, in molecules.m^-2. +const double kDobsonUnit = 2.687e20; +// Maximum number density of ozone molecules, in m^-3 (computed so at to get +// 300 Dobson units of ozone - for this we divide 300 DU by the integral of +// the ozone density profile defined below, which is equal to 15km). +const double kMaxOzoneNumberDensity = 300.0 * kDobsonUnit / 15000.0; +const double kRayleigh = 1.24062e-6; +const double kRayleighScaleHeight = 8000.0; +const double kMieScaleHeight = 1200.0; +const double kMieAngstromAlpha = 0.0; +const double kMieAngstromBeta = 5.328e-3; +const double kMieSingleScatteringAlbedo = 0.9; +const double kGroundAlbedo = 0.1; + +const double max_sun_zenith_angle = F_PI * 2.0 / 3.0; + +AtmosphericModelSettings::AtmosphericModelSettings() + : m_skyBottomRadius(6360.0f) + , m_skyTopRadius(6420.0f) + , m_sunArcRadians(0.00045f) + , m_mieAnisotropy(0.8f) +{ + atmosphere::DensityProfileLayer rayleigh_density(0.0, 1.0, -1.0 / kRayleighScaleHeight, 0.0, 0.0); + atmosphere::DensityProfileLayer mie_density(0.0, 1.0, -1.0 / kMieScaleHeight, 0.0, 0.0); + + m_rayleighProfile.push_back(rayleigh_density); + m_mieProfile.push_back(mie_density); + + // Density profile increasing linearly from 0 to 1 between 10 and 25km, and + // decreasing linearly from 1 to 0 between 25 and 40km. This is an approximate + // profile from http://www.kln.ac.lk/science/Chemistry/Teaching_Resources/ + // Documents/Introduction%20to%20atmospheric%20chemistry.pdf (page 10). + m_absorptionProfile.push_back(atmosphere::DensityProfileLayer(25000.0, 0.0, 0.0, 1.0 / 15000.0, -2.0 / 3.0)); + m_absorptionProfile.push_back(atmosphere::DensityProfileLayer(0.0, 0.0, 0.0, -1.0 / 15000.0, 8.0 / 3.0)); +} + +AtmosphericModelSettings::AtmosphericModelSettings( + DensityProfile& rayleighProfile, + DensityProfile& mieProfile, + DensityProfile& absorptionProfile) +: m_skyBottomRadius(6360.0f) +, m_skyTopRadius(6420.0f) +, m_rayleighProfile(rayleighProfile) +, m_mieProfile(mieProfile) +, m_absorptionProfile(absorptionProfile) +, m_sunArcRadians(0.00045f) +, m_mieAnisotropy(0.8f) +{ +} + +AtmosphericModelSettings::AtmosphericModelSettings( + F32 skyBottomRadius, + F32 skyTopRadius, + DensityProfile& rayleighProfile, + DensityProfile& mieProfile, + DensityProfile& absorptionProfile, + F32 sunArcRadians, + F32 mieAniso) +: m_skyBottomRadius(skyBottomRadius) +, m_skyTopRadius(skyTopRadius) +, m_rayleighProfile(rayleighProfile) +, m_mieProfile(mieProfile) +, m_absorptionProfile(absorptionProfile) +, m_sunArcRadians(sunArcRadians) +, m_mieAnisotropy(mieAniso) +{ +} + +bool AtmosphericModelSettings::operator==(const AtmosphericModelSettings& rhs) const +{ + if (m_skyBottomRadius != rhs.m_skyBottomRadius) + { + return false; + } + + if (m_skyTopRadius != rhs.m_skyTopRadius) + { + return false; + } + + if (m_sunArcRadians != rhs.m_sunArcRadians) + { + return false; + } + + if (m_mieAnisotropy != rhs.m_mieAnisotropy) + { + return false; + } + + if (m_rayleighProfile != rhs.m_rayleighProfile) + { + return false; + } + + if (m_mieProfile != rhs.m_mieProfile) + { + return false; + } + + if (m_absorptionProfile != rhs.m_absorptionProfile) + { + return false; + } + + return true; +} + +void LLAtmosphere::initClass() +{ + if (!gAtmosphere) + { + gAtmosphere = new LLAtmosphere; + } +} + +void LLAtmosphere::cleanupClass() +{ + if(gAtmosphere) + { + delete gAtmosphere; + } + gAtmosphere = NULL; +} + +LLAtmosphere::LLAtmosphere() +{ + for (int l = kLambdaMin; l <= kLambdaMax; l += 10) + { + double lambda = static_cast<double>(l) * 1e-3; // micro-meters + double mie = kMieAngstromBeta / kMieScaleHeight * pow(lambda, -kMieAngstromAlpha); + m_wavelengths.push_back(l); + m_solar_irradiance.push_back(kSolarIrradiance[(l - kLambdaMin) / 10]); + m_rayleigh_scattering.push_back(kRayleigh * pow(lambda, -4)); + m_mie_scattering.push_back(mie * kMieSingleScatteringAlbedo); + m_mie_extinction.push_back(mie); + m_absorption_extinction.push_back(kMaxOzoneNumberDensity * kOzoneCrossSection[(l - kLambdaMin) / 10]); + m_ground_albedo.push_back(kGroundAlbedo); + } + + AtmosphericModelSettings defaults; + configureAtmosphericModel(defaults); +} + +LLAtmosphere::~LLAtmosphere() +{ + // Cease referencing textures from atmosphere::model from our LLGLTextures wrappers for same. + if (m_transmittance) + { + m_transmittance->setTexName(0); + } + + if (m_scattering) + { + m_scattering->setTexName(0); + } + + if (m_mie_scatter_texture) + { + m_mie_scatter_texture->setTexName(0); + } + + delete m_model; + m_model = nullptr; +} + +bool LLAtmosphere::configureAtmosphericModel(AtmosphericModelSettings& settings) +{ + if ((m_model != nullptr) && (settings == m_settings)) + { + return true; + } + + if (m_model) + { + delete m_model; + } + m_model = nullptr; + + getTransmittance()->setTexName(0); + getScattering()->setTexName(0); + getMieScattering()->setTexName(0); + getIlluminance()->setTexName(0); + + // Init libatmosphere model + m_model = new atmosphere::Model( + m_config, + m_wavelengths, + m_solar_irradiance, + settings.m_sunArcRadians, + settings.m_skyBottomRadius * 1000.0f, + settings.m_skyTopRadius * 1000.0f, + settings.m_rayleighProfile, + m_rayleigh_scattering, + settings.m_mieProfile, + m_mie_scattering, + m_mie_extinction, + settings.m_mieAnisotropy, + settings.m_absorptionProfile, + m_absorption_extinction, + m_ground_albedo, + max_sun_zenith_angle, + 1000.0, + 3, + false, // do not combine_scattering...we want indep textures + false, // use 32F for 2d textures to avoid artifacts + true); // use 16F for 3d textures to reduce footprint + + if (m_model) + { + m_model->Init(m_config, m_textures); + getTransmittance()->setTexName(m_textures.transmittance_texture); + getScattering()->setTexName(m_textures.scattering_texture); + getMieScattering()->setTexName(m_textures.single_mie_scattering_texture); + getIlluminance()->setTexName(m_textures.illuminance_texture); + m_settings = settings; + } + + return m_model != nullptr; +} + +LLGLTexture* LLAtmosphere::getTransmittance() +{ + if (!m_transmittance) + { + m_transmittance = new LLGLTexture; + m_transmittance->generateGLTexture(); + m_transmittance->setAddressMode(LLTexUnit::eTextureAddressMode::TAM_CLAMP); + m_transmittance->setFilteringOption(LLTexUnit::eTextureFilterOptions::TFO_BILINEAR); + m_transmittance->setExplicitFormat(GL_RGB32F_ARB, GL_RGB, GL_FLOAT); + m_transmittance->setTarget(GL_TEXTURE_2D, LLTexUnit::TT_TEXTURE); + } + return m_transmittance; +} + +LLGLTexture* LLAtmosphere::getScattering() +{ + if (!m_scattering) + { + m_scattering = new LLGLTexture; + m_scattering->generateGLTexture(); + m_scattering->setAddressMode(LLTexUnit::eTextureAddressMode::TAM_CLAMP); + m_scattering->setFilteringOption(LLTexUnit::eTextureFilterOptions::TFO_BILINEAR); + m_scattering->setExplicitFormat(GL_RGB16F_ARB, GL_RGB, GL_FLOAT); + m_scattering->setTarget(GL_TEXTURE_3D, LLTexUnit::TT_TEXTURE_3D); + } + return m_scattering; +} + +LLGLTexture* LLAtmosphere::getMieScattering() +{ + if (!m_mie_scatter_texture) + { + m_mie_scatter_texture = new LLGLTexture; + m_mie_scatter_texture->generateGLTexture(); + m_mie_scatter_texture->setAddressMode(LLTexUnit::eTextureAddressMode::TAM_CLAMP); + m_mie_scatter_texture->setFilteringOption(LLTexUnit::eTextureFilterOptions::TFO_BILINEAR); + m_mie_scatter_texture->setExplicitFormat(GL_RGB16F_ARB, GL_RGB, GL_FLOAT); + m_mie_scatter_texture->setTarget(GL_TEXTURE_3D, LLTexUnit::TT_TEXTURE_3D); + } + return m_mie_scatter_texture; +} + +LLGLTexture* LLAtmosphere::getIlluminance() +{ + if (!m_illuminance) + { + m_illuminance = new LLGLTexture; + m_illuminance->generateGLTexture(); + m_illuminance->setAddressMode(LLTexUnit::eTextureAddressMode::TAM_CLAMP); + m_illuminance->setFilteringOption(LLTexUnit::eTextureFilterOptions::TFO_BILINEAR); + m_illuminance->setExplicitFormat(GL_RGB32F_ARB, GL_RGB, GL_FLOAT); + m_illuminance->setTarget(GL_TEXTURE_2D, LLTexUnit::TT_TEXTURE); + } + return m_illuminance; +} + +GLhandleARB LLAtmosphere::getAtmosphericShaderForLink() const +{ + return m_model ? m_model->GetShader() : 0; +} |