Use functions to bind textures to shader rather than *Texture::bind().

Why did I do this:

 * It is more clean, shorter and nice looking with method chaining,
   i.e. instead of:

    shader.setColor(...)
          .setOtherParam(5);
    texture1.bind(MyShader::Texture1Layer);
    texture2.bind(MyShader::Texture2Layer);

   We now have this:

    shader.setColor(...)
          .setOtherParam(5)
          .setTexture1(texture1)
          .setTexture2(texture2);

 * It is now also clear which texture type is expected, the layer
   constant did not say anything about type.
 * Also it is possible to use new features (multi bind, bindless
   textures etc.) while preserving the same public API.

The only potential disadvantage is that the textures don't stay bound
like uniform values do, but this become a non-issue with bindless
textures. As usual, the old way is now deprecated and will be removed in
some future release.

src/Magnum/AbstractShaderProgram.h

@@ -63,14 +63,6 @@ enum: UnsignedInt {
     NormalOutput = 1
 };
 @endcode
--   **Layers for texture uniforms** to which the textures will be bound before
-    rendering, for example:
-@code
-enum: Int {
-    DiffuseTextureLayer = 0,
-    SpecularTextureLayer = 1
-};
-@endcode
 -   **Uniform locations** for setting uniform data (see below) (private
     variables), for example:
 @code
@@ -111,6 +103,18 @@ MyShader& setProjection(const Matrix4& matrix) {
     return *this;
 }
 @endcode
+-   **Texture setting functions** in which you bind the textures to particular
+    layers using @ref AbstractTexture::bind() and equivalent, for example:
+@code
+MyShader& setDiffuseTexture(Texture2D& texture) {
+    texture->bind(0);
+    return *this;
+}
+MyShader& setSpecularTexture(Texture2D& texture) {
+    texture->bind(1);
+    return *this;
+}
+@endcode
 
 @subsection AbstractShaderProgram-attribute-location Binding attribute location
 
@@ -230,8 +234,8 @@ uniform sampler2D diffuseTexture;
 uniform sampler2D specularTexture;
 @endcode
 @code
-setUniform(DiffuseTextureUniform, DiffuseTextureLayer);
+setUniform(DiffuseTextureUniform, 0);
-setUniform(SpecularTextureUniform, SpecularTextureLayer);
+setUniform(SpecularTextureUniform, 1);
 @endcode
 
 @see @ref Shader::maxTextureImageUnits()
@@ -248,15 +252,13 @@ Basic workflow with %AbstractShaderProgram subclasses is: instance shader
 class, configure attribute binding in meshes (see @ref Mesh-configuration "Mesh documentation"
 for more information) and map shader outputs to framebuffer attachments if
 needed (see @ref Framebuffer-usage "Framebuffer documentation" for more
-information). In each draw event set uniforms, bind specific framebuffer (if
+information). In each draw event set all required shader parameters, bind
-needed) and bind required textures to their respective layers using
+specific framebuffer (if needed) and then call @ref Mesh::draw(). Example:
-@ref AbstractTexture::bind(Int). Then call @ref Mesh::draw(). Example:
 @code
 shader.setTransformation(transformation)
-    .setProjection(projection);
+    .setProjection(projection)
-
+    .setDiffuseTexture(diffuseTexture)
-diffuseTexture.bind(MyShader::DiffuseTextureLayer);
+    .setSpecularTexture(specularTexture);
-specularTexture.bind(MyShader::SpecularTextureLayer);
 
 mesh.draw(shader);
 @endcode

src/Magnum/AbstractTexture.h

@@ -208,10 +208,13 @@ class MAGNUM_EXPORT AbstractTexture: public AbstractObject {
         /**
          * @brief Bind texture for rendering
          *
-         * Sets current texture as active in given layer. The layer must be
+         * Sets current texture as active in given layer. Note that only one
-         * between 0 and @ref maxLayers(). Note that only one texture can be
+         * texture can be bound to given layer. If @extension{EXT,direct_state_access}
-         * bound to given layer. If @extension{EXT,direct_state_access} is not
+         * is not available, the layer is made active before binding the
-         * available, the layer is made active before binding the texture.
+         * texture.
+         * @note This function is meant to be used only internally from
+         *      @ref AbstractShaderProgram subclasses. See its documentation
+         *      for more information.
          * @see @ref maxLayers(), @fn_gl{ActiveTexture}, @fn_gl{BindTexture} or
          *      @fn_gl_extension{BindMultiTexture,EXT,direct_state_access}
          */

src/Magnum/BufferTexture.h

@@ -181,11 +181,10 @@ constexpr static Vector3 data[] = {
 buffer.setData(data, BufferUsage::StaticDraw);
 @endcode
 
-The texture is bound to layer specified by shader via @ref bind(). In shader,
+In shader, the texture is used via `samplerBuffer`, `isamplerBuffer` or
-the texture is used via `samplerBuffer`, `isamplerBuffer` or `usamplerBuffer`.
+`usamplerBuffer`. Unlike in classic textures, coordinates for buffer textures
-Unlike in classic textures, coordinates for buffer textures are integer
+are integer coordinates passed to `texelFetch()`. See @ref AbstractShaderProgram
-coordinates passed to `texelFetch()`. See also @ref AbstractShaderProgram
+documentation for more information about usage in shaders.
-documentation for more information.
 
 @section BufferTexture-performance-optimization Performance optimizations
 

src/Magnum/CubeMapTexture.h

@@ -69,12 +69,11 @@ texture.setMagnificationFilter(Sampler::Filter::Linear)
     // ...
 @endcode
 
-The texture is bound to layer specified by shader via @ref bind(). In shader,
+In shader, the texture is used via `samplerCube`, `samplerCubeShadow`,
-the texture is used via `samplerCube`, `samplerCubeShadow`, `isamplerCube` or
+`isamplerCube` or `usamplerCube`. Unlike in classic textures, coordinates for
-`usamplerCube`. Unlike in classic textures, coordinates for cube map textures
+cube map textures is signed three-part vector from the center of the cube,
-is signed three-part vector from the center of the cube, which intersects one
+which intersects one of the six sides of the cube map. See
-of the six sides of the cube map. See also @ref AbstractShaderProgram for more
+@ref AbstractShaderProgram for more information about usage in shaders.
-information about usage in shaders.
 
 @see @ref Renderer::Feature::SeamlessCubeMapTexture, @ref CubeMapTextureArray,
     @ref Texture, @ref BufferTexture

src/Magnum/CubeMapTextureArray.h

@@ -67,12 +67,11 @@ for(std::size_t i = 0; i != 4; i += 6) {
 texture.generateMipmap();
 @endcode
 
-The texture is bound to layer specified by shader via @ref bind(). In shader,
+In shader, the texture is used via `samplerCubeArray`, `samplerCubeArrayShadow`,
-the texture is used via `samplerCubeArray`, `samplerCubeArrayShadow`,
 `isamplerCubeArray` or `usamplerCubeArray`. Unlike in classic textures,
 coordinates for cube map texture arrays is signed four-part vector. First three
 parts define vector from the center of the cube which intersects with one of
-the six sides of the cube map, fourth part is layer in the array. See also
+the six sides of the cube map, fourth part is layer in the array. See
 @ref AbstractShaderProgram for more information about usage in shaders.
 
 @see @ref Renderer::Feature::SeamlessCubeMapTexture, @ref CubeMapTexture,

src/Magnum/MultisampleTexture.h

@@ -52,8 +52,7 @@ also @ref AbstractTexture documentation for more information.
 
 @todoc Finish when fully implemented
 
-The texture is bound to layer specified by shader via @ref bind(). In shader,
+In shader, the texture is used via `sampler2DMS`/`sampler2DMSArray`,
-the texture is used via `sampler2DMS`/`sampler2DMSArray`,
 `isampler2DMS`/`isampler2DMSArray` or `usampler2DMS`/`usampler2DMSArray`. See
 @ref AbstractShaderProgram documentation for more information about usage in
 shaders.

src/Magnum/RectangleTexture.h

@@ -59,10 +59,9 @@ texture.setMagnificationFilter(Sampler::Filter::Linear)
     .setSubImage({}, image);
 @endcode
 
-The texture is bound to layer specified by shader via @ref bind(). In shader,
+In shader, the texture is used via sampler2DRect`, `sampler2DRectShadow`,
-the texture is used via sampler2DRect`, `sampler2DRectShadow`, `isampler2DRect`
+`isampler2DRect` or `usampler2DRect`. See @ref AbstractShaderProgram
-or `usampler2DRect`. See @ref AbstractShaderProgram documentation for more
+documentation for more information about usage in shaders.
-information about usage in shaders.
 
 @requires_gl31 %Extension @extension{ARB,texture_rectangle}
 @requires_gl Rectangle textures are not available in OpenGL ES.

src/Magnum/ResourceManager.h

@@ -212,7 +212,7 @@ if(!cube) {
 @endcode
 - Using the resource data.
 @code
-texture->bind(layer);
+shader->setTexture(layer);
 cube->draw(*shader);
 @endcode
 - Destroying resource references and deleting manager instance when nothing

src/Magnum/Shaders/AbstractVector.cpp

@@ -0,0 +1,43 @@
+/*
+    This file is part of Magnum.
+
+    Copyright © 2010, 2011, 2012, 2013, 2014
+              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 "AbstractVector.h"
+
+#include "Magnum/Texture.h"
+#include "Magnum/Shaders/visibility.h"
+
+namespace Magnum { namespace Shaders {
+
+template<UnsignedInt dimensions> AbstractVector<dimensions>& AbstractVector<dimensions>::setVectorTexture(Texture2D& texture) {
+    texture.bind(VectorTextureLayer);
+    return *this;
+}
+
+#ifndef DOXYGEN_GENERATING_OUTPUT
+template class MAGNUM_SHADERS_EXPORT AbstractVector<2>;
+template class MAGNUM_SHADERS_EXPORT AbstractVector<3>;
+#endif
+
+}}

src/Magnum/Shaders/AbstractVector.h

@@ -46,13 +46,29 @@ template<UnsignedInt dimensions> class AbstractVector: public AbstractShaderProg
         /** @brief Texture coordinates */
         typedef typename Generic<dimensions>::TextureCoordinates TextureCoordinates;
 
+        #ifdef MAGNUM_BUILD_DEPRECATED
         enum: Int {
-            VectorTextureLayer = 16 /**< Layer for vector texture */
+            /**
+             * Layer for vector texture
+             * @deprecated Use @ref Magnum::Shaders::AbstractVector::setVectorTexture() "setVectorTexture()" instead.
+             */
+            VectorTextureLayer = 16
         };
+        #endif
+
+        /**
+         * @brief Set vector texture
+         * @return Reference to self (for method chaining)
+         */
+        AbstractVector<dimensions>& setVectorTexture(Texture2D& texture);
 
     protected:
         explicit AbstractVector() = default;
         ~AbstractVector() = default;
+
+        #ifndef MAGNUM_BUILD_DEPRECATED
+        enum: Int { VectorTextureLayer = 16 };
+        #endif
 };
 
 /** @brief Base for two-dimensional text shaders */

src/Magnum/Shaders/CMakeLists.txt

@@ -26,6 +26,7 @@
 corrade_add_resource(MagnumShaders_RCS resources.conf)
 
 set(MagnumShaders_SRCS
+    AbstractVector.cpp
     DistanceFieldVector.cpp
     Flat.cpp
     MeshVisualizer.cpp

src/Magnum/Shaders/DistanceFieldVector.h

@@ -116,6 +116,14 @@ template<UnsignedInt dimensions> class MAGNUM_SHADERS_EXPORT DistanceFieldVector
             return *this;
         }
 
+        #ifndef DOXYGEN_GENERATING_OUTPUT
+        /* Overloads to remove WTF-factor from method chaining order */
+        DistanceFieldVector<dimensions>& setVectorTexture(Texture2D& texture) {
+            AbstractVector<dimensions>::setVectorTexture(texture);
+            return *this;
+        }
+        #endif
+
     private:
         Int transformationProjectionMatrixUniform,
             colorUniform,

src/Magnum/Shaders/Flat.cpp

@@ -30,10 +30,13 @@
 #include "Magnum/Context.h"
 #include "Magnum/Extensions.h"
 #include "Magnum/Shader.h"
+#include "Magnum/Texture.h"
 
 namespace Magnum { namespace Shaders {
 
 namespace {
+    enum: Int { TextureLayer = 0 };
+
     template<UnsignedInt> constexpr const char* vertexShaderName();
     template<> constexpr const char* vertexShaderName<2>() { return "Flat2D.vert"; }
     template<> constexpr const char* vertexShaderName<3>() { return "Flat3D.vert"; }
@@ -96,6 +99,11 @@ template<UnsignedInt dimensions> Flat<dimensions>::Flat(const Flags flags): tran
     #endif
 }
 
+template<UnsignedInt dimensions> Flat<dimensions>& Flat<dimensions>::setTexture(Texture2D& texture) {
+    if(_flags & Flag::Textured)  texture.bind(TextureLayer);
+    return *this;
+}
+
 template class Flat<2>;
 template class Flat<3>;
 

src/Magnum/Shaders/Flat.h

@@ -52,15 +52,9 @@ need to provide @ref Position attribute in your triangle mesh and call at least
 
 If you want to use texture instead of color, you need to provide also
 @ref TextureCoordinates attribute. Pass @ref Flag::Textured to constructor and
-then at render time bind the texture to its respective layer instead of calling
+then at render time don't forget to set also the texture via @ref setTexture().
-@ref setColor(). Example:
+The texture will be multiplied with the color (which is white by default, thus
-@code
+it doesn't change texture color).
-Shaders::Flat2D shader(Shaders::Flat2D::Flag::Textured);
-
-// ...
-
-myTexture.bind(Shaders::Flat2D::TextureLayer);
-@endcode
 
 For coloring the texture based on intensity you can use the @ref Vector shader.
 @see @ref Flat2D, @ref Flat3D
@@ -77,10 +71,15 @@ template<UnsignedInt dimensions> class MAGNUM_SHADERS_EXPORT Flat: public Abstra
          */
         typedef typename Generic<dimensions>::TextureCoordinates TextureCoordinates;
 
+        #ifdef MAGNUM_BUILD_DEPRECATED
         enum: Int {
-            /** Layer for color texture. Used only if @ref Flag::Textured is set. */
+            /**
+             * Layer for color texture. Used only if @ref Flag::Textured is set.
+             * @deprecated use @ref Magnum::Shaders::Flat::setTexture() "setTexture()" instead.
+             */
             TextureLayer = 0
         };
+        #endif
 
         #ifdef DOXYGEN_GENERATING_OUTPUT
         /**
@@ -125,11 +124,21 @@ template<UnsignedInt dimensions> class MAGNUM_SHADERS_EXPORT Flat: public Abstra
          * @brief Set color
          * @return Reference to self (for method chaining)
          *
-         * Color will be multiplied with texture
+         * If not set, default value is fully opaque white. Color will be
-         * if @ref Flag::Textured is set.
+         * multiplied with texture if @ref Flag::Textured is set.
+         * @see @ref setTexture()
          */
         Flat<dimensions>& setColor(const Color4& color);
 
+        /**
+         * @brief Set texture
+         * @return Reference to self (for method chaining)
+         *
+         * Has effect only if @ref Flag::Textured is set.
+         * @see @ref setColor()
+         */
+        Flat<dimensions>& setTexture(Texture2D& texture);
+
     private:
         Int transformationProjectionMatrixUniform,
             colorUniform;

src/Magnum/Shaders/Phong.cpp

@@ -30,9 +30,18 @@
 #include "Magnum/Context.h"
 #include "Magnum/Extensions.h"
 #include "Magnum/Shader.h"
+#include "Magnum/Texture.h"
 
 namespace Magnum { namespace Shaders {
 
+namespace {
+    enum: Int {
+        AmbientTextureLayer = 0,
+        DiffuseTextureLayer = 1,
+        SpecularTextureLayer = 2
+    };
+}
+
 Phong::Phong(const Flags flags): transformationMatrixUniform(0), projectionMatrixUniform(1), normalMatrixUniform(2), lightUniform(3), diffuseColorUniform(4), ambientColorUniform(5), specularColorUniform(6), lightColorUniform(7), shininessUniform(8), _flags(flags) {
     Utility::Resource rs("MagnumShaders");
 
@@ -105,4 +114,19 @@ Phong::Phong(const Flags flags): transformationMatrixUniform(0), projectionMatri
     #endif
 }
 
+Phong& Phong::setAmbientTexture(Texture2D& texture) {
+    if(_flags & Flag::AmbientTexture) texture.bind(AmbientTextureLayer);
+    return *this;
+}
+
+Phong& Phong::setDiffuseTexture(Texture2D& texture) {
+    if(_flags & Flag::DiffuseTexture) texture.bind(DiffuseTextureLayer);
+    return *this;
+}
+
+Phong& Phong::setSpecularTexture(Texture2D& texture) {
+    if(_flags & Flag::SpecularTexture) texture.bind(SpecularTextureLayer);
+    return *this;
+}
+
 }}

src/Magnum/Shaders/Phong.h

@@ -46,15 +46,8 @@ call at least @ref setTransformationMatrix(), @ref setNormalMatrix(),
 
 If you want to use texture instead of color, you need to provide also
 @ref TextureCoordinates attribute. Pass appropriate flags to constructor and
-then at render time bind the texture to its respective layer instead of setting
+then at render time don't forget to also call appropriate subset of
-the color. Example:
+@ref setAmbientTexture(), @ref setDiffuseTexture() and @ref setSpecularTexture().
-@code
-Shaders::Phong shader(Shaders::Phong::Flag::DiffuseTexture);
-
-// ...
-
-myDiffuseTexture.bind(Shaders::Phong::DiffuseTextureLayer);
-@endcode
 */
 class MAGNUM_SHADERS_EXPORT Phong: public AbstractShaderProgram {
     public:
@@ -69,25 +62,33 @@ class MAGNUM_SHADERS_EXPORT Phong: public AbstractShaderProgram {
          */
         typedef Generic3D::TextureCoordinates TextureCoordinates;
 
+        #ifdef MAGNUM_BUILD_DEPRECATED
         enum: Int {
             /**
              * Layer for ambient texture. Used only if @ref Flag::AmbientTexture
              * is set.
+             * @deprecated Use @ref Magnum::Shaders::Phong::setAmbientTexture() "setAmbientTexture()"
+             *      instead.
              */
             AmbientTextureLayer = 0,
 
             /**
              * Layer for diffuse texture. Used only if @ref Flag::DiffuseTexture
              * is set.
+             * @deprecated Use @ref Magnum::Shaders::Phong::setDiffuseTexture() "setDiffuseTexture()"
+             *      instead.
              */
             DiffuseTextureLayer = 1,
 
             /**
              * Layer for specular texture. Used only if @ref Flag::SpecularTexture
              * is set.
+             * @deprecated Use @ref Magnum::Shaders::Phong::setSpecularTexture() "setSpecularTexture()"
+             *      instead.
              */
             SpecularTextureLayer = 2
         };
+        #endif
 
         /**
          * @brief Shader flag
@@ -122,26 +123,56 @@ class MAGNUM_SHADERS_EXPORT Phong: public AbstractShaderProgram {
          *
          * If not set, default value is `(0.0f, 0.0f, 0.0f)`. Has no effect if
          * @ref Flag::AmbientTexture is set.
+         * @see @ref setAmbientTexture()
          */
         Phong& setAmbientColor(const Color3& color);
 
+        /**
+         * @brief Set ambient texture
+         * @return Reference to self (for method chaining)
+         *
+         * Has effect only if @ref Flag::AmbientTexture is set.
+         * @see @ref setAmbientColor()
+         */
+        Phong& setAmbientTexture(Texture2D& texture);
+
         /**
          * @brief Set diffuse color
          * @return Reference to self (for method chaining)
          *
-         * Has no effect if @ref Flag::AmbientTexture is used.
+         * Has no effect if @ref Flag::DiffuseTexture is used.
+         * @see @ref setDiffuseTexture()
          */
         Phong& setDiffuseColor(const Color3& color);
 
+        /**
+         * @brief Set diffuse texture
+         * @return Reference to self (for method chaining)
+         *
+         * Has effect only if @ref Flag::DiffuseTexture is set.
+         * @see @ref setDiffuseColor()
+         */
+        Phong& setDiffuseTexture(Texture2D& texture);
+
         /**
          * @brief Set specular color
          * @return Reference to self (for method chaining)
          *
          * If not set, default value is `(1.0f, 1.0f, 1.0f)`. Has no effect if
          * @ref Flag::SpecularTexture is set.
+         * @see @ref setSpecularTexture()
          */
         Phong& setSpecularColor(const Color3& color);
 
+        /**
+         * @brief Set specular texture
+         * @return Reference to self (for method chaining)
+         *
+         * Has effect only if @ref Flag::SpecularTexture is set.
+         * @see @ref setSpecularColor()
+         */
+        Phong& setSpecularTexture(Texture2D& texture);
+
         /**
          * @brief Set shininess
          * @return Reference to self (for method chaining)

src/Magnum/Shaders/Vector.h

@@ -82,6 +82,14 @@ template<UnsignedInt dimensions> class MAGNUM_SHADERS_EXPORT Vector: public Abst
             return *this;
         }
 
+        #ifndef DOXYGEN_GENERATING_OUTPUT
+        /* Overloads to remove WTF-factor from method chaining order */
+        Vector<dimensions>& setVectorTexture(Texture2D& texture) {
+            AbstractVector<dimensions>::setVectorTexture(texture);
+            return *this;
+        }
+        #endif
+
     private:
         Int transformationProjectionMatrixUniform,
             backgroundColorUniform,

src/Magnum/Text/Renderer.h

@@ -173,8 +173,8 @@ depends on features supported by particular font and its layouter.
 
 Immutable text (e.g. menu items, credits) can be simply rendered using static
 methods, returning result either as data arrays or as fully configured mesh.
-The text can be then drawn by configuring text shader, binding font texture
+The text can be then drawn as usual by configuring the shader and drawing the
-and drawing the mesh:
+mesh:
 @code
 Text::AbstractFont* font;
 Text::GlyphCache cache;
@@ -190,8 +190,8 @@ std::tie(mesh, rectangle) = Text::Renderer2D::render(*font, cache, 0.15f,
 
 // Draw white text centered on the screen
 shader.setTransformationProjectionMatrix(projection*Matrix3::translation(-rectangle.width()/2.0f))
-    .setColor(Color3(1.0f));
+    .setColor(Color3(1.0f))
-glyphCache->texture()->bind(Shaders::VectorShader2D::FontTextureLayer);
+    .setVectorTexture(glyphCache->texture());
 mesh.draw(shader);
 @endcode
 See @ref render(AbstractFont&, const GlyphCache&, Float, const std::string&, Alignment) and
@@ -215,8 +215,8 @@ renderer.render("Hello World Countdown: 10");
 
 // Draw the text centered on the screen
 shader.setTransformationProjectionMatrix(projection*Matrix3::translation(-renderer.rectangle().width()/2.0f))
-    .setColor(Color3(1.0f));
+    .setColor(Color3(1.0f))
-glyphCache->texture()->bind(Shaders::VectorShader2D::FontTextureLayer);
+    .setVectorTexture(glyphCache->texture());
 renderer.mesh().draw(shader);
 @endcode
 

src/Magnum/Texture.h

@@ -82,8 +82,7 @@ texture.setMagnificationFilter(Sampler::Filter::Linear)
     @ref setMinificationFilter(), explicitly specify all mip levels with
     @ref setStorage() and @ref setImage() or call @ref generateMipmap().
 
-The texture is bound to layer specified by shader via @ref bind(). In shader,
+In shader, the texture is used via `sampler1D`/`sampler2D`/`sampler3D`,
-the texture is used via `sampler1D`/`sampler2D`/`sampler3D`,
 `sampler1DShadow`/`sampler2DShadow`/`sampler3DShadow`,
 `isampler1D`/`isampler2D`/`isampler3D` or `usampler1D`/`usampler2D`/`usampler3D`.
 See @ref AbstractShaderProgram documentation for more information about usage

src/Magnum/TextureArray.h

@@ -82,8 +82,7 @@ for(std::size_t i = 0; i != 16; ++i) {
     @ref setMinificationFilter(), explicitly specify all mip levels with
     @ref setStorage() and @ref setImage() or call @ref generateMipmap().
 
-The texture is bound to layer specified by shader via @ref bind(). In shader,
+In shader, the texture is used via `sampler1DArray`/`sampler2DArray`,
-the texture is used via `sampler1DArray`/`sampler2DArray`,
 `sampler1DArrayShadow`/`sampler1DArrayShadow`, `isampler1DArray`/`isampler2DArray`
 or `usampler1DArray`/`usampler2DArray`. See @ref AbstractShaderProgram
 documentation for more information about usage in shaders.

src/Magnum/TextureTools/DistanceField.cpp

@@ -45,10 +45,6 @@ class DistanceFieldShader: public AbstractShaderProgram {
     public:
         typedef Attribute<0, Vector2> Position;
 
-        enum: Int {
-            TextureLayer = 8
-        };
-
         explicit DistanceFieldShader();
 
         DistanceFieldShader& setRadius(Int radius) {
@@ -66,7 +62,14 @@ class DistanceFieldShader: public AbstractShaderProgram {
             return *this;
         }
 
+        DistanceFieldShader& setTexture(Texture2D& texture) {
+            texture.bind(TextureLayer);
+            return *this;
+        }
+
     private:
+        enum: Int { TextureLayer = 8 };
+
         Int radiusUniform,
             scalingUniform,
             imageSizeInvertedUniform;
@@ -162,9 +165,8 @@ void distanceField(Texture2D& input, Texture2D& output, const Range2Di& rectangl
 
     DistanceFieldShader shader;
     shader.setRadius(radius)
-        .setScaling(Vector2(imageSize)/Vector2(rectangle.size()));
+        .setScaling(Vector2(imageSize)/Vector2(rectangle.size()))
-
+        .setTexture(input);
-    input.bind(DistanceFieldShader::TextureLayer);
 
     #ifndef MAGNUM_TARGET_GLES
     if(!Context::current()->isVersionSupported(Version::GL300))