diff --git a/CMakeLists.txt b/CMakeLists.txt
index ba25f38..5b43982 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -54,6 +54,7 @@ set(GUI_SOURCES
 # qt
 find_package(Qt6 REQUIRED COMPONENTS Core Widgets SvgWidgets OpenGLWidgets)
 qt_standard_project_setup()
+ADD_DEFINITIONS(-DQT_NO_KEYWORDS)
 
 # glm
 find_package(glm REQUIRED)
diff --git a/src/Engine/Network/NetworkManager.cpp b/src/Engine/Network/NetworkManager.cpp
index 1768f22..738cb98 100644
--- a/src/Engine/Network/NetworkManager.cpp
+++ b/src/Engine/Network/NetworkManager.cpp
@@ -15,7 +15,19 @@ enzo::nt::OpId enzo::nt::NetworkManager::addOperator(op::OpInfo opInfo)
 {
 
     maxOpId_++;
-    gopStore_.emplace(maxOpId_, std::make_unique<GeometryOperator>(maxOpId_, opInfo));
+    std::unique_ptr<GeometryOperator> newOp = std::make_unique<GeometryOperator>(maxOpId_, opInfo);
+    newOp->nodeDirtied.connect(
+        [this](nt::OpId opId)
+        {
+            cookOp(opId);
+
+            if(getDisplayOp()==opId)
+            {
+                enzo::nt::GeometryOperator& displayOp = getGeoOperator(opId);
+                updateDisplay(displayOp.getOutputGeo(0));
+            }
+        });
+    gopStore_.emplace(maxOpId_, std::move(newOp));
     std::cout << "adding operator " << maxOpId_ << "\n";
 
     return maxOpId_;
@@ -51,27 +63,25 @@ bool enzo::nt::NetworkManager::isValidOp(nt::OpId opId)
 
 void enzo::nt::NetworkManager::setDisplayOp(OpId opId)
 {
-    std::cout << "gop size before: " << gopStore_.size() <<"\n";
     displayOp_=opId;
-    std::vector<enzo::nt::OpId> dependencyGraph = getDependencyGraph(opId);
-    enzo::geo::Geometry prevGeometry;
-    std::cout << "size: " << dependencyGraph.size() << "\n";
+    
+    cookOp(opId);
 
-    for(enzo::nt::OpId dependencyOpId : dependencyGraph)
-    {
-        cookOp(dependencyOpId);
-    }
-    std::cout << "gop size middle: " << gopStore_.size() <<"\n"; // <- size: 1
     enzo::nt::GeometryOperator& displayOp = getGeoOperator(opId);
     updateDisplay(displayOp.getOutputGeo(0));
-    std::cout << "gop size after: " << gopStore_.size() <<"\n";
+    displayNodeChanged();
 }
 
 void enzo::nt::NetworkManager::cookOp(enzo::nt::OpId opId)
 {
-    enzo::nt::GeometryOperator& op = getGeoOperator(opId);
-    enzo::op::Context context(opId, enzo::nt::nm());
-    op.cookOp(context);
+    std::vector<enzo::nt::OpId> dependencyGraph = getDependencyGraph(opId);
+
+    for(enzo::nt::OpId dependencyOpId : dependencyGraph)
+    {
+        enzo::nt::GeometryOperator& op = getGeoOperator(dependencyOpId);
+        enzo::op::Context context(dependencyOpId, enzo::nt::nm());
+        op.cookOp(context);
+    }
 }
 
 std::vector<enzo::nt::OpId> enzo::nt::NetworkManager::getDependencyGraph(enzo::nt::OpId opId)
diff --git a/src/Engine/Network/NetworkManager.h b/src/Engine/Network/NetworkManager.h
index 5ea01b1..87a6043 100644
--- a/src/Engine/Network/NetworkManager.h
+++ b/src/Engine/Network/NetworkManager.h
@@ -24,6 +24,8 @@ public:
     GeometryOperator& getGeoOperator(nt::OpId opId);
     void setDisplayOp(OpId opId);
 
+    boost::signals2::signal<void ()> displayNodeChanged;
+
     #ifdef UNIT_TEST
         void _reset();
     #endif
@@ -42,7 +44,9 @@ private:
     enzo::nt::OpId maxOpId_=0;
     // operator selected for displaying in the viewport
     std::optional<OpId> displayOp_=std::nullopt;
-signals:
+
+
+Q_SIGNALS:
     void updateDisplay(enzo::geo::Geometry& geometry);
 
 };
diff --git a/src/Engine/Operator/Context.cpp b/src/Engine/Operator/Context.cpp
index 34eecaa..27d47bd 100644
--- a/src/Engine/Operator/Context.cpp
+++ b/src/Engine/Operator/Context.cpp
@@ -1,6 +1,8 @@
 #include "Engine/Operator/Context.h"
 #include "Engine/Network/NetworkManager.h"
+#include "Engine/Parameter/Parameter.h"
 #include <iostream>
+#include <memory>
 
 
 enzo::op::Context::Context(enzo::nt::OpId opId, enzo::nt::NetworkManager& networkManager)
@@ -23,3 +25,13 @@ enzo::geo::Geometry enzo::op::Context::cloneInputGeo(unsigned int inputIndex)
     return networkManager_.getGeoOperator(inputConnection->getInputOpId()).getOutputGeo(inputConnection->getInputIndex());
 }
 
+enzo::bt::floatT enzo::op::Context::evalFloatParm(const char* parmName) const
+{
+    enzo::nt::GeometryOperator& selfOp = networkManager_.getGeoOperator(opId_);
+    std::weak_ptr<prm::Parameter> parameter = selfOp.getParameter(parmName);
+
+    if(auto sharedParm = parameter.lock())
+    {
+        return sharedParm->evalFloat();
+    }
+}
diff --git a/src/Engine/Operator/Context.h b/src/Engine/Operator/Context.h
index c89c37f..96dd46c 100644
--- a/src/Engine/Operator/Context.h
+++ b/src/Engine/Operator/Context.h
@@ -15,6 +15,7 @@ class Context
 public:
     Context(enzo::nt::OpId opId, enzo::nt::NetworkManager& networkManager);
     enzo::geo::Geometry cloneInputGeo(unsigned int inputIndex);
+    bt::floatT evalFloatParm(const char* parmName) const;
 private:
     enzo::nt::OpId opId_;
     enzo::nt::NetworkManager& networkManager_;
diff --git a/src/Engine/Operator/GeometryOpDef.h b/src/Engine/Operator/GeometryOpDef.h
index 2a671df..9ffaee9 100644
--- a/src/Engine/Operator/GeometryOpDef.h
+++ b/src/Engine/Operator/GeometryOpDef.h
@@ -20,6 +20,7 @@ private:
     unsigned int minInputs_;
     unsigned int maxInputs_;
     unsigned int maxOutputs_;
+
 protected:
     enzo::nt::OpId opId_;
     const enzo::geo::Geometry& getInputGeoView(unsigned int inputIndex);
diff --git a/src/Engine/Operator/GeometryOperator.cpp b/src/Engine/Operator/GeometryOperator.cpp
index bbc6234..f66ee81 100644
--- a/src/Engine/Operator/GeometryOperator.cpp
+++ b/src/Engine/Operator/GeometryOperator.cpp
@@ -41,16 +41,24 @@ void nt::GeometryOperator::initParameters()
     {
         std::cout << "name: " << t->getName() << "\n";
         // create parameter
-        parameters_.push_back(
-            std::make_shared<prm::Parameter>(*t)
-        );
+        auto parameter = std::make_shared<prm::Parameter>(*t);
+        parameter->valueChanged.connect(boost::bind(&GeometryOperator::dirtyNode, this));
+
+        parameters_.push_back(parameter);
     }
 
 }
 
+void enzo::nt::GeometryOperator::dirtyNode()
+{
+    dirty_=true;
+    nodeDirtied(opId_);
+}
+
 void enzo::nt::GeometryOperator::cookOp(op::Context context)
 {
     opDef_->cookOp(context);
+    dirty_=false;
 }
 
 geo::Geometry& enzo::nt::GeometryOperator::getOutputGeo(unsigned outputIndex)
@@ -74,6 +82,19 @@ void nt::GeometryOperator::addOutputConnection(std::shared_ptr<nt::GeometryConne
     std::cout << "size: " << outputConnections_.size() << "\n";
 }
 
+std::weak_ptr<prm::Parameter> nt::GeometryOperator::getParameter(std::string parameterName)
+{
+    for(auto parm : parameters_)
+    {
+        if(parm->getName()==parameterName)
+        {
+            return parm;
+        }
+    }
+    return std::weak_ptr<prm::Parameter>();
+
+}
+
 std::vector<std::shared_ptr<const nt::GeometryConnection>> nt::GeometryOperator::getInputConnections() const
 {
     std::vector<std::shared_ptr<const nt::GeometryConnection>> inputConnections;
diff --git a/src/Engine/Operator/GeometryOperator.h b/src/Engine/Operator/GeometryOperator.h
index 43b4d83..827114f 100644
--- a/src/Engine/Operator/GeometryOperator.h
+++ b/src/Engine/Operator/GeometryOperator.h
@@ -27,11 +27,18 @@ public:
     std::vector<std::shared_ptr<const GeometryConnection>> getInputConnections() const;
     std::vector<std::shared_ptr<const GeometryConnection>> getOutputConnections() const;
     std::vector<std::weak_ptr<prm::Parameter>> getParameters();
+    std::weak_ptr<prm::Parameter> getParameter(std::string parameterName);
+
+    void dirtyNode();
 
 
     unsigned int getMaxInputs() const;
     unsigned int getMaxOutputs() const;
 
+    // signals
+    boost::signals2::signal<void (nt::OpId)> nodeDirtied;
+
+
 
 private:
     void initParameters();
@@ -45,5 +52,6 @@ private:
     std::unique_ptr<enzo::nt::GeometryOpDef> opDef_;
     enzo::nt::OpId opId_;
     enzo::op::OpInfo opInfo_;
+    bool dirty_ = true;
 };
 }
diff --git a/src/Engine/Parameter/Parameter.cpp b/src/Engine/Parameter/Parameter.cpp
index 6399446..bbe193e 100644
--- a/src/Engine/Parameter/Parameter.cpp
+++ b/src/Engine/Parameter/Parameter.cpp
@@ -1,10 +1,10 @@
 #include "Engine/Parameter/Parameter.h"
 #include <iostream>
 
-
 enzo::prm::Parameter::Parameter(Template prmTemplate)
 : template_{prmTemplate}
 {
+    floatValue_ = prmTemplate.getDefault();
     std::cout << "created new parameter: " << prmTemplate.getName() << "\n";
 }
 
@@ -20,5 +20,6 @@ enzo::bt::floatT enzo::prm::Parameter::evalFloat() const
 void enzo::prm::Parameter::setFloat(bt::floatT value)
 {
     floatValue_ = value;
+    valueChanged();
 }
 
diff --git a/src/Engine/Parameter/Parameter.h b/src/Engine/Parameter/Parameter.h
index e2ce818..dbf9cba 100644
--- a/src/Engine/Parameter/Parameter.h
+++ b/src/Engine/Parameter/Parameter.h
@@ -1,6 +1,7 @@
 #pragma once
 #include "Engine/Parameter/Template.h"
 #include "Engine/Types.h"
+#include <boost/signals2.hpp>
 
 namespace enzo::prm
 {
@@ -11,6 +12,7 @@ public:
     std::string getName() const;
     bt::floatT evalFloat() const;
     void setFloat(bt::floatT value);
+    boost::signals2::signal<void ()> valueChanged;
 private:
     Template template_;
     bt::floatT floatValue_ = 0;
diff --git a/src/Engine/Parameter/Template.cpp b/src/Engine/Parameter/Template.cpp
index 2768e1e..ff699ef 100644
--- a/src/Engine/Parameter/Template.cpp
+++ b/src/Engine/Parameter/Template.cpp
@@ -1,8 +1,8 @@
 #include "Engine/Parameter/Template.h"
 #include "Engine/Parameter/Type.h"
 
-enzo::prm::Template::Template(enzo::prm::Type type, const char* name)
-: type_{type}, name_{name}
+enzo::prm::Template::Template(enzo::prm::Type type, const char* name, bt::floatT theDefault)
+: type_{type}, name_{name}, default_{theDefault}
 {
     
 }
@@ -18,6 +18,11 @@ bool enzo::prm::Template::isValid() const
 
 }
 
+const enzo::bt::floatT enzo::prm::Template::getDefault() const
+{
+    return default_;
+}
+
 const char* enzo::prm::Template::getName() const
 {
     return name_;
diff --git a/src/Engine/Parameter/Template.h b/src/Engine/Parameter/Template.h
index 6e69d38..b34cde2 100644
--- a/src/Engine/Parameter/Template.h
+++ b/src/Engine/Parameter/Template.h
@@ -1,5 +1,6 @@
 #pragma once
 #include "Engine/Parameter/Type.h"
+#include "Engine/Types.h"
 
 namespace enzo::prm
 {
@@ -7,12 +8,19 @@ namespace enzo::prm
 class Template
 {
 public:
-    Template(enzo::prm::Type type, const char* name);
+    Template(
+        enzo::prm::Type type,
+        const char* name,
+        // TODO: change default to class that can store multiple types
+        bt::floatT theDefault
+    );
     Template();
     const char* getName() const;
+    const bt::floatT getDefault() const;
     bool isValid() const;
 private:
     enzo::prm::Type type_;
+    bt::floatT default_;
     // TODO: make a class that holds token and name
     const char* name_;
 
diff --git a/src/Gui/Interface.cpp b/src/Gui/Interface.cpp
index ffd80cf..9a6a1bf 100644
--- a/src/Gui/Interface.cpp
+++ b/src/Gui/Interface.cpp
@@ -55,7 +55,8 @@ EnzoUI::EnzoUI()
 
     // connect signals
     connect(&enzo::nt::nm(), &enzo::nt::NetworkManager::updateDisplay, viewport, &Viewport::geometryChanged);
-    connect(&enzo::nt::nm(), &enzo::nt::NetworkManager::updateDisplay, parametersPanel, &ParametersPanel::selectionChanged);
+    enzo::nt::nm().displayNodeChanged.connect([parametersPanel](){parametersPanel->selectionChanged();});
+    // connect(&enzo::nt::nm(), &enzo::nt::NetworkManager::updateDisplay, parametersPanel, &ParametersPanel::selectionChanged);
 
 //  ─── end of EnzoUI ctor ───
 QTimer::singleShot(0, this, [=] {
diff --git a/src/Gui/Network/TabMenu.h b/src/Gui/Network/TabMenu.h
index 12f6f65..fa158bc 100644
--- a/src/Gui/Network/TabMenu.h
+++ b/src/Gui/Network/TabMenu.h
@@ -59,7 +59,7 @@ protected:
     void focusOutEvent(QFocusEvent *event) override;
     bool event(QEvent *event) override;
     // void resizeEvent(QResizeEvent *event) override;
-protected slots:
+protected Q_SLOTS:
     void nodeClicked();
 };
 
diff --git a/src/Gui/Parameters/AbstractFormParm.cpp b/src/Gui/Parameters/AbstractFormParm.cpp
index 64f605a..629c413 100644
--- a/src/Gui/Parameters/AbstractFormParm.cpp
+++ b/src/Gui/Parameters/AbstractFormParm.cpp
@@ -16,7 +16,6 @@ enzo::ui::AbstractFormParm::AbstractFormParm(std::weak_ptr<prm::Parameter> param
         label->setSizePolicy(QSizePolicy::Maximum, QSizePolicy::Preferred);
 
         auto slider = new AbstractSliderParm();
-        connect(slider, &AbstractSliderParm::valueChanged, this, &AbstractFormParm::changeValue); 
         slider->setValue(sharedParameter->evalFloat());
 
         mainLayout_ = new QHBoxLayout();
@@ -28,6 +27,8 @@ enzo::ui::AbstractFormParm::AbstractFormParm(std::weak_ptr<prm::Parameter> param
         setProperty("class", "Parameter");
         setStyleSheet(".Parameter { background-color: none;}");
         setLayout(mainLayout_);
+
+        connect(slider, &AbstractSliderParm::valueChanged, this, &AbstractFormParm::changeValue); 
     }
 
 }
diff --git a/src/Gui/Parameters/AbstractFormParm.h b/src/Gui/Parameters/AbstractFormParm.h
index d2279bb..3b58e89 100644
--- a/src/Gui/Parameters/AbstractFormParm.h
+++ b/src/Gui/Parameters/AbstractFormParm.h
@@ -2,6 +2,7 @@
 #include <QWidget>
 #include <QHBoxLayout>
 #include <memory>
+#include <qtmetamacros.h>
 
 namespace enzo::ui
 {
@@ -9,13 +10,13 @@ namespace enzo::ui
 class AbstractFormParm
 : public QWidget
 {
+    Q_OBJECT
 public:
     AbstractFormParm(std::weak_ptr<prm::Parameter> parameter);
 
-protected slots:
+protected Q_SLOTS:
     void changeValue(bt::floatT value);
 
-
 private:
     QHBoxLayout* mainLayout_;
     std::weak_ptr<prm::Parameter> parameter_;
diff --git a/src/Gui/Parameters/AbstractSliderParm.h b/src/Gui/Parameters/AbstractSliderParm.h
index 640321c..1e28496 100644
--- a/src/Gui/Parameters/AbstractSliderParm.h
+++ b/src/Gui/Parameters/AbstractSliderParm.h
@@ -15,7 +15,7 @@ public:
     AbstractSliderParm(QWidget *parent = nullptr, Qt::WindowFlags f = Qt::WindowFlags());
     void setValue(bt::floatT value);
 
-signals:
+Q_SIGNALS:
     void valueChanged(bt::floatT value); 
 
 private:
diff --git a/src/Gui/ParametersPanel/ParametersPanel.h b/src/Gui/ParametersPanel/ParametersPanel.h
index 8749474..5a99de1 100644
--- a/src/Gui/ParametersPanel/ParametersPanel.h
+++ b/src/Gui/ParametersPanel/ParametersPanel.h
@@ -8,7 +8,7 @@ class ParametersPanel
 {
 public:
     ParametersPanel(QWidget *parent = nullptr, Qt::WindowFlags f = Qt::WindowFlags());
-public slots:
+public Q_SLOTS:
     void selectionChanged();
 private:
     QVBoxLayout* mainLayout_;
diff --git a/src/Gui/Viewport/Viewport.h b/src/Gui/Viewport/Viewport.h
index bf63d68..fe86376 100644
--- a/src/Gui/Viewport/Viewport.h
+++ b/src/Gui/Viewport/Viewport.h
@@ -23,6 +23,6 @@ private:
     QPointF leftStartPos_;
     bool rightMouseDown_=false;
     QPointF rightStartPos_;
-public slots:
+public Q_SLOTS:
     void geometryChanged(enzo::geo::Geometry& geometry);
 };
diff --git a/src/Gui/Viewport/ViewportGLWidget.h b/src/Gui/Viewport/ViewportGLWidget.h
index 0c02d31..2917873 100644
--- a/src/Gui/Viewport/ViewportGLWidget.h
+++ b/src/Gui/Viewport/ViewportGLWidget.h
@@ -25,6 +25,6 @@ protected:
     void resizeGL(int w, int h) override;
     void paintGL() override;
 
-public slots:
+public Q_SLOTS:
     void geometryChanged(enzo::geo::Geometry& geometry);
 };
diff --git a/src/OpDefs/CMakeLists.txt b/src/OpDefs/CMakeLists.txt
index f58e6db..0ed25a4 100644
--- a/src/OpDefs/CMakeLists.txt
+++ b/src/OpDefs/CMakeLists.txt
@@ -18,6 +18,7 @@ add_library(${libName} SHARED
     ../Engine/Operator/Attribute.cpp
     ../Engine/Network/NetworkManager.cpp
     ../Engine/Parameter/Template.cpp
+    ../Engine/Parameter/Parameter.cpp
     GopTransform.cpp
     GopHouse.cpp
 )
diff --git a/src/OpDefs/GopHouse.cpp b/src/OpDefs/GopHouse.cpp
index 4610be1..beacaf5 100644
--- a/src/OpDefs/GopHouse.cpp
+++ b/src/OpDefs/GopHouse.cpp
@@ -48,7 +48,7 @@ void GOP_house::cookOp(enzo::op::Context context)
         for(int i=0; i<PAttrHandle.getAllValues().size(); ++i)
         {
             enzo::bt::Vector3 vector = PAttrHandle.getValue(i);
-            vector.x()+=2.5;
+            vector*=context.evalFloatParm("size");
             PAttrHandle.setValue(i, vector);
         }
         // ----
@@ -69,18 +69,10 @@ void GOP_house::cookOp(enzo::op::Context context)
         setOutputGeometry(0, geo);
     }
 
-    // if(outputRequested(1))
-    // {
-    //     // create new geometry
-    //     const geo::Geometry& geo1 = getInputGeoView(0);
-    //     geo::Geometry geo2;
-
-    //     setOutputGeometry(1, geo2);
-    // }
 }
 
 enzo::prm::Template GOP_house::parameterList[] =
 {
-    enzo::prm::Template(enzo::prm::Type::FLOAT, "Size"),
+    enzo::prm::Template(enzo::prm::Type::FLOAT, "size", 1),
     enzo::prm::Terminator
 };
diff --git a/src/OpDefs/GopTransform.cpp b/src/OpDefs/GopTransform.cpp
index c146855..1113a48 100644
--- a/src/OpDefs/GopTransform.cpp
+++ b/src/OpDefs/GopTransform.cpp
@@ -26,7 +26,9 @@ void GopTransform::cookOp(enzo::op::Context context)
         for(int i=0; i<PAttrHandle.getAllValues().size(); ++i)
         {
             enzo::bt::Vector3 vector = PAttrHandle.getValue(i);
-            vector.y()+=2.5;
+            vector.x()+=context.evalFloatParm("translateX");
+            vector.y()+=context.evalFloatParm("translateY");
+            vector.z()+=context.evalFloatParm("translateZ");
             PAttrHandle.setValue(i, vector);
         }
         // ----
@@ -41,9 +43,9 @@ void GopTransform::cookOp(enzo::op::Context context)
 
 enzo::prm::Template GopTransform::parameterList[] = 
 {
-    enzo::prm::Template(enzo::prm::Type::FLOAT, "translateX"),
-    enzo::prm::Template(enzo::prm::Type::FLOAT, "translateY"),
-    enzo::prm::Template(enzo::prm::Type::FLOAT, "translateZ"),
+    enzo::prm::Template(enzo::prm::Type::FLOAT, "translateX", 0),
+    enzo::prm::Template(enzo::prm::Type::FLOAT, "translateY", 0),
+    enzo::prm::Template(enzo::prm::Type::FLOAT, "translateZ", 0),
     enzo::prm::Terminator
 };