From 8164e5ae6fa33c9ec2a14f107585a7cbe7fbf813 Mon Sep 17 00:00:00 2001
From: Kae <80987908+Novaenia@users.noreply.github.com>
Date: Thu, 14 Mar 2024 21:17:05 +1100
Subject: [PATCH] Game window respects Windows theme setting

---
 .../application/StarMainApplication_sdl.cpp   | 26 ++++++++++++++++++-
 source/rendering/StarWorldCamera.hpp          |  8 +++---
 2 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/source/application/StarMainApplication_sdl.cpp b/source/application/StarMainApplication_sdl.cpp
index 2130968..7b1601f 100644
--- a/source/application/StarMainApplication_sdl.cpp
+++ b/source/application/StarMainApplication_sdl.cpp
@@ -10,6 +10,11 @@
 #include "SDL2/SDL.h"
 #include "StarPlatformServices_pc.hpp"
 
+#ifdef STAR_SYSTEM_WINDOWS
+#include "SDL2/SDL_syswm.h"
+#include <dwmapi.h>
+#endif
+
 namespace Star {
 
 Maybe<Key> keyFromSdlKeyCode(SDL_Keycode sym) {
@@ -268,11 +273,30 @@ public:
     m_sdlWindow = SDL_CreateWindow(m_windowTitle.utf8Ptr(), SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
         m_windowSize[0], m_windowSize[1], SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE);
     if (!m_sdlWindow)
-      throw ApplicationException::format("Application: Could not create SDL window: {}", SDL_GetError());
+      throw ApplicationException::format("Application: Could not create SDL Window: {}", SDL_GetError());
 
     SDL_ShowWindow(m_sdlWindow);
     SDL_RaiseWindow(m_sdlWindow);
 
+// Makes the window border black. From https://github.com/libsdl-org/SDL/commit/89948787#diff-f2ae5c36a8afc0a9a343a6664ab306da2963213e180af8cd97b12397dcbb9ae7R1478
+#ifdef STAR_SYSTEM_WINDOWS
+    if (void* handle = SDL_LoadObject("dwmapi.dll")) {
+      if (auto DwmSetWindowAttributeFunc = (decltype(&DwmSetWindowAttribute))SDL_LoadFunction(handle, "DwmSetWindowAttribute")) {
+        SDL_SysWMinfo wmInfo{};
+        SDL_VERSION(&wmInfo.version);
+        SDL_GetWindowWMInfo(m_sdlWindow, &wmInfo);
+        DWORD type{}, value{}, count = sizeof(value);
+        LSTATUS status = RegGetValue(HKEY_CURRENT_USER,
+                             TEXT("Software\\Microsoft\\Windows\\CurrentVersion\\Themes\\Personalize"),
+                             TEXT("AppsUseLightTheme"),
+                             RRF_RT_REG_DWORD, &type, &value, &count);
+        BOOL enabled = status == ERROR_SUCCESS && type == REG_DWORD && value == 0;
+        DwmSetWindowAttributeFunc(wmInfo.info.win.window, DWMWA_USE_IMMERSIVE_DARK_MODE, &enabled, sizeof(enabled));
+      }
+      SDL_UnloadObject(handle);
+    }
+#endif
+
     int width;
     int height;
     SDL_GetWindowSize(m_sdlWindow, &width, &height);
diff --git a/source/rendering/StarWorldCamera.hpp b/source/rendering/StarWorldCamera.hpp
index d83a31a..e022560 100644
--- a/source/rendering/StarWorldCamera.hpp
+++ b/source/rendering/StarWorldCamera.hpp
@@ -88,15 +88,15 @@ inline Vec2F WorldCamera::centerWorldPosition() const {
 inline Vec2F WorldCamera::worldToScreen(Vec2F const& worldCoord) const {
   Vec2F wrappedCoord = m_worldGeometry.nearestTo(Vec2F(m_worldCenter), worldCoord);
   return Vec2F(
-      (wrappedCoord[0] - m_worldCenter[0]) * (TilePixels * m_pixelRatio) + m_screenSize[0] / 2.0,
-      (wrappedCoord[1] - m_worldCenter[1]) * (TilePixels * m_pixelRatio) + m_screenSize[1] / 2.0
+      (wrappedCoord[0] - m_worldCenter[0]) * (TilePixels * m_pixelRatio) + (float)m_screenSize[0] / 2.0,
+      (wrappedCoord[1] - m_worldCenter[1]) * (TilePixels * m_pixelRatio) + (float)m_screenSize[1] / 2.0
     );
 }
 
 inline Vec2F WorldCamera::screenToWorld(Vec2F const& screen) const {
   return Vec2F(
-      (screen[0] - m_screenSize[0] / 2.0) / (TilePixels * m_pixelRatio) + m_worldCenter[0],
-      (screen[1] - m_screenSize[1] / 2.0) / (TilePixels * m_pixelRatio) + m_worldCenter[1]
+      (screen[0] - (float)m_screenSize[0] / 2.0) / (TilePixels * m_pixelRatio) + m_worldCenter[0],
+      (screen[1] - (float)m_screenSize[1] / 2.0) / (TilePixels * m_pixelRatio) + m_worldCenter[1]
     );
 }