nodes can now be connected through the node editor

ui/nodeui.cpp

@@ -12,13 +12,15 @@
 #include <QPainter>
 
 #include "ui/effectui.h"
-#include "global/math.h"
+#include "ui/nodeedgeui.h"
 
 const int kRoundedRectRadius = 5;
 const int kNodePlugSize = 12;
 
 NodeUI::NodeUI() :
   central_widget_(nullptr),
+  proxy_(nullptr),
+  drag_destination_(nullptr),
   clicked_socket_(-1)
 {
   setFlag(QGraphicsItem::ItemIsMovable, true);
@@ -29,7 +31,6 @@ NodeUI::~NodeUI()
 {
   if (scene() != nullptr) {
     scene()->removeItem(proxy_);
-    scene()->removeItem(this);
   }
 }
 
@@ -55,8 +56,8 @@ void NodeUI::Resize(const QSize &s)
 
   rectangle.setWidth(rectangle.width() + kNodePlugSize);
 
-  path_ = QPainterPath();
-  path_.addRoundedRect(inner_rect, kRoundedRectRadius, kRoundedRectRadius);
+  drag_path_ = QPainterPath();
+  drag_path_.addRoundedRect(inner_rect, kRoundedRectRadius, kRoundedRectRadius);
 
   setRect(rectangle);
 }
@@ -66,6 +67,11 @@ void NodeUI::SetWidget(EffectUI *widget)
   central_widget_ = widget;
 }
 
+EffectUI *NodeUI::Widget()
+{
+  return central_widget_;
+}
+
 void NodeUI::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
 {
   Q_UNUSED(widget)
@@ -88,7 +94,7 @@ void NodeUI::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QW
     painter->setPen(palette.base().color());
   }
   painter->setBrush(palette.window());
-  painter->drawPath(path_);
+  painter->drawPath(drag_path_);
 }
 
 void NodeUI::mousePressEvent(QGraphicsSceneMouseEvent *event)
@@ -96,6 +102,7 @@ void NodeUI::mousePressEvent(QGraphicsSceneMouseEvent *event)
   QVector<QRectF> sockets = GetNodeSocketRects();
 
   clicked_socket_ = -1;
+  drag_destination_ = nullptr;
 
   for (int i=0;i<sockets.size();i++) {
     if (sockets.at(i).contains(event->pos())) {
@@ -106,8 +113,7 @@ void NodeUI::mousePressEvent(QGraphicsSceneMouseEvent *event)
 
   if (clicked_socket_ > -1) {
     drag_line_start_ = pos() + sockets.at(clicked_socket_).center();
-    drag_line_ = scene()->addPath(GetEdgePath(drag_line_start_, event->scenePos()),
-                                  QPen(Qt::white, 2));
+    drag_line_ = scene()->addPath(NodeEdgeUI::GetEdgePath(drag_line_start_, event->scenePos()));
 
     event->accept();
   } else {
@@ -119,7 +125,65 @@ void NodeUI::mouseMoveEvent(QGraphicsSceneMouseEvent *event)
 {
   if (clicked_socket_ > -1) {
 
-    drag_line_->setPath(GetEdgePath(drag_line_start_, event->scenePos()));
+    bool line_is_touching_node = false;
+
+    QPointF drag_line_end = event->scenePos();
+
+    // Get all the graphics items at this mouse position
+    QList<QGraphicsItem *> mouse_items = scene()->items(event->scenePos());
+    for (int j=0;j<mouse_items.size();j++) {
+
+      // See if the graphics item here is a node
+      NodeUI* mouse_node = dynamic_cast<NodeUI*>(mouse_items.at(j));
+
+      if (mouse_node != nullptr) {
+        // If so, get this node's sockets and loop through them
+        QVector<QRectF> mouse_nodes_sockets = mouse_node->GetNodeSocketRects();
+        for (int i=0;i<mouse_nodes_sockets.size();i++) {
+
+          // See if this socket contains the mouse cursor
+          if (mouse_nodes_sockets.at(i).contains(event->scenePos() - mouse_node->pos())) {
+
+            // If so, see if the two rows can be connected
+
+            EffectRow* local_row = central_widget_->GetEffect()->row(clicked_socket_);
+            EffectRow* remote_row = mouse_node->GetRowFromIndex(i);
+
+            // Ensure one is an input and one is an output and whether their data types are compatible
+            if (local_row->IsNodeInput() != remote_row->IsNodeInput()) {
+
+              // Determine which row is the input and which row is the output
+              EffectRow* input_row = (local_row->IsNodeInput()) ? local_row : remote_row;
+              EffectRow* output_row = (local_row->IsNodeInput()) ? remote_row : local_row;
+
+              if (input_row->CanAcceptDataType(output_row->OutputDataType())) {
+                // This is a valid connection
+                line_is_touching_node = true;
+
+                // Snap drag line to this socket
+                drag_line_end = mouse_node->pos() + mouse_nodes_sockets.at(i).center();
+
+                // Cancel loop since we have a connection now
+                j = mouse_items.size();
+
+                // Cache destination row
+                drag_destination_ = remote_row;
+              }
+            }
+
+            break;
+          }
+        }
+      }
+    }
+
+    if (line_is_touching_node) {
+      drag_line_->setPen(QPen(Qt::white, 2));
+    } else {
+      drag_line_->setPen(QPen(Qt::gray, 2));
+    }
+
+    drag_line_->setPath(NodeEdgeUI::GetEdgePath(drag_line_start_, drag_line_end));
 
     event->accept();
 
@@ -132,26 +196,16 @@ void NodeUI::mouseReleaseEvent(QGraphicsSceneMouseEvent *event)
 {
   if (clicked_socket_ > -1) {
     scene()->removeItem(drag_line_);
-    delete drag_line_;
     event->accept();
+
+    if (drag_destination_ != nullptr) {
+      EffectRow::ConnectEdge(central_widget_->GetEffect()->row(clicked_socket_), drag_destination_);
+    }
   } else {
     QGraphicsItem::mouseReleaseEvent(event);
   }
 }
 
-QPainterPath NodeUI::GetEdgePath(const QPointF &start_pos, const QPointF &end_pos)
-{
-  double mid_x = double_lerp(start_pos.x(), end_pos.x(), 0.5);
-
-  QPainterPath path_;
-  path_.moveTo(start_pos);
-  path_.cubicTo(QPointF(mid_x, start_pos.y()),
-                QPointF(mid_x, end_pos.y()),
-                end_pos);
-
-  return path_;
-}
-
 QVector<QRectF> NodeUI::GetNodeSocketRects()
 {
   QVector<QRectF> rects;
@@ -176,3 +230,14 @@ QVector<QRectF> NodeUI::GetNodeSocketRects()
 
   return rects;
 }
+
+EffectRow *NodeUI::GetRowFromIndex(int i)
+{
+  if (central_widget_ != nullptr) {
+    Node* e = central_widget_->GetEffect();
+    if (i < e->row_count()) {
+      return e->row(i);
+    }
+  }
+  return nullptr;
+}