Merge pull request #7584 from DonLakeFlyer/VideoItemCrash

Video item crash

ChangeLog.md

@@ -9,6 +9,7 @@ Note: This file only contains high level features or important fixes.
 * Major rewrite and bug fix pass through Structure Scan. Previous version had such bad problems that it can no longer be supported. Plans with Structure Scan will need to be recreated. New QGC will not load old Structure Scan plans.
 
 ### 3.5.4 - Not yet released
+* Guard against null geometry coming from gstreamer which can cause crashes
 * Add .apj file selection support to custom firmware flash
 
 ### 3.5.3 - Stable

src/VideoStreaming/VideoItem.cc

@@ -78,6 +78,17 @@ void VideoItem::setSurface(VideoSurface *surface)
 }
 
 #if defined(QGC_GST_STREAMING)
+QSGGeometry* VideoItem::_createDefaultGeometry(QRectF& rectBound)
+{
+	QSGGeometry *geometry = new QSGGeometry(QSGGeometry::defaultAttributes_Point2D(), 4);
+	geometry->vertexDataAsPoint2D()[0].set(rectBound.x(), rectBound.y());
+	geometry->vertexDataAsPoint2D()[1].set(rectBound.x(), rectBound.height());
+	geometry->vertexDataAsPoint2D()[2].set(rectBound.width(), rectBound.y());
+	geometry->vertexDataAsPoint2D()[3].set(rectBound.width(), rectBound.height());
+
+	return geometry;
+}
+
 QSGNode* VideoItem::updatePaintNode(QSGNode *oldNode, UpdatePaintNodeData*)
 {
     QRectF r = boundingRect();
@@ -103,19 +114,22 @@ QSGNode* VideoItem::updatePaintNode(QSGNode *oldNode, UpdatePaintNodeData*)
             newNode = oldNode;
         }
         if (r != _data->targetArea) {
-            QSGGeometry *geometry = new QSGGeometry(QSGGeometry::defaultAttributes_Point2D(), 4);
-            geometry->vertexDataAsPoint2D()[0].set(r.x(), r.y());
-            geometry->vertexDataAsPoint2D()[1].set(r.x(), r.height());
-            geometry->vertexDataAsPoint2D()[2].set(r.width(), r.y());
-            geometry->vertexDataAsPoint2D()[3].set(r.width(), r.height());
             QSGGeometryNode *node = static_cast<QSGGeometryNode*>(newNode);
-            node->setGeometry(geometry);
+			node->setGeometry(_createDefaultGeometry(r));
             _data->targetArea = r;
         }
     } else {
         g_signal_emit_by_name(_data->surface.data()->_data->videoSink, "update-node", (void*)oldNode, r.x(), r.y(), r.width(), r.height(), (void**)&newNode);
     }
 
+	// Sometimes we can still end up here with no geometry when gstreamer fails to create it for whatever reason. If that happens it can
+	// cause crashes.
+	QSGGeometryNode *node = static_cast<QSGGeometryNode*>(newNode);
+	if (node->geometry() == nullptr) {
+		qDebug() << "Creating default geom";
+		node->setGeometry(_createDefaultGeometry(r));
+	}
+
     return newNode;
 }
 #endif

src/VideoStreaming/VideoItem.h

@@ -19,6 +19,8 @@
 #include <QtQuick/QQuickItem>
 #include "VideoSurface.h"
 
+class QSGGeometry;
+
 class VideoItem : public QQuickItem
 {
     Q_OBJECT
@@ -40,6 +42,8 @@ protected:
 
 private:
 #if defined(QGC_GST_STREAMING)
+	QSGGeometry* _createDefaultGeometry(QRectF& rectBound);
+	
     struct Private;
     Private* const _data;
 #endif