feat: Implement floating feature browser in viewport with transparent background

Co-authored-by: aider (gemini/gemini-2.5-pro) <aider@aider.chat>

src/ViewportWidget.cpp

@@ -1,6 +1,9 @@
 #include "ViewportWidget.h"
 #include "ViewCube.h"
 #include "SketchGrid.h"
+#include "Document.h"
+#include "Feature.h"
+#include <algorithm>
 #include <QMouseEvent>
 #include <QWheelEvent>
 #include <QApplication>
@@ -21,6 +24,11 @@ ViewportWidget::~ViewportWidget()
     delete m_sketchGrid;
 }
 
+void ViewportWidget::setDocument(Document* document)
+{
+    m_document = document;
+}
+
 void ViewportWidget::initializeGL()
 {
     initializeOpenGLFunctions();
@@ -61,11 +69,12 @@ void ViewportWidget::paintGL()
 
     glViewport(0, 0, width(), height());
 
+    QPainter painter(this);
     if (m_currentPlane != SketchPlane::NONE) {
-        QPainter painter(this);
         drawAxisLabels(painter, model, projection);
-        painter.end();
     }
+    drawFeatureBrowser(painter);
+    painter.end();
 }
 
 void ViewportWidget::resizeGL(int w, int h)
@@ -181,3 +190,50 @@ void ViewportWidget::drawAxisLabels(QPainter& painter, const QMatrix4x4& modelVi
         drawLabelsForAxis(2); // Z
     }
 }
+
+void ViewportWidget::drawFeatureBrowser(QPainter& painter)
+{
+    if (!m_document) {
+        return;
+    }
+
+    painter.setRenderHint(QPainter::Antialiasing);
+    painter.setFont(QFont("Arial", 10));
+
+    const int padding = 5;
+    const int margin = 10;
+    int x = margin;
+    int y = height() - margin;
+    int lineHeight = painter.fontMetrics().height();
+    const QList<Feature*>& features = m_document->features();
+    QString docName = m_document->fileName();
+
+    int maxWidth = painter.fontMetrics().horizontalAdvance(docName);
+
+    for (const Feature* feature : features) {
+        maxWidth = std::max(maxWidth, painter.fontMetrics().horizontalAdvance("  " + feature->name()));
+    }
+
+    int boxWidth = maxWidth + 2 * padding;
+    int boxHeight = (features.size() + 1) * lineHeight + 2 * padding;
+
+    y -= boxHeight; // Adjust y to be the top of the box
+
+    // Draw transparent background
+    painter.setPen(Qt::NoPen);
+    painter.setBrush(QColor(50, 50, 50, 150));
+    painter.drawRoundedRect(x, y, boxWidth, boxHeight, 3, 3);
+
+    // Draw text
+    painter.setPen(Qt::white);
+    int currentY = y + padding + lineHeight;
+    int textX = x + padding;
+
+    painter.drawText(textX, currentY, docName);
+    currentY += lineHeight;
+
+    for (const Feature* feature : features) {
+        painter.drawText(textX + 10, currentY, feature->name());
+        currentY += lineHeight;
+    }
+}