Auto merge of #602 - nical:more-units-api, r=glennw

Use strongly typed geometry - Part 2

Use strongly typed geometry in the public API. This changeset adds the LayoutPixel unit which is basically an alias to LayerPixel.
I think that it's best to keep the "Layer" terminology internal to webrender, and since the 1-1 correspondence between the api's layout pixels and internal layer pixels is somewhat coincidental, it will help to have separate names if things like async zoom introduce an actual difference between the two coordinate spaces (as it does in Gecko). Using an alias instead of a separate type comes from a mix of laziness (not having to cast from layout t layer pixels all over frame.rs) and the fact that currently layer and layout pixels are the same thing, but I'll add a separate unit if there is a preference for it.

I did not introduce ParentLayoutPixel. I don't know the API well enough yet to be sure whether some geometry is passed in a stacking context's parent coordinate space, but if so we should consider introducing a special unit for it, if only for the sake of proper documentation.

This PR is a lot easier to rebase than part 1 and is a breaking change to the public API, so it's fine to wait a bit if there are cross-crates changes that we want to coordinate before having to adapt servo to this (although it should be easy to do).

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Author: bors-servo

replay/src/main.rs

@@ -8,15 +8,14 @@ extern crate webrender_traits;
 
 use bincode::serde::deserialize;
 use byteorder::{LittleEndian, ReadBytesExt};
-use euclid::Size2D;
 use gleam::gl;
 use std::any::TypeId;
 use std::mem;
 use std::io::Read;
 use std::fs::File;
 use std::path::{Path, PathBuf};
 use std::env;
-use webrender_traits::{ApiMsg, RenderApi, PipelineId};
+use webrender_traits::{ApiMsg, RenderApi, PipelineId, LayerSize, DeviceUintSize};
 use webrender_traits::channel::PayloadHelperMethods;
 use glutin::{Event, ElementState, VirtualKeyCode as Key};
 
@@ -40,7 +39,7 @@ impl webrender_traits::RenderNotifier for Notifier {
 
     fn pipeline_size_changed(&mut self,
                              _pid: PipelineId,
-                             _size: Option<Size2D<f32>>) {
+                             _size: Option<LayerSize>) {
     }
 
     fn new_scroll_frame_ready(&mut self, _composite_needed: bool) {
@@ -145,7 +144,7 @@ fn main() {
                 println!("Rendering frame {}.", frame_num);
                 gl::clear(gl::COLOR_BUFFER_BIT);
                 renderer.update();
-                renderer.render(Size2D::new(width, height));
+                renderer.render(DeviceUintSize::new(width, height));
                 window.swap_buffers().unwrap();
             }
             Event::KeyboardInput(ElementState::Pressed, _, Some(Key::Right)) =>{

sample/src/main.rs

@@ -6,11 +6,11 @@ extern crate webrender_traits;
 extern crate euclid;
 
 use app_units::Au;
-use euclid::{Size2D, Point2D, Rect, Matrix4D};
 use gleam::gl;
 use std::path::PathBuf;
 use webrender_traits::{ColorF, Epoch, GlyphInstance};
 use webrender_traits::{ImageData, ImageFormat, PipelineId, RendererKind};
+use webrender_traits::{LayoutSize, LayoutPoint, LayoutRect, LayoutTransform, DeviceUintSize};
 use std::fs::File;
 use std::io::Read;
 use std::env;
@@ -45,7 +45,7 @@ impl webrender_traits::RenderNotifier for Notifier {
 
     fn pipeline_size_changed(&mut self,
                              _: PipelineId,
-                             _: Option<Size2D<f32>>) {
+                             _: Option<LayoutSize>) {
     }
 }
 
@@ -100,10 +100,10 @@ fn main() {
     let pipeline_id = PipelineId(0, 0);
     let mut builder = webrender_traits::DisplayListBuilder::new(pipeline_id);
 
-    let bounds = Rect::new(Point2D::new(0.0, 0.0), Size2D::new(width as f32, height as f32));
+    let bounds = LayoutRect::new(LayoutPoint::new(0.0, 0.0), LayoutSize::new(width as f32, height as f32));
     let clip_region = {
         let complex = webrender_traits::ComplexClipRegion::new(
-            Rect::new(Point2D::new(50.0, 50.0), Size2D::new(100.0, 100.0)),
+            LayoutRect::new(LayoutPoint::new(50.0, 50.0), LayoutSize::new(100.0, 100.0)),
             webrender_traits::BorderRadius::uniform(20.0));
 
         builder.new_clip_region(&bounds, vec![complex], None)
@@ -113,36 +113,36 @@ fn main() {
                                   bounds,
                                   clip_region,
                                   0,
-                                  &Matrix4D::identity(),
-                                  &Matrix4D::identity(),
+                                  &LayoutTransform::identity(),
+                                  &LayoutTransform::identity(),
                                   webrender_traits::MixBlendMode::Normal,
                                   Vec::new());
 
     let sub_clip = {
         let mask = webrender_traits::ImageMask {
             image: api.add_image(2, 2, None, ImageFormat::A8, ImageData::new(vec![0,80, 180, 255])),
-            rect: Rect::new(Point2D::new(75.0, 75.0), Size2D::new(100.0, 100.0)),
+            rect: LayoutRect::new(LayoutPoint::new(75.0, 75.0), LayoutSize::new(100.0, 100.0)),
             repeat: false,
         };
         let complex = webrender_traits::ComplexClipRegion::new(
-            Rect::new(Point2D::new(50.0, 50.0), Size2D::new(100.0, 100.0)),
+            LayoutRect::new(LayoutPoint::new(50.0, 50.0), LayoutSize::new(100.0, 100.0)),
             webrender_traits::BorderRadius::uniform(20.0));
 
         builder.new_clip_region(&bounds, vec![complex], Some(mask))
     };
 
-    builder.push_rect(Rect::new(Point2D::new(100.0, 100.0), Size2D::new(100.0, 100.0)),
+    builder.push_rect(LayoutRect::new(LayoutPoint::new(100.0, 100.0), LayoutSize::new(100.0, 100.0)),
                       sub_clip,
                       ColorF::new(0.0, 1.0, 0.0, 1.0));
-    builder.push_rect(Rect::new(Point2D::new(250.0, 100.0), Size2D::new(100.0, 100.0)),
+    builder.push_rect(LayoutRect::new(LayoutPoint::new(250.0, 100.0), LayoutSize::new(100.0, 100.0)),
                       sub_clip,
                       ColorF::new(0.0, 1.0, 0.0, 1.0));
 
     if false { // draw text?
         let font_bytes = load_file("res/FreeSans.ttf");
         let font_key = api.add_raw_font(font_bytes);
 
-        let text_bounds = Rect::new(Point2D::new(100.0, 200.0), Size2D::new(700.0, 300.0));
+        let text_bounds = LayoutRect::new(LayoutPoint::new(100.0, 200.0), LayoutSize::new(700.0, 300.0));
 
         let glyphs = vec![
             GlyphInstance {
@@ -221,15 +221,15 @@ fn main() {
     api.set_root_display_list(
         root_background_color,
         epoch,
-        Size2D::new(width as f32, height as f32),
+        LayoutSize::new(width as f32, height as f32),
         builder);
     api.set_root_pipeline(pipeline_id);
 
     for event in window.wait_events() {
         gl::clear(gl::COLOR_BUFFER_BIT);
         renderer.update();
 
-        renderer.render(Size2D::new(width, height));
+        renderer.render(DeviceUintSize::new(width, height));
 
         window.swap_buffers().ok();