Initial selection implementation.

1 files changed, 125 insertions, 25 deletions

diff --git a/scatterplot.cpp b/scatterplot.cpp
index a3a0dfc..414f46a 100644
--- a/scatterplot.cpp
+++ b/scatterplot.cpp
@@ -16,9 +16,22 @@ const float PI = 3.1415f;
 
 Scatterplot::Scatterplot(QQuickItem *parent)
     : QQuickItem(parent)
-    , m_colorScale{QColor("red"), QColor("green"), QColor("blue")}
+    , m_dragOriginPos(-1.0, -1.0)
+    , m_colorScale{
+        QColor("#1f77b4"),
+        QColor("#ff7f0e"),
+        QColor("#2ca02c"),
+        QColor("#d62728"),
+        QColor("#9467bd"),
+        QColor("#8c564b"),
+        QColor("#e377c2"),
+        QColor("#7f7f7f"),
+        QColor("#bcbd22"),
+    }
 {
+    setClip(true);
     setFlag(QQuickItem::ItemHasContents);
+    setAcceptedMouseButtons(Qt::LeftButton | Qt::RightButton);
 }
 
 Scatterplot::~Scatterplot()
@@ -71,51 +84,138 @@ void updateSquareGeometry(QSGGeometry *geometry, float size, float cx, float cy)
     vertexData[3].set(cx - r, cy + r);
 }
 
+void updateSelectionGeometry(QSGGeometry *geometry, const QPointF &p1, const QPointF &p2)
+{
+    QSGGeometry::Point2D *vertexData = geometry->vertexDataAsPoint2D();
+    vertexData[0].set(p1.x(), p1.y());
+    vertexData[1].set(p2.x(), p1.y());
+    vertexData[2].set(p2.x(), p2.y());
+    vertexData[3].set(p1.x(), p2.y());
+}
+
+QSGNode *Scatterplot::newGlyphNodeTree() {
+    QSGNode *node = new QSGNode;
+    int vertexCount = calculateCircleVertexCount(GLYPH_SIZE / 2);
+
+    for (arma::uword i = 0; i < m_data.n_rows; i++) {
+        QSGGeometryNode *glyphNode = new QSGGeometryNode;
+
+        QSGGeometry *geometry = new QSGGeometry(QSGGeometry::defaultAttributes_Point2D(), vertexCount);
+        geometry->setDrawingMode(GL_POLYGON);
+        glyphNode->setGeometry(geometry);
+        glyphNode->setFlag(QSGNode::OwnsGeometry);
+
+        QSGFlatColorMaterial *material = new QSGFlatColorMaterial;
+        material->setColor(m_colorScale.color(m_data(i, 2)));
+        glyphNode->setMaterial(material);
+        glyphNode->setFlag(QSGNode::OwnsMaterial);
+
+        node->appendChildNode(glyphNode);
+    }
+
+    return node;
+}
+
 QSGNode *Scatterplot::updatePaintNode(QSGNode *oldNode, UpdatePaintNodeData *)
 {
     if (m_data.n_rows < 1)
         return 0;
 
-    QSGNode *node = 0;
-    int vertexCount = calculateCircleVertexCount(GLYPH_SIZE / 2);
     qreal xmin = m_data.col(0).min(),
           xmax = m_data.col(0).max(),
           ymin = m_data.col(1).min(),
           ymax = m_data.col(1).max(),
           x, y;
 
+    QSGNode *root = 0;
     if (!oldNode) {
-        node = new QSGNode;
-        for (arma::uword i = 0; i < m_data.n_rows; i++) {
-            QSGGeometryNode *childNode = new QSGGeometryNode;
-
-            QSGGeometry *geometry = new QSGGeometry(QSGGeometry::defaultAttributes_Point2D(), vertexCount);
-            geometry->setDrawingMode(GL_POLYGON);
-            childNode->setGeometry(geometry);
-            childNode->setFlag(QSGNode::OwnsGeometry);
-
-            QSGFlatColorMaterial *material = new QSGFlatColorMaterial;
-            material->setColor(m_colorScale.color(m_data(i, 2)));
-            childNode->setMaterial(material);
-            childNode->setFlag(QSGNode::OwnsMaterial);
-
-            node->appendChildNode(childNode);
-        }
+        root = new QSGNode;
+        root->appendChildNode(newGlyphNodeTree());
     } else {
-        node = oldNode;
+        root = oldNode;
     }
 
-    QSGNode *childNode = node->firstChild();
+    QSGNode *glyphNode = root->firstChild()->firstChild();
     for (arma::uword i = 0; i < m_data.n_rows; i++) {
         arma::rowvec row = m_data.row(i);
         x = PADDING + (row[0] - xmin) / (xmax - xmin) * (width() - 2*PADDING);
         y = PADDING + (row[1] - ymin) / (ymax - ymin) * (height() - 2*PADDING);
 
-        QSGGeometry *geometry = static_cast<QSGGeometryNode *>(childNode)->geometry();
+        QSGGeometry *geometry = static_cast<QSGGeometryNode *>(glyphNode)->geometry();
         updateCircleGeometry(geometry, GLYPH_SIZE, x, y);
-        childNode->markDirty(QSGNode::DirtyGeometry);
-        childNode = childNode->nextSibling();
+        glyphNode->markDirty(QSGNode::DirtyGeometry);
+        glyphNode = glyphNode->nextSibling();
     }
 
-    return node;
+    // Draw selection
+    if (m_currentState == INTERACTION_SELECTING) {
+        QSGGeometryNode *selectionNode = 0;
+        if (!root->firstChild()->nextSibling()) {
+            selectionNode = new QSGGeometryNode;
+            QSGGeometry *geometry = new QSGGeometry(QSGGeometry::defaultAttributes_Point2D(), 4);
+            geometry->setDrawingMode(GL_POLYGON);
+            selectionNode->setGeometry(geometry);
+            selectionNode->setFlag(QSGNode::OwnsGeometry);
+
+            QSGFlatColorMaterial *material = new QSGFlatColorMaterial;
+            material->setColor(QColor(128, 128, 128, 128));
+            selectionNode->setMaterial(material);
+            selectionNode->setFlag(QSGNode::OwnsMaterial);
+
+            root->appendChildNode(selectionNode);
+        } else {
+            selectionNode = static_cast<QSGGeometryNode *>(root->firstChild()->nextSibling());
+        }
+
+        updateSelectionGeometry(selectionNode->geometry(), m_dragOriginPos, m_dragCurrentPos);
+        selectionNode->markDirty(QSGNode::DirtyGeometry);
+    } else if (m_currentState == INTERACTION_NONE) {
+        if (root->firstChild()->nextSibling()) {
+            root->firstChild()->nextSibling()->markDirty(QSGNode::DirtyGeometry);
+            root->removeChildNode(root->firstChild()->nextSibling());
+        }
+    }
+
+    return root;
+}
+
+void Scatterplot::mousePressEvent(QMouseEvent *event)
+{
+    switch (m_currentState) {
+    case INTERACTION_NONE:
+        m_currentState = INTERACTION_SELECTING;
+        m_dragOriginPos = event->localPos();
+        break;
+    case INTERACTION_SELECTED:
+        m_currentState = INTERACTION_MOVING;
+        break; // TODO
+    case INTERACTION_SELECTING:
+    case INTERACTION_MOVING:
+        return; // should not be reached
+    }
+}
+
+void Scatterplot::mouseMoveEvent(QMouseEvent *event)
+{
+    if (m_currentState != INTERACTION_SELECTING)
+        return;
+
+    m_dragCurrentPos = event->localPos();
+    update();
+}
+
+void Scatterplot::mouseReleaseEvent(QMouseEvent *event)
+{
+    switch (m_currentState) {
+    case INTERACTION_SELECTING:
+        m_currentState = INTERACTION_NONE;
+        update();
+        break;
+
+    case INTERACTION_MOVING:
+        break;
+    case INTERACTION_NONE:
+    case INTERACTION_SELECTED:
+        return; // should not be reached
+    }
 }