CurveRenderer: Don't spend time populating unused listHEADdev

When the debug wireframe is disabled, we would still populate
the wireframe vertices, even though these are never read. This
shows up as a small hotspot in valgrind and skipping it
gives a small performance improvement.

Pick-to: 6.10
Change-Id: I51ef403f088154a99c7335356655d3f2cc17b4de
Reviewed-by: Eirik Aavitsland <[email protected]>

1 files changed, 8 insertions, 6 deletions

diff --git a/src/quickshapes/qquickshapecurverenderer.cpp b/src/quickshapes/qquickshapecurverenderer.cpp
index 760224d21e..eefe9da169 100644
--- a/src/quickshapes/qquickshapecurverenderer.cpp
+++ b/src/quickshapes/qquickshapecurverenderer.cpp
@@ -763,12 +763,13 @@ QQuickShapeCurveRenderer::NodeList QQuickShapeCurveRenderer::addCurveStrokeNodes
 
     static const int subdivisions = qEnvironmentVariable("QT_QUICKSHAPES_STROKE_SUBDIVISIONS", QStringLiteral("3")).toInt();
 
+    const bool wireFrame = debugVisualization() & DebugWireframe;
     QSGCurveProcessor::processStroke(path,
                                      pen.miterLimit(),
                                      penWidth,
                                      pen.joinStyle(),
                                      pen.capStyle(),
-                                     [&wfVertices, &node](const std::array<QVector2D, 3> &s,
+                                     [&wfVertices, &node, &wireFrame](const std::array<QVector2D, 3> &s,
                                                           const std::array<QVector2D, 3> &p,
                                                           const std::array<QVector2D, 3> &n,
                                                           QSGCurveStrokeNode::TriangleFlags flags)
@@ -781,9 +782,11 @@ QQuickShapeCurveRenderer::NodeList QQuickShapeCurveRenderer::addCurveStrokeNodes
                                          else
                                              node->appendTriangle(s, p, n);
 
-                                         wfVertices.append({p0.x(), p0.y(), 1.0f, 0.0f, 0.0f});
-                                         wfVertices.append({p1.x(), p1.y(), 0.0f, 1.0f, 0.0f});
-                                         wfVertices.append({p2.x(), p2.y(), 0.0f, 0.0f, 1.0f});
+                                         if (Q_UNLIKELY(wireFrame)) {
+                                             wfVertices.append({p0.x(), p0.y(), 1.0f, 0.0f, 0.0f});
+                                             wfVertices.append({p1.x(), p1.y(), 0.0f, 1.0f, 0.0f});
+                                             wfVertices.append({p2.x(), p2.y(), 0.0f, 0.0f, 1.0f});
+                                         }
                                     },
                                     subdivisions);
 
@@ -794,8 +797,7 @@ QQuickShapeCurveRenderer::NodeList QQuickShapeCurveRenderer::addCurveStrokeNodes
     node->cookGeometry();
     ret.append(node);
 
-    const bool wireFrame = debugVisualization() & DebugWireframe;
-    if (wireFrame) {
+    if (Q_UNLIKELY(wireFrame)) {
         QQuickShapeWireFrameNode *wfNode = new QQuickShapeWireFrameNode;
 
         QSGGeometry *wfg = new QSGGeometry(QQuickShapeWireFrameNode::attributes(),