Auto merge of #232 - jdm:egl_linux, r=glennw

Support EGL on non-Android Linux.

Rebase and squash of #220.

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Author: bors-servo

.travis.yml

@@ -7,6 +7,7 @@ addons:
     packages:
     - libxxf86vm-dev
     - libosmesa6-dev
+    - libgles2-mesa-dev
 before_install:
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo add-apt-repository -y ppa:ubuntu-toolchain-r/test; fi
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo apt-get update; fi

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 
 name = "layers"
-version = "0.2.3"
+version = "0.2.4"
 authors = ["The Servo Project Developers"]
 license = "MIT/Apache-2.0"
 
@@ -33,19 +33,23 @@ io-surface = "0.2.0"
 
 [target.i686-unknown-linux-gnu.dependencies]
 glx = "0.1.0"
+servo-egl = "0.2"
 x11 = { version = "2.3.0", features = ["xlib"] }
 
 [target.x86_64-unknown-linux-gnu.dependencies]
 glx = "0.1.0"
+servo-egl = "0.2"
 x11 = { version = "2.3.0", features = ["xlib"] }
 
 [target.arm-unknown-linux-gnueabihf.dependencies]
 glx = "0.1.0"
+servo-egl = "0.2"
 x11 = { version = "2.3.0", features = ["xlib"] }
 
 [target.aarch64-unknown-linux-gnu.dependencies]
 glx = "0.1.0"
+servo-egl = "0.2"
 x11 = { version = "2.3.0", features = ["xlib"] }
 
 [target.arm-linux-androideabi.dependencies]
-servo-egl = "0.2"
+servo-egl = "0.2"

src/lib.rs

@@ -40,7 +40,7 @@ extern crate x11;
 #[cfg(target_os="linux")]
 extern crate glx;
 
-#[cfg(target_os="android")]
+#[cfg(any(target_os = "linux", target_os = "android"))]
 extern crate egl;
 
 pub mod color;
@@ -65,10 +65,13 @@ pub mod platform {
     pub mod android {
         pub mod surface;
     }
+    #[cfg(any(target_os="android",target_os="linux"))]
+    pub mod egl {
+        pub mod surface;
+    }
     #[cfg(target_os="windows")]
     pub mod windows {
         pub mod surface;
     }
     pub mod surface;
 }
-

src/platform/egl/surface.rs

@@ -0,0 +1,136 @@
+// Copyright 2015 The Servo Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+//! Implementation of cross-process surfaces implementing  EGL surface.
+
+use texturegl::Texture;
+
+use egl::eglext::EGLImageKHR;
+use euclid::size::Size2D;
+use gleam::gl::{TEXTURE_2D, TexImage2D, UNSIGNED_BYTE};
+use skia::gl_context::GLContext;
+use skia::gl_rasterization_context::GLRasterizationContext;
+use std::iter::repeat;
+use std::os::raw::c_void;
+use std::sync::Arc;
+use std::vec::Vec;
+
+use gleam::gl;
+
+#[cfg(target_os = "linux")]
+const GL_FORMAT_BGRA: gl::GLuint = gl::BGRA;
+
+#[cfg(any(target_os = "android", target_os = "gonk"))]
+const GL_FORMAT_BGRA: gl::GLuint = gl::BGRA_EXT;
+
+#[cfg(target_os="linux")]
+pub use platform::linux::surface::NativeDisplay;
+
+#[cfg(target_os="android")]
+pub use platform::android::surface::NativeDisplay;
+
+pub struct EGLImageNativeSurface {
+    /// An EGLImage for the case of GPU rendering.
+    image: Option<EGLImageKHR>,
+
+    /// A heap-allocated bitmap for the case of CPU rendering.
+    bitmap: Option<Vec<u8>>,
+
+    /// Whether this pixmap will leak if the destructor runs. This is for debugging purposes.
+    will_leak: bool,
+
+    /// The size of this surface.
+    pub size: Size2D<i32>,
+}
+
+unsafe impl Send for EGLImageNativeSurface {}
+
+impl EGLImageNativeSurface {
+    pub fn new(_: &NativeDisplay, size: Size2D<i32>) -> EGLImageNativeSurface {
+        let len = size.width * size.height * 4;
+        let bitmap: Vec<u8> = repeat(0).take(len as usize).collect();
+
+        EGLImageNativeSurface {
+            image: None,
+            bitmap: Some(bitmap),
+            will_leak: true,
+            size: size,
+        }
+    }
+
+    /// This may only be called on the compositor side.
+    pub fn bind_to_texture(&self, _: &NativeDisplay, texture: &Texture) {
+        let _bound = texture.bind();
+        match self.image {
+            None => match self.bitmap {
+                Some(ref bitmap) => {
+                    let data = bitmap.as_ptr() as *const c_void;
+                    unsafe {
+                        TexImage2D(TEXTURE_2D,
+                                   0,
+                                   GL_FORMAT_BGRA as i32,
+                                   self.size.width as i32,
+                                   self.size.height as i32,
+                                   0,
+                                   GL_FORMAT_BGRA as u32,
+                                   UNSIGNED_BYTE,
+                                   data);
+                     }
+                }
+                None => {
+                    debug!("Cannot bind the buffer(CPU rendering), there is no bitmap");
+                }
+            },
+            Some(_image_khr) => {
+                panic!("TODO: Support GPU rasterizer path on EGL");
+            }
+        }
+    }
+
+    /// This may only be called on the painting side.
+    pub fn upload(&mut self, _: &NativeDisplay, data: &[u8]) {
+        match self.bitmap {
+            Some(ref mut bitmap) => {
+                bitmap.clear();
+                bitmap.extend_from_slice(data);
+            }
+            None => {
+                debug!("Cannot upload the buffer(CPU rendering), there is no bitmap");
+            }
+        }
+    }
+
+    pub fn get_id(&self) -> isize {
+        match self.image {
+            None => 0,
+            Some(image_khr) => image_khr as isize,
+        }
+    }
+
+    pub fn destroy(&mut self, _graphics_context: &NativeDisplay) {
+        if self.image.is_some() {
+            panic!("TODO: Support GPU rendering path on Android");
+        }
+        self.mark_wont_leak()
+    }
+
+    pub fn mark_will_leak(&mut self) {
+        self.will_leak = true
+    }
+
+    pub fn mark_wont_leak(&mut self) {
+        self.will_leak = false
+    }
+
+    pub fn gl_rasterization_context(&mut self,
+                                    _gl_context: Arc<GLContext>)
+                                    -> Option<GLRasterizationContext> {
+        panic!("TODO: Support GL context on EGL");
+    }
+}

src/platform/linux/surface.rs

@@ -11,6 +11,10 @@
 
 #![allow(non_snake_case)]
 
+//TODO: Linking EGL here is probably wrong - should it be done in gleam / glutin etc?
+#[link(name = "EGL")]
+extern {}
+
 use texturegl::Texture;
 
 use euclid::size::Size2D;
@@ -26,6 +30,8 @@ use std::str;
 use std::sync::Arc;
 use x11::xlib;
 
+use egl::egl::{EGLDisplay, GetCurrentDisplay};
+
 /// The display, visual info, and framebuffer configuration. This is needed in order to bind to a
 /// texture on the compositor side. This holds only a *weak* reference to the display and does not
 /// close it.
@@ -34,12 +40,25 @@ use x11::xlib;
 /// to fix because the Display is given to us by the native windowing system, but we should fix it
 /// someday.
 /// FIXME(pcwalton): Mark nonsendable.
+
 #[derive(Copy, Clone)]
-pub struct NativeDisplay {
+pub struct GLXDisplayInfo {
     pub display: *mut xlib::Display,
     visual_info: *mut xlib::XVisualInfo,
     framebuffer_configuration: Option<glx::types::GLXFBConfig>,
 }
+#[derive(Copy, Clone)]
+pub struct EGLDisplayInfo {
+    pub display: EGLDisplay,
+}
+
+#[derive(Copy, Clone)]
+pub enum NativeDisplay {
+    EGL(EGLDisplayInfo),
+    GLX(GLXDisplayInfo),
+}
+
+
 
 unsafe impl Send for NativeDisplay {}
 
@@ -50,11 +69,11 @@ impl NativeDisplay {
         let (compositor_visual_info, frambuffer_configuration) =
             NativeDisplay::compositor_visual_info(display);
 
-        NativeDisplay {
+        NativeDisplay::GLX(GLXDisplayInfo {
             display: display,
             visual_info: compositor_visual_info,
             framebuffer_configuration: frambuffer_configuration,
-        }
+        })
     }
 
     /// Chooses the compositor visual info using the same algorithm that the compositor uses.
@@ -141,11 +160,22 @@ impl NativeDisplay {
     }
 
     pub fn platform_display_data(&self) -> PlatformDisplayData {
-        PlatformDisplayData {
-            display: self.display,
-            visual_info: self.visual_info,
+        match *self {
+            NativeDisplay::GLX(info) => {
+                PlatformDisplayData {
+                    display: info.display,
+                    visual_info: info.visual_info,
+                }
+            }
+            NativeDisplay::EGL(_) => unreachable!(),
         }
     }
+
+    pub fn new_egl_display() -> NativeDisplay {
+        NativeDisplay::EGL(EGLDisplayInfo {
+            display: GetCurrentDisplay()
+        })
+    }
 }
 
 #[derive(RustcDecodable, RustcEncodable)]
@@ -170,7 +200,7 @@ impl Drop for PixmapNativeSurface {
 }
 
 impl PixmapNativeSurface {
-    pub fn new(display: &NativeDisplay, size: Size2D<i32>) -> PixmapNativeSurface {
+    pub fn new(display: &GLXDisplayInfo, size: Size2D<i32>) -> PixmapNativeSurface {
         unsafe {
             // Create the pixmap.
             let screen = xlib::XDefaultScreen(display.display);
@@ -197,6 +227,11 @@ impl PixmapNativeSurface {
         //
         // FIXME(pcwalton): RAII for exception safety?
         unsafe {
+            let display = match display {
+                &NativeDisplay::GLX(info) => info,
+                &NativeDisplay::EGL(_) => unreachable!(),
+            };
+
             let pixmap_attributes = [
                 glx::TEXTURE_TARGET_EXT as i32, glx::TEXTURE_2D_EXT as i32,
                 glx::TEXTURE_FORMAT_EXT as i32, glx::TEXTURE_FORMAT_RGBA_EXT as i32,
@@ -228,6 +263,11 @@ impl PixmapNativeSurface {
     /// This may only be called on the painting side.
     pub fn upload(&mut self, display: &NativeDisplay, data: &[u8]) {
         unsafe {
+            let display = match display {
+                &NativeDisplay::GLX(info) => info,
+                &NativeDisplay::EGL(_) => unreachable!(),
+            };
+
             let image = xlib::XCreateImage(display.display,
                                            (*display.visual_info).visual,
                                            32,
@@ -259,6 +299,11 @@ impl PixmapNativeSurface {
 
     pub fn destroy(&mut self, display: &NativeDisplay) {
         unsafe {
+            let display = match display {
+                &NativeDisplay::GLX(info) => info,
+                &NativeDisplay::EGL(_) => unreachable!(),
+            };
+
             assert!(self.pixmap != 0);
             xlib::XFreePixmap(display.display, self.pixmap);
             self.mark_wont_leak()