// Copyright 2014 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#pragma once
#include <memory>
#include <tuple>
#include <utility>
#include "common/common_types.h"
#include "core/frontend/framebuffer_layout.h"
namespace Core::Frontend {
/**
* Represents a graphics context that can be used for background computation or drawing. If the
* graphics backend doesn't require the context, then the implementation of these methods can be
* stubs
*/
class GraphicsContext {
public:
/// Makes the graphics context current for the caller thread
virtual void MakeCurrent() = 0;
/// Releases (dunno if this is the "right" word) the context from the caller thread
virtual void DoneCurrent() = 0;
/// Swap buffers to display the next frame
virtual void SwapBuffers() = 0;
};
/**
* 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 GraphicsContext {
public:
/// Data structure to store emuwindow configuration
struct WindowConfig {
bool fullscreen = false;
int res_width = 0;
int res_height = 0;
std::pair<unsigned, unsigned> min_client_area_size;
};
/// Polls window events
virtual void PollEvents() = 0;
/**
* Returns a GraphicsContext that the frontend provides that is shared with the emu window. This
* context can be used from other threads for background graphics computation. If the frontend
* is using a graphics backend that doesn't need anything specific to run on a different thread,
* then it can use a stubbed implemenation for GraphicsContext.
*
* If the return value is null, then the core should assume that the frontend cannot provide a
* Shared Context
*/
virtual std::unique_ptr<GraphicsContext> CreateSharedContext() const {
return nullptr;
}
/**
* Signal that a touch pressed event has occurred (e.g. mouse click pressed)
* @param framebuffer_x Framebuffer x-coordinate that was pressed
* @param framebuffer_y Framebuffer y-coordinate that was pressed
*/
void TouchPressed(unsigned framebuffer_x, unsigned framebuffer_y);
/// Signal that a touch released event has occurred (e.g. mouse click released)
void TouchReleased();
/**
* Signal that a touch movement event has occurred (e.g. mouse was moved over the emu window)
* @param framebuffer_x Framebuffer x-coordinate
* @param framebuffer_y Framebuffer y-coordinate
*/
void TouchMoved(unsigned framebuffer_x, unsigned framebuffer_y);
/**
* 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;
}
/**
* 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;
}
/**
* 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(unsigned width, unsigned height);
protected:
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(const std::pair<unsigned, unsigned>& size) {
client_area_width = size.first;
client_area_height = size.second;
}
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(
const std::pair<unsigned, unsigned>& minimal_size) {
// By default, ignore this request and do nothing.
}
Layout::FramebufferLayout framebuffer_layout; ///< Current framebuffer layout
unsigned client_area_width; ///< Current client width, should be set by window impl.
unsigned 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
class TouchState;
std::shared_ptr<TouchState> touch_state;
/**
* Clip the provided coordinates to be inside the touchscreen area.
*/
std::tuple<unsigned, unsigned> ClipToTouchScreen(unsigned new_x, unsigned new_y);
};
} // namespace Core::Frontend