[ui] GraphEditor: improved ToolBar

* replace text buttons with MaterialToolButtons
* hide advanced min/max depth settings to a Settings menu

meshroom/ui/qml/GraphEditor/GraphEditor.qml

@@ -1,6 +1,8 @@
 import QtQuick 2.7
 import QtQuick.Controls 2.3
 import QtQuick.Layouts 1.3
+import Controls 1.0
+import MaterialIcons 2.2
 
 /**
   A component displaying a Graph (nodes, attributes and edges).
@@ -345,25 +347,58 @@ Item {
         }
     }
 
-    Row {
+    // Toolbar
+    FloatingPane {
+        padding: 2
         anchors.bottom: parent.bottom
+        RowLayout {
+            spacing: 4
+            // Fit
+            MaterialToolButton {
+                text: MaterialIcons.fullscreen
+                ToolTip.text: "Fit"
+                onClicked: root.fit()
+            }
+            // Auto-Layout
+            MaterialToolButton {
+                text: MaterialIcons.linear_scale
+                ToolTip.text: "Auto-Layout"
+                onClicked: uigraph.layout.reset()
+            }
 
-        Button {
+            // Separator
-            text: "Fit"
+            Rectangle {
-            onClicked: root.fit()
+                Layout.fillHeight: true
-            z: 10
+                Layout.margins: 2
-        }
+                implicitWidth: 1
-
+                color: activePalette.window
-        Button {
+            }
-            text: "Layout"
+            // Settings
-            onClicked: uigraph.layout.reset()
+            MaterialToolButton {
-            z: 10
+                text: MaterialIcons.settings
-        }
+                font.pointSize: 11
-        ComboBox {
+                onClicked: menu.open()
-            model: ['Min Depth', 'Max Depth']
+                Menu {
-            currentIndex: uigraph.layout.depthMode
+                    id: menu
-            onActivated: {
+                    y: -height
-                uigraph.layout.depthMode = currentIndex
+                    padding: 4
+                    RowLayout {
+                        spacing: 2
+                        Label {
+                            padding: 2
+                            text: "Auto-Layout Depth:"
+                        }
+                        ComboBox {
+                            flat: true
+                            model: ['Minimum', 'Maximum']
+                            implicitWidth: 80
+                            currentIndex: uigraph.layout.depthMode
+                            onActivated: {
+                                uigraph.layout.depthMode = currentIndex
+                            }
+                        }
+                    }
+                }
             }
         }
     }

meshroom/ui/qml/main.qml

@@ -440,13 +440,16 @@ ApplicationWindow {
                 Item {
                     Layout.fillHeight: true
                     Layout.fillWidth: true
-                    Layout.margins: 10
+                    Layout.margins: 2
+
                     GraphEditor {
                         id: graphEditor
+
                         anchors.fill: parent
                         uigraph: _reconstruction
                         nodeTypesModel: _nodeTypes
                         readOnly: _reconstruction.computing
+
                         onNodeDoubleClicked: {
                             if(node.nodeType == "StructureFromMotion")
                             {