From cdd79e605c2ecc4d28548cb67ed61f1366e9a0fb Mon Sep 17 00:00:00 2001
From: milek7 <me@milek7.pl>
Date: Sun, 21 Oct 2018 00:38:39 +0200
Subject: [PATCH] add gl::fence

---
 CMakeLists.txt |  1 +
 gl/fence.cpp   | 18 ++++++++++++++++++
 gl/fence.h     | 15 +++++++++++++++
 3 files changed, 34 insertions(+)
 create mode 100644 gl/fence.cpp
 create mode 100644 gl/fence.h

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 798a6646..3628c5d7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -108,6 +108,7 @@ set(SOURCES
 "gl/cubemap.cpp"
 "gl/glsl_common.cpp"
 "gl/buffer.cpp"
+"gl/fence.cpp"
 
 "imgui/imgui.cpp"
 "imgui/imgui_demo.cpp"
diff --git a/gl/fence.cpp b/gl/fence.cpp
new file mode 100644
index 00000000..47650068
--- /dev/null
+++ b/gl/fence.cpp
@@ -0,0 +1,18 @@
+#include "fence.h"
+
+gl::fence::fence()
+{
+    sync = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
+}
+
+gl::fence::~fence()
+{
+    glDeleteSync(sync);
+}
+
+bool gl::fence::is_signalled()
+{
+    GLint val;
+    glGetSynciv(sync, GL_SYNC_STATUS, 1, &val);
+    return val == GL_SIGNALED;
+}
diff --git a/gl/fence.h b/gl/fence.h
new file mode 100644
index 00000000..cc5cd09e
--- /dev/null
+++ b/gl/fence.h
@@ -0,0 +1,15 @@
+#include "object.h"
+
+namespace gl
+{
+    class fence
+    {
+        GLsync sync;
+
+    public:
+        fence();
+        ~fence();
+
+        bool is_signalled();
+    };
+}