Platform: ability to specify color/depth/stencil buffer sizes.

doc/changelog.dox

@@ -59,6 +59,12 @@ See also:
 
 -   Implemented @ref Platform::GlfwApplication::MouseMoveEvent::buttons() for
     feature parity with @ref Platform::Sdl2Application
+-   Added @ref Platform::Sdl2Application::GLConfiguration::setColorBufferSize() "GLConfiguration::setColorBufferSize()",
+    @ref Platform::Sdl2Application::GLConfiguration::setDepthBufferSize() "GLConfiguration::setDepthBufferSize()",
+    @ref Platform::Sdl2Application::GLConfiguration::setStencilBufferSize() "GLConfiguration::setStencilBufferSize()",
+    to @ref Platform::Sdl2Application, @ref Platform::GlfwApplication and
+    @ref Platform::AndroidApplication. This also makes the default framebuffer
+    parameters consistent across the implementations.
 
 @subsection changelog-latest-changes Changes and improvements
 

src/Magnum/Platform/AndroidApplication.cpp

@@ -98,7 +98,7 @@ bool AndroidApplication::tryCreate(const Configuration& configuration) {
     return tryCreate(configuration, GLConfiguration{});
 }
 
-bool AndroidApplication::tryCreate(const Configuration& configuration, const GLConfiguration&) {
+bool AndroidApplication::tryCreate(const Configuration& configuration, const GLConfiguration& glConfiguration) {
     CORRADE_ASSERT(_context->version() == GL::Version::None, "Platform::AndroidApplication::tryCreate(): context already created", false);
 
     /* Initialize EGL */
@@ -112,10 +112,12 @@ bool AndroidApplication::tryCreate(const Configuration& configuration, const GLC
     /* Choose config */
     const EGLint configAttributes[] = {
         EGL_SURFACE_TYPE, EGL_WINDOW_BIT,
-        EGL_BLUE_SIZE, 8,
-        EGL_GREEN_SIZE, 8,
-        EGL_RED_SIZE, 8,
-        EGL_DEPTH_SIZE, 24,
+        EGL_RED_SIZE, glConfiguration.colorBufferSize().r(),
+        EGL_GREEN_SIZE, glConfiguration.colorBufferSize().g(),
+        EGL_BLUE_SIZE, glConfiguration.colorBufferSize().b(),
+        EGL_ALPHA_SIZE, glConfiguration.colorBufferSize().a(),
+        EGL_DEPTH_SIZE, glConfiguration.depthBufferSize(),
+        EGL_STENCIL_SIZE, glConfiguration.stencilBufferSize(),
         EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
         EGL_NONE
     };
@@ -242,6 +244,9 @@ std::int32_t AndroidApplication::inputEvent(android_app* state, AInputEvent* eve
     return 0;
 }
 
+AndroidApplication::GLConfiguration::GLConfiguration():
+    _colorBufferSize{8, 8, 8, 0}, _depthBufferSize{24}, _stencilBufferSize{0} {}
+
 void AndroidApplication::exec(android_app* state, std::unique_ptr<AndroidApplication>(*instancer)(const Arguments&)) {
     state->onAppCmd = commandEvent;
     state->onInputEvent = inputEvent;

src/Magnum/Platform/AndroidApplication.h

@@ -37,7 +37,7 @@
 #include "Magnum/Magnum.h"
 #include "Magnum/Tags.h"
 #include "Magnum/GL/GL.h"
-#include "Magnum/Math/Vector2.h"
+#include "Magnum/Math/Vector4.h"
 #include "Magnum/Platform/Platform.h"
 
 #if defined(CORRADE_TARGET_ANDROID) || defined(DOXYGEN_GENERATING_OUTPUT)
@@ -393,7 +393,7 @@ Double-buffered RGBA canvas with depth and stencil buffers.
 */
 class AndroidApplication::GLConfiguration {
     public:
-        constexpr /*implicit*/ GLConfiguration() {}
+        /*implicit*/ GLConfiguration();
 
         /**
          * @brief Set context version
@@ -404,6 +404,52 @@ class AndroidApplication::GLConfiguration {
          *      settings.
          */
         GLConfiguration& setVersion(GL::Version) { return *this; }
+
+        /** @brief Color buffer size */
+        Vector4i colorBufferSize() const { return _colorBufferSize; }
+
+        /**
+         * @brief Set color buffer size
+         *
+         * Default is @cpp {8, 8, 8, 0} @ce (8-bit-per-channel RGB, no alpha).
+         * @see @ref setDepthBufferSize(), @ref setStencilBufferSize()
+         */
+        GLConfiguration& setColorBufferSize(const Vector4i& size) {
+            _colorBufferSize = size;
+            return *this;
+        }
+
+        /** @brief Depth buffer size */
+        Int depthBufferSize() const { return _depthBufferSize; }
+
+        /**
+         * @brief Set depth buffer size
+         *
+         * Default is @cpp 24 @ce bits.
+         * @see @ref setColorBufferSize(), @ref setStencilBufferSize()
+         */
+        GLConfiguration& setDepthBufferSize(Int size) {
+            _depthBufferSize = size;
+            return *this;
+        }
+
+        /** @brief Stencil buffer size */
+        Int stencilBufferSize() const { return _stencilBufferSize; }
+
+        /**
+         * @brief Set stencil buffer size
+         *
+         * Default is @cpp 0 @ce bits (i.e., no stencil buffer).
+         * @see @ref setColorBufferSize(), @ref setDepthBufferSize()
+         */
+        GLConfiguration& setStencilBufferSize(Int size) {
+            _stencilBufferSize = size;
+            return *this;
+        }
+
+    private:
+        Vector4i _colorBufferSize;
+        Int _depthBufferSize, _stencilBufferSize;
 };
 
 /**

src/Magnum/Platform/GlfwApplication.cpp

@@ -210,7 +210,13 @@ bool GlfwApplication::tryCreate(const Configuration& configuration, const GLConf
     }
     glfwWindowHint(GLFW_FOCUSED, configuration.windowFlags() >= Configuration::WindowFlag::Focused);
 
-    /* Context window hints */
+    /* Framebuffer setup */
+    glfwWindowHint(GLFW_RED_BITS, glConfiguration.colorBufferSize().r());
+    glfwWindowHint(GLFW_GREEN_BITS, glConfiguration.colorBufferSize().g());
+    glfwWindowHint(GLFW_BLUE_BITS, glConfiguration.colorBufferSize().b());
+    glfwWindowHint(GLFW_ALPHA_BITS, glConfiguration.colorBufferSize().a());
+    glfwWindowHint(GLFW_DEPTH_BITS, glConfiguration.depthBufferSize());
+    glfwWindowHint(GLFW_STENCIL_BITS, glConfiguration.stencilBufferSize());
     glfwWindowHint(GLFW_SAMPLES, glConfiguration.sampleCount());
     glfwWindowHint(GLFW_SRGB_CAPABLE, glConfiguration.isSRGBCapable());
 
@@ -473,7 +479,9 @@ void GlfwApplication::mouseScrollEvent(MouseScrollEvent&) {}
 void GlfwApplication::textInputEvent(TextInputEvent&) {}
 
 #ifdef MAGNUM_TARGET_GL
-GlfwApplication::GLConfiguration::GLConfiguration(): _sampleCount{0}, _version{GL::Version::None} {}
+GlfwApplication::GLConfiguration::GLConfiguration():
+    _colorBufferSize{8, 8, 8, 0}, _depthBufferSize{24}, _stencilBufferSize{0},
+    _sampleCount{0}, _version{GL::Version::None} {}
 
 GlfwApplication::GLConfiguration::~GLConfiguration() = default;
 #endif

src/Magnum/Platform/GlfwApplication.h

@@ -37,7 +37,7 @@
 
 #include "Magnum/Magnum.h"
 #include "Magnum/Tags.h"
-#include "Magnum/Math/Vector2.h"
+#include "Magnum/Math/Vector4.h"
 #include "Magnum/Platform/Platform.h"
 
 #ifdef MAGNUM_TARGET_GL
@@ -482,7 +482,7 @@ CORRADE_ENUMSET_OPERATORS(GlfwApplication::Flags)
 /**
 @brief OpenGL context configuration
 
-Double-buffered RGBA window with depth and stencil buffers.
+The created window is always with double-buffered OpenGL context.
 
 @note This function is available only if Magnum is compiled with
     @ref MAGNUM_TARGET_GL enabled (done by default). See @ref building-features
@@ -553,6 +553,48 @@ class GlfwApplication::GLConfiguration {
             return *this;
         }
 
+        /** @brief Color buffer size */
+        Vector4i colorBufferSize() const { return _colorBufferSize; }
+
+        /**
+         * @brief Set color buffer size
+         *
+         * Default is @cpp {8, 8, 8, 0} @ce (8-bit-per-channel RGB, no alpha).
+         * @see @ref setDepthBufferSize(), @ref setStencilBufferSize()
+         */
+        GLConfiguration& setColorBufferSize(const Vector4i& size) {
+            _colorBufferSize = size;
+            return *this;
+        }
+
+        /** @brief Depth buffer size */
+        Int depthBufferSize() const { return _depthBufferSize; }
+
+        /**
+         * @brief Set depth buffer size
+         *
+         * Default is @cpp 24 @ce bits.
+         * @see @ref setColorBufferSize(), @ref setStencilBufferSize()
+         */
+        GLConfiguration& setDepthBufferSize(Int size) {
+            _depthBufferSize = size;
+            return *this;
+        }
+
+        /** @brief Stencil buffer size */
+        Int stencilBufferSize() const { return _stencilBufferSize; }
+
+        /**
+         * @brief Set stencil buffer size
+         *
+         * Default is @cpp 0 @ce bits (i.e., no stencil buffer).
+         * @see @ref setColorBufferSize(), @ref setDepthBufferSize()
+         */
+        GLConfiguration& setStencilBufferSize(Int size) {
+            _stencilBufferSize = size;
+            return *this;
+        }
+
         /** @brief Sample count */
         Int sampleCount() const { return _sampleCount; }
 
@@ -584,6 +626,8 @@ class GlfwApplication::GLConfiguration {
         }
 
     private:
+        Vector4i _colorBufferSize;
+        Int _depthBufferSize, _stencilBufferSize;
         Int _sampleCount;
         GL::Version _version;
         Flags _flags;

src/Magnum/Platform/Sdl2Application.cpp

@@ -166,9 +166,14 @@ bool Sdl2Application::tryCreate(const Configuration& configuration, const GLConf
 
     CORRADE_ASSERT(_context->version() == GL::Version::None, "Platform::Sdl2Application::tryCreate(): context already created", false);
 
-    /* Enable double buffering and 24bt depth buffer */
+    /* Enable double buffering, set up buffer sizes */
     SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
-    SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
+    SDL_GL_SetAttribute(SDL_GL_RED_SIZE, glConfiguration.colorBufferSize().r());
+    SDL_GL_SetAttribute(SDL_GL_GREEN_SIZE, glConfiguration.colorBufferSize().g());
+    SDL_GL_SetAttribute(SDL_GL_BLUE_SIZE, glConfiguration.colorBufferSize().b());
+    SDL_GL_SetAttribute(SDL_GL_ALPHA_SIZE, glConfiguration.colorBufferSize().a());
+    SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, glConfiguration.depthBufferSize());
+    SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, glConfiguration.stencilBufferSize());
 
     /* Multisampling */
     SDL_GL_SetAttribute(SDL_GL_MULTISAMPLEBUFFERS, glConfiguration.sampleCount() > 1 ? 1 : 0);
@@ -613,6 +618,7 @@ void Sdl2Application::textEditingEvent(TextEditingEvent&) {}
 
 #ifdef MAGNUM_TARGET_GL
 Sdl2Application::GLConfiguration::GLConfiguration():
+    _colorBufferSize{8, 8, 8, 0}, _depthBufferSize{24}, _stencilBufferSize{0},
     _sampleCount(0)
     #ifndef CORRADE_TARGET_EMSCRIPTEN
     , _version(GL::Version::None), _sRGBCapable{false}

src/Magnum/Platform/Sdl2Application.h

@@ -36,7 +36,7 @@
 
 #include "Magnum/Magnum.h"
 #include "Magnum/Tags.h"
-#include "Magnum/Math/Vector2.h"
+#include "Magnum/Math/Vector4.h"
 #include "Magnum/Platform/Platform.h"
 
 #ifdef MAGNUM_TARGET_GL
@@ -836,8 +836,7 @@ class Sdl2Application {
 /**
 @brief OpenGL context configuration
 
-The created window is always with double-buffered OpenGL context and 24bit
-depth buffer.
+The created window is always with double-buffered OpenGL context.
 
 @note This function is available only if Magnum is compiled with
     @ref MAGNUM_TARGET_GL enabled (done by default). See @ref building-features
@@ -931,6 +930,48 @@ class Sdl2Application::GLConfiguration {
             return *this;
         }
 
+        /** @brief Color buffer size */
+        Vector4i colorBufferSize() const { return _colorBufferSize; }
+
+        /**
+         * @brief Set color buffer size
+         *
+         * Default is @cpp {8, 8, 8, 0} @ce (8-bit-per-channel RGB, no alpha).
+         * @see @ref setDepthBufferSize(), @ref setStencilBufferSize()
+         */
+        GLConfiguration& setColorBufferSize(const Vector4i& size) {
+            _colorBufferSize = size;
+            return *this;
+        }
+
+        /** @brief Depth buffer size */
+        Int depthBufferSize() const { return _depthBufferSize; }
+
+        /**
+         * @brief Set depth buffer size
+         *
+         * Default is @cpp 24 @ce bits.
+         * @see @ref setColorBufferSize(), @ref setStencilBufferSize()
+         */
+        GLConfiguration& setDepthBufferSize(Int size) {
+            _depthBufferSize = size;
+            return *this;
+        }
+
+        /** @brief Stencil buffer size */
+        Int stencilBufferSize() const { return _stencilBufferSize; }
+
+        /**
+         * @brief Set stencil buffer size
+         *
+         * Default is @cpp 0 @ce bits (i.e., no stencil buffer).
+         * @see @ref setColorBufferSize(), @ref setDepthBufferSize()
+         */
+        GLConfiguration& setStencilBufferSize(Int size) {
+            _stencilBufferSize = size;
+            return *this;
+        }
+
         /** @brief Sample count */
         Int sampleCount() const { return _sampleCount; }
 
@@ -969,6 +1010,8 @@ class Sdl2Application::GLConfiguration {
         #endif
 
     private:
+        Vector4i _colorBufferSize;
+        Int _depthBufferSize, _stencilBufferSize;
         Int _sampleCount;
         #ifndef CORRADE_TARGET_EMSCRIPTEN
         GL::Version _version;