Auto merge of #209 - vvuk:win32, r=mrobinson

Implement windows surface for rust-layers

Implement a windows surface, just using an in-memory buffer

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Author: bors-servo

.gitignore

@@ -1,3 +1,4 @@
 /doc
 /target
 /Cargo.lock
+*~

src/lib.rs

@@ -62,6 +62,10 @@ pub mod platform {
     pub mod android {
         pub mod surface;
     }
+    #[cfg(target_os="windows")]
+    pub mod windows {
+        pub mod surface;
+    }
     pub mod surface;
 }
 

src/platform/surface.rs

@@ -15,6 +15,7 @@ use texturegl::Texture;
 use euclid::size::Size2D;
 use skia::gl_rasterization_context::GLRasterizationContext;
 use skia::gl_context::GLContext;
+use skia::gl_context::PlatformDisplayData;
 use std::sync::Arc;
 
 #[cfg(not(target_os="android"))]
@@ -34,6 +35,9 @@ use std::ptr;
 pub use platform::android::surface::{NativeDisplay,
                                      EGLImageNativeSurface};
 
+#[cfg(target_os="windows")]
+pub use platform::windows::surface::NativeDisplay;
+
 pub enum NativeSurface {
     MemoryBuffer(MemoryBufferNativeSurface),
 #[cfg(target_os="linux")]
@@ -72,6 +76,14 @@ impl NativeSurface {
    }
 }
 
+#[cfg(target_os="windows")]
+impl NativeSurface {
+    /// Creates a new native surface with uninitialized data.
+    pub fn new(display: &NativeDisplay, size: Size2D<i32>) -> NativeSurface {
+        NativeSurface::MemoryBuffer(MemoryBufferNativeSurface::new(display, size))
+   }
+}
+
 macro_rules! native_surface_method_with_mutability {
     ($self_:ident, $function_name:ident, $surface:ident, $pattern:pat, $($argument:ident),*) => {
         match *$self_ {

src/platform/windows/surface.rs

@@ -0,0 +1,16 @@
+use skia::gl_context::PlatformDisplayData;
+
+#[derive(Copy, Clone)]
+pub struct NativeDisplay;
+
+#[cfg(target_os="windows")]
+impl NativeDisplay {
+    pub fn new() -> NativeDisplay {
+        NativeDisplay
+    }
+
+    pub fn platform_display_data(&self) -> PlatformDisplayData {
+        PlatformDisplayData::new()
+    }
+}
+

src/texturegl.rs

@@ -160,6 +160,11 @@ impl Texture {
         (Flip::NoFlip, TextureTarget::TextureTarget2D)
     }
 
+    #[cfg(target_os="windows")]
+    pub fn texture_flip_and_target(_: bool) -> (Flip, TextureTarget) {
+        (Flip::NoFlip, TextureTarget::TextureTarget2D)
+    }
+
     /// Returns the raw OpenGL texture underlying this texture.
     pub fn native_texture(&self) -> GLuint {
         self.id