Simple drawing example.

src/visual_elements/CMakeLists.txt

@@ -1,6 +1,8 @@
 list(APPEND visual_elements_LIB_INCLUDES
     GeometryNode.cpp
-    RectangleNode.cpp
+    basic_shapes/RectangleNode.cpp
+    basic_shapes/CircleNode.cpp
+    basic_shapes/LineNode.cpp
     MaterialNode.cpp
     MeshNode.cpp
     TextNode.cpp
@@ -17,7 +19,8 @@ list(APPEND visual_elements_LIB_INCLUDES
 add_library(visual_elements SHARED ${visual_elements_LIB_INCLUDES})
 
 target_include_directories(visual_elements PUBLIC
-                          "${CMAKE_CURRENT_SOURCE_DIR}"
+                          ${CMAKE_CURRENT_SOURCE_DIR}
+                          ${CMAKE_CURRENT_SOURCE_DIR}/basic_shapes
                           )
 
 target_link_libraries(visual_elements PUBLIC core geometry fonts mesh image)

src/visual_elements/GeometryNode.h

@@ -10,7 +10,9 @@ public:
         Path,
         Rectangle,
         Circle,
-        Arc
+        Arc,
+        Line,
+        Polyline
     };
 
 public:
@@ -29,4 +31,19 @@ protected:
     bool mGeometryIsDirty{true};
 };
 
+class LineNode : public GeometryNode
+{
+public:
+    LineNode(const DiscretePoint& location)
+    :    GeometryNode(location)
+    {
+
+    }
+
+    Type getType()
+    {
+        return Type::Line;
+    }
+};
+
 using GeometryNodePtr = std::unique_ptr<GeometryNode>;

src/visual_elements/basic_shapes/CircleNode.cpp

@@ -0,0 +1,83 @@
+#include "CircleNode.h"
+
+#include "FontsManager.h"
+#include "SceneModel.h"
+#include "AbstractMesh.h"
+#include "MeshPrimitives.h"
+
+#include <iostream>
+
+CircleNode::CircleNode(const DiscretePoint& location, unsigned radius)
+:    GeometryNode(location),
+     mRadius(radius)
+{
+
+}
+
+CircleNode::Type CircleNode::getType()
+{
+    return Type::Circle;
+}
+
+unsigned CircleNode::getRadius() const
+{
+    return mRadius;
+}
+
+SceneItem* CircleNode::getSceneItem(std::size_t idx) const
+{
+    if (idx == 0)
+    {
+        return mBackgroundItem.get();
+    }
+    else
+    {
+        return nullptr;
+    }
+}
+
+unsigned CircleNode::getNumSceneItems() const
+{
+    return 1;
+}
+
+void CircleNode::setRadius(unsigned radius)
+{
+    if (mRadius != radius)
+    {
+        mRadius = radius;
+        mTransformIsDirty = true;
+    }
+
+}
+
+void CircleNode::update(FontsManager* fontsManager)
+{
+    if (!mBackgroundItem || mGeometryIsDirty)
+    {
+        auto mesh = MeshPrimitives::buildCircleAsTriMesh();
+
+        if (!mBackgroundItem)
+        {
+            mBackgroundItem = std::make_unique<SceneModel>(std::move(mesh));
+            mBackgroundItem->setName(mName + "_Model");
+        }
+        else
+        {
+            mBackgroundItem->updateMesh(std::move(mesh));
+        }
+        mGeometryIsDirty = false;
+    }
+
+    if (mTransformIsDirty)
+    {
+        mBackgroundItem->updateTransform({mLocation, static_cast<double>(2*mRadius), static_cast<double>(2*mRadius)});
+        mTransformIsDirty = false;
+    }
+
+    if (mMaterialIsDirty)
+    {
+        mBackgroundItem->updateUniformColor(mFillColor);
+        mMaterialIsDirty = false;
+    }
+}

src/visual_elements/basic_shapes/CircleNode.h

@@ -0,0 +1,25 @@
+#pragma once
+
+#include "GeometryNode.h"
+
+class CircleNode : public GeometryNode
+{
+public:
+    CircleNode(const DiscretePoint& location, unsigned radius);
+
+    Type getType();
+
+    unsigned getRadius() const;
+
+    SceneItem* getSceneItem(std::size_t idx) const override;
+    unsigned getNumSceneItems() const override;
+
+    void setRadius(unsigned radius);
+
+    void update(FontsManager* fontsManager) override;
+private:
+    unsigned mRadius{1};
+
+    std::unique_ptr<SceneModel> mBackgroundItem;
+    std::unique_ptr<SceneModel> mOutlineItem;
+};

src/visual_elements/basic_shapes/RectangleNode.h

@@ -1,9 +1,8 @@
 #pragma once
 
-#include <memory>
-
 #include "GeometryNode.h"
-#include "DiscretePoint.h"
+
+#include <memory>
 
 class RectangleNode : public GeometryNode
 {