LLGL::Surface Class Reference

The Surface interface is the base interface for Window (on Desktop platforms) and Canvas (on mobile platforms). More...

#include <Surface.h>

Inheritance diagram for LLGL::Surface:

Public Member Functions
virtual bool	GetNativeHandle (void *nativeHandle, std::size_t nativeHandleSize)=0
	Returns the native surface handle.
virtual Extent2D	GetContentSize () const =0
	Returns the size (in pixels) of the surface content, i.e. the drawable area.
virtual bool	AdaptForVideoMode (Extent2D *resolution, bool *fullscreen)=0
	Adapts the surface to satisfy the needs for the specified video mode.
virtual Display *	FindResidentDisplay () const =0
	Returns the Display interface in which this surface is resident.
Public Member Functions inherited from LLGL::Interface
virtual bool	IsInstanceOf (int id) const
	Returns true if this object is an instance of the specified interface.
Public Member Functions inherited from LLGL::NonCopyable
	NonCopyable (const NonCopyable &)=delete
NonCopyable &	operator= (const NonCopyable &)=delete
virtual	~NonCopyable ()=default

Static Public Member Functions
static bool	ProcessEvents ()
	Processes all windowing system events, i.e. input-, movement-, resize-, and other events for all surfaces associated with the host process.

Additional Inherited Members
Protected Member Functions inherited from LLGL::NonCopyable
	NonCopyable ()=default

Detailed Description

The Surface interface is the base interface for Window (on Desktop platforms) and Canvas (on mobile platforms).

Remarks

Surface provides the minimal required interface for a graphics rendering context, such as the access to the native handle, information about the content size (i.e. the size of the drawable area), and the ability to adapt for a new video mode.

This is the class custom windowing systems must inherit from either directly or indirectly through the Window or Canvas interface.

See also

Window

Canvas

Member Function Documentation

AdaptForVideoMode()

virtual bool LLGL::Surface::AdaptForVideoMode ( Extent2D * resolution, bool * fullscreen )

pure virtual

Adapts the surface to satisfy the needs for the specified video mode.

Parameters

[in,out]	resolution	Optional pointer to the input and output resolution.
[in,out]	fullscreen	Optional pointer to the fullscreen bit.

Returns

If the video mode has been accepted with no modifications and this surface has been updated then the return value is true. Otherwise, resolution and/or fullscreen arguments have been modified to the value this surface supports and the return value is false.

Implemented in LLGL::Canvas, and LLGL::Window.

FindResidentDisplay()

virtual Display * LLGL::Surface::FindResidentDisplay ( ) const

pure virtual

Returns the Display interface in which this surface is resident.

Remarks

A surface is considered resident in a display if more than the half of its client area is visible in that display.

Returns

Pointer to the Display in which this surface is resident or null if this surface is not resident in any display.

Implemented in LLGL::Canvas, and LLGL::Window.

GetContentSize()

virtual Extent2D LLGL::Surface::GetContentSize ( ) const

pure virtual

Returns the size (in pixels) of the surface content, i.e. the drawable area.

Remarks

On platforms with high-resolution displays, this can be twice or even three times the size of the surface's frame, since the frame's size is given in window coordinates whereas this function provides pixel resolutions.

See also

Window::GetSize

GetNativeHandle()

virtual bool LLGL::Surface::GetNativeHandle ( void * nativeHandle, std::size_t nativeHandleSize )

pure virtual

Returns the native surface handle.

Parameters

[out]	nativeHandle	Raw pointer to the platform specific structure to store the native handle. This must be of type LLGL::NativeHandle.
[in]	nativeHandleSize	Specifies the size (in bytes) of the native handle structure for robustness. This must be sizeof(LLGL::NativeHandle).

Returns

True if the native handle was successfully retrieved. Otherwise, nativeHandleSize specifies an incompatible structure size.

Remarks

This must be casted to a platform specific structure:

// Example for a custom Win32 window class
#include <LLGL/Platform/NativeHandle.h>
//...
bool MyWindowClass::GetNativeHandle(void* nativeHandle, std::size_t nativeHandleSize) {
    if (nativeHandle != nullptr && nativeHandleSize == sizeof(LLGL::NativeHandle)) {
        auto handle = reinterpret_cast<LLGL::NativeHandle*>(nativeHandle);
        //handle->window = 'some HWND window handle';
        return true;
    }
    return false;
}

This is not a constant member function because it might modify internal reference counters. LLGL also has to assume that the returning handle will be used to modify the surface.

ProcessEvents()

bool LLGL::Surface::ProcessEvents ( )

static

Processes all windowing system events, i.e. input-, movement-, resize-, and other events for all surfaces associated with the host process.

Remarks

This should be called once every frame to update all surfaces and their inputs.

Returns

True as long as events can be received. Otherwise, the connection to the window server might have been closed or an error occurred. The return value is mostly used to allow having this function inside a conditional expression to be called before any other event based conditions are invoked, like in the following example:

while (LLGL::Surface::ProcessEvent() && !myWindow->HasQuit()) {
   ...
}

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The documentation for this class was generated from the following file:

• Surface.h