Added support for three-component internal formats to BufferedTexture.

It's slight copypaste, because operator| doesn't accept typedefs and
extracting the algorithm from Renderbuffer would cause the code to be
overcomplicated and not prepared for more buffer texture/renderbuffer
format additions.

src/BufferedTexture.cpp

@@ -0,0 +1,52 @@
+/*
+    Copyright © 2010, 2011, 2012 Vladimír Vondruš <mosra@centrum.cz>
+
+    This file is part of Magnum.
+
+    Magnum is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License version 3
+    only, as published by the Free Software Foundation.
+
+    Magnum is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+    GNU Lesser General Public License version 3 for more details.
+*/
+
+#include "BufferedTexture.h"
+
+namespace Magnum {
+
+BufferedTexture::InternalFormat::InternalFormat(Components components, ComponentType type) {
+    #define internalFormatSwitch(c) switch(type) {                          \
+        case ComponentType::UnsignedByte:                                   \
+            internalFormat = GL_##c##8UI; break;                            \
+        case ComponentType::Byte:                                           \
+            internalFormat = GL_##c##8I; break;                             \
+        case ComponentType::UnsignedShort:                                  \
+            internalFormat = GL_##c##16UI; break;                           \
+        case ComponentType::Short:                                          \
+            internalFormat = GL_##c##16I; break;                            \
+        case ComponentType::UnsignedInt:                                    \
+            internalFormat = GL_##c##32UI; break;                           \
+        case ComponentType::Int:                                            \
+            internalFormat = GL_##c##32I; break;                            \
+        case ComponentType::Half:                                           \
+            internalFormat = GL_##c##16F; break;                            \
+        case ComponentType::Float:                                          \
+            internalFormat = GL_##c##32F; break;                            \
+        case ComponentType::NormalizedUnsignedByte:                         \
+            internalFormat = GL_##c##8; break;                              \
+        case ComponentType::NormalizedUnsignedShort:                        \
+            internalFormat = GL_##c##16; break;                             \
+    }
+    if(components == Components::Red)
+        internalFormatSwitch(R)
+    else if(components == Components::RedGreen)
+        internalFormatSwitch(RG)
+    else if(components == Components::RGBA)
+        internalFormatSwitch(RGBA)
+    #undef internalFormatSwitch
+}
+
+}

src/BufferedTexture.h

@@ -45,11 +45,63 @@ class BufferedTexture {
     BufferedTexture& operator=(BufferedTexture&& other) = delete;
 
     public:
+        /** @{ @name Internal buffered texture formats */
+
         /** @copydoc Renderbuffer::Components */
-        typedef Renderbuffer::Components Components;
+        enum class Components {
+            Red, RedGreen, RGBA
+        };
 
         /** @copydoc Renderbuffer::ComponentType */
-        typedef Renderbuffer::ComponentType ComponentType;
+        enum class ComponentType {
+            UnsignedByte, Byte, UnsignedShort, Short, UnsignedInt, Int, Half,
+            Float, NormalizedUnsignedByte, NormalizedUnsignedShort
+        };
+
+        /** @copydoc AbstractTexture::Format */
+        enum class Format: GLenum {
+            /**
+             * Three-component RGB, float, each component 32bit, 96bit total.
+             *
+             * @requires_gl40 Extension <tt>ARB_texture_buffer_object_rgb32</tt>
+             */
+            RGB32Float = GL_RGB32F,
+
+            /**
+             * Three-component RGB, unsigned non-normalized, each component
+             * 32bit, 96bit total.
+             *
+             * @requires_gl40 Extension <tt>ARB_texture_buffer_object_rgb32</tt>
+             */
+            RGB32UnsignedInt = GL_RGB32UI,
+
+            /**
+             * Three-component RGB, signed non-normalized, each component
+             * 32bit, 96bit total.
+             *
+             * @requires_gl40 Extension <tt>ARB_texture_buffer_object_rgb32</tt>
+             */
+            RGB32Int = GL_RGB32I
+        };
+
+        /** @copydoc AbstractTexture::InternalFormat */
+        class MAGNUM_EXPORT InternalFormat {
+            public:
+                /** @copydoc AbstractTexture::InternalFormat::InternalFormat(AbstractTexture::Components, AbstractTexture::ComponentType) */
+                InternalFormat(Components components, ComponentType type);
+
+                /** @copydoc AbstractTexture::InternalFormat::InternalFormat(AbstractTexture::Format) */
+                inline constexpr InternalFormat(Format format): internalFormat(static_cast<GLenum>(format)) {}
+
+                /** @brief OpenGL internal format ID */
+                /* doxygen: @copydoc AbstractTexture::InternalFormat::operator GLint() doesn't work */
+                inline constexpr operator GLint() const { return internalFormat; }
+
+            private:
+                GLint internalFormat;
+        };
+
+        /*@}*/
 
         /**
          * @brief Constructor
@@ -76,17 +128,16 @@ class BufferedTexture {
 
         /**
          * @brief Set texture buffer
-         * @param components    Component count
-         * @param type          Data type per component
-         * @param buffer        %Buffer with data
+         * @param internalFormat    Internal format
+         * @param buffer            %Buffer with data
          *
          * Binds given buffer to this texture. The buffer itself can be then
          * filled with data of proper format at any time using Buffer own data
          * setting functions.
          */
-        void setBuffer(Components components, ComponentType type, Buffer* buffer) {
+        void setBuffer(InternalFormat internalFormat, Buffer* buffer) {
             bind();
-            glTexBuffer(GL_TEXTURE_BUFFER, components|type, buffer->id());
+            glTexBuffer(GL_TEXTURE_BUFFER, internalFormat, buffer->id());
         }
 
     private:
@@ -94,6 +145,15 @@ class BufferedTexture {
         GLuint texture;
 };
 
+/** @copydoc operator|(AbstractTexture::Components, AbstractTexture::ComponentType) */
+inline BufferedTexture::InternalFormat operator|(BufferedTexture::Components components, BufferedTexture::ComponentType type) {
+    return BufferedTexture::InternalFormat(components, type);
+}
+/** @copydoc operator|(AbstractTexture::ComponentType, AbstractTexture::Components) */
+inline BufferedTexture::InternalFormat operator|(BufferedTexture::ComponentType type, BufferedTexture::Components components) {
+    return BufferedTexture::InternalFormat(components, type);
+}
+
 }
 
 #endif

src/CMakeLists.txt

@@ -13,6 +13,7 @@ set(Magnum_SRCS
     AbstractImage.cpp
     AbstractTexture.cpp
     AbstractShaderProgram.cpp
+    BufferedTexture.cpp
     Camera.cpp
     Framebuffer.cpp
     IndexedMesh.cpp