This patch showcases a screen space ambient occlusion

implementation.

rework and add imgui

CMakeLists.txt

@@ -55,6 +55,7 @@ option(WITH_PICKING_EXAMPLE "Build Picking example" OFF)
 option(WITH_PRIMITIVES_EXAMPLE "Build Primitives example" OFF)
 option(WITH_RAYTRACING_EXAMPLE "Build Ray Tracing example" OFF)
 option(WITH_SHADOWS_EXAMPLE "Build Shadow Mapping example" OFF)
+option(WITH_SSAO_EXAMPLE "Build Screen Space Ambient Occlusion Example" OFF)
 option(WITH_TEXT_EXAMPLE "Build Text example (requires some TTF font plugin)" OFF)
 cmake_dependent_option(WITH_TEXTUREDTRIANGLE_EXAMPLE "Build TexturedTriangle example (requires some TGA importer plugin)" OFF "NOT MAGNUM_TARGET_GLES" OFF)
 option(WITH_TRIANGLE_EXAMPLE "Build Triangle example" ON)

src/CMakeLists.txt

@@ -120,6 +120,10 @@ if(WITH_SHADOWS_EXAMPLE)
     add_subdirectory(shadows)
 endif()
 
+if(WITH_SSAO_EXAMPLE)
+    add_subdirectory(ssao)
+endif()
+
 if(WITH_TEXT_EXAMPLE)
     add_subdirectory(text)
 endif()

src/ssao/.gitignore

@@ -0,0 +1,2 @@
+/cmake-*
+.idea/

src/ssao/CMakeLists.txt

@@ -0,0 +1,88 @@
+#
+#   This file is part of Magnum.
+#
+#   Original authors — credit is appreciated but not required:
+#
+#       2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 —
+#           Vladimír Vondruš <mosra@centrum.cz>
+#       2020 — Janos Meny <janos.meny@gmail.com>
+#
+#   This is free and unencumbered software released into the public domain.
+#
+#   Anyone is free to copy, modify, publish, use, compile, sell, or distribute
+#   this software, either in source code form or as a compiled binary, for any
+#   purpose, commercial or non-commercial, and by any means.
+#
+#   In jurisdictions that recognize copyright laws, the author or authors of
+#   this software dedicate any and all copyright interest in the software to
+#   the public domain. We make this dedication for the benefit of the public
+#   at large and to the detriment of our heirs and successors. We intend this
+#   dedication to be an overt act of relinquishment in perpetuity of all
+#   present and future rights to this software under copyright law.
+#
+#   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 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.
+#
+
+cmake_minimum_required(VERSION 3.4)
+
+project(MagnumSSAOExample CXX)
+
+# Add module path in case this is project root
+if(PROJECT_SOURCE_DIR STREQUAL CMAKE_SOURCE_DIR)
+    set(CMAKE_MODULE_PATH "${PROJECT_SOURCE_DIR}/../../modules/" ${CMAKE_MODULE_PATH})
+endif()
+
+set(SSAO_EXAMPLE_DIR ${CMAKE_CURRENT_SOURCE_DIR})
+set(SSAO_EXAMPLE_INSTALL_DIR ${MAGNUM_DATA_INSTALL_DIR}/examples/ssao)
+
+configure_file(${CMAKE_CURRENT_SOURCE_DIR}/configure.h.cmake ${CMAKE_CURRENT_BINARY_DIR}/configure.h)
+
+find_package(Corrade REQUIRED Main)
+find_package(Magnum REQUIRED
+    GL
+    MeshTools
+    Shaders
+    SceneGraph
+    Trade
+    Sdl2Application
+    DebugTools)
+find_package(MagnumIntegration REQUIRED ImGui)
+
+set_directory_properties(PROPERTIES CORRADE_USE_PEDANTIC_FLAGS ON)
+
+corrade_add_resource(SSAO_Rcs Shaders/resources.conf)
+
+add_executable(magnum-ssao WIN32
+        SsaoExample.cpp
+        ../arcball/ArcBall.cpp
+        Shaders/DeferredGeometryShader.cpp
+        Shaders/DeferredGeometryShader.h
+        Shaders/SsaoShader.cpp
+        Shaders/SsaoShader.h
+        Shaders/SsaoApplyShader.cpp
+        Shaders/SsaoApplyShader.h
+        ${SSAO_Rcs})
+
+target_link_libraries(magnum-ssao PRIVATE
+    Corrade::Main
+    Magnum::Application
+    Magnum::GL
+    Magnum::Magnum
+    Magnum::MeshTools
+    Magnum::Trade
+    Magnum::Shaders
+    Magnum::DebugTools
+    MagnumIntegration::ImGui)
+
+target_include_directories(magnum-ssao PRIVATE ${CMAKE_CURRENT_BINARY_DIR})
+
+install(TARGETS magnum-ssao DESTINATION ${MAGNUM_BINARY_INSTALL_DIR})
+install(FILES Armadillo.ply DESTINATION ${MAGNUM_DATA_INSTALL_DIR}/examples/ssao)
+
+# Make the executable a default target to build & run in Visual Studio
+set_property(DIRECTORY ${PROJECT_SOURCE_DIR} PROPERTY VS_STARTUP_PROJECT magnum-ssao)

src/ssao/Shaders/DeferredGeometry.frag

@@ -0,0 +1,47 @@
+/*
+    This file is part of Magnum.
+
+    Original authors — credit is appreciated but not required:
+
+        2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 —
+            Vladimír Vondruš <mosra@centrum.cz>
+        2020 — Janos Meny <janos.meny@gmail.com>
+
+    This is free and unencumbered software released into the public domain.
+
+    Anyone is free to copy, modify, publish, use, compile, sell, or distribute
+    this software, either in source code form or as a compiled binary, for any
+    purpose, commercial or non-commercial, and by any means.
+
+    In jurisdictions that recognize copyright laws, the author or authors of
+    this software dedicate any and all copyright interest in the software to
+    the public domain. We make this dedication for the benefit of the public
+    at large and to the detriment of our heirs and successors. We intend this
+    dedication to be an overt act of relinquishment in perpetuity of all
+    present and future rights to this software under copyright law.
+
+    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 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.
+*/
+
+in highp vec3 viewPosition;
+in highp vec3 viewNormal;
+
+layout(location = 0)
+out highp vec4 color;
+layout(location = 1)
+out highp vec3 position;
+layout(location = 2)
+out highp vec3 normal;
+
+uniform vec4 diffuseColor;
+
+void main() {
+    color = diffuseColor;
+    position = viewPosition;
+    normal = viewNormal;
+}

src/ssao/Shaders/DeferredGeometry.vert

@@ -0,0 +1,49 @@
+/*
+    This file is part of Magnum.
+
+    Original authors — credit is appreciated but not required:
+
+        2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 —
+            Vladimír Vondruš <mosra@centrum.cz>
+        2020 — Janos Meny <janos.meny@gmail.com>
+
+    This is free and unencumbered software released into the public domain.
+
+    Anyone is free to copy, modify, publish, use, compile, sell, or distribute
+    this software, either in source code form or as a compiled binary, for any
+    purpose, commercial or non-commercial, and by any means.
+
+    In jurisdictions that recognize copyright laws, the author or authors of
+    this software dedicate any and all copyright interest in the software to
+    the public domain. We make this dedication for the benefit of the public
+    at large and to the detriment of our heirs and successors. We intend this
+    dedication to be an overt act of relinquishment in perpetuity of all
+    present and future rights to this software under copyright law.
+
+    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 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.
+*/
+
+in highp vec4 position;
+layout(location = 5) //@TODO get rid of layout specifier
+in highp vec3 normal;
+
+uniform mat4 transformation;
+uniform mat3 normalMatrix;
+uniform mat4 projection;
+
+out highp vec3 viewPosition;
+out highp vec3 viewNormal;
+
+void main(){
+   vec4 position4 = transformation*position;
+
+   viewPosition = position4.xyz;
+   viewNormal = normalMatrix*normal;
+
+   gl_Position = projection*position4;
+}

src/ssao/Shaders/DeferredGeometryShader.cpp

@@ -0,0 +1,96 @@
+/*
+    This file is part of Magnum.
+
+    Original authors — credit is appreciated but not required:
+
+        2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 —
+            Vladimír Vondruš <mosra@centrum.cz>
+        2020 — Janos Meny <janos.meny@gmail.com>
+
+    This is free and unencumbered software released into the public domain.
+
+    Anyone is free to copy, modify, publish, use, compile, sell, or distribute
+    this software, either in source code form or as a compiled binary, for any
+    purpose, commercial or non-commercial, and by any means.
+
+    In jurisdictions that recognize copyright laws, the author or authors of
+    this software dedicate any and all copyright interest in the software to
+    the public domain. We make this dedication for the benefit of the public
+    at large and to the detriment of our heirs and successors. We intend this
+    dedication to be an overt act of relinquishment in perpetuity of all
+    present and future rights to this software under copyright law.
+
+    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 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 "DeferredGeometryShader.h"
+
+#include <Corrade/Utility/Resource.h>
+#include <Corrade/Containers/Reference.h>
+
+#include <Magnum/GL/Shader.h>
+#include <Magnum/GL/Version.h>
+#include <Magnum/GL/Context.h>
+#include <Magnum/Math/Matrix4.h>
+#include <Magnum/Math/Matrix3.h>
+#include <Magnum/Math/Color.h>
+
+namespace Magnum { namespace Examples {
+
+DeferredGeometryShader::DeferredGeometryShader() {
+    MAGNUM_ASSERT_GL_VERSION_SUPPORTED(GL::Version::GL330);
+
+    const Utility::Resource rs{"ssao-data"};
+
+    GL::Shader vert{GL::Version::GL330, GL::Shader::Type::Vertex};
+    GL::Shader frag{GL::Version::GL330, GL::Shader::Type::Fragment};
+
+    vert.addSource(rs.get("DeferredGeometry.vert"));
+
+    frag.addSource(rs.get("DeferredGeometry.frag"));
+
+    CORRADE_INTERNAL_ASSERT_OUTPUT(GL::Shader::compile({vert, frag}));
+
+    attachShaders({vert, frag});
+
+    CORRADE_INTERNAL_ASSERT_OUTPUT(link());
+
+    bindAttributeLocation(Position::Location, "position");
+    bindAttributeLocation(Normal::Location, "normal");
+
+    bindFragmentDataLocation(AlbedoOutput, "color");
+    bindFragmentDataLocation(PositionsOutput, "position");
+    bindFragmentDataLocation(NormalsOutput, "normal");
+
+    _transformationUniform = uniformLocation("transformation");
+    _normalMatrixUniform = uniformLocation("normalMatrix");
+    _projectionUniform = uniformLocation("projection");
+    _diffuseColorUniform = uniformLocation("diffuseColor");
+}
+
+DeferredGeometryShader& DeferredGeometryShader::setTransformation(const Matrix4& transformation){
+    setUniform(_transformationUniform, transformation);
+    return *this;
+}
+
+DeferredGeometryShader& DeferredGeometryShader::setNormalMatrix(const Matrix3x3& normalMatrix){
+   setUniform(_normalMatrixUniform, normalMatrix);
+   return *this;
+}
+
+DeferredGeometryShader& DeferredGeometryShader::setProjection(const Matrix4& projection) {
+    setUniform(_projectionUniform, projection);
+    return *this;
+}
+
+DeferredGeometryShader& DeferredGeometryShader::setDiffuseColor(const Color4 &color) {
+    setUniform(_diffuseColorUniform, color);
+    return *this;
+}
+
+}}

src/ssao/Shaders/DeferredGeometryShader.h

@@ -0,0 +1,75 @@
+#ifndef Magnum_Examples_Ssao_DeferredGeometryShader_h
+#define Magnum_Examples_Ssao_DeferredGeometryShader_h
+
+/*
+    This file is part of Magnum.
+
+    Original authors — credit is appreciated but not required:
+
+        2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 —
+            Vladimír Vondruš <mosra@centrum.cz>
+        2020 — Janos Meny <janos.meny@gmail.com>
+
+    This is free and unencumbered software released into the public domain.
+
+    Anyone is free to copy, modify, publish, use, compile, sell, or distribute
+    this software, either in source code form or as a compiled binary, for any
+    purpose, commercial or non-commercial, and by any means.
+
+    In jurisdictions that recognize copyright laws, the author or authors of
+    this software dedicate any and all copyright interest in the software to
+    the public domain. We make this dedication for the benefit of the public
+    at large and to the detriment of our heirs and successors. We intend this
+    dedication to be an overt act of relinquishment in perpetuity of all
+    present and future rights to this software under copyright law.
+
+    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 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 <Magnum/GL/AbstractShaderProgram.h>
+#include <Magnum/Shaders/Generic.h>
+#include <Magnum/GL/GL.h>
+
+namespace Magnum { namespace Examples {
+
+class DeferredGeometryShader : public Magnum::GL::AbstractShaderProgram {
+public:
+
+    using Position = Magnum::Shaders::Generic3D::Position;
+    using Normal = Magnum::Shaders::Generic3D::Normal;
+    using TextureCoordinates = Magnum::Shaders::Generic3D::TextureCoordinates;
+
+    enum {
+        AlbedoOutput = 0,
+        PositionsOutput = 1,
+        NormalsOutput = 2,
+    };
+
+    explicit DeferredGeometryShader(Magnum::NoCreateT) : Magnum::GL::AbstractShaderProgram{Magnum::NoCreate} {};
+
+    explicit DeferredGeometryShader();
+
+    DeferredGeometryShader& setTransformation(const Matrix4& transformation);
+
+    DeferredGeometryShader& setNormalMatrix(const Matrix3x3& normalMatrix);
+
+    DeferredGeometryShader& setProjection(const Matrix4& projection);
+
+    DeferredGeometryShader& setDiffuseColor(const Color4& color);
+
+private:
+
+    Int _transformationUniform,
+        _normalMatrixUniform,
+        _projectionUniform,
+        _diffuseColorUniform;
+};
+
+}}
+
+#endif