From 51f0cd3b510b90237236dfc46a9afe61b8713925 Mon Sep 17 00:00:00 2001 From: Christopher Pelloux Date: Tue, 23 Feb 2016 23:40:22 -0500 Subject: [PATCH] Win32: Implement GLFW_TRANSPARENT This is a squashed extract of several commits, minimally edited to ensure it compiles. Related to #197. Related to #723. --- src/wgl_context.c | 102 +++++++++++++++++++++++++++++++++++++++++-- src/win32_init.c | 2 + src/win32_platform.h | 16 +++++++ 3 files changed, 117 insertions(+), 3 deletions(-) diff --git a/src/wgl_context.c b/src/wgl_context.c index 1f2b12a5..990eb299 100644 --- a/src/wgl_context.c +++ b/src/wgl_context.c @@ -83,6 +83,20 @@ static int choosePixelFormat(_GLFWwindow* window, { const int n = i + 1; _GLFWfbconfig* u = usableConfigs + usableCount; + PIXELFORMATDESCRIPTOR pfd; + + if (window->transparent) { + if (!DescribePixelFormat(window->context.wgl.dc, + n, + sizeof(PIXELFORMATDESCRIPTOR), + &pfd)) + { + continue; + } + + if (!(pfd.dwFlags & PFD_SUPPORT_COMPOSITION)) + continue; + } if (_glfw.wgl.ARB_pixel_format) { @@ -152,11 +166,9 @@ static int choosePixelFormat(_GLFWwindow* window, } else { - PIXELFORMATDESCRIPTOR pfd; - // Get pixel format attributes through legacy PFDs - if (!DescribePixelFormat(window->context.wgl.dc, + if (!window->transparent && DescribePixelFormat(window->context.wgl.dc, n, sizeof(PIXELFORMATDESCRIPTOR), &pfd)) @@ -203,6 +215,15 @@ static int choosePixelFormat(_GLFWwindow* window, u->handle = n; usableCount++; } + // Reiterate the selection loop without looking for transparency supporting + // formats if no matching pixelformat for a transparent window were found. + if (window->transparent && !usableCount) { + window->transparent = GLFW_FALSE; + free(usableConfigs); + _glfwInputError(GLFW_PLATFORM_ERROR, + "WGL: No pixel format found for transparent window. Ignoring transparency."); + return choosePixelFormat(window, ctxconfig, fbconfig); + } if (!usableCount) { @@ -484,6 +505,75 @@ void _glfwTerminateWGL(void) attribs[index++] = v; \ } +static GLFWbool setupTransparentWindow(_GLFWwindow* window) +{ + if (!isCompositionEnabled) { + _glfwInputError(GLFW_PLATFORM_ERROR, + "WGL: Composition needed for transparent window is disabled"); + } + if (!_glfw_DwmEnableBlurBehindWindow) { + _glfwInputError(GLFW_PLATFORM_ERROR, + "WGL: Unable to load DwmEnableBlurBehindWindow required for transparent window"); + return GLFW_FALSE; + } + + HRESULT hr = S_OK; + HWND handle = window->win32.handle; + + DWM_BLURBEHIND bb = { 0 }; + bb.dwFlags = DWM_BB_ENABLE | DWM_BB_BLURREGION; + bb.hRgnBlur = CreateRectRgn(0, 0, -1, -1); // makes the window transparent + bb.fEnable = TRUE; + hr = _glfw_DwmEnableBlurBehindWindow(handle, &bb); + + if (!SUCCEEDED(hr)) { + _glfwInputError(GLFW_PLATFORM_ERROR, + "WGL: Failed to enable blur behind window required for transparent window"); + return GLFW_FALSE; + } + + // Decorated windows on Windows 8+ don't repaint the transparent background + // leaving a trail behind animations. + // Hack: making the window layered with a transparency color key seems to fix this. + // Normally, when specifying a transparency color key to be used when composing + // the layered window, all pixels painted by the window in this color will be transparent. + // That doesn't seem to be the case anymore on Windows 8+, at least when used with + // DwmEnableBlurBehindWindow + negative region. + if (window->decorated && IsWindows8OrGreater()) + { + long style = GetWindowLong(handle, GWL_EXSTYLE); + if (!style) { + _glfwInputError(GLFW_PLATFORM_ERROR, + "WGL: Failed to retrieve extended styles. GetLastError: %d", + GetLastError()); + return GLFW_FALSE; + } + style |= WS_EX_LAYERED; + if (!SetWindowLongPtr(handle, GWL_EXSTYLE, style)) + { + _glfwInputError(GLFW_PLATFORM_ERROR, + "WGL: Failed to add layered style. GetLastError: %d", + GetLastError()); + return GLFW_FALSE; + } + if (!SetLayeredWindowAttributes(handle, + // Using a color key not equal to black to fix the trailing issue. + // When set to black, something is making the hit test not resize with the + // window frame. + RGB(0, 193, 48), + 255, + LWA_COLORKEY)) + { + _glfwInputError(GLFW_PLATFORM_ERROR, + "WGL: Failed to set layered window. GetLastError: %d", + GetLastError()); + return GLFW_FALSE; + } + } + + return GLFW_TRUE; +} + // Create the OpenGL or OpenGL ES context // GLFWbool _glfwCreateContextWGL(_GLFWwindow* window, @@ -713,6 +803,12 @@ GLFWbool _glfwCreateContextWGL(_GLFWwindow* window, } } + if (window->transparent) + { + if (!setupTransparentWindow(window)) + window->transparent = GLFW_FALSE; + } + window->context.makeCurrent = makeContextCurrentWGL; window->context.swapBuffers = swapBuffersWGL; window->context.swapInterval = swapIntervalWGL; diff --git a/src/win32_init.c b/src/win32_init.c index 7a8ee208..619fcfb1 100644 --- a/src/win32_init.c +++ b/src/win32_init.c @@ -131,6 +131,8 @@ static GLFWbool loadLibraries(void) GetProcAddress(_glfw.win32.dwmapi.instance, "DwmIsCompositionEnabled"); _glfw.win32.dwmapi.Flush = (PFN_DwmFlush) GetProcAddress(_glfw.win32.dwmapi.instance, "DwmFlush"); + _glfw.win32.dwmapi.DwmEnableBlurBehindWindow = (DWMENABLEBLURBEHINDWINDOW_T) + GetProcAddress(_glfw.win32.dwmapi.instance, "DwmEnableBlurBehindWindow"); } _glfw.win32.shcore.instance = LoadLibraryA("shcore.dll"); diff --git a/src/win32_platform.h b/src/win32_platform.h index e829799d..bfed5051 100644 --- a/src/win32_platform.h +++ b/src/win32_platform.h @@ -122,6 +122,19 @@ typedef enum PROCESS_DPI_AWARENESS } PROCESS_DPI_AWARENESS; #endif /*DPI_ENUMS_DECLARED*/ +#if !defined(_DWMAPI_H_) +#define DWM_BB_ENABLE 0x00000001 +#define DWM_BB_BLURREGION 0x00000002 + +typedef struct +{ + DWORD dwFlags; + BOOL fEnable; + HRGN hRgnBlur; + BOOL fTransitionOnMaximized; +} DWM_BLURBEHIND; +#endif + // HACK: Define versionhelpers.h functions manually as MinGW lacks the header FORCEINLINE BOOL IsWindowsVersionOrGreater(WORD major, WORD minor, WORD sp) { @@ -203,8 +216,10 @@ typedef BOOL (WINAPI * PFN_ChangeWindowMessageFilterEx)(HWND,UINT,DWORD,PCHANGEF // dwmapi.dll function pointer typedefs typedef HRESULT (WINAPI * PFN_DwmIsCompositionEnabled)(BOOL*); typedef HRESULT (WINAPI * PFN_DwmFlush)(VOID); +typedef HRESULT(WINAPI * DWMENABLEBLURBEHINDWINDOW_T)(HWND, const DWM_BLURBEHIND*); #define DwmIsCompositionEnabled _glfw.win32.dwmapi.IsCompositionEnabled #define DwmFlush _glfw.win32.dwmapi.Flush +#define _glfw_DwmEnableBlurBehindWindow _glfw.win32.dwmapi.DwmEnableBlurBehindWindow // shcore.dll function pointer typedefs typedef HRESULT (WINAPI * PFN_SetProcessDpiAwareness)(PROCESS_DPI_AWARENESS); @@ -310,6 +325,7 @@ typedef struct _GLFWlibraryWin32 HINSTANCE instance; PFN_DwmIsCompositionEnabled IsCompositionEnabled; PFN_DwmFlush Flush; + DWMENABLEBLURBEHINDWINDOW_T DwmEnableBlurBehindWindow; } dwmapi; struct {