--- cegui-0.8.7/cegui/include/CEGUI/RendererModules/Ogre/Renderer.h.orig	2016-04-23 20:19:40.000000000 +0200
+++ cegui-0.8.7/cegui/include/CEGUI/RendererModules/Ogre/Renderer.h	2022-03-11 21:36:04.637974284 +0100
@@ -64,13 +64,13 @@
 class Matrix4;
 }
 
-#if (CEGUI_OGRE_VERSION >= (2 << 16))
+#if (CEGUI_OGRE_VERSION >= (20 << 16))
 // The new Ogre Compositor2 system has to be used since ViewPorts 
 // no longer have the required functionality
 #define CEGUI_USE_OGRE_COMPOSITOR2
 #endif
 
-#if (CEGUI_OGRE_VERSION >= ((2 << 16) | (1 << 8) | 0))
+#if (CEGUI_OGRE_VERSION >= ((20 << 16) | (1 << 8) | 0))
 // The HLMS has to be used since fixed pipeline is disabled
 #define CEGUI_USE_OGRE_HLMS
 #include <OgreRenderOperation.h>
--- cegui-0.8.7/cegui/src/RendererModules/Ogre/Texture.cpp.orig	2022-03-12 09:40:45.000000000 +0100
+++ cegui-0.8.7/cegui/src/RendererModules/Ogre/Texture.cpp	2022-03-12 09:43:34.620043093 +0100
@@ -24,10 +24,12 @@
  *   ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  *   OTHER DEALINGS IN THE SOFTWARE.
  ***************************************************************************/
+#include <sstream>
 #include "CEGUI/RendererModules/Ogre/Texture.h"
 #include "CEGUI/Exceptions.h"
 #include "CEGUI/System.h"
 #include "CEGUI/RendererModules/Ogre/ImageCodec.h"
+#include <OgrePrerequisites.h>
 #include <OgreTextureManager.h>
 #include <OgreHardwarePixelBuffer.h>