doc: expose more texture-related GL defines as search keywords.

src/Magnum/BufferTexture.h

@@ -83,6 +83,7 @@ and respective function documentation for more information.
 
 @see @ref Texture, @ref TextureArray, @ref CubeMapTexture,
     @ref CubeMapTextureArray, @ref RectangleTexture, @ref MultisampleTexture
+@m_keywords{GL_TEXTURE_BUFFER}
 @requires_gl31 Extension @extension{ARB,texture_buffer_object}
 @requires_gles30 Not defined in OpenGL ES 2.0.
 @requires_gles32 Extension @extension{ANDROID,extension_pack_es31a} /

src/Magnum/CubeMapTexture.h

@@ -39,6 +39,7 @@ namespace Magnum {
 @brief Cube map coordinate
 
 @see @ref CubeMapTexture
+@m_enum_values_as_keywords
 */
 enum class CubeMapCoordinate: GLenum {
     PositiveX = GL_TEXTURE_CUBE_MAP_POSITIVE_X,     /**< +X cube side */
@@ -93,6 +94,7 @@ of the cube, which intersects one of the six sides of the cube map. See
 @see @ref Renderer::Feature::SeamlessCubeMapTexture, @ref CubeMapTextureArray,
     @ref Texture, @ref TextureArray, @ref RectangleTexture, @ref BufferTexture,
     @ref MultisampleTexture
+@m_keywords{GL_TEXTURE_CUBE_MAP}
 */
 class MAGNUM_EXPORT CubeMapTexture: public AbstractTexture {
     friend Implementation::TextureState;

src/Magnum/CubeMapTextureArray.h

@@ -81,6 +81,7 @@ more information about usage in shaders.
 @see @ref Renderer::Feature::SeamlessCubeMapTexture, @ref CubeMapTexture,
     @ref Texture, @ref TextureArray, @ref RectangleTexture, @ref BufferTexture,
     @ref MultisampleTexture
+@m_keywords{GL_TEXTURE_CUBE_MAP_ARRAY}
 @requires_gl40 Extension @extension{ARB,texture_cube_map_array}
 @requires_gles30 Not defined in OpenGL ES 2.0.
 @requires_gles32 Extension @extension{ANDROID,extension_pack_es31a} /

src/Magnum/MultisampleTexture.h

@@ -92,6 +92,7 @@ Note that multisample textures don't support compressed formats.
 @see @ref MultisampleTexture2D, @ref MultisampleTexture2DArray, @ref Texture,
     @ref TextureArray, @ref CubeMapTexture, @ref CubeMapTextureArray,
     @ref RectangleTexture, @ref BufferTexture
+@m_keywords{GL_TEXTURE_2D_MULTISAMPLE GL_TEXTURE_2D_MULTISAMPLE_ARRAY}
 @requires_gl32 Extension @extension{ARB,texture_multisample}
 @requires_gles31 Multisample 2D textures are not available in OpenGL ES 3.0 and
     older.

src/Magnum/RectangleTexture.h

@@ -67,6 +67,7 @@ in shaders.
 
 @see @ref Texture, @ref TextureArray, @ref CubeMapTexture,
     @ref CubeMapTextureArray, @ref BufferTexture, @ref MultisampleTexture
+@m_keywords{GL_TEXTURE_RECTANGLE}
 @requires_gl31 Extension @extension{ARB,texture_rectangle}
 @requires_gl Rectangle textures are not available in OpenGL ES and WebGL.
  */

src/Magnum/Texture.h

@@ -98,6 +98,7 @@ information about usage in shaders.
 @see @ref Texture1D, @ref Texture2D, @ref Texture3D, @ref TextureArray,
     @ref CubeMapTexture, @ref CubeMapTextureArray, @ref RectangleTexture,
     @ref BufferTexture, @ref MultisampleTexture
+@m_keywords{GL_TEXTURE_1D GL_TEXTURE_2D GL_TEXTURE_3D}
 @requires_gles30 Extension @extension{OES,texture_3D} for 3D textures in
     OpenGL ES 2.0.
 @requires_webgl20 3D textures are not available in WebGL 1.0.

src/Magnum/TextureArray.h

@@ -90,6 +90,7 @@ in shaders.
 @see @ref Texture1DArray, @ref Texture2DArray, @ref Texture,
     @ref CubeMapTexture, @ref CubeMapTextureArray, @ref RectangleTexture,
     @ref BufferTexture, @ref MultisampleTexture
+@m_keywords{GL_TEXTURE_1D_ARRAY GL_TEXTURE_2D_ARRAY}
 @requires_gl30 Extension @extension{EXT,texture_array}
 @requires_gles30 Array textures are not available in OpenGL ES 2.0.
 @requires_webgl20 Array textures are not available in WebGL 1.0.