Allocation-free overloads for *::setLabel().

In most cases the label is set directly from code, e.g.:

    texture.setLabel("diffuse-duck");

Avoiding conversion to std::string and passing char(&)[size] directly
will avoid one allocation and deallocation. Better solution would be to
use std::string_view everywhere, but we're not in C++17 yet.

src/Magnum/AbstractObject.cpp

@@ -26,6 +26,7 @@
 #include "AbstractObject.h"
 
 #include <Corrade/Utility/Assert.h>
+#include <Corrade/Containers/Array.h>
 
 #include "Magnum/Context.h"
 #include "Magnum/Extensions.h"
@@ -123,26 +124,26 @@ Int AbstractObject::maxLabelLength() {
     return value;
 }
 
-void AbstractObject::labelImplementationNoOp(GLenum, GLuint, const std::string&) {}
+void AbstractObject::labelImplementationNoOp(GLenum, GLuint, Containers::ArrayReference<const char>) {}
 
-void AbstractObject::labelImplementationKhr(const GLenum identifier, const GLuint name, const std::string& label) {
+void AbstractObject::labelImplementationKhr(const GLenum identifier, const GLuint name, const Containers::ArrayReference<const char> label) {
     /** @todo Re-enable when extension loader is available for ES */
     #ifndef MAGNUM_TARGET_GLES
-    glObjectLabel(identifier, name, label.size(), label.data());
+    glObjectLabel(identifier, name, label.size(), label);
     #else
     static_cast<void>(identifier);
     static_cast<void>(name);
     static_cast<void>(label);
     CORRADE_INTERNAL_ASSERT(false);
-    //glObjectLabelKHR(identifier, name, label.size(), label.data());
+    //glObjectLabelKHR(identifier, name, label.size(), label);
     #endif
 }
 
-void AbstractObject::labelImplementationExt(const GLenum identifier, const GLuint name, const std::string& label) {
+void AbstractObject::labelImplementationExt(const GLenum identifier, const GLuint name, const Containers::ArrayReference<const char> label) {
     const GLenum type = extTypeFromKhrIdentifier(identifier);
     /** @todo Re-enable when extension loader is available for ES */
     #ifndef MAGNUM_TARGET_GLES
-    glLabelObjectEXT(type, name, label.size(), label.data());
+    glLabelObjectEXT(type, name, label.size(), label);
     #else
     static_cast<void>(type);
     static_cast<void>(name);

src/Magnum/AbstractObject.h

@@ -30,9 +30,10 @@
  */
 
 #include <string>
+#include <Corrade/Containers/Containers.h>
 
+#include "Magnum/Magnum.h"
 #include "Magnum/OpenGL.h"
-#include "Magnum/Types.h"
 #include "Magnum/visibility.h"
 
 namespace Magnum {
@@ -66,9 +67,9 @@ class MAGNUM_EXPORT AbstractObject {
         MAGNUM_LOCAL ~AbstractObject() = default;
 
     private:
-        static MAGNUM_LOCAL void labelImplementationNoOp(GLenum, GLuint, const std::string&);
-        static MAGNUM_LOCAL void labelImplementationExt(GLenum identifier, GLuint name, const std::string& label);
-        static MAGNUM_LOCAL void labelImplementationKhr(GLenum identifier, GLuint name, const std::string& label);
+        static MAGNUM_LOCAL void labelImplementationNoOp(GLenum, GLuint, Containers::ArrayReference<const char> label);
+        static MAGNUM_LOCAL void labelImplementationExt(GLenum identifier, GLuint name, Containers::ArrayReference<const char> label);
+        static MAGNUM_LOCAL void labelImplementationKhr(GLenum identifier, GLuint name, Containers::ArrayReference<const char> label);
         static MAGNUM_LOCAL std::string getLabelImplementationNoOp(GLenum, GLuint);
         static MAGNUM_LOCAL std::string getLabelImplementationExt(GLenum identifier, GLuint name);
         static MAGNUM_LOCAL std::string getLabelImplementationKhr(GLenum identifier, GLuint name);

src/Magnum/AbstractShaderProgram.cpp

@@ -225,7 +225,7 @@ std::string AbstractShaderProgram::label() const {
     #endif
 }
 
-AbstractShaderProgram& AbstractShaderProgram::setLabel(const std::string& label) {
+AbstractShaderProgram& AbstractShaderProgram::setLabelInternal(const Containers::ArrayReference<const char> label) {
     #ifndef MAGNUM_TARGET_GLES
     Context::current()->state().debug->labelImplementation(GL_PROGRAM, _id, label);
     #else

src/Magnum/AbstractShaderProgram.h

@@ -31,6 +31,7 @@
 
 #include <functional>
 #include <string>
+#include <Corrade/Containers/Array.h>
 #include <Corrade/Containers/EnumSet.h>
 
 #include "Magnum/AbstractObject.h"
@@ -540,7 +541,14 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
          *      @def_gl{PROGRAM} or @fn_gl_extension2{LabelObject,EXT,debug_label}
          *      with @def_gl{PROGRAM_OBJECT_EXT}
          */
-        AbstractShaderProgram& setLabel(const std::string& label);
+        AbstractShaderProgram& setLabel(const std::string& label) {
+            return setLabelInternal({label.data(), label.size()});
+        }
+
+        /** @overload */
+        template<std::size_t size> AbstractShaderProgram& setLabel(const char (&label)[size]) {
+            return setLabelInternal(label);
+        }
 
         /**
          * @brief Validate program
@@ -817,6 +825,8 @@ class MAGNUM_EXPORT AbstractShaderProgram: public AbstractObject {
         #endif
 
     private:
+        AbstractShaderProgram& setLabelInternal(Containers::ArrayReference<const char> label);
+
         #ifndef MAGNUM_BUILD_DEPRECATED
         void use();
         #endif

src/Magnum/AbstractTexture.cpp

@@ -189,7 +189,7 @@ std::string AbstractTexture::label() const {
     return Context::current()->state().debug->getLabelImplementation(GL_TEXTURE, _id);
 }
 
-AbstractTexture& AbstractTexture::setLabel(const std::string& label) {
+AbstractTexture& AbstractTexture::setLabelInternal(const Containers::ArrayReference<const char> label) {
     Context::current()->state().debug->labelImplementation(GL_TEXTURE, _id, label);
     return *this;
 }

src/Magnum/AbstractTexture.h

@@ -29,6 +29,8 @@
  * @brief Class @ref Magnum::AbstractTexture
  */
 
+#include <Corrade/Containers/Array.h>
+
 #include "Magnum/Sampler.h"
 #include "Magnum/AbstractObject.h"
 
@@ -258,7 +260,14 @@ class MAGNUM_EXPORT AbstractTexture: public AbstractObject {
          *      @fn_gl_extension2{LabelObject,EXT,debug_label} with
          *      @def_gl{TEXTURE}
          */
-        AbstractTexture& setLabel(const std::string& label);
+        AbstractTexture& setLabel(const std::string& label) {
+            return setLabelInternal({label.data(), label.size()});
+        }
+
+        /** @overload */
+        template<std::size_t size> AbstractTexture& setLabel(const char(&label)[size]) {
+            return setLabelInternal(label);
+        }
 
         /** @brief OpenGL texture ID */
         GLuint id() const { return _id; }
@@ -288,6 +297,8 @@ class MAGNUM_EXPORT AbstractTexture: public AbstractObject {
 
         explicit AbstractTexture(GLenum target);
 
+        AbstractTexture& setLabelInternal(Containers::ArrayReference<const char> label);
+
         /* Unlike bind() this also sets the texture binding unit as active */
         void MAGNUM_LOCAL bindInternal();
 

src/Magnum/Buffer.cpp

@@ -138,7 +138,7 @@ std::string Buffer::label() const {
     #endif
 }
 
-Buffer& Buffer::setLabel(const std::string& label) {
+Buffer& Buffer::setLabelInternal(const Containers::ArrayReference<const char> label) {
     #ifndef MAGNUM_TARGET_GLES
     Context::current()->state().debug->labelImplementation(GL_BUFFER, _id, label);
     #else

src/Magnum/Buffer.h

@@ -582,7 +582,14 @@ class MAGNUM_EXPORT Buffer: public AbstractObject {
          *      or @fn_gl_extension2{LabelObject,EXT,debug_label} with
          *      @def_gl{BUFFER_OBJECT_EXT}
          */
-        Buffer& setLabel(const std::string& label);
+        Buffer& setLabel(const std::string& label) {
+            return setLabelInternal({label.data(), label.size()});
+        }
+
+        /** @overload */
+        template<std::size_t size> Buffer& setLabel(const char(&label)[size]) {
+            return setLabelInternal(label);
+        }
 
         /** @brief Target hint */
         Target targetHint() const { return _targetHint; }
@@ -854,6 +861,8 @@ class MAGNUM_EXPORT Buffer: public AbstractObject {
         #endif
 
     private:
+        Buffer& setLabelInternal(Containers::ArrayReference<const char> label);
+
         static void bind(Target hint, GLuint id);
         Target MAGNUM_LOCAL bindInternal(Target hint);
 

src/Magnum/BufferTexture.h

@@ -269,6 +269,10 @@ class MAGNUM_EXPORT BufferTexture: public AbstractTexture {
             AbstractTexture::setLabel(label);
             return *this;
         }
+        template<std::size_t size> BufferTexture& setLabel(const char(&label)[size]) {
+            AbstractTexture::setLabel<size>(label);
+            return *this;
+        }
         #endif
 
     private:

src/Magnum/CubeMapTexture.h

@@ -382,6 +382,10 @@ class MAGNUM_EXPORT CubeMapTexture: public AbstractTexture {
             AbstractTexture::setLabel(label);
             return *this;
         }
+        template<std::size_t size> CubeMapTexture& setLabel(const char(&label)[size]) {
+            AbstractTexture::setLabel<size>(label);
+            return *this;
+        }
         #endif
 };
 

src/Magnum/CubeMapTextureArray.h

@@ -405,6 +405,10 @@ class CubeMapTextureArray: public AbstractTexture {
             AbstractTexture::setLabel(label);
             return *this;
         }
+        template<std::size_t size> CubeMapTextureArray& setLabel(const char(&label)[size]) {
+            AbstractTexture::setLabel<size>(label);
+            return *this;
+        }
         #endif
 };
 

src/Magnum/Framebuffer.cpp

@@ -112,7 +112,7 @@ std::string Framebuffer::label() const {
     return Context::current()->state().debug->getLabelImplementation(GL_FRAMEBUFFER, _id);
 }
 
-Framebuffer& Framebuffer::setLabel(const std::string& label) {
+Framebuffer& Framebuffer::setLabelInternal(const Containers::ArrayReference<const char> label) {
     Context::current()->state().debug->labelImplementation(GL_FRAMEBUFFER, _id, label);
     return *this;
 }

src/Magnum/Framebuffer.h

@@ -354,7 +354,14 @@ class MAGNUM_EXPORT Framebuffer: public AbstractFramebuffer, public AbstractObje
          *      @fn_gl_extension2{LabelObject,EXT,debug_label} with
          *      @def_gl{FRAMEBUFFER}
          */
-        Framebuffer& setLabel(const std::string& label);
+        Framebuffer& setLabel(const std::string& label) {
+            return setLabelInternal({label.data(), label.size()});
+        }
+
+        /** @overload */
+        template<std::size_t size> Framebuffer& setLabel(const char(&label)[size]) {
+            return setLabelInternal(label);
+        }
 
         /**
          * @brief Check framebuffer status
@@ -627,6 +634,8 @@ class MAGNUM_EXPORT Framebuffer: public AbstractFramebuffer, public AbstractObje
         #endif
 
     private:
+        Framebuffer& setLabelInternal(Containers::ArrayReference<const char> label);
+
         void MAGNUM_LOCAL renderbufferImplementationDefault(BufferAttachment attachment, Renderbuffer& renderbuffer);
         #ifndef MAGNUM_TARGET_GLES
         void MAGNUM_LOCAL renderbufferImplementationDSA(BufferAttachment attachment, Renderbuffer& renderbuffer);

src/Magnum/Implementation/DebugState.h

@@ -36,7 +36,7 @@ struct DebugState {
     explicit DebugState(Context& context, std::vector<std::string>& extensions);
 
     std::string(*getLabelImplementation)(GLenum, GLuint);
-    void(*labelImplementation)(GLenum, GLuint, const std::string&);
+    void(*labelImplementation)(GLenum, GLuint, Containers::ArrayReference<const char>);
 
     void(*messageInsertImplementation)(DebugMessage::Source, DebugMessage::Type, UnsignedInt, DebugMessage::Severity, const std::string&);
     void(*messageCallbackImplementation)(DebugMessage::Callback, const void*);

src/Magnum/Mesh.cpp

@@ -148,7 +148,7 @@ std::string Mesh::label() const {
     #endif
 }
 
-Mesh& Mesh::setLabel(const std::string& label) {
+Mesh& Mesh::setLabelInternal(const Containers::ArrayReference<const char> label) {
     #ifndef MAGNUM_TARGET_GLES
     Context::current()->state().debug->labelImplementation(GL_VERTEX_ARRAY, _id, label);
     #else

src/Magnum/Mesh.h

@@ -467,7 +467,14 @@ class MAGNUM_EXPORT Mesh: public AbstractObject {
          *      @def_gl{VERTEX_ARRAY} or @fn_gl_extension2{LabelObject,EXT,debug_label}
          *      with @def_gl{VERTEX_ARRAY_OBJECT_EXT}
          */
-        Mesh& setLabel(const std::string& label);
+        Mesh& setLabel(const std::string& label) {
+            return setLabelInternal({label.data(), label.size()});
+        }
+
+        /** @overload */
+        template<std::size_t size> Mesh& setLabelInternal(const char(&label)[size]) {
+            return setLabelInternal(label);
+        }
 
         /**
          * @brief Whether the mesh is indexed
@@ -836,6 +843,8 @@ class MAGNUM_EXPORT Mesh: public AbstractObject {
         #endif
         #endif
 
+        Mesh& setLabelInternal(Containers::ArrayReference<const char> label);
+
         /* Computing stride of interleaved vertex attributes */
         template<UnsignedInt location, class T, class ...U> static GLsizei strideOfInterleaved(const AbstractShaderProgram::Attribute<location, T>& attribute, const U&... attributes) {
             return attribute.vectorSize()*AbstractShaderProgram::Attribute<location, T>::VectorCount + strideOfInterleaved(attributes...);

src/Magnum/MultisampleTexture.h

@@ -180,6 +180,10 @@ template<UnsignedInt dimensions> class MultisampleTexture: public AbstractTextur
             AbstractTexture::setLabel(label);
             return *this;
         }
+        template<std::size_t size> MultisampleTexture<dimensions>& setLabel(const char(&label)[size]) {
+            AbstractTexture::setLabel<size>(label);
+            return *this;
+        }
         #endif
 };
 

src/Magnum/Query.cpp

@@ -66,7 +66,7 @@ std::string AbstractQuery::label() const {
     #endif
 }
 
-AbstractQuery& AbstractQuery::setLabel(const std::string& label) {
+AbstractQuery& AbstractQuery::setLabelInternal(const Containers::ArrayReference<const char> label) {
     #ifndef MAGNUM_TARGET_GLES
     Context::current()->state().debug->labelImplementation(GL_QUERY, _id, label);
     #else

src/Magnum/Query.h

@@ -29,6 +29,7 @@
  * @brief Class @ref Magnum::AbstractQuery, @ref Magnum::PrimitiveQuery, @ref Magnum::SampleQuery, @ref Magnum::TimeQuery
  */
 
+#include <Corrade/Containers/Array.h>
 #include <Corrade/Utility/Assert.h>
 
 #include "Magnum/AbstractObject.h"
@@ -84,7 +85,14 @@ class MAGNUM_EXPORT AbstractQuery: public AbstractObject {
          *      @def_gl{QUERY} or @fn_gl_extension2{LabelObject,EXT,debug_label}
          *      with @def_gl{QUERY_OBJECT_EXT}
          */
-        AbstractQuery& setLabel(const std::string& label);
+        AbstractQuery& setLabel(const std::string& label) {
+            return setLabelInternal({label.data(), label.size()});
+        }
+
+        /** @overload */
+        template<std::size_t size> AbstractQuery& setLabel(const char(&label)[size]) {
+            return setLabelInternal(label);
+        }
 
         /**
          * @brief Whether the result is available
@@ -140,6 +148,8 @@ class MAGNUM_EXPORT AbstractQuery: public AbstractObject {
         void begin(GLenum target);
 
     private:
+        AbstractQuery& setLabelInternal(Containers::ArrayReference<const char> label);
+
         GLuint _id;
         GLenum target;
 };
@@ -217,6 +227,10 @@ class PrimitiveQuery: public AbstractQuery {
             AbstractQuery::setLabel(label);
             return *this;
         }
+        template<std::size_t size> PrimitiveQuery& setLabel(const char(&label)[size]) {
+            AbstractQuery::setLabel<size>(label);
+            return *this;
+        }
         #endif
 };
 #endif
@@ -367,6 +381,10 @@ class SampleQuery: public AbstractQuery {
             AbstractQuery::setLabel(label);
             return *this;
         }
+        template<std::size_t size> SampleQuery& setLabel(const char(&label)[size]) {
+            AbstractQuery::setLabel<size>(label);
+            return *this;
+        }
         #endif
 };
 
@@ -446,6 +464,10 @@ class TimeQuery: public AbstractQuery {
             AbstractQuery::setLabel(label);
             return *this;
         }
+        template<std::size_t size> TimeQuery& setLabel(const char(&label)[size]) {
+            AbstractQuery::setLabel<size>(label);
+            return *this;
+        }
         #endif
 };
 

src/Magnum/RectangleTexture.h

@@ -404,6 +404,10 @@ class MAGNUM_EXPORT RectangleTexture: public AbstractTexture {
             AbstractTexture::setLabel(label);
             return *this;
         }
+        template<std::size_t size> RectangleTexture& setLabel(const char(&label)[size]) {
+            AbstractTexture::setLabel<size>(label);
+            return *this;
+        }
         #endif
 };
 

src/Magnum/Renderbuffer.cpp

@@ -81,7 +81,7 @@ std::string Renderbuffer::label() const {
     return Context::current()->state().debug->getLabelImplementation(GL_RENDERBUFFER, _id);
 }
 
-Renderbuffer& Renderbuffer::setLabel(const std::string& label) {
+Renderbuffer& Renderbuffer::setLabelInternal(const Containers::ArrayReference<const char> label) {
     Context::current()->state().debug->labelImplementation(GL_RENDERBUFFER, _id, label);
     return *this;
 }

src/Magnum/Renderbuffer.h

@@ -29,6 +29,8 @@
  * @brief Class @ref Magnum::Renderbuffer
  */
 
+#include <Corrade/Containers/Array.h>
+
 #include "Magnum/AbstractObject.h"
 #include "Magnum/Magnum.h"
 
@@ -135,7 +137,14 @@ class MAGNUM_EXPORT Renderbuffer: public AbstractObject {
          *      @fn_gl_extension2{LabelObject,EXT,debug_label} with
          *      @def_gl{RENDERBUFFER}
          */
-        Renderbuffer& setLabel(const std::string& label);
+        Renderbuffer& setLabel(const std::string& label) {
+            return setLabelInternal({label.data(), label.size()});
+        }
+
+        /** @overload */
+        template<std::size_t size> Renderbuffer& setLabel(const char(&label)[size]) {
+            return setLabelInternal(label);
+        }
 
         /**
          * @brief Set renderbuffer storage
@@ -169,6 +178,8 @@ class MAGNUM_EXPORT Renderbuffer: public AbstractObject {
         void setStorageMultisample(Int samples, RenderbufferFormat internalFormat, const Vector2i& size);
 
     private:
+        Renderbuffer& setLabelInternal(Containers::ArrayReference<const char> label);
+
         void MAGNUM_LOCAL storageImplementationDefault(RenderbufferFormat internalFormat, const Vector2i& size);
         #ifndef MAGNUM_TARGET_GLES
         void MAGNUM_LOCAL storageImplementationDSA(RenderbufferFormat internalFormat, const Vector2i& size);

src/Magnum/Shader.cpp

@@ -580,7 +580,7 @@ std::string Shader::label() const {
     #endif
 }
 
-Shader& Shader::setLabel(const std::string& label) {
+Shader& Shader::setLabelInternal(const Containers::ArrayReference<const char> label) {
     #ifndef MAGNUM_TARGET_GLES
     Context::current()->state().debug->labelImplementation(GL_SHADER, _id, label);
     #else

src/Magnum/Shader.h

@@ -32,6 +32,7 @@
 #include <functional>
 #include <string>
 #include <vector>
+#include <Corrade/Containers/Array.h>
 
 #include "Magnum/AbstractObject.h"
 #include "Magnum/Magnum.h"
@@ -504,7 +505,14 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
          *      @def_gl{SHADER} or @fn_gl_extension2{LabelObject,EXT,debug_label}
          *      with @def_gl{SHADER_OBJECT_EXT}
          */
-        Shader& setLabel(const std::string& label);
+        Shader& setLabel(const std::string& label) {
+            return setLabelInternal({label.data(), label.size()});
+        }
+
+        /** @overload */
+        template<std::size_t size> Shader& setLabel(const char(&label)[size]) {
+            return setLabelInternal(label);
+        }
 
         /** @brief %Shader type */
         Type type() const { return _type; }
@@ -545,6 +553,8 @@ class MAGNUM_EXPORT Shader: public AbstractObject {
         bool compile() { return compile({*this}); }
 
     private:
+        Shader& setLabelInternal(Containers::ArrayReference<const char> label);
+
         Type _type;
         GLuint _id;
 

src/Magnum/Texture.h

@@ -759,6 +759,10 @@ template<UnsignedInt dimensions> class Texture: public AbstractTexture {
             AbstractTexture::setLabel(label);
             return *this;
         }
+        template<std::size_t size> Texture<dimensions>& setLabel(const char(&label)[size]) {
+            AbstractTexture::setLabel<size>(label);
+            return *this;
+        }
         #endif
 };
 

src/Magnum/TextureArray.h

@@ -389,6 +389,10 @@ template<UnsignedInt dimensions> class TextureArray: public AbstractTexture {
             AbstractTexture::setLabel(label);
             return *this;
         }
+        template<std::size_t size> TextureArray<dimensions>& setLabel(const char(&label)[size]) {
+            AbstractTexture::setLabel<size>(label);
+            return *this;
+        }
         #endif
 };