/*
This file is part of Magnum.
Original authors — credit is appreciated but not required:
2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018 —
Vladimír Vondruš <mosra@centrum.cz>
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 <Corrade/Utility/Resource.h>
#include <Magnum/Image.h>
#include <Magnum/PixelFormat.h>
#include <Magnum/GL/AbstractShaderProgram.h>
#include <Magnum/GL/Buffer.h>
#include <Magnum/GL/Context.h>
#include <Magnum/GL/DefaultFramebuffer.h>
#include <Magnum/GL/Framebuffer.h>
#include <Magnum/GL/Mesh.h>
#include <Magnum/GL/Renderbuffer.h>
#include <Magnum/GL/RenderbufferFormat.h>
#include <Magnum/GL/Renderer.h>
#include <Magnum/GL/Shader.h>
#include <Magnum/GL/Texture.h>
#include <Magnum/GL/TextureFormat.h>
#include <Magnum/GL/Version.h>
#include <Magnum/Math/Color.h>
#include <Magnum/MeshTools/CompressIndices.h>
#include <Magnum/MeshTools/Interleave.h>
#include <Magnum/Platform/Sdl2Application.h>
#include <Magnum/Primitives/Cube.h>
#include <Magnum/Primitives/Plane.h>
#include <Magnum/Primitives/UVSphere.h>
#include <Magnum/Trade/MeshData3D.h>
#include <Magnum/SceneGraph/Scene.h>
#include <Magnum/SceneGraph/MatrixTransformation3D.h>
#include <Magnum/SceneGraph/Camera.h>
#include <Magnum/SceneGraph/Drawable.h>
namespace Magnum { namespace Examples {
using namespace Magnum::Math::Literals;
typedef SceneGraph::Object<SceneGraph::MatrixTransformation3D> Object3D;
typedef SceneGraph::Scene<SceneGraph::MatrixTransformation3D> Scene3D;
class PhongIdShader: public GL::AbstractShaderProgram {
public:
typedef GL::Attribute<0, Vector3> Position;
typedef GL::Attribute<1, Vector3> Normal;
enum: UnsignedInt {
ColorOutput = 0,
ObjectIdOutput = 1
};
explicit PhongIdShader();
PhongIdShader& setObjectId(UnsignedInt id) {
setUniform(_objectIdUniform, id);
return *this;
}
PhongIdShader& setLightPosition(const Vector3& position) {
setUniform(_lightPositionUniform, position);
return *this;
}
PhongIdShader& setAmbientColor(const Color3& color) {
setUniform(_ambientColorUniform, color);
return *this;
}
PhongIdShader& setColor(const Color3& color) {
setUniform(_colorUniform, color);
return *this;
}
PhongIdShader& setTransformationMatrix(const Matrix4& matrix) {
setUniform(_transformationMatrixUniform, matrix);
return *this;
}
PhongIdShader& setNormalMatrix(const Matrix3x3& matrix) {
setUniform(_normalMatrixUniform, matrix);
return *this;
}
PhongIdShader& setProjectionMatrix(const Matrix4& matrix) {
setUniform(_projectionMatrixUniform, matrix);
return *this;
}
private:
Int _objectIdUniform,
_lightPositionUniform,
_ambientColorUniform,
_colorUniform,
_transformationMatrixUniform,
_normalMatrixUniform,
_projectionMatrixUniform;
};
PhongIdShader::PhongIdShader() {
Utility::Resource rs("picking-data");
GL::Shader vert{GL::Version::GL330, GL::Shader::Type::Vertex},
frag{GL::Version::GL330, GL::Shader::Type::Fragment};
vert.addSource(rs.get("PhongId.vert"));
frag.addSource(rs.get("PhongId.frag"));
CORRADE_INTERNAL_ASSERT(GL::Shader::compile({vert, frag}));
attachShaders({vert, frag});
CORRADE_INTERNAL_ASSERT(link());
_objectIdUniform = uniformLocation("objectId");
_lightPositionUniform = uniformLocation("light");
_ambientColorUniform = uniformLocation("ambientColor");
_colorUniform = uniformLocation("color");
_transformationMatrixUniform = uniformLocation("transformationMatrix");
_projectionMatrixUniform = uniformLocation("projectionMatrix");
_normalMatrixUniform = uniformLocation("normalMatrix");
}
class PickableObject: public Object3D, SceneGraph::Drawable3D {
public:
explicit PickableObject(UnsignedByte id, PhongIdShader& shader, const Color3& color, GL::Mesh& mesh, Object3D& parent, SceneGraph::DrawableGroup3D& drawables): Object3D{&parent}, SceneGraph::Drawable3D{*this, &drawables}, _id{id}, _selected{false}, _shader(shader), _color{color}, _mesh(mesh) {}
void setSelected(bool selected) { _selected = selected; }
private:
virtual void draw(const Matrix4& transformationMatrix, SceneGraph::Camera3D& camera) {
_shader.setTransformationMatrix(transformationMatrix)
.setNormalMatrix(transformationMatrix.rotationScaling())
.setProjectionMatrix(camera.projectionMatrix())
.setAmbientColor(_selected ? _color*0.3f : Color3{})
.setColor(_color*(_selected ? 2.0f : 1.0f))
/* relative to the camera */
.setLightPosition({13.0f, 2.0f, 5.0f})
.setObjectId(_id);
_mesh.draw(_shader);
}
UnsignedByte _id;
bool _selected;
PhongIdShader& _shader;
Color3 _color;
GL::Mesh& _mesh;
};
class PickingExample: public Platform::Application {
public:
explicit PickingExample(const Arguments& arguments);
private:
void drawEvent() override;
void mousePressEvent(MouseEvent& event) override;
void mouseMoveEvent(MouseMoveEvent& event) override;
void mouseReleaseEvent(MouseEvent& event) override;
Scene3D _scene;
Object3D* _cameraObject;
SceneGraph::Camera3D* _camera;
SceneGraph::DrawableGroup3D _drawables;
PhongIdShader _shader;
GL::Buffer _cubeVertices, _cubeIndices,
_sphereVertices, _sphereIndices,
_planeVertices;
GL::Mesh _cube, _plane, _sphere;
enum { ObjectCount = 6 };
PickableObject* _objects[ObjectCount];
GL::Framebuffer _framebuffer;
GL::Renderbuffer _color, _objectId, _depth;
Vector2i _previousMousePosition, _mousePressPosition;
};
PickingExample::PickingExample(const Arguments& arguments): Platform::Application{arguments, Configuration{}.setTitle("Magnum object picking example")}, _framebuffer{GL::defaultFramebuffer.viewport()} {
MAGNUM_ASSERT_GL_VERSION_SUPPORTED(GL::Version::GL330);
/* Global renderer configuration */
GL::Renderer::enable(GL::Renderer::Feature::DepthTest);
/* Configure framebuffer (using R8UI for object ID which means 255 objects max) */
_color.setStorage(GL::RenderbufferFormat::RGBA8, GL::defaultFramebuffer.viewport().size());
_objectId.setStorage(GL::RenderbufferFormat::R8UI, GL::defaultFramebuffer.viewport().size());
_depth.setStorage(GL::RenderbufferFormat::DepthComponent24, GL::defaultFramebuffer.viewport().size());
_framebuffer.attachRenderbuffer(GL::Framebuffer::ColorAttachment{0}, _color)
.attachRenderbuffer(GL::Framebuffer::ColorAttachment{1}, _objectId)
.attachRenderbuffer(GL::Framebuffer::BufferAttachment::Depth, _depth)
.mapForDraw({{PhongIdShader::ColorOutput, GL::Framebuffer::ColorAttachment{0}},
{PhongIdShader::ObjectIdOutput, GL::Framebuffer::ColorAttachment{1}}});
CORRADE_INTERNAL_ASSERT(_framebuffer.checkStatus(GL::FramebufferTarget::Draw) == GL::Framebuffer::Status::Complete);
/* Set up meshes */
{
Trade::MeshData3D data = Primitives::cubeSolid();
_cubeVertices.setData(MeshTools::interleave(data.positions(0), data.normals(0)), GL::BufferUsage::StaticDraw);
_cubeIndices.setData(MeshTools::compressIndicesAs<UnsignedShort>(data.indices()), GL::BufferUsage::StaticDraw);
_cube.setCount(data.indices().size())
.setPrimitive(data.primitive())
.addVertexBuffer(_cubeVertices, 0, PhongIdShader::Position{}, PhongIdShader::Normal{})
.setIndexBuffer(_cubeIndices, 0, MeshIndexType::UnsignedShort);
} {
Trade::MeshData3D data = Primitives::uvSphereSolid(16, 32);
_sphereVertices.setData(MeshTools::interleave(data.positions(0), data.normals(0)), GL::BufferUsage::StaticDraw);
_sphereIndices.setData(MeshTools::compressIndicesAs<UnsignedShort>(data.indices()), GL::BufferUsage::StaticDraw);
_sphere.setCount(data.indices().size())
.setPrimitive(data.primitive())
.addVertexBuffer(_sphereVertices, 0, PhongIdShader::Position{}, PhongIdShader::Normal{})
.setIndexBuffer(_sphereIndices, 0, MeshIndexType::UnsignedShort);
} {
Trade::MeshData3D data = Primitives::planeSolid();
_planeVertices.setData(MeshTools::interleave(data.positions(0), data.normals(0)), GL::BufferUsage::StaticDraw);
_plane.setCount(data.positions(0).size())
.setPrimitive(data.primitive())
.addVertexBuffer(_planeVertices, 0, PhongIdShader::Position{}, PhongIdShader::Normal{});
}
/* Set up objects */
(*(_objects[0] = new PickableObject{1, _shader, 0x3bd267_rgbf, _cube, _scene, _drawables}))
.rotate(34.0_degf, Vector3(1.0f).normalized())
.translate({1.0f, 0.3f, -1.2f});
(*(_objects[1] = new PickableObject{2, _shader, 0x2f83cc_rgbf, _sphere, _scene, _drawables}))
.translate({-1.2f, -0.3f, -0.2f});
(*(_objects[2] = new PickableObject{3, _shader, 0xdcdcdc_rgbf, _plane, _scene, _drawables}))
.rotate(278.0_degf, Vector3(1.0f).normalized())
.scale(Vector3(0.45f))
.translate({-1.0f, 1.2f, 1.5f});
(*(_objects[3] = new PickableObject{4, _shader, 0xc7cf2f_rgbf, _sphere, _scene, _drawables}))
.translate({-0.2f, -1.7f, -2.7f});
(*(_objects[4] = new PickableObject{5, _shader, 0xcd3431_rgbf, _sphere, _scene, _drawables}))
.translate({0.7f, 0.6f, 2.2f})
.scale(Vector3(0.75f));
(*(_objects[5] = new PickableObject{6, _shader, 0xa5c9ea_rgbf, _cube, _scene, _drawables}))
.rotate(-92.0_degf, Vector3(1.0f).normalized())
.scale(Vector3(0.25f))
.translate({-0.5f, -0.3f, 1.8f});
/* Configure camera */
_cameraObject = new Object3D{&_scene};
_cameraObject->translate(Vector3::zAxis(8.0f));
_camera = new SceneGraph::Camera3D{*_cameraObject};
_camera->setAspectRatioPolicy(SceneGraph::AspectRatioPolicy::Extend)
.setProjectionMatrix(Matrix4::perspectiveProjection(35.0_degf, 4.0f/3.0f, 0.001f, 100.0f))
.setViewport(GL::defaultFramebuffer.viewport().size());
}
void PickingExample::drawEvent() {
/* Draw to custom framebuffer */
_framebuffer
.clearColor(0, Color3{0.125f})
.clearColor(1, Vector4ui{})
.clearDepth(1.0f)
.bind();
_camera->draw(_drawables);
/* Bind the main buffer back */
GL::defaultFramebuffer.clear(GL::FramebufferClear::Color|GL::FramebufferClear::Depth)
.bind();
/* Blit color to window framebuffer */
_framebuffer.mapForRead(GL::Framebuffer::ColorAttachment{0});
GL::AbstractFramebuffer::blit(_framebuffer, GL::defaultFramebuffer,
{{}, _framebuffer.viewport().size()}, GL::FramebufferBlit::Color);
swapBuffers();
}
void PickingExample::mousePressEvent(MouseEvent& event) {
if(event.button() != MouseEvent::Button::Left) return;
_previousMousePosition = _mousePressPosition = event.position();
event.setAccepted();
}
void PickingExample::mouseMoveEvent(MouseMoveEvent& event) {
if(!(event.buttons() & MouseMoveEvent::Button::Left)) return;
const Vector2 delta = 3.0f*
Vector2{event.position() - _previousMousePosition}/
Vector2{GL::defaultFramebuffer.viewport().size()};
(*_cameraObject)
.rotate(Rad{-delta.y()}, _cameraObject->transformation().right().normalized())
.rotateY(Rad{-delta.x()});
_previousMousePosition = event.position();
event.setAccepted();
redraw();
}
void PickingExample::mouseReleaseEvent(MouseEvent& event) {
if(event.button() != MouseEvent::Button::Left || _mousePressPosition != event.position()) return;
/* Read object ID at given click position (framebuffer has Y up while windowing system Y down) */
_framebuffer.mapForRead(GL::Framebuffer::ColorAttachment{1});
Image2D data = _framebuffer.read(
Range2Di::fromSize({event.position().x(), _framebuffer.viewport().sizeY() - event.position().y() - 1}, {1, 1}),
{PixelFormat::R8UI});
/* Highlight object under mouse and deselect all other */
for(auto* o: _objects) o->setSelected(false);
UnsignedByte id = data.data<UnsignedByte>()[0];
if(id > 0 && id < ObjectCount + 1)
_objects[id - 1]->setSelected(true);
event.setAccepted();
redraw();
}
}}
MAGNUM_APPLICATION_MAIN(Magnum::Examples::PickingExample)