Now using glXChooseFBConfig

src/x11/ffi.rs

@@ -13,7 +13,7 @@ pub type Drawable = XID;    // TODO: not sure
 pub type GLXContext = *const ();
 pub type GLXContextID = XID;
 pub type GLXDrawable = XID;
-pub type GLXFBConfig = ();
+pub type GLXFBConfig = *const ();
 pub type GLXPbuffer = XID;
 pub type GLXPixmap = XID;
 pub type GLXWindow = XID;
@@ -1348,6 +1348,7 @@ extern "C" {
     pub fn XDestroyWindow(display: *mut Display, w: Window);
     pub fn XFilterEvent(event: *mut XEvent, w: Window) -> Bool;
     pub fn XFlush(display: *mut Display);
+    pub fn XFree(data: *const libc::c_void);
     pub fn XGetGeometry(display: *mut Display, d: Drawable, root_return: *mut Window,
         x_return: *mut libc::c_int, y_return: *mut libc::c_int,
         width_return: *mut libc::c_uint, height_return: *mut libc::c_uint,
@@ -1386,10 +1387,11 @@ extern "C" {
         shareList: GLXContext, direct: Bool) -> GLXContext;
     pub fn glXDestroyContext(dpy: *mut Display, ctx: GLXContext);
     pub fn glXChooseFBConfig(dpy: *mut Display, screen: libc::c_int,
-        attrib_list: *const libc::c_int, nelements: *mut libc::c_int);
+        attrib_list: *const libc::c_int, nelements: *mut libc::c_int) -> *mut GLXFBConfig;
     pub fn glXChooseVisual(dpy: *mut Display, screen: libc::c_int,
         attribList: *const libc::c_int) -> *const XVisualInfo;
     pub fn glXGetProcAddress(procName: *const libc::c_uchar) -> *const ();
+    pub fn glXGetVisualFromFBConfig(dpy: *mut Display, config: GLXFBConfig) -> *mut XVisualInfo;
     pub fn glXMakeCurrent(dpy: *mut Display, drawable: GLXDrawable,
         ctx: GLXContext) -> Bool;
     pub fn glXSwapBuffers(dpy: *mut Display, drawable: GLXDrawable);
@@ -1398,7 +1400,6 @@ extern "C" {
 /*
 GLXFBConfig *glXGetFBConfigs (Display *dpy, int screen, int *nelements);
 int glXGetFBConfigAttrib (Display *dpy, GLXFBConfig config, int attribute, int *value);
-XVisualInfo *glXGetVisualFromFBConfig (Display *dpy, GLXFBConfig config);
 GLXWindow glXCreateWindow (Display *dpy, GLXFBConfig config, Window win, const int *attrib_list);
 void glXDestroyWindow (Display *dpy, GLXWindow win);
 GLXPixmap glXCreatePixmap (Display *dpy, GLXFBConfig config, Pixmap pixmap, const int *attrib_list);

src/x11/mod.rs

@@ -51,23 +51,46 @@ impl Window {
             display
         };
 
-        // TODO: set error handler
+        // TODO: set error handler?
 
-        static VISUAL_ATTRIBUTES: [libc::c_int, ..5] = [
+        // getting the FBConfig
-            ffi::GLX_RGBA,
+        let fb_config = unsafe {
-            ffi::GLX_DEPTH_SIZE,
+            static VISUAL_ATTRIBUTES: [libc::c_int, ..23] = [
-            24,
+                ffi::GLX_X_RENDERABLE,  1,
-            ffi::GLX_DOUBLEBUFFER,
+                ffi::GLX_DRAWABLE_TYPE, ffi::GLX_WINDOW_BIT,
-            0
+                ffi::GLX_RENDER_TYPE,   ffi::GLX_RGBA_BIT,
-        ];
+                ffi::GLX_X_VISUAL_TYPE, ffi::GLX_TRUE_COLOR,
+                ffi::GLX_RED_SIZE,      8,
+                ffi::GLX_GREEN_SIZE,    8,
+                ffi::GLX_BLUE_SIZE,     8,
+                ffi::GLX_ALPHA_SIZE,    8,
+                ffi::GLX_DEPTH_SIZE,    24,
+                ffi::GLX_STENCIL_SIZE,  8,
+                ffi::GLX_DOUBLEBUFFER,  1,
+                0
+            ];
+
+            let mut num_fb: libc::c_int = mem::uninitialized();
+
+            let fb = ffi::glXChooseFBConfig(display, ffi::XDefaultScreen(display),
+                VISUAL_ATTRIBUTES.as_ptr(), &mut num_fb);
+            if fb.is_null() {
+                return Err(format!("glXChooseFBConfig failed"));
+            }
+            let preferred_fb = *fb;     // TODO: choose more wisely
+            ffi::XFree(fb as *const libc::c_void);
+            preferred_fb
+        };
 
         // getting the visual infos
         let visual_infos = unsafe {
-            let vi = ffi::glXChooseVisual(display, 0, VISUAL_ATTRIBUTES.as_ptr());
+            let vi = ffi::glXGetVisualFromFBConfig(display, fb_config);
             if vi.is_null() {
                 return Err(format!("glXChooseVisual failed"));
             }
-            vi
+            let vi_copy = *vi;
+            ffi::XFree(vi as *const libc::c_void);
+            vi_copy
         };
 
         // getting the root window
@@ -76,7 +99,7 @@ impl Window {
         // creating the color map
         let cmap = unsafe {
             let cmap = ffi::XCreateColormap(display, root,
-                (*visual_infos).visual, ffi::AllocNone);
+                visual_infos.visual, ffi::AllocNone);
             // TODO: error checking?
             cmap
         };
@@ -97,8 +120,8 @@ impl Window {
             let dimensions = dimensions.unwrap_or((800, 600));
 
             let win = ffi::XCreateWindow(display, root, 50, 50, dimensions.val0() as libc::c_uint,
-                dimensions.val1() as libc::c_uint, 0, (*visual_infos).depth, ffi::InputOutput,
+                dimensions.val1() as libc::c_uint, 0, visual_infos.depth, ffi::InputOutput,
-                (*visual_infos).visual, ffi::CWColormap | ffi::CWEventMask,
+                visual_infos.visual, ffi::CWColormap | ffi::CWEventMask,
                 &mut set_win_attr);
             win
         };
@@ -142,7 +165,7 @@ impl Window {
 
         // creating GL context
         let context = unsafe {
-            ffi::glXCreateContext(display, visual_infos, ptr::null(), 1)
+            ffi::glXCreateContext(display, &visual_infos, ptr::null(), 1)
         };
 
         // returning