Merge branch 'reflection-uniform' into 'master'

Added a uniform to indicate whether rendering is occurring in a reflection

See merge request OpenMW/openmw!2340

apps/openmw/mwrender/renderingmanager.cpp

@@ -173,6 +173,7 @@ namespace MWRender
             stateset->addUniform(new osg::Uniform("far", 0.f));
             stateset->addUniform(new osg::Uniform("skyBlendingStart", 0.f));
             stateset->addUniform(new osg::Uniform("screenRes", osg::Vec2f{}));
+            stateset->addUniform(new osg::Uniform("isReflection", false));
             if (mUsePlayerUniforms)
             {
                 stateset->addUniform(new osg::Uniform("windSpeed", 0.0f));

apps/openmw/mwrender/water.cpp

@@ -351,6 +351,9 @@ public:
         camera->setName("ReflectionCamera");
         camera->addCullCallback(new InheritViewPointCallback);
 
+        // Inform the shader that we're in a reflection
+        camera->getOrCreateStateSet()->addUniform(new osg::Uniform("isReflection", true));
+
         // XXX: should really flip the FrontFace on each renderable instead of forcing clockwise.
         osg::ref_ptr<osg::FrontFace> frontFace(new osg::FrontFace);
         frontFace->setMode(osg::FrontFace::CLOCKWISE);