From 886fd5efc94e92290cd1967082882fbb71e12d99 Mon Sep 17 00:00:00 2001
From: Julien Valentin <mp3butcher@hotmail.com>
Date: Thu, 16 Apr 2020 02:55:47 +0200
Subject: [PATCH] enable particle shading and force particle normal to
 (0.3,0.3,0.3) and update changelog

---
 CHANGELOG.md                    |  2 ++
 components/nifosg/nifloader.cpp |  2 ++
 components/nifosg/particle.cpp  | 27 +++++++++++++++++++++++++++
 components/nifosg/particle.hpp  |  3 +++
 4 files changed, 34 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6eff7dee0..d975eb4cb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,8 @@
 0.47.0
 ------
 
+    Bug #3676: NiParticleColorModifier isn't applied properly
+    Bug #4949: Incorrect particle lighting when force shaders = true
     Bug #5358: ForceGreeting always resets the dialogue window completely
     Bug #5363: Enchantment autocalc not always 0/1
     Bug #5364: Script fails/stops if trying to startscript an unknown script
diff --git a/components/nifosg/nifloader.cpp b/components/nifosg/nifloader.cpp
index 07cbaee37..801427b92 100644
--- a/components/nifosg/nifloader.cpp
+++ b/components/nifosg/nifloader.cpp
@@ -1078,6 +1078,8 @@ namespace NifOsg
                 trans->addChild(toAttach);
                 parentNode->addChild(trans);
             }
+            // create partsys stateset in order to pass in ShaderVisitor like all other Drawables
+            partsys->getOrCreateStateSet();
         }
 
         void triCommonToGeometry(osg::Geometry *geometry, const std::vector<osg::Vec3f>& vertices, const std::vector<osg::Vec3f>& normals, const std::vector<std::vector<osg::Vec2f>>& uvlist, const std::vector<osg::Vec4f>& colors, const std::vector<unsigned int>& boundTextures, const std::string& name)
diff --git a/components/nifosg/particle.cpp b/components/nifosg/particle.cpp
index 2a79af1c8..1b1e469bc 100644
--- a/components/nifosg/particle.cpp
+++ b/components/nifosg/particle.cpp
@@ -2,6 +2,7 @@
 
 #include <limits>
 
+#include <osg/Version>
 #include <osg/MatrixTransform>
 #include <osg/Geometry>
 
@@ -19,12 +20,19 @@ ParticleSystem::ParticleSystem()
     : osgParticle::ParticleSystem()
     , mQuota(std::numeric_limits<int>::max())
 {
+    mNormalArray = new osg::Vec3Array(1);
+    mNormalArray->setBinding(osg::Array::BIND_OVERALL);
+    (*mNormalArray.get())[0] = osg::Vec3(0.3, 0.3, 0.3);
 }
 
 ParticleSystem::ParticleSystem(const ParticleSystem &copy, const osg::CopyOp &copyop)
     : osgParticle::ParticleSystem(copy, copyop)
     , mQuota(copy.mQuota)
 {
+    mNormalArray = new osg::Vec3Array(1);
+    mNormalArray->setBinding(osg::Array::BIND_OVERALL);
+    (*mNormalArray.get())[0] = osg::Vec3(0.3, 0.3, 0.3);
+
     // For some reason the osgParticle constructor doesn't copy the particles
     for (int i=0;i<copy.numParticles()-copy.numDeadParticles();++i)
         ParticleSystem::createParticle(copy.getParticle(i));
@@ -42,6 +50,25 @@ osgParticle::Particle* ParticleSystem::createParticle(const osgParticle::Particl
     return nullptr;
 }
 
+void ParticleSystem::drawImplementation(osg::RenderInfo& renderInfo) const
+{
+    osg::State & state = *renderInfo.getState();
+#if OSG_MIN_VERSION_REQUIRED(3, 5, 6)
+    if(state.useVertexArrayObject(getUseVertexArrayObject()))
+    {
+        state.getCurrentVertexArrayState()->assignNormalArrayDispatcher();
+        state.getCurrentVertexArrayState()->setNormalArray(state, mNormalArray);
+    }
+    else
+    {
+        state.getAttributeDispatchers().activateNormalArray(mNormalArray);
+    }
+#else
+     state.Normal(0.3, 0.3, 0.3);
+#endif
+     osgParticle::ParticleSystem::drawImplementation(renderInfo);
+}
+
 void InverseWorldMatrix::operator()(osg::Node *node, osg::NodeVisitor *nv)
 {
     if (nv && nv->getVisitorType() == osg::NodeVisitor::UPDATE_VISITOR)
diff --git a/components/nifosg/particle.hpp b/components/nifosg/particle.hpp
index e159914c7..d71cbb9f5 100644
--- a/components/nifosg/particle.hpp
+++ b/components/nifosg/particle.hpp
@@ -36,8 +36,11 @@ namespace NifOsg
 
         void setQuota(int quota);
 
+        virtual void drawImplementation(osg::RenderInfo& renderInfo) const;
+
     private:
         int mQuota;
+        osg::ref_ptr<osg::Vec3Array> mNormalArray;
     };
 
     // HACK: Particle doesn't allow setting the initial age, but we need this for loading the particle system state