From 4678a544b6f74753755c09291c63215bb37fc535 Mon Sep 17 00:00:00 2001 From: paddy <0xPD33@proton.me> Date: Tue, 17 Feb 2026 12:43:52 +0100 Subject: [PATCH] [rcore][glfw] Fix window scaling on Wayland with GLFW 3.4+ (#5564) * Fix window scaling on Wayland with GLFW 3.4+ display scaling GLFW 3.4 defaults GLFW_SCALE_FRAMEBUFFER to TRUE on all platforms, causing framebuffer/window size mismatch on Wayland with display scaling (content renders in a subset of the window, mouse coordinates are wrong). Three fixes: - Disable GLFW_SCALE_FRAMEBUFFER on Wayland when FLAG_WINDOW_HIGHDPI is not set, restoring 1:1 window-to-framebuffer mapping - With FLAG_WINDOW_HIGHDPI, read actual framebuffer size from GLFW instead of resizing the window (which double-scales on Wayland where GLFW_SCALE_TO_MONITOR has no effect) - Skip mouse coordinate scaling on Wayland since GLFW already reports coordinates in logical (window) space Tested on NixOS/Niri with GLFW 3.4 at 1x, 1.5x, and 2x scaling. Fixes #5504 * Fix fullscreen and borderless windowed scaling on Wayland with HiDPI ToggleFullscreen and ToggleBorderlessWindowed exit paths manually scale screen size by DPI before passing to glfwSetWindowMonitor, which double-scales on Wayland where GLFW_SCALE_FRAMEBUFFER already handles it. Skip the manual resize on Wayland. Also fix FramebufferSizeCallback fullscreen branch: on Wayland with GLFW_SCALE_FRAMEBUFFER the framebuffer is still scaled in fullscreen, so use the logical window size as screen size and derive screenScale from the framebuffer/window ratio. Fixes #5504 * Apply style fixes from code review: remove duplicate screenScale assignment, collapse single-statement ifs to one line, remove trailing periods from comments --- src/platforms/rcore_desktop_glfw.c | 56 +++++++++++++++++++++++------- 1 file changed, 43 insertions(+), 13 deletions(-) diff --git a/src/platforms/rcore_desktop_glfw.c b/src/platforms/rcore_desktop_glfw.c index 68a321ffd..4cb3726e1 100644 --- a/src/platforms/rcore_desktop_glfw.c +++ b/src/platforms/rcore_desktop_glfw.c @@ -221,7 +221,9 @@ void ToggleFullscreen(void) #if !defined(__APPLE__) // Make sure to restore render size considering HighDPI scaling - if (FLAG_IS_SET(CORE.Window.flags, FLAG_WINDOW_HIGHDPI)) + // NOTE: On Wayland, GLFW_SCALE_FRAMEBUFFER handles scaling, skip manual resize + if (FLAG_IS_SET(CORE.Window.flags, FLAG_WINDOW_HIGHDPI) && + (glfwGetPlatform() != GLFW_PLATFORM_WAYLAND)) { Vector2 scaleDpi = GetWindowScaleDPI(); CORE.Window.screen.width = (unsigned int)(CORE.Window.screen.width*scaleDpi.x); @@ -300,7 +302,9 @@ void ToggleBorderlessWindowed(void) #if !defined(__APPLE__) // Make sure to restore size considering HighDPI scaling - if (FLAG_IS_SET(CORE.Window.flags, FLAG_WINDOW_HIGHDPI)) + // NOTE: On Wayland, GLFW_SCALE_FRAMEBUFFER handles scaling, skip manual resize + if (FLAG_IS_SET(CORE.Window.flags, FLAG_WINDOW_HIGHDPI) && + (glfwGetPlatform() != GLFW_PLATFORM_WAYLAND)) { Vector2 scaleDpi = GetWindowScaleDPI(); CORE.Window.screen.width = (unsigned int)(CORE.Window.screen.width*scaleDpi.x); @@ -1465,6 +1469,8 @@ int InitPlatform(void) #if defined(__APPLE__) glfwWindowHint(GLFW_SCALE_FRAMEBUFFER, GLFW_FALSE); #endif + // GLFW 3.4+ defaults GLFW_SCALE_FRAMEBUFFER to TRUE, causing framebuffer/window size mismatch on Wayland with display scaling + if (glfwGetPlatform() == GLFW_PLATFORM_WAYLAND) glfwWindowHint(GLFW_SCALE_FRAMEBUFFER, GLFW_FALSE); } // Mouse passthrough @@ -1663,15 +1669,23 @@ int InitPlatform(void) // NOTE: On APPLE platforms system manage window and input scaling // Framebuffer scaling is activated with: glfwWindowHint(GLFW_SCALE_FRAMEBUFFER, GLFW_TRUE); - // Screen scaling matrix is required in case desired screen area is different from display area - CORE.Window.screenScale = MatrixScale(scaleDpi.x, scaleDpi.y, 1.0f); - #if !defined(__APPLE__) - // Mouse input scaling for the new screen size - SetMouseScale(1.0f/scaleDpi.x, 1.0f/scaleDpi.y); + if (glfwGetPlatform() == GLFW_PLATFORM_WAYLAND) + { + // On Wayland, GLFW_SCALE_FRAMEBUFFER handles scaling; read actual framebuffer size instead of resizing the window (which would double-scale) + int fbWidth, fbHeight; + glfwGetFramebufferSize(platform.handle, &fbWidth, &fbHeight); + CORE.Window.render.width = fbWidth; + CORE.Window.render.height = fbHeight; + } + else + { + // Mouse input scaling for the new screen size + SetMouseScale(1.0f/scaleDpi.x, 1.0f/scaleDpi.y); - // Force window size (and framebuffer) refresh - glfwSetWindowSize(platform.handle, CORE.Window.render.width, CORE.Window.render.height); + // Force window size (and framebuffer) refresh + glfwSetWindowSize(platform.handle, CORE.Window.render.width, CORE.Window.render.height); + } #endif } else CORE.Window.render = CORE.Window.screen; @@ -1855,6 +1869,22 @@ static void FramebufferSizeCallback(GLFWwindow *window, int width, int height) CORE.Window.screen.height = height; CORE.Window.screenScale = MatrixScale(1.0f, 1.0f, 1.0f); SetMouseScale(1.0f, 1.0f); + + // On Wayland with GLFW_SCALE_FRAMEBUFFER, the framebuffer is still scaled in fullscreen, use logical window size as screen and apply screenScale + if ((glfwGetPlatform() == GLFW_PLATFORM_WAYLAND) && + FLAG_IS_SET(CORE.Window.flags, FLAG_WINDOW_HIGHDPI)) + { + int winWidth, winHeight; + glfwGetWindowSize(platform.handle, &winWidth, &winHeight); + if ((winWidth != width) || (winHeight != height)) + { + CORE.Window.screen.width = winWidth; + CORE.Window.screen.height = winHeight; + float scaleX = (float)width/winWidth; + float scaleY = (float)height/winHeight; + CORE.Window.screenScale = MatrixScale(scaleX, scaleY, 1.0f); + } + } } else // Window mode (including borderless window) { @@ -1867,8 +1897,8 @@ static void FramebufferSizeCallback(GLFWwindow *window, int width, int height) CORE.Window.screen.height = (int)((float)height/scaleDpi.y); CORE.Window.screenScale = MatrixScale(scaleDpi.x, scaleDpi.y, 1.0f); #if !defined(__APPLE__) - // Mouse input scaling for the new screen size - SetMouseScale(1.0f/scaleDpi.x, 1.0f/scaleDpi.y); + // On Wayland, mouse coords are already in logical space + if (glfwGetPlatform() != GLFW_PLATFORM_WAYLAND) SetMouseScale(1.0f/scaleDpi.x, 1.0f/scaleDpi.y); #endif } else @@ -1897,8 +1927,8 @@ static void WindowContentScaleCallback(GLFWwindow *window, float scalex, float s CORE.Window.screenScale = MatrixScale(scalex, scaley, 1.0f); #if !defined(__APPLE__) - // Mouse input scaling for the new screen size - SetMouseScale(1.0f/scalex, 1.0f/scaley); + // On Wayland, mouse coords are already in logical space + if (glfwGetPlatform() != GLFW_PLATFORM_WAYLAND) SetMouseScale(1.0f/scalex, 1.0f/scaley); #endif }