From ad4b40fad653b73ca8a79b13161ff43e159b3ef4 Mon Sep 17 00:00:00 2001
From: Quantum <quantum2048@gmail.com>
Date: Thu, 30 Sep 2021 06:14:25 -0400
Subject: [PATCH] [client] opengl: add gl_dynprocs module

This is similar to egl_dynprocs, except for OpenGL functions.
---
 client/CMakeLists.txt        |  1 +
 client/include/gl_dynprocs.h | 50 +++++++++++++++++++++++++++++++
 client/src/gl_dynprocs.c     | 58 ++++++++++++++++++++++++++++++++++++
 client/src/main.c            |  2 ++
 4 files changed, 111 insertions(+)
 create mode 100644 client/include/gl_dynprocs.h
 create mode 100644 client/src/gl_dynprocs.c

diff --git a/client/CMakeLists.txt b/client/CMakeLists.txt
index 8f823038..498844d3 100644
--- a/client/CMakeLists.txt
+++ b/client/CMakeLists.txt
@@ -111,6 +111,7 @@ set(SOURCES
 	src/util.c
 	src/clipboard.c
 	src/kb.c
+	src/gl_dynprocs.c
 	src/egl_dynprocs.c
 	src/eglutil.c
 	src/overlay_utils.c
diff --git a/client/include/gl_dynprocs.h b/client/include/gl_dynprocs.h
new file mode 100644
index 00000000..27f3bbff
--- /dev/null
+++ b/client/include/gl_dynprocs.h
@@ -0,0 +1,50 @@
+/**
+ * Looking Glass
+ * Copyright © 2017-2021 The Looking Glass Authors
+ * https://looking-glass.io
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef _H_LG_GL_DYNPROCS_
+#define _H_LG_GL_DYNPROCS_
+#ifdef ENABLE_OPENGL
+
+#include <GL/gl.h>
+#include <GL/glext.h>
+
+struct GLDynProcs
+{
+  PFNGLGENBUFFERSPROC     glGenBuffers;
+  PFNGLBINDBUFFERPROC     glBindBuffer;
+  PFNGLBUFFERDATAPROC     glBufferData;
+  PFNGLBUFFERSUBDATAPROC  glBufferSubData;
+  PFNGLDELETEBUFFERSPROC  glDeleteBuffers;
+  PFNGLISSYNCPROC         glIsSync;
+  PFNGLFENCESYNCPROC      glFenceSync;
+  PFNGLCLIENTWAITSYNCPROC glClientWaitSync;
+  PFNGLDELETESYNCPROC     glDeleteSync;
+  PFNGLGENERATEMIPMAPPROC glGenerateMipmap;
+};
+
+extern struct GLDynProcs g_gl_dynProcs;
+
+void gl_dynProcsInit(void);
+
+#else
+  #define gl_dynProcsInit(...)
+#endif
+
+#endif // _H_LG_GL_DYNPROCS_
diff --git a/client/src/gl_dynprocs.c b/client/src/gl_dynprocs.c
new file mode 100644
index 00000000..2fc7e64b
--- /dev/null
+++ b/client/src/gl_dynprocs.c
@@ -0,0 +1,58 @@
+/**
+ * Looking Glass
+ * Copyright © 2017-2021 The Looking Glass Authors
+ * https://looking-glass.io
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifdef ENABLE_OPENGL
+
+#include "gl_dynprocs.h"
+#include <GL/glx.h>
+
+struct GLDynProcs g_gl_dynProcs = {0};
+
+
+static void * getProcAddressGL(const char * name)
+{
+  return (void *) glXGetProcAddressARB((const GLubyte *) name);
+}
+
+static void * setProcAddressGL2(const char * name, const char * backup)
+{
+  void * func = getProcAddressGL(name);
+  return func ? func : getProcAddressGL(backup);
+}
+
+void gl_dynProcsInit(void)
+{
+  g_gl_dynProcs.glGenBuffers    = setProcAddressGL2("glGenBuffers", "glGenBuffersARB");
+  g_gl_dynProcs.glBindBuffer    = setProcAddressGL2("glBindBuffer", "glBindBufferARB");
+  g_gl_dynProcs.glBufferData    = setProcAddressGL2("glBufferData", "glBufferDataARB");
+  g_gl_dynProcs.glBufferSubData = setProcAddressGL2("glBufferSubData", "glBufferSubDataARB");
+  g_gl_dynProcs.glDeleteBuffers = setProcAddressGL2("glDeleteBuffers", "glDeleteBuffersARB");
+
+  g_gl_dynProcs.glIsSync         = getProcAddressGL("glIsSync");
+  g_gl_dynProcs.glFenceSync      = getProcAddressGL("glFenceSync");
+  g_gl_dynProcs.glClientWaitSync = getProcAddressGL("glClientWaitSync");
+  g_gl_dynProcs.glDeleteSync     = getProcAddressGL("glDeleteSync");
+
+  g_gl_dynProcs.glGenerateMipmap = getProcAddressGL("glGenerateMipmap");
+  if (!g_gl_dynProcs.glGenerateMipmap)
+    g_gl_dynProcs.glGenerateMipmap = getProcAddressGL("glGenerateMipmapEXT");
+};
+
+#endif
diff --git a/client/src/main.c b/client/src/main.c
index c26fec72..1e5e23ac 100644
--- a/client/src/main.c
+++ b/client/src/main.c
@@ -58,6 +58,7 @@
 #include "kb.h"
 #include "ll.h"
 #include "egl_dynprocs.h"
+#include "gl_dynprocs.h"
 #include "overlays.h"
 #include "overlay_utils.h"
 #include "util.h"
@@ -1297,6 +1298,7 @@ int main(int argc, char * argv[])
   config_init();
   ivshmemOptionsInit();
   egl_dynProcsInit();
+  gl_dynProcsInit();
 
   g_state.overlays = ll_new();
   app_registerOverlay(&LGOverlayConfig, NULL);