diff --git a/MobileGL/MG_Impl/GLImpl/Framebuffer/GL_Framebuffer.cpp b/MobileGL/MG_Impl/GLImpl/Framebuffer/GL_Framebuffer.cpp
index d590ba4f..6419350a 100644
--- a/MobileGL/MG_Impl/GLImpl/Framebuffer/GL_Framebuffer.cpp
+++ b/MobileGL/MG_Impl/GLImpl/Framebuffer/GL_Framebuffer.cpp
@@ -304,6 +304,10 @@ namespace MobileGL {
             }
         }
 
+        void ReadBuffer_State(GLenum src) {
+            // TODO: implement
+        }
+
         void DeleteRenderbuffers_State(GLsizei n, const GLuint* renderbuffers) {
             if (n < 0) {
                 MG_State::pGLContext->RecordError(
@@ -575,6 +579,10 @@ namespace MobileGL {
             DrawBuffers_State(n, bufs);
         }
 
+        void ReadBuffer(GLenum src) {
+            ReadBuffer_State(src);
+        }
+
         void DeleteRenderbuffers(GLsizei n, const GLuint* renderbuffers) {
             DeleteRenderbuffers_State(n, renderbuffers);
         }
diff --git a/MobileGL/MG_Impl/GLImpl/Framebuffer/GL_Framebuffer.h b/MobileGL/MG_Impl/GLImpl/Framebuffer/GL_Framebuffer.h
index b06af10b..b332608c 100644
--- a/MobileGL/MG_Impl/GLImpl/Framebuffer/GL_Framebuffer.h
+++ b/MobileGL/MG_Impl/GLImpl/Framebuffer/GL_Framebuffer.h
@@ -46,6 +46,7 @@ namespace MobileGL {
         void FramebufferRenderbuffer(GLenum target, GLenum attachment, GLenum renderbuffertarget, GLuint renderbuffer);
         void DrawBuffer(GLenum buf);
         void DrawBuffers(GLsizei n, const GLenum* bufs);
+        void ReadBuffer(GLenum src);
         void DeleteRenderbuffers(GLsizei n, const GLuint* renderbuffers);
         void DeleteFramebuffers(GLsizei n, const GLuint* framebuffers);
         GLenum CheckFramebufferStatus(GLenum target);
diff --git a/MobileGL/MG_Impl/GLImpl/RenderState/GL_RenderState.cpp b/MobileGL/MG_Impl/GLImpl/RenderState/GL_RenderState.cpp
index 540fd0a6..57548582 100644
--- a/MobileGL/MG_Impl/GLImpl/RenderState/GL_RenderState.cpp
+++ b/MobileGL/MG_Impl/GLImpl/RenderState/GL_RenderState.cpp
@@ -241,10 +241,6 @@ namespace MobileGL {
             // TODO: implement
         }
 
-        void ReadBuffer_State(GLenum src) {
-            // TODO: implement
-        }
-
         void ClearStencil_State(GLint s) {
             // TODO: implement
         }
@@ -390,10 +386,6 @@ namespace MobileGL {
             BlendColor_State(red, green, blue, alpha);
         }
 
-        void ReadBuffer(GLenum src) {
-            ReadBuffer_State(src);
-        }
-
         void ClearStencil(GLint s) {
             ClearStencil_State(s);
         }
diff --git a/MobileGL/MG_Impl/GLImpl/RenderState/GL_RenderState.h b/MobileGL/MG_Impl/GLImpl/RenderState/GL_RenderState.h
index 9d35e01c..0dac02b3 100644
--- a/MobileGL/MG_Impl/GLImpl/RenderState/GL_RenderState.h
+++ b/MobileGL/MG_Impl/GLImpl/RenderState/GL_RenderState.h
@@ -45,7 +45,6 @@ namespace MobileGL {
         void BlendFuncSeparate(GLenum sfactorRGB, GLenum dfactorRGB, GLenum sfactorAlpha, GLenum dfactorAlpha);
         void BlendEquation(GLenum mode);
         void BlendColor(GLfloat red, GLfloat green, GLfloat blue, GLfloat alpha);
-        void ReadBuffer(GLenum src);
         void ClearStencil(GLint s);
         void ClearDepth(GLclampd depth);
         void ClearColor(GLfloat red, GLfloat green, GLfloat blue, GLfloat alpha);