Add initial work on Qt frontend

src/duckstation-qt/opengldisplaywindow.h

@@ -0,0 +1,75 @@
+#pragma once
+#include <glad.h>
+
+#include <QtGui/QWindow>
+#include <QtGui/QOpenGLContext>
+#include "common/gl/program.h"
+#include "common/gl/texture.h"
+#include "core/host_display.h"
+#include <string>
+#include <memory>
+
+class OpenGLDisplayWindow final : public QWindow, public HostDisplay
+{
+  Q_OBJECT
+
+public:
+  explicit OpenGLDisplayWindow(QWindow* parent);
+  ~OpenGLDisplayWindow();
+
+  bool createGLContext(QThread* worker_thread);
+  bool initializeGLContext();
+  void destroyGLContext();
+
+  RenderAPI GetRenderAPI() const override;
+  void* GetRenderDevice() const override;
+  void* GetRenderContext() const override;
+  void* GetRenderWindow() const override;
+
+  void ChangeRenderWindow(void* new_window) override;
+
+  std::unique_ptr<HostDisplayTexture> CreateTexture(u32 width, u32 height, const void* data, u32 data_stride,
+                                                    bool dynamic) override;
+  void UpdateTexture(HostDisplayTexture* texture, u32 x, u32 y, u32 width, u32 height, const void* data,
+                     u32 data_stride) override;
+
+  void SetDisplayTexture(void* texture, s32 offset_x, s32 offset_y, s32 width, s32 height, u32 texture_width,
+                         u32 texture_height, float aspect_ratio) override;
+  void SetDisplayLinearFiltering(bool enabled) override;
+  void SetDisplayTopMargin(int height) override;
+
+  void SetVSync(bool enabled) override;
+
+  std::tuple<u32, u32> GetWindowSize() const override;
+  void WindowResized() override;
+
+private:
+  const char* GetGLSLVersionString() const;
+  std::string GetGLSLVersionHeader() const;
+
+  bool CreateImGuiContext();
+  bool CreateGLResources();
+
+  void Render();
+  void RenderDisplay();
+
+  QOpenGLContext* m_gl_context = nullptr;
+
+  GL::Program m_display_program;
+  GLuint m_display_vao = 0;
+  GLuint m_display_texture_id = 0;
+  s32 m_display_offset_x = 0;
+  s32 m_display_offset_y = 0;
+  s32 m_display_width = 0;
+  s32 m_display_height = 0;
+  u32 m_display_texture_width = 0;
+  u32 m_display_texture_height = 0;
+  int m_display_top_margin = 0;
+  float m_display_aspect_ratio = 1.0f;
+  GLuint m_display_nearest_sampler = 0;
+  GLuint m_display_linear_sampler = 0;
+
+  bool m_is_gles = false;
+  bool m_display_texture_changed = false;
+  bool m_display_linear_filtering = false;
+};