Big bang

src/magnum_item.cpp

@@ -0,0 +1,81 @@
+#include <Magnum/GL/Framebuffer.h>
+#include <Magnum/Platform/GLContext.h>
+#include <QtCore/QRunnable>
+#include <QtQuick/QQuickWindow>
+#include <QOpenGLFramebufferObject>
+#include "magnum_item.h"
+#include "magnum_render.h"
+
+using namespace std;
+using namespace Magnum;
+using namespace Math::Literals;
+
+class MagnumFBORenderer : public QQuickFramebufferObject::Renderer {
+public:
+  MagnumFBORenderer(QQuickWindow *window, MagnumRenderer *renderer) :
+    m_window(window),
+    m_renderer(renderer) {}
+
+  void render() override {
+    m_renderer->render();
+    m_window->resetOpenGLState();
+    update();
+  }
+
+  void synchronize(QQuickFramebufferObject *item) override {
+    auto mitem = static_cast<MagnumItem*>(item);
+    m_renderer->hue(mitem->hue());
+  }
+
+  QOpenGLFramebufferObject *createFramebufferObject(const QSize &size) override {
+    QOpenGLFramebufferObjectFormat format;
+    format.setAttachment(QOpenGLFramebufferObject::CombinedDepthStencil);
+    format.setSamples(4);
+    m_fbo = new QOpenGLFramebufferObject(size, format);
+    if (m_ctx == nullptr)
+      m_ctx = new Platform::GLContext();
+    Platform::GLContext::makeCurrent(m_ctx);
+    m_renderer->reset(
+          m_ctx,
+          GL::Framebuffer::wrap(
+            m_fbo->handle(), {{}, {size.width(),
+                                   size.height()}}));
+    return m_fbo;
+  }
+
+private:
+  QQuickWindow *m_window;
+  QOpenGLFramebufferObject *m_fbo;
+  Platform::GLContext *m_ctx{};
+  MagnumRenderer *m_renderer;
+};
+
+MagnumItem::MagnumItem() : m_renderer(new MagnumRenderer()) {
+  setMirrorVertically(true);
+}
+
+QQuickFramebufferObject::Renderer *MagnumItem::createRenderer() const {
+  return new MagnumFBORenderer(window(), m_renderer);
+}
+
+void MagnumItem::setHue(qreal hue) {
+  if (hue == m_hue) return;
+  m_hue = hue;
+  emit hueChanged();
+  update();
+}
+
+class CleanupJob : public QRunnable {
+public:
+  CleanupJob(MagnumRenderer *renderer) : m_renderer(renderer) {}
+  void run() override { delete m_renderer; }
+private:
+  MagnumRenderer *m_renderer;
+};
+
+void MagnumItem::releaseResources() {
+  window()->scheduleRenderJob(
+        new CleanupJob(m_renderer),
+        QQuickWindow::BeforeSynchronizingStage);
+  m_renderer = nullptr;
+}