Fix boundingVolumePositionAttribute handling

This patch fixes a crash when using setBoundingVolumePositionAttribute
on geometries with indexBuffer.

Fixes: QTBUG-85131
Change-Id: Ib5d5e71412daf3b032fc85105cab858c3a937174
Reviewed-by: Mike Krus <mike.krus@kdab.com>
(cherry picked from commit 449d4bcf18f723c70f3f040df49573360d9017a0)
Reviewed-by: Volker Enderlein <volker.enderlein@ifm-chemnitz.de>

1 files changed, 31 insertions, 27 deletions

diff --git a/src/render/jobs/calcboundingvolumejob.cpp b/src/render/jobs/calcboundingvolumejob.cpp
index 842b301c9..dc58eb6b9 100644
--- a/src/render/jobs/calcboundingvolumejob.cpp
+++ b/src/render/jobs/calcboundingvolumejob.cpp
@@ -241,9 +241,10 @@ BoundingVolumeComputeData findBoundingVolumeComputeData(NodeManagers *manager, E
     int drawVertexCount = gRenderer->vertexCount(); // may be 0, gets changed below if so
 
     Qt3DRender::Render::Attribute *positionAttribute = manager->lookupResource<Attribute, AttributeManager>(geom->boundingPositionAttribute());
+    bool hasBoundingVolumePositionAttribute = positionAttribute != nullptr;
 
     // Use the default position attribute if attribute is null
-    if (!positionAttribute) {
+    if (!hasBoundingVolumePositionAttribute) {
         const auto attrIds = geom->attributes();
         for (const Qt3DCore::QNodeId &attrId : attrIds) {
             positionAttribute = manager->lookupResource<Attribute, AttributeManager>(attrId);
@@ -271,37 +272,40 @@ BoundingVolumeComputeData findBoundingVolumeComputeData(NodeManagers *manager, E
     // Check if there is an index attribute.
     Qt3DRender::Render::Attribute *indexAttribute = nullptr;
     Buffer *indexBuf = nullptr;
-    const QVector<Qt3DCore::QNodeId> attributes = geom->attributes();
-
-    for (Qt3DCore::QNodeId attrNodeId : attributes) {
-        Qt3DRender::Render::Attribute *attr = manager->lookupResource<Attribute, AttributeManager>(attrNodeId);
-        if (attr && attr->attributeType() == QAttribute::IndexAttribute) {
-            indexBuf = manager->lookupResource<Buffer, BufferManager>(attr->bufferId());
-            if (indexBuf) {
-                indexAttribute = attr;
-
-                if (!drawVertexCount)
-                    drawVertexCount = indexAttribute->count();
-
-                const QAttribute::VertexBaseType validIndexTypes[] = {
-                    QAttribute::UnsignedShort,
-                    QAttribute::UnsignedInt,
-                    QAttribute::UnsignedByte
-                };
-
-                if (std::find(std::begin(validIndexTypes),
-                              std::end(validIndexTypes),
-                              indexAttribute->vertexBaseType()) == std::end(validIndexTypes)) {
-                    qWarning() << "findBoundingVolumeComputeData: Unsupported index attribute type" << indexAttribute->name() << indexAttribute->vertexBaseType();
-                    return {};
-                }
 
-                break;
+    if (!hasBoundingVolumePositionAttribute) {
+        const QVector<Qt3DCore::QNodeId> attributes = geom->attributes();
+
+        for (Qt3DCore::QNodeId attrNodeId : attributes) {
+            Qt3DRender::Render::Attribute *attr = manager->lookupResource<Attribute, AttributeManager>(attrNodeId);
+            if (attr && attr->attributeType() == QAttribute::IndexAttribute) {
+                indexBuf = manager->lookupResource<Buffer, BufferManager>(attr->bufferId());
+                if (indexBuf) {
+                    indexAttribute = attr;
+
+                    if (!drawVertexCount)
+                        drawVertexCount = indexAttribute->count();
+
+                    const QAttribute::VertexBaseType validIndexTypes[] = {
+                        QAttribute::UnsignedShort,
+                        QAttribute::UnsignedInt,
+                        QAttribute::UnsignedByte
+                    };
+
+                    if (std::find(std::begin(validIndexTypes),
+                                  std::end(validIndexTypes),
+                                  indexAttribute->vertexBaseType()) == std::end(validIndexTypes)) {
+                        qWarning() << "findBoundingVolumeComputeData: Unsupported index attribute type" << indexAttribute->name() << indexAttribute->vertexBaseType();
+                        return {};
+                    }
+
+                    break;
+                }
             }
         }
     }
 
-    if (!indexAttribute && !drawVertexCount)
+    if (hasBoundingVolumePositionAttribute || (!indexAttribute && !drawVertexCount))
         drawVertexCount = positionAttribute->count();
 
     // Buf will be set to not dirty once it's loaded