Caching index buffers.

src/xenia/gpu/buffer_cache.cc

@@ -0,0 +1,57 @@
+/**
+ ******************************************************************************
+ * Xenia : Xbox 360 Emulator Research Project                                 *
+ ******************************************************************************
+ * Copyright 2014 Ben Vanik. All rights reserved.                             *
+ * Released under the BSD license - see LICENSE in the root for more details. *
+ ******************************************************************************
+ */
+
+#include <xenia/gpu/buffer_cache.h>
+
+#include <xenia/gpu/buffer.h>
+
+
+using namespace std;
+using namespace xe;
+using namespace xe::gpu;
+using namespace xe::gpu::xenos;
+
+
+BufferCache::BufferCache() {
+}
+
+BufferCache::~BufferCache() {
+  Clear();
+}
+
+IndexBuffer* BufferCache::FetchIndexBuffer(
+    const IndexBufferInfo& info,
+    const uint8_t* src_ptr, size_t length) {
+  size_t key = hash_combine(info.endianness, info.index_32bit, info.index_count, info.index_size);
+  size_t hash = xe_hash64(src_ptr, length);
+  auto it = index_buffer_map_.find(key);
+  if (it != index_buffer_map_.end()) {
+    if (hash == it->second->hash()) {
+      return it->second;
+    } else {
+      return it->second->FetchDirty(hash) ? it->second : nullptr;
+    }
+  } else {
+    auto buffer = CreateIndexBuffer(info, src_ptr, length);
+    index_buffer_map_.insert({ key, buffer });
+    if (!buffer->FetchNew(hash)) {
+      return nullptr;
+    }
+    return buffer;
+  }
+}
+
+void BufferCache::Clear() {
+  for (auto it = index_buffer_map_.begin();
+       it != index_buffer_map_.end(); ++it) {
+    auto buffer = it->second;
+    delete buffer;
+  }
+  index_buffer_map_.clear();
+}