From 03ef34ffe83d25bbd54320c8cb2e535a256470a8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dar=C3=ADo?= <dariosamo@gmail.com>
Date: Sat, 22 Feb 2025 10:12:56 -0300
Subject: [PATCH] Dpi fixes (#449)

* Potential fix for DPI scaling.

* Show window size in pixels while in Fullscreen mode.
---
 UnleashedRecomp/gpu/rhi/plume_vulkan.cpp |  2 +-
 UnleashedRecomp/gpu/video.cpp            | 26 +++++++++++++++---------
 UnleashedRecomp/ui/game_window.cpp       |  5 +++++
 UnleashedRecomp/ui/game_window.h         |  1 +
 UnleashedRecomp/ui/options_menu.cpp      | 22 +++++++++++++-------
 5 files changed, 38 insertions(+), 18 deletions(-)

diff --git a/UnleashedRecomp/gpu/rhi/plume_vulkan.cpp b/UnleashedRecomp/gpu/rhi/plume_vulkan.cpp
index a181eab..477a431 100644
--- a/UnleashedRecomp/gpu/rhi/plume_vulkan.cpp
+++ b/UnleashedRecomp/gpu/rhi/plume_vulkan.cpp
@@ -2344,7 +2344,7 @@ namespace plume {
         dstWidth = rect.right - rect.left;
         dstHeight = rect.bottom - rect.top;
 #   elif defined(SDL_VULKAN_ENABLED)
-        SDL_GetWindowSize(renderWindow, (int *)(&dstWidth), (int *)(&dstHeight));
+        SDL_GetWindowSizeInPixels(renderWindow, (int *)(&dstWidth), (int *)(&dstHeight));
 #   elif defined(__ANDROID__)
         dstWidth = ANativeWindow_getWidth(renderWindow);
         dstHeight = ANativeWindow_getHeight(renderWindow);
diff --git a/UnleashedRecomp/gpu/video.cpp b/UnleashedRecomp/gpu/video.cpp
index f21f2ce..42f122c 100644
--- a/UnleashedRecomp/gpu/video.cpp
+++ b/UnleashedRecomp/gpu/video.cpp
@@ -2415,19 +2415,25 @@ static void DrawImGui()
     // we can adjust the mouse events before ImGui processes them.
     uint32_t width = g_swapChain->getWidth();
     uint32_t height = g_swapChain->getHeight();
-
-    if (width != Video::s_viewportWidth || height != Video::s_viewportHeight)
+    float mousePosScaleX = float(width) / float(GameWindow::s_width);
+    float mousePosScaleY = float(height) / float(GameWindow::s_height);
+    float mousePosOffsetX = (width - Video::s_viewportWidth) / 2.0f;
+    float mousePosOffsetY = (height - Video::s_viewportHeight) / 2.0f;
+    for (int i = 0; i < io.Ctx->InputEventsQueue.Size; i++)
     {
-        float mousePosOffsetX = (width - Video::s_viewportWidth) / 2.0f;
-        float mousePosOffsetY = (height - Video::s_viewportHeight) / 2.0f;
-
-        for (int i = 0; i < io.Ctx->InputEventsQueue.Size; i++)
+        auto& e = io.Ctx->InputEventsQueue[i];
+        if (e.Type == ImGuiInputEventType_MousePos)
         {
-            auto& e = io.Ctx->InputEventsQueue[i];
-            if (e.Type == ImGuiInputEventType_MousePos)
+            if (e.MousePos.PosX != -FLT_MAX)
             {
-                if (e.MousePos.PosX != -FLT_MAX) e.MousePos.PosX -= mousePosOffsetX;
-                if (e.MousePos.PosY != -FLT_MAX) e.MousePos.PosY -= mousePosOffsetY;
+                e.MousePos.PosX *= mousePosScaleX;
+                e.MousePos.PosX -= mousePosOffsetX;
+            }
+
+            if (e.MousePos.PosY != -FLT_MAX)
+            {
+                e.MousePos.PosY *= mousePosScaleY;
+                e.MousePos.PosY -= mousePosOffsetY;
             }
         }
     }
diff --git a/UnleashedRecomp/ui/game_window.cpp b/UnleashedRecomp/ui/game_window.cpp
index 3ed5fbb..cc25ab6 100644
--- a/UnleashedRecomp/ui/game_window.cpp
+++ b/UnleashedRecomp/ui/game_window.cpp
@@ -378,6 +378,11 @@ SDL_Rect GameWindow::GetDimensions()
     return rect;
 }
 
+void GameWindow::GetSizeInPixels(int *w, int *h)
+{
+    SDL_GetWindowSizeInPixels(s_pWindow, w, h);
+}
+
 void GameWindow::SetDimensions(int w, int h, int x, int y)
 {
     s_width = w;
diff --git a/UnleashedRecomp/ui/game_window.h b/UnleashedRecomp/ui/game_window.h
index 5f51b2f..bd0cb9a 100644
--- a/UnleashedRecomp/ui/game_window.h
+++ b/UnleashedRecomp/ui/game_window.h
@@ -37,6 +37,7 @@ public:
     static bool IsMaximised();
     static EWindowState SetMaximised(bool isEnabled);
     static SDL_Rect GetDimensions();
+    static void GetSizeInPixels(int *w, int *h);
     static void SetDimensions(int w, int h, int x = SDL_WINDOWPOS_CENTERED, int y = SDL_WINDOWPOS_CENTERED);
     static void ResetDimensions();
     static uint32_t GetWindowFlags();
diff --git a/UnleashedRecomp/ui/options_menu.cpp b/UnleashedRecomp/ui/options_menu.cpp
index b348d82..a16252d 100644
--- a/UnleashedRecomp/ui/options_menu.cpp
+++ b/UnleashedRecomp/ui/options_menu.cpp
@@ -1121,17 +1121,25 @@ static void DrawConfigOption(int32_t rowIndex, float yOffset, ConfigDef<T>* conf
     {
         if (config == &Config::WindowSize)
         {
-            auto displayModes = GameWindow::GetDisplayModes();
-
-            if (config->Value >= 0 && config->Value < displayModes.size())
+            if (Config::Fullscreen)
             {
-                auto& displayMode = displayModes[config->Value];
-
-                valueText = fmt::format("{}x{}", displayMode.w, displayMode.h);
+                int displayW, displayH;
+                GameWindow::GetSizeInPixels(&displayW, &displayH);
+                valueText = fmt::format("{}x{}", displayW, displayH);
             }
             else
             {
-                valueText = fmt::format("{}x{}", GameWindow::s_width, GameWindow::s_height);
+                auto displayModes = GameWindow::GetDisplayModes();
+                if (config->Value >= 0 && config->Value < displayModes.size())
+                {
+                    auto& displayMode = displayModes[config->Value];
+
+                    valueText = fmt::format("{}x{}", displayMode.w, displayMode.h);
+                }
+                else
+                {
+                    valueText = fmt::format("{}x{}", GameWindow::s_width, GameWindow::s_height);
+                }
             }
         }
         else if (config == &Config::Monitor)