From 1a956208e248971ca4acb75fbec4b2b485ee614e Mon Sep 17 00:00:00 2001
From: MasterZean <zean.z2legacy@gmail.com>
Date: Wed, 11 Sep 2019 16:39:40 +0300
Subject: [PATCH] fixes for switching full-screen and v-sync

---
 src/core.c | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/src/core.c b/src/core.c
index fad2c485f..553a6a9e2 100644
--- a/src/core.c
+++ b/src/core.c
@@ -311,6 +311,7 @@ static unsigned int displayWidth, displayHeight;// Display width and height (mon
 static int screenWidth, screenHeight;           // Screen width and height (used render area)
 static int renderWidth, renderHeight;           // Framebuffer width and height (render area, including black bars if required)
 static int currentWidth, currentHeight;         // Current render width and height, it could change on BeginTextureMode()
+static int windowLeftPos, windowTopPos;
 static int renderOffsetX = 0;                   // Offset X from render area (must be divided by 2)
 static int renderOffsetY = 0;                   // Offset Y from render area (must be divided by 2)
 static bool fullscreen = false;                 // Fullscreen mode (useful only for PLATFORM_DESKTOP)
@@ -853,8 +854,21 @@ void ToggleFullscreen(void)
     fullscreen = !fullscreen;          // Toggle fullscreen flag
 
     // NOTE: glfwSetWindowMonitor() doesn't work properly (bugs)
-    if (fullscreen) glfwSetWindowMonitor(window, glfwGetPrimaryMonitor(), 0, 0, screenWidth, screenHeight, GLFW_DONT_CARE);
-    else glfwSetWindowMonitor(window, NULL, 0, 0, screenWidth, screenHeight, GLFW_DONT_CARE);
+    if (fullscreen) {
+        glfwGetWindowPos(window, &windowLeftPos, &windowTopPos);
+
+        GLFWmonitor *monitor = glfwGetPrimaryMonitor();
+        if (!monitor)
+        {
+            TraceLog(LOG_WARNING, "Failed to get monitor");
+            glfwSetWindowMonitor(window, glfwGetPrimaryMonitor(), 0, 0, screenWidth, screenHeight, GLFW_DONT_CARE);
+            return;
+        }
+
+        const GLFWvidmode *mode = glfwGetVideoMode(monitor);
+        glfwSetWindowMonitor(window, glfwGetPrimaryMonitor(), 0, 0, screenWidth, screenHeight, mode->refreshRate);
+    }
+    else glfwSetWindowMonitor(window, NULL, windowLeftPos, windowTopPos, screenWidth, screenHeight, GLFW_DONT_CARE);
 #endif
 
 #if defined(PLATFORM_ANDROID) || defined(PLATFORM_RPI)
@@ -2672,6 +2686,13 @@ static bool InitGraphicsDevice(int width, int height)
 
     if (fullscreen)
     {
+        // remember center for switchinging from fullscreen to window
+        windowLeftPos = displayWidth/2 - screenWidth/2;
+        windowTopPos = displayHeight/2 - screenHeight/2;
+
+        if (windowLeftPos < 0) windowLeftPos = 0;
+        if (windowTopPos < 0) windowTopPos = 0;
+
         // Obtain recommended displayWidth/displayHeight from a valid videomode for the monitor
         int count = 0;
         const GLFWvidmode *modes = glfwGetVideoModes(glfwGetPrimaryMonitor(), &count);
@@ -3768,6 +3789,7 @@ static void PollInputEvents(void)
 static void SwapBuffers(void)
 {
 #if defined(PLATFORM_DESKTOP) || defined(PLATFORM_WEB)
+    glfwSwapInterval((configFlags & FLAG_VSYNC_HINT) != 0 ? 1 : 0);
     glfwSwapBuffers(window);
 #endif