Nothing to see here.

src/Magnum/British.h

@@ -25,7 +25,12 @@
     DEALINGS IN THE SOFTWARE.
 */
 
-/* You bloody hell better not tell anybody you bumped into this, aye? Ta! */
+/* You bloody hell better not tell anybody you bumped into this, aye? Ta!
+
+   This file, and everything wrapped in #ifdef Magnum_British_h, is only
+   allowed to be edited on April 1st. I don't make the rules. All such changes
+   should also be ABI-independent, so it's effectively limited to enum aliases
+   and typedefs. */
 
 #include "Magnum/Magnum.h"
 

src/Magnum/GL/AbstractFramebuffer.h

@@ -45,9 +45,12 @@ namespace Magnum { namespace GL {
 @m_enum_values_as_keywords
 */
 enum class FramebufferClear: GLbitfield {
-    Color = GL_COLOR_BUFFER_BIT,    /**< Color buffer */
+    Color = GL_COLOR_BUFFER_BIT,        /**< Color buffer */
-    Depth = GL_DEPTH_BUFFER_BIT,    /**< Depth buffer */
+    Depth = GL_DEPTH_BUFFER_BIT,        /**< Depth buffer */
-    Stencil = GL_STENCIL_BUFFER_BIT /**< Stencil buffer */
+    Stencil = GL_STENCIL_BUFFER_BIT,    /**< Stencil buffer */
+    #ifdef Magnum_British_h
+    Colour = Color
+    #endif
 };
 
 /**
@@ -74,9 +77,12 @@ typedef Containers::EnumSet<FramebufferClear> FramebufferClearMask;
 @requires_webgl20 Framebuffer blit is not available in WebGL 1.0.
 */
 enum class FramebufferBlit: GLbitfield {
-    Color = GL_COLOR_BUFFER_BIT,    /**< Color buffer */
+    Color = GL_COLOR_BUFFER_BIT,        /**< Color buffer */
-    Depth = GL_DEPTH_BUFFER_BIT,    /**< Depth buffer */
+    Depth = GL_DEPTH_BUFFER_BIT,        /**< Depth buffer */
-    Stencil = GL_STENCIL_BUFFER_BIT /**< Stencil buffer */
+    Stencil = GL_STENCIL_BUFFER_BIT,    /**< Stencil buffer */
+    #ifdef Magnum_British_h
+    Colour = Color
+    #endif
 };
 
 /**

src/Magnum/GL/DefaultFramebuffer.h

@@ -301,9 +301,13 @@ class MAGNUM_GL_EXPORT DefaultFramebuffer: public AbstractFramebuffer {
 
             /** Invalidate stencil buffer. */
             #ifndef MAGNUM_TARGET_GLES2
-            Stencil = GL_STENCIL
+            Stencil = GL_STENCIL,
             #else
-            Stencil = GL_STENCIL_EXT
+            Stencil = GL_STENCIL_EXT,
+            #endif
+
+            #ifdef Magnum_British_h
+            Colour = Color
             #endif
         };
         #endif

src/Magnum/GL/Framebuffer.h

@@ -146,6 +146,10 @@ class MAGNUM_GL_EXPORT Framebuffer: public AbstractFramebuffer, public AbstractO
                 GLenum attachment;
         };
 
+        #ifdef Magnum_British_h
+        typedef ColorAttachment ColurAttachment;
+        #endif
+
         /**
          * @brief Draw attachment
          *

src/Magnum/GL/Renderer.h

@@ -1667,7 +1667,13 @@ class MAGNUM_GL_EXPORT Renderer {
              * @requires_webgl_extension Extension
              *      @webgl_extension{WEBGL,blend_equation_advanced_coherent}
              */
-            HslLuminosity = GL_HSL_LUMINOSITY_KHR
+            HslLuminosity = GL_HSL_LUMINOSITY_KHR,
+
+            #ifdef Magnum_British_h
+            ColourDodge = ColorDodge,
+            ColourBurn = ColorBurn,
+            HslColour = HslColor
+            #endif
         };
 
         /**
@@ -1812,7 +1818,18 @@ class MAGNUM_GL_EXPORT Renderer {
             /**
              * One minus source alpha (@f$ RGB = (1.0 - A_d, 1.0 - A_d, 1.0 - A_d); A = 1.0 - A_d @f$)
              */
-            OneMinusDestinationAlpha = GL_ONE_MINUS_DST_ALPHA
+            OneMinusDestinationAlpha = GL_ONE_MINUS_DST_ALPHA,
+
+            #ifdef Magnum_British_h
+            ConstantColour = ConstantColor,
+            OneMinusConstantColour = OneMinusConstantColor,
+            SourceColour = SourceColor,
+            SecondSourceColour = SecondSourceColor,
+            OneMinusSourceColour = OneMinusSourceColor,
+            OneMinusSecondSourceColour = OneMinusSecondSourceColor,
+            DestinationColour = DestinationColor,
+            OneMinusDestinationColour = OneMinusDestinationColor
+            #endif
         };
 
         /**

src/Magnum/Test/BritishTest.cpp

@@ -0,0 +1,58 @@
+/*
+    This file is part of Magnum.
+
+    Copyright © 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019,
+                2020, 2021, 2022, 2023 Vladimír Vondruš <mosra@centrum.cz>
+
+    Permission is hereby granted, free of charge, to any person obtaining a
+    copy of this software and associated documentation files (the "Software"),
+    to deal in the Software without restriction, including without limitation
+    the rights to use, copy, modify, merge, publish, distribute, sublicense,
+    and/or sell copies of the Software, and to permit persons to whom the
+    Software is furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be included
+    in all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+    THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+    DEALINGS IN THE SOFTWARE.
+*/
+
+#include <Corrade/TestSuite/Tester.h>
+
+#include "Magnum/British.h"
+/* Include all files with functionality wrapped in #ifdef Magnum_British_h
+   here. As all such code should be limited to enum aliases and typedefs, it
+   should be enough to verify it parses correctly. */
+#include "Magnum/Math/Color.h"
+#ifdef MAGNUM_TARGET_GL
+#include "Magnum/GL/DefaultFramebuffer.h"
+#include "Magnum/GL/Framebuffer.h"
+#include "Magnum/GL/Renderer.h"
+#endif
+
+namespace Magnum { namespace Test { namespace {
+
+struct BritishTest: TestSuite::Tester {
+    explicit BritishTest();
+
+    void cheers();
+};
+
+BritishTest::BritishTest() {
+    addTests({&BritishTest::cheers});
+}
+
+void BritishTest::cheers() {
+    Colour3 colour;
+    CORRADE_COMPARE(colour.r(), 0.0f);
+}
+
+}}}
+
+CORRADE_TEST_MAIN(Magnum::Test::BritishTest)

src/Magnum/Test/CMakeLists.txt

@@ -29,6 +29,13 @@ set(CMAKE_FOLDER "Magnum/Test")
 
 find_package(Corrade REQUIRED PluginManager)
 
+corrade_add_test(BritishTest BritishTest.cpp LIBRARIES Magnum)
+# Just to have the GL headers pulled in correctly. Shouldn't be needed in most
+# cases as the headers are self-contained in MagnumExternal, but some platforms
+# such as iOS may disagree.
+if(MAGNUM_TARGET_GL)
+    target_link_libraries(BritishTest PRIVATE MagnumGL)
+endif()
 corrade_add_test(ConverterUtilitiesTest ConverterUtilitiesTest.cpp LIBRARIES Magnum Corrade::PluginManager)
 corrade_add_test(FileCallbackTest FileCallbackTest.cpp LIBRARIES Magnum)
 corrade_add_test(ImageTest ImageTest.cpp LIBRARIES MagnumTestLib)