Files
OpenSpace/modules/atmosphere/rendering/atmospheredeferredcaster.cpp
2018-07-05 14:40:54 -04:00

1603 lines
67 KiB
C++

/*****************************************************************************************
* *
* OpenSpace *
* *
* Copyright (c) 2014-2018 *
* *
* Permission is hereby granted, free of charge, to any person obtaining a copy of this *
* software and associated documentation files (the "Software"), to deal in the Software *
* without restriction, including without limitation the rights to use, copy, modify, *
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to *
* permit persons to whom the Software is furnished to do so, subject to the following *
* conditions: *
* *
* The above copyright notice and this permission notice shall be included in all copies *
* or substantial portions of the Software. *
* *
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, *
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A *
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT *
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF *
* CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE *
* OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
****************************************************************************************/
/***************************************************************************************
* Modified part of the code (4D texture mechanism) from Eric Bruneton is used in the
* following code.
****************************************************************************************/
/**
* Precomputed Atmospheric Scattering
* Copyright (c) 2008 INRIA
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <modules/atmosphere/rendering/atmospheredeferredcaster.h>
#include <modules/atmosphere/rendering/renderableatmosphere.h>
#include <openspace/engine/openspaceengine.h>
#include <openspace/util/powerscaledcoordinate.h>
#include <openspace/util/updatestructures.h>
#include <openspace/util/spicemanager.h>
#include <openspace/rendering/renderable.h>
#include <openspace/rendering/renderengine.h>
#include <openspace/rendering/renderer.h>
#include <ghoul/glm.h>
#include <ghoul/filesystem/filesystem.h>
#include <ghoul/logging/logmanager.h>
#include <ghoul/opengl/ghoul_gl.h>
#include <ghoul/opengl/programobject.h>
#include <ghoul/opengl/texture.h>
#include <ghoul/opengl/textureunit.h>
#include <glm/gtx/string_cast.hpp>
#include <glm/gtc/matrix_transform.hpp>
#include <glm/gtx/transform.hpp>
#include <glm/gtx/vector_angle.hpp>
#include <glm/gtc/quaternion.hpp>
#include <sstream>
#include <fstream>
#ifdef WIN32
#define _USE_MATH_DEFINES
#endif // WIN32
#include <math.h>
namespace {
constexpr const char* _loggerCat = "AtmosphereDeferredcaster";
constexpr const char* GlslDeferredcastPath =
"${MODULES}/atmosphere/shaders/atmosphere_deferred_fs.glsl";
constexpr const char* GlslDeferredcastFSPath =
"${MODULES}/atmosphere/shaders/atmosphere_deferred_fs.glsl";
constexpr const char* GlslDeferredcastVsPath =
"${MODULES}/atmosphere/shaders/atmosphere_deferred_vs.glsl";
constexpr const float ATM_EPS = 2.f;
constexpr const float KM_TO_M = 1000.f;
} // namespace
namespace openspace {
AtmosphereDeferredcaster::AtmosphereDeferredcaster()
: _transmittanceProgramObject(nullptr)
, _irradianceProgramObject(nullptr)
, _irradianceSupTermsProgramObject(nullptr)
, _irradianceFinalProgramObject(nullptr)
, _inScatteringProgramObject(nullptr)
, _inScatteringSupTermsProgramObject(nullptr)
, _deltaEProgramObject(nullptr)
, _deltaSProgramObject(nullptr)
, _deltaSSupTermsProgramObject(nullptr)
, _deltaJProgramObject(nullptr)
, _atmosphereProgramObject(nullptr)
, _transmittanceTableTexture(0)
, _irradianceTableTexture(0)
, _inScatteringTableTexture(0)
, _deltaETableTexture(0)
, _deltaSRayleighTableTexture(0)
, _deltaSMieTableTexture(0)
, _deltaJTableTexture(0)
, _atmosphereTexture(0)
, _atmosphereCalculated(false)
, _ozoneEnabled(false)
, _sunFollowingCameraEnabled(false)
, _atmosphereRadius(0.f)
, _atmospherePlanetRadius(0.f)
, _planetAverageGroundReflectance(0.f)
, _planetGroundRadianceEmittion(0.f)
, _rayleighHeightScale(0.f)
, _ozoneHeightScale(0.f)
, _mieHeightScale(0.f)
, _miePhaseConstant(0.f)
, _sunRadianceIntensity(50.0f)
, _rayleighScatteringCoeff(glm::vec3(0.f))
, _ozoneExtinctionCoeff(glm::vec3(0.f))
, _mieScatteringCoeff(glm::vec3(0.f))
, _mieExtinctionCoeff(glm::vec3(0.f))
, _ellipsoidRadii(glm::dvec3(0.0))
, _transmittance_table_width(256)
, _transmittance_table_height(64)
, _irradiance_table_width(64)
, _irradiance_table_height(16)
, _delta_e_table_width(64)
, _delta_e_table_height(16)
, _r_samples(32)
, _mu_samples(128)
, _mu_s_samples(32)
, _nu_samples(8)
, _hardShadowsEnabled(false)
, _calculationTextureScale(1.0)
, _saveCalculationTextures(false)
{}
void AtmosphereDeferredcaster::initialize() {
if (!_atmosphereCalculated) {
preCalculateAtmosphereParam();
}
}
void AtmosphereDeferredcaster::deinitialize() {
_transmittanceProgramObject = nullptr;
_irradianceProgramObject = nullptr;
_irradianceSupTermsProgramObject = nullptr;
_inScatteringProgramObject = nullptr;
_inScatteringSupTermsProgramObject = nullptr;
_deltaEProgramObject = nullptr;
_deltaSProgramObject = nullptr;
_deltaSSupTermsProgramObject = nullptr;
_deltaJProgramObject = nullptr;
glDeleteTextures(1, &_transmittanceTableTexture);
glDeleteTextures(1, &_irradianceTableTexture);
glDeleteTextures(1, &_inScatteringTableTexture);
glDeleteTextures(1, &_deltaETableTexture);
glDeleteTextures(1, &_deltaSRayleighTableTexture);
glDeleteTextures(1, &_deltaSMieTableTexture);
glDeleteTextures(1, &_deltaJTableTexture);
glDeleteTextures(1, &_atmosphereTexture);
}
void AtmosphereDeferredcaster::preRaycast(const RenderData& renderData,
const DeferredcastData&,
ghoul::opengl::ProgramObject& program)
{
// Atmosphere Frustum Culling
glm::dvec3 tPlanetPosWorld = glm::dvec3(
_modelTransform * glm::dvec4(0.0, 0.0, 0.0, 1.0)
);
const double distance = glm::distance(
tPlanetPosWorld,
renderData.camera.eyePositionVec3()
);
// Radius is in KM
const double scaledRadius = glm::length(
glm::dmat3(_modelTransform) * glm::dvec3(1000.0 * _atmosphereRadius, 0.0, 0.0)
);
if (distance > scaledRadius * DISTANCE_CULLING_RADII) {
program.setUniform(_uniformCache.cullAtmosphere, 1);
}
else {
glm::dmat4 MV = glm::dmat4(
renderData.camera.sgctInternal.projectionMatrix()
) * renderData.camera.combinedViewMatrix();
if (!isAtmosphereInFrustum(
MV,
tPlanetPosWorld,
(_atmosphereRadius + ATM_EPS)*KM_TO_M)
)
{
program.setUniform(_uniformCache.cullAtmosphere, 1);
}
else {
program.setUniform(_uniformCache.cullAtmosphere, 0);
program.setUniform(_uniformCache.Rg, _atmospherePlanetRadius);
program.setUniform(_uniformCache.Rt, _atmosphereRadius);
program.setUniform(
_uniformCache.groundRadianceEmittion,
_planetGroundRadianceEmittion
);
program.setUniform(_uniformCache.HR, _rayleighHeightScale);
program.setUniform(_uniformCache.betaRayleigh, _rayleighScatteringCoeff);
program.setUniform(_uniformCache.HM, _mieHeightScale);
program.setUniform(_uniformCache.betaMieExtinction, _mieExtinctionCoeff);
program.setUniform(_uniformCache.mieG, _miePhaseConstant);
program.setUniform(_uniformCache.sunRadiance, _sunRadianceIntensity);
program.setUniform(_uniformCache.ozoneLayerEnabled, _ozoneEnabled);
program.setUniform(_uniformCache.HO, _ozoneHeightScale);
program.setUniform(_uniformCache.betaOzoneExtinction, _ozoneExtinctionCoeff);
program.setUniform(_uniformCache.SAMPLES_R, _r_samples);
program.setUniform(_uniformCache.SAMPLES_MU, _mu_samples);
program.setUniform(_uniformCache.SAMPLES_MU_S, _mu_s_samples);
program.setUniform(_uniformCache.SAMPLES_NU, _nu_samples);
// Object Space
glm::dmat4 inverseModelMatrix = glm::inverse(_modelTransform);
program.setUniform(
_uniformCache2.dInverseModelTransformMatrix,
inverseModelMatrix
);
program.setUniform(_uniformCache2.dModelTransformMatrix, _modelTransform);
// Eye Space in SGCT to Eye Space in OS (SGCT View to OS Camera Rig)
glm::dmat4 dSgctEye2OSEye = glm::inverse(
glm::dmat4(renderData.camera.viewMatrix()));
glm::dmat4 dSGCTViewToWorldMatrix = glm::inverse(
renderData.camera.combinedViewMatrix()
);
// Eye Space in SGCT to OS World Space
program.setUniform(_uniformCache2.dSGCTViewToWorldMatrix,
dSGCTViewToWorldMatrix);
// SGCT Projection to SGCT Eye Space
glm::dmat4 dInverseProjection = glm::inverse(
glm::dmat4(renderData.camera.projectionMatrix()));
// SGCT Projection to OS Camera Before Rotation
glm::dmat4 dProjectionToTmpRotTransformMatrix =
glm::mat4_cast(
static_cast<glm::dquat>(renderData.camera.rotationQuaternion())
) *
dSgctEye2OSEye *
glm::inverse(renderData.camera.viewScaleMatrix()) *
dInverseProjection;
// SGCT Projection to World Space
glm::dmat4 dSgctProjectionToWorldTransformMatrix(
dProjectionToTmpRotTransformMatrix
);
double* mSource = glm::value_ptr(dSgctProjectionToWorldTransformMatrix);
mSource[12] += renderData.camera.eyePositionVec3().x;
mSource[13] += renderData.camera.eyePositionVec3().y;
mSource[14] += renderData.camera.eyePositionVec3().z;
mSource[15] = 1.0;
// SGCT Projection to Object Space
glm::dmat4 inverseWholeMatrixPipeline = inverseModelMatrix *
dSgctProjectionToWorldTransformMatrix;
program.setUniform(_uniformCache2.dSgctProjectionToModelTransformMatrix,
inverseWholeMatrixPipeline);
glm::dvec4 camPosObjCoords = inverseModelMatrix *
glm::dvec4(renderData.camera.eyePositionVec3(), 1.0);
program.setUniform(_uniformCache2.dCamPosObj, camPosObjCoords);
double lt;
glm::dvec3 sunPosWorld = SpiceManager::ref().targetPosition(
"SUN",
"SUN",
"GALACTIC",
{},
_time,
lt
);
glm::dvec4 sunPosObj = glm::dvec4(0.0);
// Sun following camera position
if (_sunFollowingCameraEnabled) {
sunPosObj = inverseModelMatrix * glm::dvec4(
renderData.camera.eyePositionVec3(),
1.0
);
}
else {
sunPosObj = inverseModelMatrix *
glm::dvec4(sunPosWorld - renderData.modelTransform.translation, 1.0);
}
// Sun Position in Object Space
program.setUniform(
_uniformCache2.sunDirectionObj,
glm::normalize(glm::dvec3(sunPosObj))
);
// Shadow calculations..
if (!_shadowConfArray.empty()) {
std::vector<ShadowRenderingStruct> shadowDataArray;
shadowDataArray.reserve(_shadowConfArray.size());
for (const ShadowConfiguration & shadowConf : _shadowConfArray) {
// TO REMEMBER: all distances and lengths in world coordinates are in
// meters!!! We need to move this to view space...
// Getting source and caster:
glm::dvec3 sourcePos = SpiceManager::ref().targetPosition(
shadowConf.source.first,
"SUN", "GALACTIC",
{},
_time,
lt
);
sourcePos *= KM_TO_M; // converting to meters
glm::dvec3 casterPos = SpiceManager::ref().targetPosition(
shadowConf.caster.first,
"SUN", "GALACTIC",
{},
_time,
lt
);
casterPos *= KM_TO_M; // converting to meters
// First we determine if the caster is shadowing the current planet
// (all calculations in World Coordinates):
glm::dvec3 planetCasterVec = casterPos - renderData.position.dvec3();
glm::dvec3 sourceCasterVec = casterPos - sourcePos;
double sc_length = glm::length(sourceCasterVec);
glm::dvec3 planetCaster_proj = (
glm::dot(planetCasterVec, sourceCasterVec) /
(sc_length*sc_length)) * sourceCasterVec;
double d_test = glm::length(planetCasterVec - planetCaster_proj);
double xp_test = shadowConf.caster.second *
sc_length / (shadowConf.source.second + shadowConf.caster.second);
double rp_test = shadowConf.caster.second *
(glm::length(planetCaster_proj) + xp_test) / xp_test;
double casterDistSun = glm::length(casterPos - sunPosWorld);
double planetDistSun = glm::length(
renderData.position.dvec3() - sunPosWorld
);
ShadowRenderingStruct shadowData;
shadowData.isShadowing = false;
if (((d_test - rp_test) < (_atmospherePlanetRadius * KM_TO_M)) &&
//if (((d_test - rp_test) < (_atmosphereRadius * KM_TO_M)) &&
(casterDistSun < planetDistSun)) {
// The current caster is shadowing the current planet
shadowData.isShadowing = true;
shadowData.rs = shadowConf.source.second;
shadowData.rc = shadowConf.caster.second;
shadowData.sourceCasterVec = glm::normalize(sourceCasterVec);
shadowData.xp = xp_test;
shadowData.xu = shadowData.rc * sc_length /
(shadowData.rs - shadowData.rc);
shadowData.casterPositionVec = casterPos;
}
shadowDataArray.push_back(shadowData);
}
const std::string uniformVarName("shadowDataArray[");
unsigned int counter = 0;
for (const ShadowRenderingStruct & sd : shadowDataArray) {
std::stringstream ss;
ss << uniformVarName << counter << "].isShadowing";
program.setUniform(ss.str(), sd.isShadowing);
if (sd.isShadowing) {
ss.str(std::string());
ss << uniformVarName << counter << "].xp";
program.setUniform(ss.str(), sd.xp);
ss.str(std::string());
ss << uniformVarName << counter << "].xu";
program.setUniform(ss.str(), sd.xu);
// ss.str(std::string());
// ss << uniformVarName << counter << "].rs";
// program.setUniform(ss.str(), sd.rs);
ss.str(std::string());
ss << uniformVarName << counter << "].rc";
program.setUniform(ss.str(), sd.rc);
ss.str(std::string());
ss << uniformVarName << counter << "].sourceCasterVec";
program.setUniform(ss.str(), sd.sourceCasterVec);
ss.str(std::string());
ss << uniformVarName << counter << "].casterPositionVec";
program.setUniform(ss.str(), sd.casterPositionVec);
}
counter++;
}
program.setUniform(_uniformCache2.hardShadows, _hardShadowsEnabled);
}
}
}
_transmittanceTableTextureUnit.activate();
glBindTexture(GL_TEXTURE_2D, _transmittanceTableTexture);
program.setUniform(
_uniformCache2.transmittanceTexture,
_transmittanceTableTextureUnit
);
_irradianceTableTextureUnit.activate();
glBindTexture(GL_TEXTURE_2D, _irradianceTableTexture);
program.setUniform(_uniformCache2.irradianceTexture, _irradianceTableTextureUnit);
_inScatteringTableTextureUnit.activate();
glBindTexture(GL_TEXTURE_3D, _inScatteringTableTexture);
program.setUniform(_uniformCache2.inscatterTexture, _inScatteringTableTextureUnit);
}
void AtmosphereDeferredcaster::postRaycast(const RenderData&,
const DeferredcastData&,
ghoul::opengl::ProgramObject&)
{
// Deactivate the texture units
_transmittanceTableTextureUnit.deactivate();
_irradianceTableTextureUnit.deactivate();
_inScatteringTableTextureUnit.deactivate();
}
std::string AtmosphereDeferredcaster::deferredcastPath() const {
return GlslDeferredcastPath;
}
std::string AtmosphereDeferredcaster::deferredcastFSPath() const {
return GlslDeferredcastFSPath;
}
std::string AtmosphereDeferredcaster::deferredcastVSPath() const {
return GlslDeferredcastVsPath;
}
std::string AtmosphereDeferredcaster::helperPath() const {
return ""; // no helper file
}
void AtmosphereDeferredcaster::initializeCachedVariables(
ghoul::opengl::ProgramObject& program)
{
_uniformCache.cullAtmosphere = program.uniformLocation("cullAtmosphere");
_uniformCache.Rg = program.uniformLocation("Rg");
_uniformCache.Rt = program.uniformLocation("Rt");
_uniformCache.groundRadianceEmittion = program.uniformLocation(
"groundRadianceEmittion"
);
_uniformCache.HR = program.uniformLocation("HR");
_uniformCache.betaRayleigh = program.uniformLocation("betaRayleigh");
_uniformCache.HM = program.uniformLocation("HM");
_uniformCache.betaMieExtinction = program.uniformLocation("betaMieExtinction");
_uniformCache.mieG = program.uniformLocation("mieG");
_uniformCache.sunRadiance = program.uniformLocation("sunRadiance");
_uniformCache.ozoneLayerEnabled = program.uniformLocation("ozoneLayerEnabled");
_uniformCache.HO = program.uniformLocation("HO");
_uniformCache.betaOzoneExtinction = program.uniformLocation("betaOzoneExtinction");
_uniformCache.SAMPLES_R = program.uniformLocation("SAMPLES_R");
_uniformCache.SAMPLES_MU = program.uniformLocation("SAMPLES_MU");
_uniformCache.SAMPLES_MU_S = program.uniformLocation("SAMPLES_MU_S");
_uniformCache.SAMPLES_NU = program.uniformLocation("SAMPLES_NU");
_uniformCache2.dInverseModelTransformMatrix = program.uniformLocation(
"dInverseModelTransformMatrix"
);
_uniformCache2.dModelTransformMatrix = program.uniformLocation(
"dModelTransformMatrix"
);
_uniformCache2.dSgctProjectionToModelTransformMatrix = program.uniformLocation(
"dSgctProjectionToModelTransformMatrix"
);
_uniformCache2.dSGCTViewToWorldMatrix = program.uniformLocation(
"dSGCTViewToWorldMatrix"
);
_uniformCache2.dCamPosObj = program.uniformLocation("dCamPosObj");
_uniformCache2.sunDirectionObj = program.uniformLocation("sunDirectionObj");
_uniformCache2.hardShadows = program.uniformLocation("hardShadows");
_uniformCache2.transmittanceTexture = program.uniformLocation("transmittanceTexture");
_uniformCache2.irradianceTexture = program.uniformLocation("irradianceTexture");
_uniformCache2.inscatterTexture = program.uniformLocation("inscatterTexture");
}
void AtmosphereDeferredcaster::update(const UpdateData&) {
}
void AtmosphereDeferredcaster::setModelTransform(const glm::dmat4& transform) {
_modelTransform = transform;
}
void AtmosphereDeferredcaster::setTime(double time) {
_time = time;
}
void AtmosphereDeferredcaster::setAtmosphereRadius(float atmRadius) {
_atmosphereRadius = atmRadius;
}
void AtmosphereDeferredcaster::setPlanetRadius(float planetRadius) {
_atmospherePlanetRadius = planetRadius;
}
void AtmosphereDeferredcaster::setPlanetAverageGroundReflectance(
float averageGReflectance)
{
_planetAverageGroundReflectance = averageGReflectance;
}
void AtmosphereDeferredcaster::setPlanetGroundRadianceEmittion(
float groundRadianceEmittion)
{
_planetGroundRadianceEmittion = groundRadianceEmittion;
}
void AtmosphereDeferredcaster::setRayleighHeightScale(float rayleighHeightScale) {
_rayleighHeightScale = rayleighHeightScale;
}
void AtmosphereDeferredcaster::enableOzone(bool enable) {
_ozoneEnabled = enable;
}
void AtmosphereDeferredcaster::setOzoneHeightScale(float ozoneHeightScale) {
_ozoneHeightScale = ozoneHeightScale;
}
void AtmosphereDeferredcaster::setMieHeightScale(float mieHeightScale) {
_mieHeightScale = mieHeightScale;
}
void AtmosphereDeferredcaster::setMiePhaseConstant(float miePhaseConstant) {
_miePhaseConstant = miePhaseConstant;
}
void AtmosphereDeferredcaster::setSunRadianceIntensity(float sunRadiance) {
_sunRadianceIntensity = sunRadiance;
}
void AtmosphereDeferredcaster::setRayleighScatteringCoefficients(
const glm::vec3& rayScattCoeff)
{
_rayleighScatteringCoeff = std::move(rayScattCoeff);
}
void AtmosphereDeferredcaster::setOzoneExtinctionCoefficients(
const glm::vec3& ozoneExtCoeff)
{
_ozoneExtinctionCoeff = std::move(ozoneExtCoeff);
}
void AtmosphereDeferredcaster::setMieScatteringCoefficients(
const glm::vec3& mieScattCoeff)
{
_mieScatteringCoeff = std::move(mieScattCoeff);
}
void AtmosphereDeferredcaster::setMieExtinctionCoefficients(const glm::vec3& mieExtCoeff)
{
_mieExtinctionCoeff = std::move(mieExtCoeff);
}
void AtmosphereDeferredcaster::setEllipsoidRadii(const glm::dvec3& radii) {
_ellipsoidRadii = std::move(radii);
}
void AtmosphereDeferredcaster::setHardShadows(bool enabled) {
_hardShadowsEnabled = enabled;
}
void AtmosphereDeferredcaster::setShadowConfigArray(
const std::vector<ShadowConfiguration>& shadowConfigArray)
{
_shadowConfArray = std::move(shadowConfigArray);
}
void AtmosphereDeferredcaster::enableSunFollowing(bool enable) {
_sunFollowingCameraEnabled = enable;
}
void AtmosphereDeferredcaster::setPrecalculationTextureScale(
float preCalculatedTexturesScale)
{
_calculationTextureScale = preCalculatedTexturesScale;
_transmittance_table_width *= static_cast<unsigned int>(_calculationTextureScale);
_transmittance_table_height *= static_cast<unsigned int>(_calculationTextureScale);
_irradiance_table_width *= static_cast<unsigned int>(_calculationTextureScale);
_irradiance_table_height *= static_cast<unsigned int>(_calculationTextureScale);
_delta_e_table_width *= static_cast<unsigned int>(_calculationTextureScale);
_delta_e_table_height *= static_cast<unsigned int>(_calculationTextureScale);
_r_samples *= static_cast<unsigned int>(_calculationTextureScale);
_mu_samples *= static_cast<unsigned int>(_calculationTextureScale);
_mu_s_samples *= static_cast<unsigned int>(_calculationTextureScale);
_nu_samples *= static_cast<unsigned int>(_calculationTextureScale);
}
void AtmosphereDeferredcaster::enablePrecalculationTexturesSaving() {
_saveCalculationTextures = true;
}
void AtmosphereDeferredcaster::loadComputationPrograms() {
//============== Transmittance T =================
if (!_transmittanceProgramObject) {
_transmittanceProgramObject = ghoul::opengl::ProgramObject::Build(
"transmittanceCalcProgram",
absPath("${MODULE_ATMOSPHERE}/shaders/transmittance_calc_vs.glsl"),
absPath("${MODULE_ATMOSPHERE}/shaders/transmittance_calc_fs.glsl")
);
}
using IgnoreError = ghoul::opengl::ProgramObject::IgnoreError;
_transmittanceProgramObject->setIgnoreSubroutineUniformLocationError(
IgnoreError::Yes
);
_transmittanceProgramObject->setIgnoreUniformLocationError(IgnoreError::Yes);
//============== Irradiance E =================
if (!_irradianceProgramObject) {
_irradianceProgramObject = ghoul::opengl::ProgramObject::Build(
"irradianceCalcProgram",
absPath("${MODULE_ATMOSPHERE}/shaders/irradiance_calc_vs.glsl"),
absPath("${MODULE_ATMOSPHERE}/shaders/irradiance_calc_fs.glsl"));
}
_irradianceProgramObject->setIgnoreSubroutineUniformLocationError(IgnoreError::Yes);
_irradianceProgramObject->setIgnoreUniformLocationError(IgnoreError::Yes);
if (!_irradianceSupTermsProgramObject) {
_irradianceSupTermsProgramObject = ghoul::opengl::ProgramObject::Build(
"irradianceSupTermsCalcProgram",
absPath("${MODULE_ATMOSPHERE}/shaders/irradiance_sup_calc_vs.glsl"),
absPath("${MODULE_ATMOSPHERE}/shaders/irradiance_sup_calc_fs.glsl"));
}
_irradianceSupTermsProgramObject->setIgnoreSubroutineUniformLocationError(
IgnoreError::Yes
);
_irradianceSupTermsProgramObject->setIgnoreUniformLocationError(IgnoreError::Yes);
//============== InScattering S =================
if (!_inScatteringProgramObject) {
_inScatteringProgramObject = ghoul::opengl::ProgramObject::Build(
"inScatteringCalcProgram",
absPath("${MODULE_ATMOSPHERE}/shaders/inScattering_calc_vs.glsl"),
absPath("${MODULE_ATMOSPHERE}/shaders/inScattering_calc_fs.glsl"),
absPath("${MODULE_ATMOSPHERE}/shaders/inScattering_calc_gs.glsl"));
}
_inScatteringProgramObject->setIgnoreSubroutineUniformLocationError(IgnoreError::Yes);
_inScatteringProgramObject->setIgnoreUniformLocationError(IgnoreError::Yes);
if (!_inScatteringSupTermsProgramObject) {
_inScatteringSupTermsProgramObject = ghoul::opengl::ProgramObject::Build(
"inScatteringSupTermsCalcProgram",
absPath("${MODULE_ATMOSPHERE}/shaders/inScattering_sup_calc_vs.glsl"),
absPath("${MODULE_ATMOSPHERE}/shaders/inScattering_sup_calc_fs.glsl"),
absPath("${MODULE_ATMOSPHERE}/shaders/inScattering_sup_calc_gs.glsl"));
}
_inScatteringSupTermsProgramObject->setIgnoreSubroutineUniformLocationError(
IgnoreError::Yes
);
_inScatteringSupTermsProgramObject->setIgnoreUniformLocationError(IgnoreError::Yes);
//============== Delta E =================
if (!_deltaEProgramObject) {
_deltaEProgramObject = ghoul::opengl::ProgramObject::Build(
"deltaECalcProgram",
absPath("${MODULE_ATMOSPHERE}/shaders/deltaE_calc_vs.glsl"),
absPath("${MODULE_ATMOSPHERE}/shaders/deltaE_calc_fs.glsl"));
}
_deltaEProgramObject->setIgnoreSubroutineUniformLocationError(IgnoreError::Yes);
_deltaEProgramObject->setIgnoreUniformLocationError(IgnoreError::Yes);
//============== Irradiance finel E =================
if (!_irradianceFinalProgramObject) {
_irradianceFinalProgramObject = ghoul::opengl::ProgramObject::Build(
"irradianceEFinalProgram",
absPath("${MODULE_ATMOSPHERE}/shaders/irradiance_final_vs.glsl"),
absPath("${MODULE_ATMOSPHERE}/shaders/irradiance_final_fs.glsl"));
}
_irradianceFinalProgramObject->setIgnoreSubroutineUniformLocationError(
IgnoreError::Yes
);
_irradianceFinalProgramObject->setIgnoreUniformLocationError(IgnoreError::Yes);
//============== Delta S =================
if (!_deltaSProgramObject) {
_deltaSProgramObject = ghoul::opengl::ProgramObject::Build(
"deltaSCalcProgram",
absPath("${MODULE_ATMOSPHERE}/shaders/deltaS_calc_vs.glsl"),
absPath("${MODULE_ATMOSPHERE}/shaders/deltaS_calc_fs.glsl"),
absPath("${MODULE_ATMOSPHERE}/shaders/deltaS_calc_gs.glsl"));
}
_deltaSProgramObject->setIgnoreSubroutineUniformLocationError(IgnoreError::Yes);
_deltaSProgramObject->setIgnoreUniformLocationError(IgnoreError::Yes);
if (!_deltaSSupTermsProgramObject) {
_deltaSSupTermsProgramObject = ghoul::opengl::ProgramObject::Build(
"deltaSSUPTermsCalcProgram",
absPath("${MODULE_ATMOSPHERE}/shaders/deltaS_sup_calc_vs.glsl"),
absPath("${MODULE_ATMOSPHERE}/shaders/deltaS_sup_calc_fs.glsl"),
absPath("${MODULE_ATMOSPHERE}/shaders/deltaS_sup_calc_gs.glsl"));
}
_deltaSSupTermsProgramObject->setIgnoreSubroutineUniformLocationError(
IgnoreError::Yes
);
_deltaSSupTermsProgramObject->setIgnoreUniformLocationError(IgnoreError::Yes);
//============== Delta J (Radiance Scattered) =================
if (!_deltaJProgramObject) {
_deltaJProgramObject = ghoul::opengl::ProgramObject::Build(
"deltaJCalcProgram",
absPath("${MODULE_ATMOSPHERE}/shaders/deltaJ_calc_vs.glsl"),
absPath("${MODULE_ATMOSPHERE}/shaders/deltaJ_calc_fs.glsl"),
absPath("${MODULE_ATMOSPHERE}/shaders/deltaJ_calc_gs.glsl"));
}
_deltaJProgramObject->setIgnoreSubroutineUniformLocationError(IgnoreError::Yes);
_deltaJProgramObject->setIgnoreUniformLocationError(IgnoreError::Yes);
}
void AtmosphereDeferredcaster::unloadComputationPrograms() {
_transmittanceProgramObject = nullptr;
_irradianceProgramObject = nullptr;
_irradianceSupTermsProgramObject = nullptr;
_inScatteringProgramObject = nullptr;
_inScatteringSupTermsProgramObject = nullptr;
_deltaEProgramObject = nullptr;
_irradianceFinalProgramObject = nullptr;
_deltaSProgramObject = nullptr;
_deltaSSupTermsProgramObject = nullptr;
_deltaJProgramObject = nullptr;
}
void AtmosphereDeferredcaster::createComputationTextures() {
if (!_atmosphereCalculated) {
//============== Transmittance =================
ghoul::opengl::TextureUnit transmittanceTableTextureUnit;
transmittanceTableTextureUnit.activate();
glGenTextures(1, &_transmittanceTableTexture);
glBindTexture(GL_TEXTURE_2D, _transmittanceTableTexture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
// Stopped using a buffer object for GL_PIXEL_UNPACK_BUFFER
glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB32F, _transmittance_table_width,
_transmittance_table_height, 0, GL_RGB, GL_FLOAT, nullptr);
//============== Irradiance =================
ghoul::opengl::TextureUnit irradianceTableTextureUnit;
irradianceTableTextureUnit.activate();
glGenTextures(1, &_irradianceTableTexture);
glBindTexture(GL_TEXTURE_2D, _irradianceTableTexture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB32F, _irradiance_table_width,
_irradiance_table_height, 0, GL_RGB, GL_FLOAT, nullptr);
//============== InScattering =================
ghoul::opengl::TextureUnit inScatteringTableTextureUnit;
inScatteringTableTextureUnit.activate();
glGenTextures(1, &_inScatteringTableTexture);
glBindTexture(GL_TEXTURE_3D, _inScatteringTableTexture);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
glTexImage3D(GL_TEXTURE_3D, 0, GL_RGBA32F, _mu_s_samples * _nu_samples,
_mu_samples, _r_samples, 0, GL_RGB, GL_FLOAT, nullptr);
}
//============== Delta E =================
ghoul::opengl::TextureUnit deltaETableTextureUnit;
deltaETableTextureUnit.activate();
glGenTextures(1, &_deltaETableTexture);
glBindTexture(GL_TEXTURE_2D, _deltaETableTexture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB32F, _delta_e_table_width,
_delta_e_table_height, 0, GL_RGB, GL_FLOAT, nullptr);
//============== Delta S =================
ghoul::opengl::TextureUnit deltaSRayleighTableTextureUnit;
deltaSRayleighTableTextureUnit.activate();
glGenTextures(1, &_deltaSRayleighTableTexture);
glBindTexture(GL_TEXTURE_3D, _deltaSRayleighTableTexture);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
glTexImage3D(GL_TEXTURE_3D, 0, GL_RGB32F, _mu_s_samples * _nu_samples,
_mu_samples, _r_samples, 0, GL_RGB, GL_FLOAT, nullptr);
ghoul::opengl::TextureUnit deltaSMieTableTextureUnit;
deltaSMieTableTextureUnit.activate();
glGenTextures(1, &_deltaSMieTableTexture);
glBindTexture(GL_TEXTURE_3D, _deltaSMieTableTexture);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
glTexImage3D(GL_TEXTURE_3D, 0, GL_RGB32F, _mu_s_samples * _nu_samples,
_mu_samples, _r_samples, 0, GL_RGB, GL_FLOAT, nullptr);
//============== Delta J (Radiance Scattered) =================
ghoul::opengl::TextureUnit deltaJTableTextureUnit;
deltaJTableTextureUnit.activate();
glGenTextures(1, &_deltaJTableTexture);
glBindTexture(GL_TEXTURE_3D, _deltaJTableTexture);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
glTexImage3D(GL_TEXTURE_3D, 0, GL_RGB32F, _mu_s_samples * _nu_samples,
_mu_samples, _r_samples, 0, GL_RGB, GL_FLOAT, nullptr);
}
void AtmosphereDeferredcaster::deleteComputationTextures() {
// Cleaning up
glDeleteTextures(1, &_transmittanceTableTexture);
glDeleteTextures(1, &_irradianceTableTexture);
glDeleteTextures(1, &_inScatteringTableTexture);
glDeleteTextures(1, &_deltaETableTexture);
glDeleteTextures(1, &_deltaSRayleighTableTexture);
glDeleteTextures(1, &_deltaSMieTableTexture);
glDeleteTextures(1, &_deltaJTableTexture);
}
void AtmosphereDeferredcaster::deleteUnusedComputationTextures() {
glDeleteTextures(1, &_deltaETableTexture);
glDeleteTextures(1, &_deltaSRayleighTableTexture);
glDeleteTextures(1, &_deltaSMieTableTexture);
glDeleteTextures(1, &_deltaJTableTexture);
}
void AtmosphereDeferredcaster::executeCalculations(GLuint quadCalcVAO,
GLenum drawBuffers[1],
GLsizei vertexSize)
{
ghoul::opengl::TextureUnit transmittanceTableTextureUnit;
ghoul::opengl::TextureUnit irradianceTableTextureUnit;
ghoul::opengl::TextureUnit inScatteringTableTextureUnit;
ghoul::opengl::TextureUnit deltaETableTextureUnit;
ghoul::opengl::TextureUnit deltaSRayleighTableTextureUnit;
ghoul::opengl::TextureUnit deltaSMieTableTextureUnit;
ghoul::opengl::TextureUnit deltaJTableTextureUnit;
// Saving current OpenGL state
GLboolean blendEnabled = glIsEnabled(GL_BLEND);
GLenum blendEquationRGB;
GLenum blendEquationAlpha;
GLenum blendDestAlpha;
GLenum blendDestRGB;
GLenum blendSrcAlpha;
GLenum blendSrcRGB;
if (blendEnabled) {
glDisable(GL_BLEND);
}
glGetIntegerv(GL_BLEND_EQUATION_RGB, &blendEquationRGB);
glGetIntegerv(GL_BLEND_EQUATION_ALPHA, &blendEquationAlpha);
glGetIntegerv(GL_BLEND_DST_ALPHA, &blendDestAlpha);
glGetIntegerv(GL_BLEND_DST_RGB, &blendDestRGB);
glGetIntegerv(GL_BLEND_SRC_ALPHA, &blendSrcAlpha);
glGetIntegerv(GL_BLEND_SRC_RGB, &blendSrcRGB);
// ===========================================================
// See Precomputed Atmosphere Scattering from Bruneton et al. paper, algorithm 4.1:
// ===========================================================
glFramebufferTexture(
GL_FRAMEBUFFER,
GL_COLOR_ATTACHMENT0,
_transmittanceTableTexture,
0
);
checkFrameBufferState("_transmittanceTableTexture");
glViewport(0, 0, _transmittance_table_width, _transmittance_table_height);
_transmittanceProgramObject->activate();
loadAtmosphereDataIntoShaderProgram(_transmittanceProgramObject);
//glClear(GL_COLOR_BUFFER_BIT);
static const float black[] = { 0.0f, 0.0f, 0.0f, 0.0f };
glClearBufferfv(GL_COLOR, 0, black);
renderQuadForCalc(quadCalcVAO, vertexSize);
if (_saveCalculationTextures) {
saveTextureToPPMFile(
GL_COLOR_ATTACHMENT0,
std::string("transmittance_texture.ppm"),
_transmittance_table_width,
_transmittance_table_height
);
}
_transmittanceProgramObject->deactivate();
// line 2 in algorithm 4.1
glFramebufferTexture(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, _deltaETableTexture, 0);
checkFrameBufferState("_deltaETableTexture");
glViewport(0, 0, _delta_e_table_width, _delta_e_table_height);
_irradianceProgramObject->activate();
transmittanceTableTextureUnit.activate();
glBindTexture(GL_TEXTURE_2D, _transmittanceTableTexture);
_irradianceProgramObject->setUniform(
"transmittanceTexture",
transmittanceTableTextureUnit
);
loadAtmosphereDataIntoShaderProgram(_irradianceProgramObject);
glClear(GL_COLOR_BUFFER_BIT);
renderQuadForCalc(quadCalcVAO, vertexSize);
if (_saveCalculationTextures) {
saveTextureToPPMFile(
GL_COLOR_ATTACHMENT0,
std::string("deltaE_table_texture.ppm"),
_delta_e_table_width,
_delta_e_table_height
);
}
_irradianceProgramObject->deactivate();
// line 3 in algorithm 4.1
glFramebufferTexture(
GL_FRAMEBUFFER,
GL_COLOR_ATTACHMENT0,
_deltaSRayleighTableTexture,
0
);
glFramebufferTexture(
GL_FRAMEBUFFER,
GL_COLOR_ATTACHMENT1,
_deltaSMieTableTexture,
0
);
GLenum colorBuffers[2] = { GL_COLOR_ATTACHMENT0, GL_COLOR_ATTACHMENT1 };
glDrawBuffers(2, colorBuffers);
checkFrameBufferState("_deltaSRay and _deltaSMie TableTexture");
glViewport(0, 0, _mu_s_samples * _nu_samples, _mu_samples);
_inScatteringProgramObject->activate();
transmittanceTableTextureUnit.activate();
glBindTexture(GL_TEXTURE_2D, _transmittanceTableTexture);
_inScatteringProgramObject->setUniform(
"transmittanceTexture",
transmittanceTableTextureUnit
);
loadAtmosphereDataIntoShaderProgram(_inScatteringProgramObject);
glClear(GL_COLOR_BUFFER_BIT);
for (int layer = 0; layer < _r_samples; ++layer) {
step3DTexture(_inScatteringProgramObject, layer);
renderQuadForCalc(quadCalcVAO, vertexSize);
}
if (_saveCalculationTextures) {
saveTextureToPPMFile(
GL_COLOR_ATTACHMENT0,
std::string("deltaS_rayleigh_texture.ppm"),
_mu_s_samples * _nu_samples,
_mu_samples
);
saveTextureToPPMFile(
GL_COLOR_ATTACHMENT1,
std::string("deltaS_mie_texture.ppm"),
_mu_s_samples * _nu_samples,
_mu_samples
);
}
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT1, GL_TEXTURE_2D, 0, 0);
glDrawBuffers(1, drawBuffers);
_inScatteringProgramObject->deactivate();
// line 4 in algorithm 4.1
glFramebufferTexture(
GL_FRAMEBUFFER,
GL_COLOR_ATTACHMENT0,
_irradianceTableTexture,
0
);
checkFrameBufferState("_irradianceTableTexture");
glDrawBuffer(GL_COLOR_ATTACHMENT0);
glViewport(0, 0, _delta_e_table_width, _delta_e_table_height);
_deltaEProgramObject->activate();
//_deltaEProgramObject->setUniform("line", 4);
deltaETableTextureUnit.activate();
glBindTexture(GL_TEXTURE_2D, _deltaETableTexture);
_deltaEProgramObject->setUniform("deltaETexture", deltaETableTextureUnit);
loadAtmosphereDataIntoShaderProgram(_deltaEProgramObject);
glClear(GL_COLOR_BUFFER_BIT);
renderQuadForCalc(quadCalcVAO, vertexSize);
if (_saveCalculationTextures) {
saveTextureToPPMFile(GL_COLOR_ATTACHMENT0, std::string("irradiance_texture.ppm"),
_delta_e_table_width, _delta_e_table_height);
}
_deltaEProgramObject->deactivate();
// line 5 in algorithm 4.1
glFramebufferTexture(
GL_FRAMEBUFFER,
GL_COLOR_ATTACHMENT0,
_inScatteringTableTexture,
0
);
checkFrameBufferState("_inScatteringTableTexture");
glViewport(0, 0, _mu_s_samples * _nu_samples, _mu_samples);
_deltaSProgramObject->activate();
deltaSRayleighTableTextureUnit.activate();
glBindTexture(GL_TEXTURE_3D, _deltaSRayleighTableTexture);
deltaSMieTableTextureUnit.activate();
glBindTexture(GL_TEXTURE_3D, _deltaSMieTableTexture);
_deltaSProgramObject->setUniform("deltaSRTexture", deltaSRayleighTableTextureUnit);
_deltaSProgramObject->setUniform("deltaSMTexture", deltaSMieTableTextureUnit);
loadAtmosphereDataIntoShaderProgram(_deltaSProgramObject);
glClear(GL_COLOR_BUFFER_BIT);
for (int layer = 0; layer < _r_samples; ++layer) {
step3DTexture(_deltaSProgramObject, layer, false);
renderQuadForCalc(quadCalcVAO, vertexSize);
}
if (_saveCalculationTextures) {
saveTextureToPPMFile(GL_COLOR_ATTACHMENT0, std::string("S_texture.ppm"),
_mu_s_samples * _nu_samples, _mu_samples);
}
_deltaSProgramObject->deactivate();
// loop in line 6 in algorithm 4.1
for (int scatteringOrder = 2; scatteringOrder <= 4; ++scatteringOrder) {
// line 7 in algorithm 4.1
glFramebufferTexture(
GL_FRAMEBUFFER,
GL_COLOR_ATTACHMENT0,
_deltaJTableTexture,
0
);
checkFrameBufferState("_deltaJTableTexture");
glViewport(0, 0, _mu_s_samples * _nu_samples, _mu_samples);
_deltaJProgramObject->activate();
if (scatteringOrder == 2) {
_deltaJProgramObject->setUniform("firstIteraction", 1);
}
else {
_deltaJProgramObject->setUniform("firstIteraction", 0);
}
transmittanceTableTextureUnit.activate();
glBindTexture(GL_TEXTURE_2D, _transmittanceTableTexture);
_deltaJProgramObject->setUniform(
"transmittanceTexture",
transmittanceTableTextureUnit
);
deltaETableTextureUnit.activate();
glBindTexture(GL_TEXTURE_2D, _deltaETableTexture);
_deltaJProgramObject->setUniform("deltaETexture", deltaETableTextureUnit);
deltaSRayleighTableTextureUnit.activate();
glBindTexture(GL_TEXTURE_3D, _deltaSRayleighTableTexture);
_deltaJProgramObject->setUniform(
"deltaSRTexture",
deltaSRayleighTableTextureUnit
);
deltaSMieTableTextureUnit.activate();
glBindTexture(GL_TEXTURE_3D, _deltaSMieTableTexture);
_deltaJProgramObject->setUniform("deltaSMTexture", deltaSMieTableTextureUnit);
loadAtmosphereDataIntoShaderProgram(_deltaJProgramObject);
for (int layer = 0; layer < _r_samples; ++layer) {
step3DTexture(_deltaJProgramObject, layer);
renderQuadForCalc(quadCalcVAO, vertexSize);
}
if (_saveCalculationTextures) {
saveTextureToPPMFile(GL_COLOR_ATTACHMENT0,
fmt::format("deltaJ_texture-scattering_order-{}.ppm", scatteringOrder),
_mu_s_samples * _nu_samples, _mu_samples);
}
_deltaJProgramObject->deactivate();
// line 8 in algorithm 4.1
glFramebufferTexture(
GL_FRAMEBUFFER,
GL_COLOR_ATTACHMENT0,
_deltaETableTexture,
0
);
checkFrameBufferState("_deltaETableTexture");
glViewport(0, 0, _delta_e_table_width, _delta_e_table_height);
_irradianceSupTermsProgramObject->activate();
if (scatteringOrder == 2) {
_irradianceSupTermsProgramObject->setUniform("firstIteraction", 1);
}
else {
_irradianceSupTermsProgramObject->setUniform("firstIteraction", 0);
}
transmittanceTableTextureUnit.activate();
glBindTexture(GL_TEXTURE_2D, _transmittanceTableTexture);
_irradianceSupTermsProgramObject->setUniform(
"transmittanceTexture",
transmittanceTableTextureUnit
);
deltaSRayleighTableTextureUnit.activate();
glBindTexture(GL_TEXTURE_3D, _deltaSRayleighTableTexture);
_irradianceSupTermsProgramObject->setUniform(
"deltaSRTexture",
deltaSRayleighTableTextureUnit
);
deltaSMieTableTextureUnit.activate();
glBindTexture(GL_TEXTURE_3D, _deltaSMieTableTexture);
_irradianceSupTermsProgramObject->setUniform(
"deltaSMTexture",
deltaSMieTableTextureUnit
);
loadAtmosphereDataIntoShaderProgram(_irradianceSupTermsProgramObject);
renderQuadForCalc(quadCalcVAO, vertexSize);
if (_saveCalculationTextures) {
saveTextureToPPMFile(GL_COLOR_ATTACHMENT0,
fmt::format("deltaE_texture-scattering_order-{}.ppm", scatteringOrder),
_delta_e_table_width, _delta_e_table_height);
}
_irradianceSupTermsProgramObject->deactivate();
// line 9 in algorithm 4.1
glFramebufferTexture(
GL_FRAMEBUFFER,
GL_COLOR_ATTACHMENT0,
_deltaSRayleighTableTexture,
0
);
checkFrameBufferState("_deltaSRayleighTableTexture");
glViewport(0, 0, _mu_s_samples * _nu_samples, _mu_samples);
_inScatteringSupTermsProgramObject->activate();
transmittanceTableTextureUnit.activate();
glBindTexture(GL_TEXTURE_2D, _transmittanceTableTexture);
_inScatteringSupTermsProgramObject->setUniform(
"transmittanceTexture",
transmittanceTableTextureUnit
);
deltaJTableTextureUnit.activate();
glBindTexture(GL_TEXTURE_3D, _deltaJTableTexture);
_inScatteringSupTermsProgramObject->setUniform(
"deltaJTexture",
deltaJTableTextureUnit
);
loadAtmosphereDataIntoShaderProgram(_inScatteringSupTermsProgramObject);
for (int layer = 0; layer < _r_samples; ++layer) {
step3DTexture(_inScatteringSupTermsProgramObject, layer);
renderQuadForCalc(quadCalcVAO, vertexSize);
}
if (_saveCalculationTextures) {
saveTextureToPPMFile(GL_COLOR_ATTACHMENT0,
fmt::format("deltaS_texture-scattering_order-{}.ppm",
scatteringOrder),
_mu_s_samples * _nu_samples,
_mu_samples
);
}
_inScatteringSupTermsProgramObject->deactivate();
glEnable(GL_BLEND);
glBlendEquationSeparate(GL_FUNC_ADD, GL_FUNC_ADD);
glBlendFuncSeparate(GL_ONE, GL_ONE, GL_ONE, GL_ONE);
// line 10 in algorithm 4.1
glFramebufferTexture(
GL_FRAMEBUFFER,
GL_COLOR_ATTACHMENT0,
_irradianceTableTexture,
0
);
checkFrameBufferState("_irradianceTableTexture");
glViewport(0, 0, _delta_e_table_width, _delta_e_table_height);
_irradianceFinalProgramObject->activate();
deltaETableTextureUnit.activate();
glBindTexture(GL_TEXTURE_2D, _deltaETableTexture);
_irradianceFinalProgramObject->setUniform(
"deltaETexture",
deltaETableTextureUnit
);
loadAtmosphereDataIntoShaderProgram(_irradianceFinalProgramObject);
renderQuadForCalc(quadCalcVAO, vertexSize);
if (_saveCalculationTextures) {
saveTextureToPPMFile(GL_COLOR_ATTACHMENT0,
fmt::format("irradianceTable_order-{}.ppm",
scatteringOrder),
_delta_e_table_width, _delta_e_table_height);
}
_irradianceFinalProgramObject->deactivate();
// line 11 in algorithm 4.1
glFramebufferTexture(
GL_FRAMEBUFFER,
GL_COLOR_ATTACHMENT0,
_inScatteringTableTexture,
0
);
checkFrameBufferState("_inScatteringTableTexture");
glViewport(0, 0, _mu_s_samples * _nu_samples, _mu_samples);
_deltaSSupTermsProgramObject->activate();
deltaSRayleighTableTextureUnit.activate();
glBindTexture(GL_TEXTURE_3D, _deltaSRayleighTableTexture);
_deltaSSupTermsProgramObject->setUniform(
"deltaSTexture",
deltaSRayleighTableTextureUnit
);
loadAtmosphereDataIntoShaderProgram(_deltaSSupTermsProgramObject);
for (int layer = 0; layer < _r_samples; ++layer) {
step3DTexture(_deltaSSupTermsProgramObject, layer, false);
renderQuadForCalc(quadCalcVAO, vertexSize);
}
if (_saveCalculationTextures) {
saveTextureToPPMFile(GL_COLOR_ATTACHMENT0,
fmt::format("inscatteringTable_order-{}.ppm",
scatteringOrder),
_mu_s_samples * _nu_samples, _mu_samples);
}
_deltaSSupTermsProgramObject->deactivate();
glDisable(GL_BLEND);
}
// Restores OpenGL blending state
if (blendEnabled)
glEnable(GL_BLEND);
glBlendEquationSeparate(blendEquationRGB, blendEquationAlpha);
glBlendFuncSeparate(blendSrcRGB, blendDestRGB, blendSrcAlpha, blendDestAlpha);
}
void AtmosphereDeferredcaster::preCalculateAtmosphereParam() {
//==========================================================
//========= Load Shader Programs for Calculations ==========
//==========================================================
loadComputationPrograms();
//==========================================================
//============ Create Textures for Calculations ============
//==========================================================
createComputationTextures();
// Saves current FBO first
GLint defaultFBO;
glGetIntegerv(GL_FRAMEBUFFER_BINDING, &defaultFBO);
GLint m_viewport[4];
glGetIntegerv(GL_VIEWPORT, m_viewport);
// Creates the FBO for the calculations
GLuint calcFBO;
glGenFramebuffers(1, &calcFBO);
glBindFramebuffer(GL_FRAMEBUFFER, calcFBO);
GLenum drawBuffers[1] = { GL_COLOR_ATTACHMENT0 };
glDrawBuffers(1, drawBuffers);
// Prepare for rendering/calculations
GLuint quadCalcVAO;
GLuint quadCalcVBO;
createRenderQuad(&quadCalcVAO, &quadCalcVBO, 1.0f);
// Starting Calculations...
LDEBUG("Starting precalculations for scattering effects...");
//==========================================================
//=================== Execute Calculations =================
//==========================================================
executeCalculations(quadCalcVAO, drawBuffers, 6);
deleteUnusedComputationTextures();
// Restores system state
glBindFramebuffer(GL_FRAMEBUFFER, defaultFBO);
glViewport(
m_viewport[0],
m_viewport[1],
m_viewport[2],
m_viewport[3]
);
glDeleteBuffers(1, &quadCalcVBO);
glDeleteVertexArrays(1, &quadCalcVAO);
glDeleteFramebuffers(1, &calcFBO);
LDEBUG("Ended precalculations for Atmosphere effects...");
}
void AtmosphereDeferredcaster::createRenderQuad(GLuint* vao, GLuint* vbo, GLfloat size) {
glGenVertexArrays(1, vao);
glGenBuffers(1, vbo);
glBindVertexArray(*vao);
glBindBuffer(GL_ARRAY_BUFFER, *vbo);
const GLfloat vertex_data[] = {
// x y z w
-size, -size, 0.0f, 1.0f,
size, size, 0.0f, 1.0f,
-size, size, 0.0f, 1.0f,
-size, -size, 0.0f, 1.0f,
size, -size, 0.0f, 1.0f,
size, size, 0.0f, 1.0f
};
glBufferData(GL_ARRAY_BUFFER, sizeof(vertex_data), vertex_data, GL_STATIC_DRAW);
glVertexAttribPointer(
0,
4,
GL_FLOAT,
GL_FALSE,
sizeof(GLfloat) * 4,
nullptr
);
glEnableVertexAttribArray(0);
glBindVertexArray(0);
}
void AtmosphereDeferredcaster::loadAtmosphereDataIntoShaderProgram(
std::unique_ptr<ghoul::opengl::ProgramObject>& shaderProg)
{
shaderProg->setUniform("Rg", _atmospherePlanetRadius);
shaderProg->setUniform("Rt", _atmosphereRadius);
shaderProg->setUniform("AverageGroundReflectance", _planetAverageGroundReflectance);
shaderProg->setUniform("groundRadianceEmittion", _planetGroundRadianceEmittion);
shaderProg->setUniform("HR", _rayleighHeightScale);
shaderProg->setUniform("betaRayleigh", _rayleighScatteringCoeff);
shaderProg->setUniform("HM", _mieHeightScale);
shaderProg->setUniform("betaMieScattering", _mieScatteringCoeff);
shaderProg->setUniform("betaMieExtinction", _mieExtinctionCoeff);
shaderProg->setUniform("mieG", _miePhaseConstant);
shaderProg->setUniform("sunRadiance", _sunRadianceIntensity);
shaderProg->setUniform("TRANSMITTANCE_W", _transmittance_table_width);
shaderProg->setUniform("TRANSMITTANCE_H", _transmittance_table_height);
shaderProg->setUniform("SKY_W", _irradiance_table_width);
shaderProg->setUniform("SKY_H", _irradiance_table_height);
shaderProg->setUniform("OTHER_TEXTURES_W", _delta_e_table_width);
shaderProg->setUniform("OTHER_TEXTURES_H", _delta_e_table_height);
shaderProg->setUniform("SAMPLES_R", _r_samples);
shaderProg->setUniform("SAMPLES_MU", _mu_samples);
shaderProg->setUniform("SAMPLES_MU_S", _mu_s_samples);
shaderProg->setUniform("SAMPLES_NU", _nu_samples);
shaderProg->setUniform("ozoneLayerEnabled", _ozoneEnabled);
shaderProg->setUniform("HO", _ozoneHeightScale);
shaderProg->setUniform("betaOzoneExtinction", _ozoneExtinctionCoeff);
}
void AtmosphereDeferredcaster::checkFrameBufferState(
const std::string& codePosition) const
{
if (glCheckFramebufferStatus(GL_DRAW_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
LERROR("Framework not built. " + codePosition);
GLenum fbErr = glCheckFramebufferStatus(GL_FRAMEBUFFER);
switch (fbErr) {
case GL_FRAMEBUFFER_UNDEFINED:
LERROR("Indefined framebuffer.");
break;
case GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT:
LERROR("Incomplete, missing attachement.");
break;
case GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT:
LERROR("Framebuffer doesn't have at least one image attached to it.");
break;
case GL_FRAMEBUFFER_INCOMPLETE_DRAW_BUFFER:
LERROR(
"Returned if the value of GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE is "
"GL_NONE for any color attachment point(s) named by GL_DRAW_BUFFERi."
);
break;
case GL_FRAMEBUFFER_INCOMPLETE_READ_BUFFER:
LERROR(
"Returned if GL_READ_BUFFER is not GL_NONE and the value of "
"GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE is GL_NONE for the color "
"attachment point named by GL_READ_BUFFER.");
break;
case GL_FRAMEBUFFER_UNSUPPORTED:
LERROR(
"Returned if the combination of internal formats of the attached "
"images violates an implementation - dependent set of restrictions."
);
break;
case GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE:
LERROR(
"Returned if the value of GL_RENDERBUFFE_r_samples is not the same "
"for all attached renderbuffers; if the value of GL_TEXTURE_SAMPLES "
"is the not same for all attached textures; or , if the attached "
"images are a mix of renderbuffers and textures, the value of "
"GL_RENDERBUFFE_r_samples does not match the value of "
"GL_TEXTURE_SAMPLES."
);
LERROR(
"Returned if the value of GL_TEXTURE_FIXED_SAMPLE_LOCATIONS is not "
"the same for all attached textures; or , if the attached images are "
"a mix of renderbuffers and textures, the value of "
"GL_TEXTURE_FIXED_SAMPLE_LOCATIONS is not GL_TRUE for all attached "
"textures."
);
break;
case GL_FRAMEBUFFER_INCOMPLETE_LAYER_TARGETS:
LERROR(
"Returned if any framebuffer attachment is layered, and any "
"populated attachment is not layered, or if all populated color "
"attachments are not from textures of the same target."
);
break;
default:
LDEBUG("No error found checking framebuffer: " + codePosition);
break;
}
}
}
void AtmosphereDeferredcaster::renderQuadForCalc(GLuint vao, GLsizei numberOfVertices) {
glBindVertexArray(vao);
glDrawArrays(GL_TRIANGLES, 0, numberOfVertices);
glBindVertexArray(0);
}
void AtmosphereDeferredcaster::step3DTexture(
std::unique_ptr<ghoul::opengl::ProgramObject>& shaderProg,
int layer,
bool doCalculation)
{
// See OpenGL redbook 8th Edition page 556 for Layered Rendering
if (doCalculation) {
float earth2 = _atmospherePlanetRadius * _atmospherePlanetRadius;
float atm2 = _atmosphereRadius * _atmosphereRadius;
float diff = atm2 - earth2;
float ri = static_cast<float>(layer) / static_cast<float>(_r_samples - 1);
float ri_2 = ri * ri;
float epsilon =
(layer == 0) ?
0.01f :
(layer == (_r_samples - 1)) ? -0.001f : 0.0f;
float r = sqrtf(earth2 + ri_2 * diff) + epsilon;
float dminG = r - _atmospherePlanetRadius;
float dminT = _atmosphereRadius - r;
float dh = sqrtf(r * r - earth2);
float dH = dh + sqrtf(diff);
shaderProg->setUniform("r", r);
shaderProg->setUniform("dhdH", dminT, dH, dminG, dh);
}
shaderProg->setUniform("layer", static_cast<int>(layer));
}
void AtmosphereDeferredcaster::saveTextureToPPMFile(GLenum color_buffer_attachment,
const std::string& fileName,
int width, int height) const
{
std::fstream ppmFile;
ppmFile.open(fileName.c_str(), std::fstream::out);
if (ppmFile.is_open()) {
unsigned char * pixels = new unsigned char[width*height * 3];
for (int t = 0; t < width*height * 3; ++t)
pixels[t] = 255;
if (color_buffer_attachment != GL_DEPTH_ATTACHMENT) {
glReadBuffer(color_buffer_attachment);
glReadPixels(0, 0, width, height, GL_RGB, GL_UNSIGNED_BYTE, pixels);
}
else {
glReadPixels(
0,
0,
width,
height,
GL_DEPTH_COMPONENT,
GL_UNSIGNED_BYTE,
pixels
);
}
ppmFile << "P3" << std::endl;
ppmFile << width << " " << height << std::endl;
ppmFile << "255" << std::endl;
std::cout << "\n\nFILE\n\n";
int k = 0;
for (int i = 0; i < width; i++) {
for (int j = 0; j < height; j++) {
ppmFile << static_cast<unsigned int>(pixels[k]) << " "
<< static_cast<unsigned int>(pixels[k + 1]) << " "
<< static_cast<unsigned int>(pixels[k + 2]) << " ";
k += 3;
}
ppmFile << std::endl;
}
delete[] pixels;
ppmFile.close();
}
}
bool AtmosphereDeferredcaster::isAtmosphereInFrustum(const glm::dmat4& MVMatrix,
const glm::dvec3& position,
double radius) const
{
// Frustum Planes
//glm::dvec3 col1(MVMatrix[0], MVMatrix[4], MVMatrix[8]);
//glm::dvec3 col2(MVMatrix[1], MVMatrix[5], MVMatrix[9]);
//glm::dvec3 col3(MVMatrix[2], MVMatrix[6], MVMatrix[10]);
//glm::dvec3 col4(MVMatrix[3], MVMatrix[7], MVMatrix[11]);
glm::dvec3 col1(MVMatrix[0][0], MVMatrix[1][0], MVMatrix[2][0]);
glm::dvec3 col2(MVMatrix[0][1], MVMatrix[1][1], MVMatrix[2][1]);
glm::dvec3 col3(MVMatrix[0][2], MVMatrix[1][2], MVMatrix[2][2]);
glm::dvec3 col4(MVMatrix[0][3], MVMatrix[1][3], MVMatrix[2][3]);
glm::dvec3 leftNormal = col4 + col1;
glm::dvec3 rightNormal = col4 - col1;
glm::dvec3 bottomNormal = col4 + col2;
glm::dvec3 topNormal = col4 - col2;
glm::dvec3 nearNormal = col3 + col4;
glm::dvec3 farNormal = col4 - col3;
// Plane Distances
//double leftDistance = MVMatrix[15] + MVMatrix[12];
//double rightDistance = MVMatrix[15] - MVMatrix[12];
//double bottomDistance = MVMatrix[15] + MVMatrix[13];
//double topDistance = MVMatrix[15] - MVMatrix[13];
//double nearDistance = MVMatrix[15] + MVMatrix[14];
//double farDistance = MVMatrix[15] - MVMatrix[14];
double leftDistance = MVMatrix[3][3] + MVMatrix[3][0];
double rightDistance = MVMatrix[3][3] - MVMatrix[3][0];
double bottomDistance = MVMatrix[3][3] + MVMatrix[3][1];
double topDistance = MVMatrix[3][3] - MVMatrix[3][1];
double nearDistance = MVMatrix[3][3] + MVMatrix[3][2];
double farDistance = MVMatrix[3][3] - MVMatrix[3][2];
// Normalize Planes
double invMag = 1.0 / glm::length(leftNormal);
leftNormal *= invMag;
leftDistance *= invMag;
invMag = 1.0 / glm::length(rightNormal);
rightNormal *= invMag;
rightDistance *= invMag;
invMag = 1.0 / glm::length(bottomNormal);
bottomNormal *= invMag;
bottomDistance *= invMag;
invMag = 1.0 / glm::length(topNormal);
topNormal *= invMag;
topDistance *= invMag;
invMag = 1.0 / glm::length(nearNormal);
nearNormal *= invMag;
nearDistance *= invMag;
invMag = 1.0 / glm::length(farNormal);
farNormal *= invMag;
farDistance *= invMag;
if ((glm::dot(leftNormal, position) + leftDistance) < -radius) {
return false;
}
else if ((glm::dot(rightNormal, position) + rightDistance) < -radius) {
return false;
}
else if ((glm::dot(bottomNormal, position) + bottomDistance) < -radius) {
return false;
}
else if ((glm::dot(topNormal, position) + topDistance) < -radius) {
return false;
}
else if ((glm::dot(nearNormal, position) + nearDistance) < -radius) {
return false;
}
// The far plane testing is disabled because the atm has no depth.
/*else if ((glm::dot(farNormal, position) + farDistance) < -radius) {
return false;
}*/
return true;
}
} // namespace openspace