From 882b63cba97913f1b3f1897d4f3da8e485c65ca3 Mon Sep 17 00:00:00 2001
From: AnyOldName3 <krizdjali+github@gmail.com>
Date: Mon, 26 Feb 2018 23:00:46 +0000
Subject: [PATCH] Make split point control parameters configurable with the new
 shadow technique.

---
 components/sceneutil/mwshadowtechnique.cpp | 16 ++++++++++++----
 components/sceneutil/mwshadowtechnique.hpp |  7 +++++++
 components/sceneutil/shadow.cpp            |  3 +++
 3 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/components/sceneutil/mwshadowtechnique.cpp b/components/sceneutil/mwshadowtechnique.cpp
index 123030b258..fbf0fc9d24 100644
--- a/components/sceneutil/mwshadowtechnique.cpp
+++ b/components/sceneutil/mwshadowtechnique.cpp
@@ -767,6 +767,16 @@ void SceneUtil::MWShadowTechnique::disableDebugHUD()
     _debugHud = nullptr;
 }
 
+void SceneUtil::MWShadowTechnique::setSplitPointUniformLogarithmicRatio(double ratio)
+{
+    _splitPointUniformLogRatio = ratio;
+}
+
+void SceneUtil::MWShadowTechnique::setSplitPointDeltaBias(double bias)
+{
+    _splitPointDeltaBias = bias;
+}
+
 MWShadowTechnique::ViewDependentData* MWShadowTechnique::createViewDependentData(osgUtil::CullVisitor* /*cv*/)
 {
     return new ViewDependentData(this);
@@ -1096,8 +1106,6 @@ void MWShadowTechnique::cull(osgUtil::CullVisitor& cv)
                 double f = reducedFar;
                 double i = double(sm_i);
                 double m = double(numShadowMapsPerLight);
-                double ratio = 0.5; // TODO: Settings::Manager::getFloat("split point uniform logarithmic ratio", "Shadows");
-                double deltaBias = 0.0; // TODO: Settings::Manager::getFloat("split point bias", "Shadows");
                 if (sm_i == 0)
                     r_start = -1.0;
                 else
@@ -1105,7 +1113,7 @@ void MWShadowTechnique::cull(osgUtil::CullVisitor& cv)
                     // compute the split point in main camera view
                     double ciLog = n * pow(f / n, i / m);
                     double ciUniform = n + (f - n) * i / m;
-                    double ci = ratio * ciLog + (1.0 - ratio) * ciUniform + deltaBias;
+                    double ci = _splitPointUniformLogRatio * ciLog + (1.0 - _splitPointUniformLogRatio) * ciUniform + _splitPointDeltaBias;
 
                     // work out where this is in light space
                     osg::Vec3d worldSpacePos = frustum.eye + frustum.frustumCenterLine * ci;
@@ -1120,7 +1128,7 @@ void MWShadowTechnique::cull(osgUtil::CullVisitor& cv)
                     // compute the split point in main camera view
                     double ciLog = n * pow(f / n, (i + 1) / m);
                     double ciUniform = n + (f - n) * (i + 1) / m;
-                    double ci = ratio * ciLog + (1.0 - ratio) * ciUniform + deltaBias;
+                    double ci = _splitPointUniformLogRatio * ciLog + (1.0 - _splitPointUniformLogRatio) * ciUniform + _splitPointDeltaBias;
 
                     // work out where this is in light space
                     osg::Vec3d worldSpacePos = frustum.eye + frustum.frustumCenterLine * ci;
diff --git a/components/sceneutil/mwshadowtechnique.hpp b/components/sceneutil/mwshadowtechnique.hpp
index 41f1d7c32d..1fad0eee52 100644
--- a/components/sceneutil/mwshadowtechnique.hpp
+++ b/components/sceneutil/mwshadowtechnique.hpp
@@ -69,6 +69,10 @@ namespace SceneUtil {
 
         virtual void disableDebugHUD();
 
+        virtual void setSplitPointUniformLogarithmicRatio(double ratio);
+
+        virtual void setSplitPointDeltaBias(double bias);
+
         class ComputeLightSpaceBounds : public osg::NodeVisitor, public osg::CullStack
         {
         public:
@@ -232,6 +236,9 @@ namespace SceneUtil {
 
         bool                                    _enableShadows;
 
+        double                                  _splitPointUniformLogRatio = 0.5;
+        double                                  _splitPointDeltaBias = 0.0;
+
         class DebugHUD : public osg::Referenced
         {
         public:
diff --git a/components/sceneutil/shadow.cpp b/components/sceneutil/shadow.cpp
index 8c58cb6033..99cb71beb1 100644
--- a/components/sceneutil/shadow.cpp
+++ b/components/sceneutil/shadow.cpp
@@ -40,6 +40,9 @@ namespace SceneUtil
         int mapres = Settings::Manager::getInt("shadow map resolution", "Shadows");
         settings->setTextureSize(osg::Vec2s(mapres, mapres));
 
+        mShadowTechnique->setSplitPointUniformLogarithmicRatio(Settings::Manager::getFloat("split point uniform logarithmic ratio", "Shadows"));
+        mShadowTechnique->setSplitPointDeltaBias(Settings::Manager::getFloat("split point bias", "Shadows"));
+
         if (Settings::Manager::getBool("enable debug hud", "Shadows"))
             mShadowTechnique->enableDebugHUD();
         else