Define MAGNUM_TARGET_GLES3 if targetting ES and not ES2.

Makes it easier to disable parts of the code than with this. And this
would also not be future-proof:

    defined(MAGNUM_TARGET_GLES) && !defined(MAGNUM_TARGET_GLES2)

CMakeLists.txt

@@ -86,9 +86,11 @@ endif()
 # Configuration variables (saved later to corradeConfigure.h)
 if(TARGET_GLES)
     set(MAGNUM_TARGET_GLES 1)
-endif()
+    if(TARGET_GLES2)
-if(TARGET_GLES2)
+        set(MAGNUM_TARGET_GLES2 1)
-    set(MAGNUM_TARGET_GLES2 1)
+    else()
+        set(MAGNUM_TARGET_GLES3 1)
+    endif()
 endif()
 if(TARGET_DESKTOP_GLES)
     set(MAGNUM_TARGET_DESKTOP_GLES 1)

doc/cmake.dox

@@ -97,6 +97,7 @@ are also available as preprocessor variables if including Magnum.h:
 
 - `MAGNUM_TARGET_GLES` -- Defined if compiled for OpenGL ES
 - `MAGNUM_TARGET_GLES2` -- Defined if compiled for OpenGL ES 2.0
+- `MAGNUM_TARGET_GLES3` -- Defined if compiled for OpenGL ES 3.0
 - `MAGNUM_TARGET_DESKTOP_GLES` -- Defined if compiled with OpenGL ES emulation
   on desktop OpenGL
 - `MAGNUM_TARGET_NACL` -- Defined if compiled for Google Chrome Native Client

modules/FindMagnum.cmake

@@ -47,6 +47,7 @@
 # Features of found Magnum library are exposed in these variables:
 #  MAGNUM_TARGET_GLES   - Defined if compiled for OpenGL ES
 #  MAGNUM_TARGET_GLES2  - Defined if compiled for OpenGL ES 2.0
+#  MAGNUM_TARGET_GLES3  - Defined if compiled for OpenGL ES 3.0
 #  MAGNUM_TARGET_DESKTOP_GLES - Defined if compiled with OpenGL ES
 #   emulation on desktop OpenGL
 #  MAGNUM_TARGET_NACL   - Defined if compiled for Google Chrome Native
@@ -119,6 +120,10 @@ string(FIND "${_magnumConfigure}" "#define MAGNUM_TARGET_GLES2" _TARGET_GLES2)
 if(NOT _TARGET_GLES2 EQUAL -1)
     set(MAGNUM_TARGET_GLES2 1)
 endif()
+string(FIND "${_magnumConfigure}" "#define MAGNUM_TARGET_GLES3" _TARGET_GLES3)
+if(NOT _TARGET_GLES3 EQUAL -1)
+    set(MAGNUM_TARGET_GLES3 1)
+endif()
 string(FIND "${_magnumConfigure}" "#define MAGNUM_TARGET_NACL" _TARGET_NACL)
 if(NOT _TARGET_NACL EQUAL -1)
     set(MAGNUM_TARGET_NACL 1)

src/Magnum.h

@@ -74,7 +74,8 @@ using Corrade::Utility::Error;
 
 `MAGNUM_TARGET_GLES` is defined if the engine is built for OpenGL ES 3.0 or
 OpenGL ES 2.0.
-@see @ref MAGNUM_TARGET_GLES_ "MAGNUM_TARGET_GLES",
+@see @ref MAGNUM_TARGET_GLES2_ "MAGNUM_TARGET_GLES2",
+    @ref MAGNUM_TARGET_GLES3_ "MAGNUM_TARGET_GLES3",
     @ref MAGNUM_TARGET_DESKTOP_GLES_ "MAGNUM_TARGET_DESKTOP_GLES",
     @ref MAGNUM_TARGET_NACL_ "MAGNUM_TARGET_NACL", @ref building
 */
@@ -85,11 +86,23 @@ OpenGL ES 2.0.
 
 `MAGNUM_TARGET_GLES2` is defined if the engine is built for OpenGL ES 2.0.
 Implies also @ref MAGNUM_TARGET_GLES_ "MAGNUM_TARGET_GLES".
-@see @ref MAGNUM_TARGET_DESKTOP_GLES_ "MAGNUM_TARGET_DESKTOP_GLES",
+@see @ref MAGNUM_TARGET_GLES3_ "MAGNUM_TARGET_GLES3",
+    @ref MAGNUM_TARGET_DESKTOP_GLES_ "MAGNUM_TARGET_DESKTOP_GLES",
     @ref MAGNUM_TARGET_NACL_ "MAGNUM_TARGET_NACL", @ref building
 */
 #define MAGNUM_TARGET_GLES2_
 
+/**
+@brief OpenGL ES 3.0 target.
+
+`MAGNUM_TARGET_GLES3` is defined if the engine is built for OpenGL ES 3.0.
+Implies also @ref MAGNUM_TARGET_GLES_ "MAGNUM_TARGET_GLES".
+@see @ref MAGNUM_TARGET_GLES2_ "MAGNUM_TARGET_GLES2",
+    @ref MAGNUM_TARGET_DESKTOP_GLES_ "MAGNUM_TARGET_DESKTOP_GLES",
+    @ref MAGNUM_TARGET_NACL_ "MAGNUM_TARGET_NACL", @ref building
+*/
+#define MAGNUM_TARGET_GLES3_
+
 /**
 @brief Desktop emulation of OpenGL ES target
 

src/magnumConfigure.h.cmake

@@ -24,6 +24,7 @@
 
 #cmakedefine MAGNUM_TARGET_GLES
 #cmakedefine MAGNUM_TARGET_GLES2
+#cmakedefine MAGNUM_TARGET_GLES3
 #cmakedefine MAGNUM_TARGET_DESKTOP_GLES
 #cmakedefine MAGNUM_TARGET_NACL
 #cmakedefine MAGNUM_USE_HARFBUZZ