Don't expose unneeded ES2 extensions under ES3.

They provide the same or slightly different functionality as is present
in ES3 itself, causing confusion. Fortunately this change required only
one modification in Context test and nowhere else.

src/Context.cpp

@@ -213,6 +213,7 @@ const std::vector<Extension>& Extension::extensions(Version version) {
         _extension(GL,OES,stencil1),
         _extension(GL,OES,stencil4),
         _extension(GL,OES,texture_3D)};
+    #ifdef MAGNUM_TARGET_GLES2
     static const std::vector<Extension> extensionsES300{
         _extension(GL,ANGLE,framebuffer_blit),
         _extension(GL,ANGLE,framebuffer_multisample),
@@ -246,6 +247,7 @@ const std::vector<Extension>& Extension::extensions(Version version) {
         _extension(GL,OES,required_internalformat),
         _extension(GL,OES,surfaceless_context)};            // done
     #endif
+    #endif
 
     switch(version) {
         case Version::None:  return extensions;
@@ -264,7 +266,12 @@ const std::vector<Extension>& Extension::extensions(Version version) {
         case Version::GL440: return extensions440;
         #else
         case Version::GLES200: return empty;
-        case Version::GLES300: return extensionsES300;
+        case Version::GLES300:
+            #ifdef MAGNUM_TARGET_GLES2
+            return extensionsES300;
+            #else
+            return empty;
+            #endif
         #endif
     }
 

src/Extensions.h

@@ -200,56 +200,83 @@ namespace GL {
     #else
     #line 1
     namespace ANGLE {
+        #ifdef MAGNUM_TARGET_GLES2
         _extension(GL,ANGLE,framebuffer_blit,       GLES200, GLES300) // #83
         _extension(GL,ANGLE,framebuffer_multisample, GLES200, GLES300) // #84
         _extension(GL,ANGLE,depth_texture,          GLES200, GLES300) // #138
+        #endif
     } namespace APPLE {
+        #ifdef MAGNUM_TARGET_GLES2
         _extension(GL,APPLE,framebuffer_multisample, GLES200, GLES300) // #78
+        #endif
         _extension(GL,APPLE,texture_format_BGRA8888, GLES200,   None) // #79
     } namespace ARM {
+        #ifdef MAGNUM_TARGET_GLES2
         _extension(GL,ARM,rgba8,                    GLES200, GLES300) // #82
+        #endif
     } namespace CHROMIUM {
         _extension(GL,CHROMIUM,map_sub,             GLES200,    None)
     } namespace EXT {
         _extension(GL,EXT,texture_filter_anisotropic, GLES200,  None) // #41
+        #ifdef MAGNUM_TARGET_GLES2
         _extension(GL,EXT,texture_type_2_10_10_10_REV, GLES200, GLES300) // #42
+        #endif
         _extension(GL,EXT,texture_format_BGRA8888,  GLES200,    None) // #51
+        #ifdef MAGNUM_TARGET_GLES2
         _extension(GL,EXT,discard_framebuffer,      GLES200, GLES300) // #64
         _extension(GL,EXT,blend_minmax,             GLES200, GLES300) // #65
+        #endif
         _extension(GL,EXT,read_format_bgra,         GLES200,    None) // #66
         _extension(GL,EXT,debug_label,              GLES200,    None) // #98
         _extension(GL,EXT,debug_marker,             GLES200,    None) // #99
+        #ifdef MAGNUM_TARGET_GLES2
         _extension(GL,EXT,occlusion_query_boolean,  GLES200, GLES300) // #100
+        #endif
         _extension(GL,EXT,separate_shader_objects,  GLES200,    None) // #101
+        #ifdef MAGNUM_TARGET_GLES2
         _extension(GL,EXT,texture_rg,               GLES200, GLES300) // #103
+        #endif
         _extension(GL,EXT,sRGB,                     GLES200,    None) // #105
         _extension(GL,EXT,multisampled_render_to_texture, GLES200, None) // #106
         _extension(GL,EXT,robustness,               GLES200,    None) // #107
+        #ifdef MAGNUM_TARGET_GLES2
         _extension(GL,EXT,texture_storage,          GLES200, GLES300) // #108
         _extension(GL,EXT,map_buffer_range,         GLES200, GLES300) // #121
+        #endif
         _extension(GL,EXT,disjoint_timer_query,     GLES200,    None) // #150
     } namespace KHR {
         _extension(GL,KHR,debug,                    GLES200,    None) // #118
     } namespace NV {
+        #ifdef MAGNUM_TARGET_GLES2
         _extension(GL,NV,draw_buffers,              GLES200, GLES300) // #91
         _extension(GL,NV,fbo_color_attachments,     GLES200, GLES300) // #92
         _extension(GL,NV,read_buffer,               GLES200, GLES300) // #93
+        #endif
         _extension(GL,NV,read_buffer_front,         GLES200,    None) // #93
         _extension(GL,NV,read_depth,                GLES200,    None) // #94
         _extension(GL,NV,read_stencil,              GLES200,    None) // #94
         _extension(GL,NV,read_depth_stencil,        GLES200,    None) // #94
+        #ifdef MAGNUM_TARGET_GLES2
         _extension(GL,NV,framebuffer_blit,          GLES200, GLES300) // #142
         _extension(GL,NV,framebuffer_multisample,   GLES200, GLES300) // #143
+        #endif
         _extension(GL,NV,texture_border_clamp,      GLES200,    None) // #149
     } namespace OES {
+        #ifdef MAGNUM_TARGET_GLES2
         _extension(GL,OES,depth24,                  GLES200, GLES300) // #24
+        #endif
         _extension(GL,OES,depth32,                  GLES200,    None) // #25
+        #ifdef MAGNUM_TARGET_GLES2
         _extension(GL,OES,element_index_uint,       GLES200, GLES300) // #26
+        #endif
         _extension(GL,OES,mapbuffer,                GLES200,    None) // #29
+        #ifdef MAGNUM_TARGET_GLES2
         _extension(GL,OES,rgb8_rgba8,               GLES200, GLES300) // #30
+        #endif
         _extension(GL,OES,stencil1,                 GLES200,    None) // #31
         _extension(GL,OES,stencil4,                 GLES200,    None) // #32
         _extension(GL,OES,texture_3D,               GLES200,    None) // #34
+        #ifdef MAGNUM_TARGET_GLES2
         _extension(GL,OES,texture_half_float_linear, GLES200, GLES300) // #35
         _extension(GL,OES,texture_float_linear,     GLES200, GLES300) // #35
         _extension(GL,OES,texture_half_float,       GLES200, GLES300) // #36
@@ -261,6 +288,7 @@ namespace GL {
         _extension(GL,OES,vertex_array_object,      GLES200, GLES300) // #71
         _extension(GL,OES,required_internalformat,  GLES200, GLES300) // #115
         _extension(GL,OES,surfaceless_context,      GLES200, GLES300) // #116
+        #endif
     }
     #endif
 }

src/Test/ContextGLTest.cpp

@@ -101,18 +101,15 @@ void ContextGLTest::unsupportedExtension() {
 void ContextGLTest::pastExtension() {
     #ifndef MAGNUM_TARGET_GLES
     if(!Context::current()->isVersionSupported(Version::GL300))
-        CORRADE_SKIP("No already supported extensions exist in OpenGL 2.1");
+        CORRADE_SKIP("No already supported extensions are listed for OpenGL 2.1");
 
     CORRADE_VERIFY(Context::current()->isExtensionSupported<Extensions::GL::APPLE::vertex_array_object>());
     /* No assertion should be fired */
     MAGNUM_ASSERT_EXTENSION_SUPPORTED(Extensions::GL::APPLE::vertex_array_object);
+    #elif defined(MAGNUM_TARGET_GLES2)
+    CORRADE_SKIP("No already supported extensions are listed for OpenGL ES 2.0");
     #else
-    if(!Context::current()->isVersionSupported(Version::GLES300))
+    CORRADE_SKIP("No already supported extensions are listed for OpenGL ES 3.0");
-        CORRADE_SKIP("No already supported extensions exist in OpenGL ES 2.0");
-
-    CORRADE_VERIFY(Context::current()->isExtensionSupported<Extensions::GL::EXT::texture_rg>());
-    /* No assertion should be fired */
-    MAGNUM_ASSERT_EXTENSION_SUPPORTED(Extensions::GL::EXT::texture_rg);
     #endif
 }