servo: Merge #9781 - Allow user to choose between GL and ES2 (from jd…

…m:refactor_gle); r=glennw

Rebase of #8869. Requires servo/rust-layers#232.

Source-Repo: https://github.com/servo/servo
Source-Revision: f3a871ec3ded9efe5dfc07f8a3a39ddd6fb05856

UltraBlame original commit: a174eef4faed2e8280b7e4b5b896e56f6b270d07

servo/components/util/opts.rs

@@ -186,6 +186,9 @@ pub struct Opts {
 
 
     pub use_msaa: bool,
+
+
+    pub render_api: RenderApi,
 }
 
 fn print_usage(app: &str, opts: &Options) {
@@ -391,6 +394,14 @@ enum UserAgent {
     Gonk,
 }
 
+#[derive(Clone, Debug, Eq, Deserialize, PartialEq, Serialize)]
+pub enum RenderApi {
+    GL,
+    ES2,
+}
+
+const DEFAULT_RENDER_API: RenderApi = RenderApi::GL;
+
 fn default_user_agent_string(agent: UserAgent) -> String {
     #[cfg(all(target_os = "linux", target_arch = "x86_64"))]
     const DESKTOP_UA_STRING: &'static str =
@@ -487,6 +498,7 @@ pub fn default_opts() -> Opts {
         use_webrender: false,
         webrender_stats: false,
         use_msaa: false,
+        render_api: DEFAULT_RENDER_API,
     }
 }
 
@@ -531,6 +543,7 @@ pub fn from_cmdline_args(args: &[String]) -> ArgumentParsingResult {
                   "A preference to set to enable", "dom.mozbrowser.enabled");
     opts.optflag("b", "no-native-titlebar", "Do not use native titlebar");
     opts.optflag("w", "webrender", "Use webrender backend");
+    opts.optopt("G", "graphics", "Select graphics backend (gl or es2)", "gl");
 
     let opt_match = match opts.parse(args) {
         Ok(m) => m,
@@ -675,6 +688,13 @@ pub fn from_cmdline_args(args: &[String]) -> ArgumentParsingResult {
 
     let use_webrender = opt_match.opt_present("w") && !opt_match.opt_present("z");
 
+    let render_api = match opt_match.opt_str("G") {
+        Some(ref ga) if ga == "gl" => RenderApi::GL,
+        Some(ref ga) if ga == "es2" => RenderApi::ES2,
+        None => DEFAULT_RENDER_API,
+        _ => args_fail(&format!("error: graphics option must be gl or es2:")),
+    };
+
     let opts = Opts {
         is_running_problem_test: is_running_problem_test,
         url: Some(url),
@@ -704,6 +724,7 @@ pub fn from_cmdline_args(args: &[String]) -> ArgumentParsingResult {
         user_agent: user_agent,
         multiprocess: opt_match.opt_present("M"),
         sandbox: opt_match.opt_present("S"),
+        render_api: render_api,
         show_debug_borders: debug_options.show_compositor_borders,
         show_debug_fragment_borders: debug_options.show_fragment_borders,
         show_debug_parallel_paint: debug_options.show_parallel_paint,

servo/ports/glutin/window.rs

@@ -33,7 +33,7 @@ use style_traits::cursor::Cursor;
 use url::Url;
 use util::geometry::ScreenPx;
 #[cfg(feature = "window")]
-use util::opts;
+use util::opts::{self, RenderApi};
 
 #[cfg(feature = "window")]
 static mut g_nested_event_loop_listener: Option<*mut (NestedEventLoopListener + 'static)> = None;
@@ -157,9 +157,15 @@ impl Window {
     #[cfg(not(target_os = "android"))]
     fn gl_version() -> GlRequest {
         if opts::get().use_webrender {
-            GlRequest::Specific(Api::OpenGl, (3, 2))
-        } else {
-            GlRequest::Specific(Api::OpenGl, (2, 1))
+            return GlRequest::Specific(Api::OpenGl, (3, 2));
+        }
+        match opts::get().render_api {
+            RenderApi::GL => {
+                GlRequest::Specific(Api::OpenGl, (2, 1))
+            }
+            RenderApi::ES2 => {
+                GlRequest::Specific(Api::OpenGlEs, (2, 0))
+            }
         }
     }
 
@@ -672,7 +678,14 @@ impl WindowMethods for Window {
     fn native_display(&self) -> NativeDisplay {
         use x11::xlib;
         unsafe {
-            NativeDisplay::new(self.window.platform_display() as *mut xlib::Display)
+            match opts::get().render_api {
+                RenderApi::GL => {
+                    NativeDisplay::new(self.window.platform_display() as *mut xlib::Display)
+                },
+                RenderApi::ES2 => {
+                    NativeDisplay::new_egl_display()
+                }
+            }
         }
     }