Shaders: NO, these are not layers.

src/Magnum/Shaders/AbstractVector.cpp

@@ -31,7 +31,7 @@
 namespace Magnum { namespace Shaders {
 
 template<UnsignedInt dimensions> AbstractVector<dimensions>& AbstractVector<dimensions>::bindVectorTexture(GL::Texture2D& texture) {
-    texture.bind(VectorTextureLayer);
+    texture.bind(VectorTextureUnit);
     return *this;
 }
 

src/Magnum/Shaders/AbstractVector.h

@@ -98,9 +98,9 @@ template<UnsignedInt dimensions> class AbstractVector: public GL::AbstractShader
     #endif
         /* Those textures are quite specific (and likely reused multiple times
            per frame for e.g. text rendering, so put them in a specific slot.
-           Older iOS (and iOS WebGL) has only 8 texture binding slots, so can't
-           go above that. Binding 7 is used by TextureTools::DistanceField. */
-        enum: Int { VectorTextureLayer = 6 };
+           Older iOS (and iOS WebGL) has only 8 texture units, so can't go
+           above that. Unit 7 is used by TextureTools::DistanceField. */
+        enum: Int { VectorTextureUnit = 6 };
 
         explicit AbstractVector(NoCreateT) noexcept: GL::AbstractShaderProgram{NoCreate} {}
         explicit AbstractVector() = default;

src/Magnum/Shaders/DistanceFieldVector.cpp

@@ -99,7 +99,7 @@ template<UnsignedInt dimensions> DistanceFieldVector<dimensions>::DistanceFieldV
     #endif
     {
         GL::AbstractShaderProgram::setUniform(GL::AbstractShaderProgram::uniformLocation("vectorTexture"),
-            AbstractVector<dimensions>::VectorTextureLayer);
+            AbstractVector<dimensions>::VectorTextureUnit);
     }
 
     /* Set defaults in OpenGL ES (for desktop they are set in shader code itself) */

src/Magnum/Shaders/Flat.cpp

@@ -42,7 +42,7 @@
 namespace Magnum { namespace Shaders {
 
 namespace {
-    enum: Int { TextureLayer = 0 };
+    enum: Int { TextureUnit = 0 };
 }
 
 template<UnsignedInt dimensions> Flat<dimensions>::Flat(const Flags flags): _flags(flags) {
@@ -125,7 +125,7 @@ template<UnsignedInt dimensions> Flat<dimensions>::Flat(const Flags flags): _fla
     if(!GL::Context::current().isExtensionSupported<GL::Extensions::ARB::shading_language_420pack>(version))
     #endif
     {
-        if(flags & Flag::Textured) setUniform(uniformLocation("textureData"), TextureLayer);
+        if(flags & Flag::Textured) setUniform(uniformLocation("textureData"), TextureUnit);
     }
 
     /* Set defaults in OpenGL ES (for desktop they are set in shader code itself) */
@@ -158,7 +158,7 @@ template<UnsignedInt dimensions> Flat<dimensions>& Flat<dimensions>::setColor(co
 template<UnsignedInt dimensions> Flat<dimensions>& Flat<dimensions>::bindTexture(GL::Texture2D& texture) {
     CORRADE_ASSERT(_flags & Flag::Textured,
         "Shaders::Flat::bindTexture(): the shader was not created with texturing enabled", *this);
-    texture.bind(TextureLayer);
+    texture.bind(TextureUnit);
     return *this;
 }
 

src/Magnum/Shaders/Phong.cpp

@@ -47,10 +47,10 @@ namespace Magnum { namespace Shaders {
 
 namespace {
     enum: Int {
-        AmbientTextureLayer = 0,
-        DiffuseTextureLayer = 1,
-        SpecularTextureLayer = 2,
-        NormalTextureLayer = 3
+        AmbientTextureUnit = 0,
+        DiffuseTextureUnit = 1,
+        SpecularTextureUnit = 2,
+        NormalTextureUnit = 3
     };
 }
 
@@ -179,11 +179,11 @@ Phong::Phong(const Flags flags, const UnsignedInt lightCount): _flags{flags}, _l
     if(flags && !GL::Context::current().isExtensionSupported<GL::Extensions::ARB::shading_language_420pack>(version))
     #endif
     {
-        if(flags & Flag::AmbientTexture) setUniform(uniformLocation("ambientTexture"), AmbientTextureLayer);
+        if(flags & Flag::AmbientTexture) setUniform(uniformLocation("ambientTexture"), AmbientTextureUnit);
         if(lightCount) {
-            if(flags & Flag::DiffuseTexture) setUniform(uniformLocation("diffuseTexture"), DiffuseTextureLayer);
-            if(flags & Flag::SpecularTexture) setUniform(uniformLocation("specularTexture"), SpecularTextureLayer);
-            if(flags & Flag::NormalTexture) setUniform(uniformLocation("normalTexture"), NormalTextureLayer);
+            if(flags & Flag::DiffuseTexture) setUniform(uniformLocation("diffuseTexture"), DiffuseTextureUnit);
+            if(flags & Flag::SpecularTexture) setUniform(uniformLocation("specularTexture"), SpecularTextureUnit);
+            if(flags & Flag::NormalTexture) setUniform(uniformLocation("normalTexture"), NormalTextureUnit);
         }
     }
 
@@ -216,7 +216,7 @@ Phong& Phong::setAmbientColor(const Magnum::Color4& color) {
 Phong& Phong::bindAmbientTexture(GL::Texture2D& texture) {
     CORRADE_ASSERT(_flags & Flag::AmbientTexture,
         "Shaders::Phong::bindAmbientTexture(): the shader was not created with ambient texture enabled", *this);
-    texture.bind(AmbientTextureLayer);
+    texture.bind(AmbientTextureUnit);
     return *this;
 }
 
@@ -228,7 +228,7 @@ Phong& Phong::setDiffuseColor(const Magnum::Color4& color) {
 Phong& Phong::bindDiffuseTexture(GL::Texture2D& texture) {
     CORRADE_ASSERT(_flags & Flag::DiffuseTexture,
         "Shaders::Phong::bindDiffuseTexture(): the shader was not created with diffuse texture enabled", *this);
-    if(_lightCount) texture.bind(DiffuseTextureLayer);
+    if(_lightCount) texture.bind(DiffuseTextureUnit);
     return *this;
 }
 
@@ -240,21 +240,21 @@ Phong& Phong::setSpecularColor(const Magnum::Color4& color) {
 Phong& Phong::bindSpecularTexture(GL::Texture2D& texture) {
     CORRADE_ASSERT(_flags & Flag::SpecularTexture,
         "Shaders::Phong::bindSpecularTexture(): the shader was not created with specular texture enabled", *this);
-    if(_lightCount) texture.bind(SpecularTextureLayer);
+    if(_lightCount) texture.bind(SpecularTextureUnit);
     return *this;
 }
 
 Phong& Phong::bindNormalTexture(GL::Texture2D& texture) {
     CORRADE_ASSERT(_flags & Flag::NormalTexture,
         "Shaders::Phong::bindNormalTexture(): the shader was not created with normal texture enabled", *this);
-    if(_lightCount) texture.bind(NormalTextureLayer);
+    if(_lightCount) texture.bind(NormalTextureUnit);
     return *this;
 }
 
 Phong& Phong::bindTextures(GL::Texture2D* ambient, GL::Texture2D* diffuse, GL::Texture2D* specular, GL::Texture2D* normal) {
     CORRADE_ASSERT(_flags & (Flag::AmbientTexture|Flag::DiffuseTexture|Flag::SpecularTexture|Flag::NormalTexture),
         "Shaders::Phong::bindTextures(): the shader was not created with any textures enabled", *this);
-    GL::AbstractTexture::bind(AmbientTextureLayer, {ambient, diffuse, specular, normal});
+    GL::AbstractTexture::bind(AmbientTextureUnit, {ambient, diffuse, specular, normal});
     return *this;
 }
 

src/Magnum/Shaders/Vector.cpp

@@ -96,7 +96,7 @@ template<UnsignedInt dimensions> Vector<dimensions>::Vector(const Flags flags):
     if(!GL::Context::current().isExtensionSupported<GL::Extensions::ARB::shading_language_420pack>(version))
     #endif
     {
-        GL::AbstractShaderProgram::setUniform(GL::AbstractShaderProgram::uniformLocation("vectorTexture"), AbstractVector<dimensions>::VectorTextureLayer);
+        GL::AbstractShaderProgram::setUniform(GL::AbstractShaderProgram::uniformLocation("vectorTexture"), AbstractVector<dimensions>::VectorTextureUnit);
     }
 
     /* Set defaults in OpenGL ES (for desktop they are set in shader code itself) */