// SPDX-FileCopyrightText: 2014 Citra Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
#pragma once
#include <memory>
#include <utility>
#include "common/common_types.h"
#include "core/frontend/framebuffer_layout.h"
namespace Core::Frontend {
/// Information for the Graphics Backends signifying what type of screen pointer is in
/// WindowInformation
enum class WindowSystemType {
Headless,
Windows,
X11,
Wayland,
Cocoa,
Android,
};
/**
* Represents a drawing context that supports graphics operations.
*/
class GraphicsContext {
public:
virtual ~GraphicsContext();
/// Inform the driver to swap the front/back buffers and present the current image
virtual void SwapBuffers() {}
/// Makes the graphics context current for the caller thread
virtual void MakeCurrent() {}
/// Releases (dunno if this is the "right" word) the context from the caller thread
virtual void DoneCurrent() {}
class Scoped {
public:
[[nodiscard]] explicit Scoped(GraphicsContext& context_) : context(context_) {
context.MakeCurrent();
}
~Scoped() {
if (active) {
context.DoneCurrent();
}
}
/// In the event that context was destroyed before the Scoped is destroyed, this provides a
/// mechanism to prevent calling a destroyed object's method during the deconstructor
void Cancel() {
active = false;
}
private:
GraphicsContext& context;
bool active{true};
};
/// Calls MakeCurrent on the context and calls DoneCurrent when the scope for the returned value
/// ends
[[nodiscard]] Scoped Acquire() {
return Scoped{*this};
}
};
/**
* Abstraction class used to provide an interface between emulation code and the frontend
* (e.g. SDL, QGLWidget, GLFW, etc...).
*
* Design notes on the interaction between EmuWindow and the emulation core:
* - Generally, decisions on anything visible to the user should be left up to the GUI.
* For example, the emulation core should not try to dictate some window title or size.
* This stuff is not the core's business and only causes problems with regards to thread-safety
* anyway.
* - Under certain circumstances, it may be desirable for the core to politely request the GUI
* to set e.g. a minimum window size. However, the GUI should always be free to ignore any
* such hints.
* - EmuWindow may expose some of its state as read-only to the emulation core, however care
* should be taken to make sure the provided information is self-consistent. This requires
* some sort of synchronization (most of this is still a TODO).
* - DO NOT TREAT THIS CLASS AS A GUI TOOLKIT ABSTRACTION LAYER. That's not what it is. Please
* re-read the upper points again and think about it if you don't see this.
*/
class EmuWindow {
public:
/// Data structure to store emuwindow configuration
struct WindowConfig {
bool fullscreen = false;
int res_width = 0;
int res_height = 0;
std::pair<u32, u32> min_client_area_size;
};
/// Data describing host window system information
struct WindowSystemInfo {
// Window system type. Determines which GL context or Vulkan WSI is used.
WindowSystemType type = WindowSystemType::Headless;
// Connection to a display server. This is used on X11 and Wayland platforms.
void* display_connection = nullptr;
// Render surface. This is a pointer to the native window handle, which depends
// on the platform. e.g. HWND for Windows, Window for X11. If the surface is
// set to nullptr, the video backend will run in headless mode.
void* render_surface = nullptr;
// Scale of the render surface. For hidpi systems, this will be >1.
float render_surface_scale = 1.0f;
};
/// Called from GPU thread when a frame is displayed.
virtual void OnFrameDisplayed() {}
/**
* Returns a GraphicsContext that the frontend provides to be used for rendering.
*/
virtual std::unique_ptr<GraphicsContext> CreateSharedContext() const = 0;
/// Returns if window is shown (not minimized)
virtual bool IsShown() const = 0;
/**
* Returns currently active configuration.
* @note Accesses to the returned object need not be consistent because it may be modified in
* another thread
*/
const WindowConfig& GetActiveConfig() const {
return active_config;
}
bool StrictContextRequired() const {
return strict_context_required;
}
/**
* Requests the internal configuration to be replaced by the specified argument at some point in
* the future.
* @note This method is thread-safe, because it delays configuration changes to the GUI event
* loop. Hence there is no guarantee on when the requested configuration will be active.
*/
void SetConfig(const WindowConfig& val) {
config = val;
}
/**
* Returns system information about the drawing area.
*/
const WindowSystemInfo& GetWindowInfo() const {
return window_info;
}
/**
* Gets the framebuffer layout (width, height, and screen regions)
* @note This method is thread-safe
*/
const Layout::FramebufferLayout& GetFramebufferLayout() const {
return framebuffer_layout;
}
/**
* Convenience method to update the current frame layout
* Read from the current settings to determine which layout to use.
*/
void UpdateCurrentFramebufferLayout(u32 width, u32 height);
protected:
explicit EmuWindow();
virtual ~EmuWindow();
/**
* Processes any pending configuration changes from the last SetConfig call.
* This method invokes OnMinimalClientAreaChangeRequest if the corresponding configuration
* field changed.
* @note Implementations will usually want to call this from the GUI thread.
* @todo Actually call this in existing implementations.
*/
void ProcessConfigurationChanges() {
// TODO: For proper thread safety, we should eventually implement a proper
// multiple-writer/single-reader queue...
if (config.min_client_area_size != active_config.min_client_area_size) {
OnMinimalClientAreaChangeRequest(config.min_client_area_size);
config.min_client_area_size = active_config.min_client_area_size;
}
}
/**
* Update framebuffer layout with the given parameter.
* @note EmuWindow implementations will usually use this in window resize event handlers.
*/
void NotifyFramebufferLayoutChanged(const Layout::FramebufferLayout& layout) {
framebuffer_layout = layout;
}
/**
* Update internal client area size with the given parameter.
* @note EmuWindow implementations will usually use this in window resize event handlers.
*/
void NotifyClientAreaSizeChanged(std::pair<u32, u32> size) {
client_area_width = size.first;
client_area_height = size.second;
}
/**
* Converts a screen postion into the equivalent touchscreen position.
*/
std::pair<f32, f32> MapToTouchScreen(u32 framebuffer_x, u32 framebuffer_y) const;
WindowSystemInfo window_info;
bool strict_context_required = false;
private:
/**
* Handler called when the minimal client area was requested to be changed via SetConfig.
* For the request to be honored, EmuWindow implementations will usually reimplement this
* function.
*/
virtual void OnMinimalClientAreaChangeRequest(std::pair<u32, u32>) {
// By default, ignore this request and do nothing.
}
/**
* Clip the provided coordinates to be inside the touchscreen area.
*/
std::pair<u32, u32> ClipToTouchScreen(u32 new_x, u32 new_y) const;
Layout::FramebufferLayout framebuffer_layout; ///< Current framebuffer layout
u32 client_area_width; ///< Current client width, should be set by window impl.
u32 client_area_height; ///< Current client height, should be set by window impl.
WindowConfig config; ///< Internal configuration (changes pending for being applied in
/// ProcessConfigurationChanges)
WindowConfig active_config; ///< Internal active configuration
};
} // namespace Core::Frontend
