some updates

4J.Render/4J_Render.cpp

@@ -15,8 +15,11 @@ C4JRender RenderManager;
 
 static GLFWwindow *s_window = nullptr;
 static int s_textureLevels = 1;
-static int s_windowWidth = 1920;
-static int s_windowHeight = 1080;
+static int s_windowWidth  = 1280;  // updated to actual framebuffer size each frame
+static int s_windowHeight = 720;
+static int s_reqWidth     = 0;     // 0 = auto-detect from primary monitor
+static int s_reqHeight    = 0;
+static bool s_fullscreen  = false;
 
 // Thread-local storage for per-thread shared GL contexts.
 // The main thread uses s_window directly; worker threads get invisible
@@ -54,12 +57,29 @@ void C4JRender::Initialise()
         return;
     }
 
+    // Resolve window dimensions: use caller-requested size, or fall back to
+    // the primary monitor's native resolution so the window fits any display.
+    GLFWmonitor *primaryMonitor = glfwGetPrimaryMonitor();
+    const GLFWvidmode *mode = primaryMonitor ? glfwGetVideoMode(primaryMonitor) : nullptr;
+
+    if (s_reqWidth > 0 && s_reqHeight > 0) {
+        s_windowWidth  = s_reqWidth;
+        s_windowHeight = s_reqHeight;
+    } else if (mode) {
+        s_windowWidth  = mode->width;
+        s_windowHeight = mode->height;
+    }
+    fprintf(stderr, "[4J_Render] Window %dx%d  fullscreen=%s\n",
+            s_windowWidth, s_windowHeight, s_fullscreen ? "yes" : "no");
+    fflush(stderr);
+
     // opengl 2.1!!!
     glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 2);
     glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 1);
 
+    GLFWmonitor *fsMonitor = s_fullscreen ? primaryMonitor : nullptr;
     s_window = glfwCreateWindow(s_windowWidth, s_windowHeight,
-                                "Minecraft Console Edition", nullptr, nullptr);
+                                "Minecraft Console Edition", fsMonitor, nullptr);
     if (!s_window) {
         fprintf(stderr, "[4J_Render] Failed to create GLFW window\n");
         glfwTerminate();
@@ -171,6 +191,17 @@ void C4JRender::Present()
     glfwPollEvents();
 }
 
+void C4JRender::SetWindowSize(int w, int h)
+{
+    s_reqWidth  = (w > 0) ? w : 0;
+    s_reqHeight = (h > 0) ? h : 0;
+}
+
+void C4JRender::SetFullscreen(bool fs)
+{
+    s_fullscreen = fs;
+}
+
 bool C4JRender::ShouldClose()
 {
     return !s_window || glfwWindowShouldClose(s_window);

4J.Render/4J_Render.h

@@ -63,6 +63,10 @@ public:
 	// Core
 	void Initialise();
 	void InitialiseContext();
+	// Call before Initialise() to override window size and/or fullscreen mode.
+	// If not called, the primary monitor's native resolution is used.
+	void SetWindowSize(int w, int h);
+	void SetFullscreen(bool fs);
 	void StartFrame();
 	void DoScreenGrabOnNextPresent();
 	void Present();

Minecraft.Client/Platform/Linux/Linux_Minecraft.cpp

@@ -587,6 +587,28 @@ int main(int argc, const char *argv[] )
 #endif
     app.DebugPrintf("---main()\n");
 
+    // ---- Parse CLI arguments ----
+    // Usage: Minecraft.Client [--width W] [--height H] [--fullscreen]
+    // If --width/--height are omitted the primary monitor's native resolution
+    // is used automatically.
+    {
+        int reqW = 0, reqH = 0;
+        bool fs = false;
+        for (int i = 1; i < argc; i++) {
+            if (strcmp(argv[i], "--fullscreen") == 0) {
+                fs = true;
+            } else if (strcmp(argv[i], "--width") == 0 && i + 1 < argc) {
+                reqW = atoi(argv[++i]);
+            } else if (strcmp(argv[i], "--height") == 0 && i + 1 < argc) {
+                reqH = atoi(argv[++i]);
+            }
+        }
+        if (reqW > 0 && reqH > 0)
+            RenderManager.SetWindowSize(reqW, reqH);
+        if (fs)
+            RenderManager.SetFullscreen(true);
+    }
+
     #if 0
     // Main message loop
     MSG msg = {0};
@@ -647,8 +669,15 @@ app.DebugPrintf("---ReadProductCodes()\n");
 
 app.loadMediaArchive();
 app.loadStringTable();
-ui.init(1920,1080);
-
+    // Use the actual framebuffer dimensions so the UI scales to whatever
+    // window/fullscreen resolution was chosen at startup.
+    {
+        int uiW = 1920, uiH = 1080;
+        RenderManager.GetFramebufferSize(uiW, uiH);
+        if (uiW < 1) uiW = 1920;
+        if (uiH < 1) uiH = 1080;
+        ui.init(uiW, uiH);
+    }
 // storage manager is needed for the trial key check
 StorageManager.Init(0,app.GetString(IDS_DEFAULT_SAVENAME),"savegame.dat",FIFTY_ONE_MB,&CConsoleMinecraftApp::DisplaySavingMessage,(LPVOID)&app,"");
 

README.md

@@ -11,9 +11,73 @@ Join our community:
 * Steam: https://steamcommunity.com/groups/4JCraft
 
 ## Planned platforms to be supported:
-- Linux (~95%)
+- Linux (~85%)
 - Emscripten (not started)
 - PS3
 - macOS (not started)
 - iOS (not started)
 - Android (not started)
+---
+
+## Building (Linux)
+
+### Dependencies
+
+Install the following packages before building (Debian/Ubuntu names shown):
+
+```bash
+sudo apt install \
+  build-essential cmake \
+  libglfw3-dev libgl-dev libglu1-mesa-dev \
+  libopenal-dev libvorbis-dev \
+  libpthread-stubs0-dev
+```
+
+On Arch/Manjaro:
+
+```bash
+sudo pacman -S base-devel gcc pkgconf cmake glfw-x11 mesa openal libvorbis glu
+```
+
+If you are on wayland, swap glfw-x11 to glfw-wayland, but its doesn't matter cuz xwayland got yourself covered
+
+### Configure & Build
+
+```bash
+# 1. Configure (only needed once, or after CMakeLists changes)
+cmake .
+
+# 2. Build (use -jN with your core count)
+make -j$(nproc)
+```
+
+The binary is output to:
+
+```
+Linux/Debug/Minecraft.Client
+```
+
+### Clean
+
+```bash
+make clean
+```
+
+To fully reset the CMake configuration (removes cache + generated Makefiles):
+
+```bash
+rm -rf CMakeCache.txt CMakeFiles cmake_install.cmake Makefile
+# Then re-run: cmake . && make -j$(nproc)
+```
+
+---
+
+## Running
+
+```bash
+# Default — window opens at your primary monitor's native resolution (windowed)
+./Linux/Debug/Minecraft.Client
+
+```
+
+(todo refactor)