Repo created

libs/drape/index_storage.cpp

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+#include "drape/index_storage.hpp"
+#include "drape/gl_functions.hpp"
+
+#include <utility>
+
+namespace dp
+{
+IndexStorage::IndexStorage() : m_size(0) {}
+
+IndexStorage::IndexStorage(std::vector<uint32_t> && initial)
+{
+  m_size = (uint32_t)initial.size();
+  if (IsSupported32bit())
+  {
+    m_storage = std::move(initial);
+  }
+  else
+  {
+    // We pack 2 uint16_t indices into single m_storage element.
+    // Every element of "initial" vector is a single index.
+    m_storage.resize(GetStorageSize(m_size));
+    for (size_t i = 0; i < initial.size(); i++)
+    {
+      uint16_t * ptr = reinterpret_cast<uint16_t *>(m_storage.data()) + i;
+      *ptr = (uint16_t)initial[i];
+    }
+  }
+}
+
+void IndexStorage::Resize(uint32_t size)
+{
+  m_size = size;
+  m_storage.resize(GetStorageSize(m_size));
+}
+
+uint32_t IndexStorage::Size() const
+{
+  return m_size;
+}
+
+void * IndexStorage::GetRaw(uint32_t offsetInElements)
+{
+  if (IsSupported32bit())
+    return &m_storage[offsetInElements];
+
+  return reinterpret_cast<uint16_t *>(m_storage.data()) + offsetInElements;
+}
+
+void const * IndexStorage::GetRawConst() const
+{
+  return static_cast<void const *>(m_storage.data());
+}
+
+bool IndexStorage::IsSupported32bit()
+{
+  // We do not use 32-bit indices now to reduce size of index buffers.
+  static bool const supports32Bit = false;
+  return supports32Bit;
+}
+
+uint32_t IndexStorage::SizeOfIndex()
+{
+  return IsSupported32bit() ? sizeof(uint32_t) : sizeof(uint16_t);
+}
+
+uint32_t IndexStorage::GetStorageSize(uint32_t elementsCount) const
+{
+  return IsSupported32bit() ? elementsCount : (elementsCount / 2 + 1);
+}
+}  // namespace dp