ObjLoader: actually check for the indices' values

The decision whether we can use ushort instead of uint for the entries
in the index buffer depends on the value of each entry, not on
how many entries (indices) we have. Clean up the related code.

Task-number: QTBUG-44089
Change-Id: Id8e1cb422c1bd3a84f8964864a41cc4784edce61
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>

1 files changed, 7 insertions, 7 deletions

diff --git a/src/render/io/objloader.cpp b/src/render/io/objloader.cpp
index 686a9d5f0..aaecac9e8 100644
--- a/src/render/io/objloader.cpp
+++ b/src/render/io/objloader.cpp
@@ -56,6 +56,8 @@
 #include <Qt3DRender/qattribute.h>
 #include <Qt3DRender/qbuffer.h>
 
+#include <algorithm>
+
 QT_BEGIN_NAMESPACE
 
 namespace Qt3DRender {
@@ -405,19 +407,17 @@ QGeometry *ObjLoader::geometry() const
 
     QByteArray indexBytes;
     QAttribute::VertexBaseType ty;
-    if (m_indices.size() < 65536) {
+    if (std::all_of(m_indices.cbegin(), m_indices.cend(), [](unsigned int index) { return index < 65536; })) {
         // we can use USHORT
         ty = QAttribute::UnsignedShort;
         indexBytes.resize(m_indices.size() * sizeof(quint16));
-        quint16* usptr = reinterpret_cast<quint16*>(indexBytes.data());
-        for (int i=0; i<m_indices.size(); ++i)
-            *usptr++ = static_cast<quint16>(m_indices.at(i));
+        quint16 *usptr = reinterpret_cast<quint16 *>(indexBytes.data());
+        std::copy(m_indices.cbegin(), m_indices.cend(), usptr);
     } else {
-        // use UINT - no conversion needed, but let's ensure int is 32-bit!
+        // use UINT
         ty = QAttribute::UnsignedInt;
-        Q_ASSERT(sizeof(int) == sizeof(quint32));
         indexBytes.resize(m_indices.size() * sizeof(quint32));
-        memcpy(indexBytes.data(), reinterpret_cast<const char*>(m_indices.data()), indexBytes.size());
+        memcpy(indexBytes.data(), reinterpret_cast<const char *>(m_indices.constData()), indexBytes.size());
     }
 
     QBuffer *indexBuffer(new QBuffer(QBuffer::IndexBuffer));