1 files changed, 51 insertions, 0 deletions
diff --git a/Source/Threading/rand.cpp b/Source/Threading/rand.cpp
new file mode 100644
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--- /dev/null
+++ b/Source/Threading/rand.cpp
@@ -0,0 +1,51 @@
+//-----------------------------------------------------------------------------
+//           Name: rand.cpp
+//      Developer: Wolfire Games LLC
+//         Author: Max Danielsson
+//    Description: This is a threadsafe variant of pcg rand(), which doesn't 
+//                 require a local reseed variable.
+//        License: Read below
+//-----------------------------------------------------------------------------
+//
+//   Copyright 2022 Wolfire Games LLC
+//
+//   Licensed under the Apache License, Version 2.0 (the "License");
+//   you may not use this file except in compliance with the License.
+//   You may obtain a copy of the License at
+//
+//       http://www.apache.org/licenses/LICENSE-2.0
+//
+//   Unless required by applicable law or agreed to in writing, software
+//   distributed under the License is distributed on an "AS IS" BASIS,
+//   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//   See the License for the specific language governing permissions and
+//   limitations under the License.
+//
+//-----------------------------------------------------------------------------
+#include "rand.h"
+
+#include <Utility/pcg_basic.h>
+#include <Internal/integer.h>
+
+#include <cstdlib>
+#include <mutex>
+
+static std::mutex mutex;
+static unsigned int reseed;
+static pcg32_random_t seedr;
+
+void rand_ts_seed(unsigned int seed)
+{
+    mutex.lock();
+    pcg32_srandom_r(&seedr,seed,seed);
+    mutex.unlock();
+}
+
+uint32_t rand_ts()
+{
+    uint32_t v;
+    mutex.lock();
+    v = pcg32_random_r(&seedr);
+    mutex.unlock();
+    return v;
+}