CppPaintingAgents/src/Platform/Win32/WindowsPlatform.cpp

#ifdef _WIN32
	#include "Platform/Win32/WindowsPlatform.hpp"

	#include "Resource.h"

namespace util
{
/******************************************************************************
 *
 *****************************************************************************/
WindowsPlatform::WindowsPlatform()
{
	// Get the default device info
	m_screenScalingFactor = getScreenScalingFactor(nullptr);
	m_refreshRate = getRefreshRate(nullptr);
}

/******************************************************************************
 * The window handle uses 32x32 (ICON_BIG) & 16x16 (ICON_SMALL) sized icons.
 * This should be called any time the SFML window is create/recreated
 *****************************************************************************/
void WindowsPlatform::setIcon(const sf::WindowHandle& inHandle)
{
	// Get the icon directory
	PBYTE iconDirectory = getIconDirectory(WIN32_ICON_MAIN);
	std::array<int, 5> icons = { 16, 32, 48, 64, 128 };

	std::size_t indexSmallIcon = static_cast<std::size_t>(std::min(std::max(std::ceil(m_screenScalingFactor - 1.0f), 0.0f), static_cast<float>(icons.size()) - 1.0f));
	std::size_t indexBigIcon = static_cast<std::size_t>(std::min(std::max(std::ceil(m_screenScalingFactor - 1.0f), 0.0f) + 1.0f, static_cast<float>(icons.size()) - 1.0f));

	HICON smallIcon = getIconFromIconDirectory(iconDirectory, icons[indexSmallIcon]);
	HICON bigIcon = getIconFromIconDirectory(iconDirectory, icons[indexBigIcon]);

	if (smallIcon)
		SendMessage(inHandle, WM_SETICON, ICON_SMALL, (LPARAM)smallIcon);

	if (bigIcon)
		SendMessage(inHandle, WM_SETICON, ICON_BIG, (LPARAM)bigIcon);

	// https://docs.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-destroyicon
	// It is only necessary to call DestroyIcon for icons and cursors created with the following functions:
	//   CreateIconFromResourceEx (if called without the LR_SHARED flag)
}

/******************************************************************************
 *
 *****************************************************************************/
void WindowsPlatform::toggleFullscreen(const sf::WindowHandle& inHandle, const sf::Uint32 inStyle, const bool inWindowed, const sf::Vector2u& inResolution)
{
	DWORD win32Style = sfmlWindowStyleToWin32WindowStyle(inStyle);
	UINT flags = SWP_DRAWFRAME | SWP_FRAMECHANGED;

	if (inWindowed)
	{
		// Window (centered on the focused screen)
		HDC screenDC = GetDC(inHandle);
		int screenWidth = GetDeviceCaps(screenDC, HORZRES);
		int screenHeight = GetDeviceCaps(screenDC, VERTRES);
		ReleaseDC(inHandle, screenDC);

		int width = static_cast<int>(inResolution.x);
		int height = static_cast<int>(inResolution.y);
		int left = (screenWidth - width) / 2;
		int top = (screenHeight - height) / 2;
		RECT rectangle = { 0, 0, width, height };
		AdjustWindowRect(&rectangle, win32Style, false);
		width = rectangle.right - rectangle.left;
		height = rectangle.bottom - rectangle.top;

		SetWindowLongPtr(inHandle, GWL_STYLE, win32Style);
		SetWindowLongPtr(inHandle, GWL_EXSTYLE, 0);
		SetWindowPos(inHandle, nullptr, left, top, width, height, flags);
	}
	else
	{
		// Fullscreen
		int width = static_cast<int>(inResolution.x);
		int height = static_cast<int>(inResolution.y);

		// first time prevents the border from showing in the corner
		SetWindowPos(inHandle, HWND_TOP, 0, 0, width, height, flags);
		SetWindowLongPtr(inHandle, GWL_EXSTYLE, WS_EX_APPWINDOW);
		SetWindowLongPtr(inHandle, GWL_STYLE, win32Style);

		// second time cleans up the rect after the border has been removed
		SetWindowPos(inHandle, HWND_TOP, 0, 0, width, height, flags);

		// note: double SetWindowPos call isn't very effective on slower machines anyway :/
	}
	ShowWindow(inHandle, SW_SHOW);
}

/******************************************************************************
 * Gets the screen scaling factor of the device from the supplied handle
 *****************************************************************************/
float WindowsPlatform::getScreenScalingFactor(const sf::WindowHandle& inHandle)
{
	UNUSED(inHandle);

	if (m_screenScalingFactor != 0.0f)
		return m_screenScalingFactor;

	HDC screenDC = GetDC(nullptr);
	int logicalScreenHeight = GetDeviceCaps(screenDC, VERTRES);
	int physicalScreenHeight = GetDeviceCaps(screenDC, DESKTOPVERTRES);
	m_screenScalingFactor = static_cast<float>(physicalScreenHeight) / static_cast<float>(logicalScreenHeight);
	ReleaseDC(nullptr, screenDC);

	return m_screenScalingFactor;
}

/******************************************************************************
 * Gets the refresh rate of the device from the supplied handle
 *****************************************************************************/
int WindowsPlatform::getRefreshRate(const sf::WindowHandle& inHandle)
{
	UNUSED(inHandle);

	if (m_refreshRate != 0)
		return m_refreshRate;

	HDC screenDC = GetDC(nullptr);
	m_refreshRate = GetDeviceCaps(screenDC, VREFRESH);
	ReleaseDC(nullptr, screenDC);

	return m_refreshRate;
}

/******************************************************************************
 * Loads a .ico file from The application's resources, and can contain multiple
 * sizes (for instance 16x16, 32x32 & 64x64). This is referred to as an
 * "Icon Directory". Additionally, it can have a single icon
 *****************************************************************************/
PBYTE WindowsPlatform::getIconDirectory(const int inResourceId)
{
	HMODULE hModule = GetModuleHandle(nullptr);
	HRSRC hResource = FindResource(hModule, MAKEINTRESOURCE(inResourceId), RT_GROUP_ICON);

	HGLOBAL hData = LoadResource(hModule, hResource);
	PBYTE data = (PBYTE)LockResource(hData);

	return data;
}

/******************************************************************************
 * This will attempt to load a single icon from an icon directory
 * If the requested size isn't found, the first one is returned
 *****************************************************************************/
HICON WindowsPlatform::getIconFromIconDirectory(PBYTE inIconDirectory, const uint inSize)
{
	HMODULE hModule = GetModuleHandle(nullptr);
	int resourceId = LookupIconIdFromDirectoryEx(inIconDirectory, TRUE, inSize, inSize, LR_DEFAULTCOLOR | LR_SHARED);
	HRSRC hResource = FindResource(hModule, MAKEINTRESOURCE(resourceId), RT_ICON);

	HGLOBAL hData = LoadResource(hModule, hResource);
	PBYTE data = (PBYTE)LockResource(hData);
	DWORD sizeofData = SizeofResource(hModule, hResource);

	HICON icon = CreateIconFromResourceEx(data, sizeofData, TRUE, 0x00030000, inSize, inSize, LR_DEFAULTCOLOR | LR_SHARED);
	return icon;
}

/******************************************************************************
 * Takes an SFML window style and matches it back to the Win32 equivalent
 *****************************************************************************/
DWORD WindowsPlatform::sfmlWindowStyleToWin32WindowStyle(const sf::Uint32 inStyle)
{
	DWORD style = 0;
	if (inStyle == sf::Style::None || inStyle == sf::Style::Fullscreen)
	{
		style = WS_VISIBLE | WS_POPUP | WS_CLIPCHILDREN | WS_CLIPSIBLINGS;
	}
	else
	{
		style = WS_VISIBLE;
		if (inStyle & sf::Style::Titlebar)
			style |= WS_CAPTION | WS_MINIMIZEBOX;
		if (inStyle & sf::Style::Resize)
			style |= WS_THICKFRAME | WS_MAXIMIZEBOX;
		if (inStyle & sf::Style::Close)
			style |= WS_SYSMENU;
	}

	return style;
}
}

#endif // _WIN32