6 files changed, 99 insertions, 0 deletions
diff --git a/src/render/mgl.cpp b/src/render/mgl.cpp
index 875c291f8..c8de23997 100644
--- a/src/render/mgl.cpp
+++ b/src/render/mgl.cpp
@@ -107,6 +107,7 @@ defName(glEndQuery);
 defName(glDeleteQueries);
 defName(glGetQueryObjectiv);
 defName(glGetQueryObjectui64v);
+defName(glTextureSubImage2D);
 
 #ifdef WIN32
 defName(wglGetExtensionsString);
diff --git a/src/render/mgl.h b/src/render/mgl.h
index a5848e906..705c66caa 100644
--- a/src/render/mgl.h
+++ b/src/render/mgl.h
@@ -110,6 +110,7 @@ defNameE(glEndQuery);
 defNameE(glDeleteQueries);
 defNameE(glGetQueryObjectiv);
 defNameE(glGetQueryObjectui64v);
+defNameE(glTextureSubImage2D);
 
 #ifdef WIN32
 defNameE(wglGetExtensionsString);
diff --git a/src/render/mglemu.cpp b/src/render/mglemu.cpp
new file mode 100644
index 000000000..e8e3eca1c
--- /dev/null
+++ b/src/render/mglemu.cpp
@@ -0,0 +1,43 @@
+/*
+ *  The ManaPlus Client
+ *  Copyright (C) 2014  The ManaPlus Developers
+ *
+ *  This file is part of The ManaPlus Client.
+ *
+ *  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
+ *  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, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifdef USE_OPENGL
+
+#include "render/mglemu.h"
+
+#include "resources/openglimagehelper.h"
+
+#include "debug.h"
+
+void APIENTRY emuglTextureSubImage2D(GLuint texture, GLenum target,
+                                     GLint level,
+                                     GLint xoffset, GLint yoffset,
+                                     GLsizei width, GLsizei height,
+                                     GLenum format, GLenum type,
+                                     const void *pixels)
+{
+    OpenGLImageHelper::bindTexture(texture);
+    glTexSubImage2D(target, level,
+        xoffset, yoffset,
+        width, height,
+        format, type, pixels);
+}
+
+#endif
diff --git a/src/render/mglemu.h b/src/render/mglemu.h
new file mode 100644
index 000000000..2be8dfa5b
--- /dev/null
+++ b/src/render/mglemu.h
@@ -0,0 +1,36 @@
+/*
+ *  The ManaPlus Client
+ *  Copyright (C) 2014  The ManaPlus Developers
+ *
+ *  This file is part of The ManaPlus Client.
+ *
+ *  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
+ *  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, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef RENDER_MGLEMU_H
+#define RENDER_MGLEMU_H
+#ifdef USE_OPENGL
+
+#include "render/mgltypes.h"
+
+void APIENTRY emuglTextureSubImage2D(GLuint texture, GLenum target,
+                                     GLint level,
+                                     GLint xoffset, GLint yoffset,
+                                     GLsizei width, GLsizei height,
+                                     GLenum format, GLenum type,
+                                     const void *pixels);
+
+
+#endif  // USE_OPENGL
+#endif  // RENDER_MGLEMU_H
diff --git a/src/render/mglfunctions.h b/src/render/mglfunctions.h
index e68da7f11..59f05e190 100644
--- a/src/render/mglfunctions.h
+++ b/src/render/mglfunctions.h
@@ -43,5 +43,20 @@
     else \
         logger->log(std::string("assigned function: ") + name);
 
+#define assignFunctionEmu(func, name) m##func \
+    = reinterpret_cast<func##_t>(getFunction(name)); \
+    if (m##func == nullptr) \
+    { \
+        m##func = emu##func; \
+        logger->log(std::string("emulated function: ") + name); \
+    } \
+    else \
+    { \
+        logger->log(std::string("assigned function: ") + name); \
+    }
+
+#define emulateFunction(func) m##func = emu##func; \
+    logger->log("emulated function: #func")
+
 #endif  // USE_OPENGL
 #endif  // RENDER_MGLFUNCTIONS_H
diff --git a/src/render/mgltypes.h b/src/render/mgltypes.h
index c95b88dae..24f1e8ca8 100644
--- a/src/render/mgltypes.h
+++ b/src/render/mgltypes.h
@@ -172,6 +172,9 @@ typedef void (APIENTRY *glGetQueryObjectiv_t) (GLuint id,
     GLenum pname, GLint *params);
 typedef void (APIENTRY *glGetQueryObjectui64v_t) (GLuint id,
     GLenum pname, uint64_t *params);
+typedef void (APIENTRY *glTextureSubImage2D_t) (GLuint texture, GLenum target,
+    GLint level, GLint xoffset, GLint yoffset, GLsizei width, GLsizei height,
+    GLenum format, GLenum type, const void *pixels);
 
 // callback
 typedef void (APIENTRY *GLDEBUGPROC_t) (GLenum source, GLenum type, GLuint id,