servo/components/gfx/paint_task.rs
Patrick Walton 1d845ee4f2 gfx: Update Azure and Skia, and rewrite broken clipping logic.
This exposed some problems in our clipping logic, which was never
properly rewritten for the stacking context reform. The clipping code
worked in terms of a stack of clips, but the new stacking context code
has no concept of a stack of clip regions. Fixing that in turn exposed
some flaky/incorrect tests:

* `borders` had an incorrect reference image, as far as I can tell.

* `negative_margins` had some stray pixels, fixed by changing the text.
2014-12-08 13:45:51 -08:00

590 lines
23 KiB
Rust

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
//! The task that handles all painting.
use buffer_map::BufferMap;
use display_list::{mod, StackingContext};
use font_cache_task::FontCacheTask;
use font_context::FontContext;
use paint_context::PaintContext;
use azure::azure_hl::{B8G8R8A8, Color, DrawTarget, SkiaBackend, StolenGLResources};
use azure::AzFloat;
use geom::matrix2d::Matrix2D;
use geom::point::Point2D;
use geom::rect::Rect;
use geom::size::Size2D;
use layers::platform::surface::{NativeGraphicsMetadata, NativePaintingGraphicsContext};
use layers::platform::surface::{NativeSurface, NativeSurfaceMethods};
use layers::layers::{BufferRequest, LayerBuffer, LayerBufferSet};
use layers;
use native::task::NativeTaskBuilder;
use servo_msg::compositor_msg::{Epoch, IdlePaintState, LayerId};
use servo_msg::compositor_msg::{LayerMetadata, PaintListener, PaintingPaintState, ScrollPolicy};
use servo_msg::constellation_msg::{ConstellationChan, Failure, FailureMsg, PipelineId};
use servo_msg::constellation_msg::{PainterReadyMsg};
use servo_msg::platform::surface::NativeSurfaceAzureMethods;
use servo_util::geometry::{Au, ZERO_POINT};
use servo_util::opts;
use servo_util::smallvec::SmallVec;
use servo_util::task::spawn_named_with_send_on_failure;
use servo_util::task_state;
use servo_util::time::{TimeProfilerChan, profile};
use servo_util::time;
use std::comm::{Receiver, Sender, channel};
use std::mem;
use std::task::TaskBuilder;
use sync::Arc;
/// Information about a hardware graphics layer that layout sends to the painting task.
#[deriving(Clone)]
pub struct PaintLayer {
/// A per-pipeline ID describing this layer that should be stable across reflows.
pub id: LayerId,
/// The color of the background in this layer. Used for unpainted content.
pub background_color: Color,
/// The scrolling policy of this layer.
pub scroll_policy: ScrollPolicy,
}
impl PaintLayer {
/// Creates a new `PaintLayer`.
pub fn new(id: LayerId, background_color: Color, scroll_policy: ScrollPolicy) -> PaintLayer {
PaintLayer {
id: id,
background_color: background_color,
scroll_policy: scroll_policy,
}
}
}
pub struct PaintRequest {
pub buffer_requests: Vec<BufferRequest>,
pub scale: f32,
pub layer_id: LayerId,
pub epoch: Epoch,
}
pub enum Msg {
PaintInitMsg(Arc<StackingContext>),
PaintMsg(Vec<PaintRequest>),
UnusedBufferMsg(Vec<Box<LayerBuffer>>),
PaintPermissionGranted,
PaintPermissionRevoked,
ExitMsg(Option<Sender<()>>),
}
#[deriving(Clone)]
pub struct PaintChan(Sender<Msg>);
impl PaintChan {
pub fn new() -> (Receiver<Msg>, PaintChan) {
let (chan, port) = channel();
(port, PaintChan(chan))
}
pub fn send(&self, msg: Msg) {
let &PaintChan(ref chan) = self;
assert!(chan.send_opt(msg).is_ok(), "PaintChan.send: paint port closed")
}
pub fn send_opt(&self, msg: Msg) -> Result<(), Msg> {
let &PaintChan(ref chan) = self;
chan.send_opt(msg)
}
}
pub struct PaintTask<C> {
id: PipelineId,
port: Receiver<Msg>,
compositor: C,
constellation_chan: ConstellationChan,
/// A channel to the time profiler.
time_profiler_chan: TimeProfilerChan,
/// The native graphics context.
native_graphics_context: Option<NativePaintingGraphicsContext>,
/// The root stacking context sent to us by the layout thread.
root_stacking_context: Option<Arc<StackingContext>>,
/// Permission to send paint messages to the compositor
paint_permission: bool,
/// A counter for epoch messages
epoch: Epoch,
/// A data structure to store unused LayerBuffers
buffer_map: BufferMap,
/// Communication handles to each of the worker threads.
worker_threads: Vec<WorkerThreadProxy>,
}
// If we implement this as a function, we get borrowck errors from borrowing
// the whole PaintTask struct.
macro_rules! native_graphics_context(
($task:expr) => (
$task.native_graphics_context.as_ref().expect("Need a graphics context to do painting")
)
)
fn initialize_layers<C>(compositor: &mut C,
pipeline_id: PipelineId,
epoch: Epoch,
root_stacking_context: &StackingContext)
where C: PaintListener {
let mut metadata = Vec::new();
build(&mut metadata, root_stacking_context, &ZERO_POINT);
compositor.initialize_layers_for_pipeline(pipeline_id, metadata, epoch);
fn build(metadata: &mut Vec<LayerMetadata>,
stacking_context: &StackingContext,
page_position: &Point2D<Au>) {
let page_position = stacking_context.bounds.origin + *page_position;
match stacking_context.layer {
None => {}
Some(ref paint_layer) => {
metadata.push(LayerMetadata {
id: paint_layer.id,
position:
Rect(Point2D(page_position.x.to_nearest_px() as uint,
page_position.y.to_nearest_px() as uint),
Size2D(stacking_context.bounds.size.width.to_nearest_px() as uint,
stacking_context.bounds.size.height.to_nearest_px() as uint)),
background_color: paint_layer.background_color,
scroll_policy: paint_layer.scroll_policy,
})
}
}
for kid in stacking_context.display_list.children.iter() {
build(metadata, &**kid, &page_position)
}
}
}
impl<C> PaintTask<C> where C: PaintListener + Send {
pub fn create(id: PipelineId,
port: Receiver<Msg>,
compositor: C,
constellation_chan: ConstellationChan,
font_cache_task: FontCacheTask,
failure_msg: Failure,
time_profiler_chan: TimeProfilerChan,
shutdown_chan: Sender<()>) {
let ConstellationChan(c) = constellation_chan.clone();
spawn_named_with_send_on_failure("PaintTask", task_state::PAINT, proc() {
{
// Ensures that the paint task and graphics context are destroyed before the
// shutdown message.
let mut compositor = compositor;
let native_graphics_context = compositor.get_graphics_metadata().map(
|md| NativePaintingGraphicsContext::from_metadata(&md));
let worker_threads = WorkerThreadProxy::spawn(compositor.get_graphics_metadata(),
font_cache_task,
time_profiler_chan.clone());
// FIXME: rust/#5967
let mut paint_task = PaintTask {
id: id,
port: port,
compositor: compositor,
constellation_chan: constellation_chan,
time_profiler_chan: time_profiler_chan,
native_graphics_context: native_graphics_context,
root_stacking_context: None,
paint_permission: false,
epoch: Epoch(0),
buffer_map: BufferMap::new(10000000),
worker_threads: worker_threads,
};
paint_task.start();
// Destroy all the buffers.
match paint_task.native_graphics_context.as_ref() {
Some(ctx) => paint_task.buffer_map.clear(ctx),
None => (),
}
// Tell all the worker threads to shut down.
for worker_thread in paint_task.worker_threads.iter_mut() {
worker_thread.exit()
}
}
debug!("paint_task: shutdown_chan send");
shutdown_chan.send(());
}, FailureMsg(failure_msg), c, true);
}
fn start(&mut self) {
debug!("paint_task: beginning painting loop");
loop {
match self.port.recv() {
PaintInitMsg(stacking_context) => {
self.epoch.next();
self.root_stacking_context = Some(stacking_context.clone());
if !self.paint_permission {
debug!("paint_task: paint ready msg");
let ConstellationChan(ref mut c) = self.constellation_chan;
c.send(PainterReadyMsg(self.id));
continue;
}
initialize_layers(&mut self.compositor,
self.id,
self.epoch,
&*stacking_context);
}
PaintMsg(requests) => {
if !self.paint_permission {
debug!("paint_task: paint ready msg");
let ConstellationChan(ref mut c) = self.constellation_chan;
c.send(PainterReadyMsg(self.id));
self.compositor.paint_msg_discarded();
continue;
}
let mut replies = Vec::new();
self.compositor.set_paint_state(self.id, PaintingPaintState);
for PaintRequest { buffer_requests, scale, layer_id, epoch }
in requests.into_iter() {
if self.epoch == epoch {
self.paint(&mut replies, buffer_requests, scale, layer_id);
} else {
debug!("painter epoch mismatch: {} != {}", self.epoch, epoch);
}
}
self.compositor.set_paint_state(self.id, IdlePaintState);
debug!("paint_task: returning surfaces");
self.compositor.paint(self.id, self.epoch, replies);
}
UnusedBufferMsg(unused_buffers) => {
for buffer in unused_buffers.into_iter().rev() {
self.buffer_map.insert(native_graphics_context!(self), buffer);
}
}
PaintPermissionGranted => {
self.paint_permission = true;
match self.root_stacking_context {
None => {}
Some(ref stacking_context) => {
self.epoch.next();
initialize_layers(&mut self.compositor,
self.id,
self.epoch,
&**stacking_context);
}
}
}
PaintPermissionRevoked => {
self.paint_permission = false;
}
ExitMsg(response_ch) => {
debug!("paint_task: exitmsg response send");
response_ch.map(|ch| ch.send(()));
break;
}
}
}
}
/// Retrieves an appropriately-sized layer buffer from the cache to match the requirements of
/// the given tile, or creates one if a suitable one cannot be found.
fn find_or_create_layer_buffer_for_tile(&mut self, tile: &BufferRequest, scale: f32)
-> Option<Box<LayerBuffer>> {
let width = tile.screen_rect.size.width;
let height = tile.screen_rect.size.height;
if opts::get().gpu_painting {
return None
}
match self.buffer_map.find(tile.screen_rect.size) {
Some(mut buffer) => {
buffer.rect = tile.page_rect;
buffer.screen_pos = tile.screen_rect;
buffer.resolution = scale;
buffer.native_surface.mark_wont_leak();
buffer.painted_with_cpu = true;
buffer.content_age = tile.content_age;
return Some(buffer)
}
None => {}
}
// Create an empty native surface. We mark it as not leaking
// in case it dies in transit to the compositor task.
let mut native_surface: NativeSurface =
layers::platform::surface::NativeSurfaceMethods::new(native_graphics_context!(self),
Size2D(width as i32,
height as i32),
width as i32 * 4);
native_surface.mark_wont_leak();
Some(box LayerBuffer {
native_surface: native_surface,
rect: tile.page_rect,
screen_pos: tile.screen_rect,
resolution: scale,
stride: (width * 4) as uint,
painted_with_cpu: true,
content_age: tile.content_age,
})
}
/// Paints one layer and sends the tiles back to the layer.
fn paint(&mut self,
replies: &mut Vec<(LayerId, Box<LayerBufferSet>)>,
mut tiles: Vec<BufferRequest>,
scale: f32,
layer_id: LayerId) {
time::profile(time::PaintingCategory, None, self.time_profiler_chan.clone(), || {
// Bail out if there is no appropriate stacking context.
let stacking_context = match self.root_stacking_context {
Some(ref stacking_context) => {
match display_list::find_stacking_context_with_layer_id(stacking_context,
layer_id) {
Some(stacking_context) => stacking_context,
None => return,
}
}
None => return,
};
// Divide up the layer into tiles and distribute them to workers via a simple round-
// robin strategy.
let tiles = mem::replace(&mut tiles, Vec::new());
let tile_count = tiles.len();
for (i, tile) in tiles.into_iter().enumerate() {
let thread_id = i % self.worker_threads.len();
let layer_buffer = self.find_or_create_layer_buffer_for_tile(&tile, scale);
self.worker_threads[thread_id].paint_tile(tile,
layer_buffer,
stacking_context.clone(),
scale);
}
let new_buffers = Vec::from_fn(tile_count, |i| {
let thread_id = i % self.worker_threads.len();
self.worker_threads[thread_id].get_painted_tile_buffer()
});
let layer_buffer_set = box LayerBufferSet {
buffers: new_buffers,
};
replies.push((layer_id, layer_buffer_set));
})
}
}
struct WorkerThreadProxy {
sender: Sender<MsgToWorkerThread>,
receiver: Receiver<MsgFromWorkerThread>,
}
impl WorkerThreadProxy {
fn spawn(native_graphics_metadata: Option<NativeGraphicsMetadata>,
font_cache_task: FontCacheTask,
time_profiler_chan: TimeProfilerChan)
-> Vec<WorkerThreadProxy> {
let thread_count = if opts::get().gpu_painting {
1
} else {
opts::get().layout_threads
};
Vec::from_fn(thread_count, |_| {
let (from_worker_sender, from_worker_receiver) = channel();
let (to_worker_sender, to_worker_receiver) = channel();
let native_graphics_metadata = native_graphics_metadata.clone();
let font_cache_task = font_cache_task.clone();
let time_profiler_chan = time_profiler_chan.clone();
TaskBuilder::new().native().spawn(proc() {
let mut worker_thread = WorkerThread::new(from_worker_sender,
to_worker_receiver,
native_graphics_metadata,
font_cache_task,
time_profiler_chan);
worker_thread.main();
});
WorkerThreadProxy {
receiver: from_worker_receiver,
sender: to_worker_sender,
}
})
}
fn paint_tile(&mut self,
tile: BufferRequest,
layer_buffer: Option<Box<LayerBuffer>>,
stacking_context: Arc<StackingContext>,
scale: f32) {
self.sender.send(PaintTileMsgToWorkerThread(tile, layer_buffer, stacking_context, scale))
}
fn get_painted_tile_buffer(&mut self) -> Box<LayerBuffer> {
match self.receiver.recv() {
PaintedTileMsgFromWorkerThread(layer_buffer) => layer_buffer,
}
}
fn exit(&mut self) {
self.sender.send(ExitMsgToWorkerThread)
}
}
struct WorkerThread {
sender: Sender<MsgFromWorkerThread>,
receiver: Receiver<MsgToWorkerThread>,
native_graphics_context: Option<NativePaintingGraphicsContext>,
font_context: Box<FontContext>,
time_profiler_sender: TimeProfilerChan,
}
impl WorkerThread {
fn new(sender: Sender<MsgFromWorkerThread>,
receiver: Receiver<MsgToWorkerThread>,
native_graphics_metadata: Option<NativeGraphicsMetadata>,
font_cache_task: FontCacheTask,
time_profiler_sender: TimeProfilerChan)
-> WorkerThread {
WorkerThread {
sender: sender,
receiver: receiver,
native_graphics_context: native_graphics_metadata.map(|metadata| {
NativePaintingGraphicsContext::from_metadata(&metadata)
}),
font_context: box FontContext::new(font_cache_task.clone()),
time_profiler_sender: time_profiler_sender,
}
}
fn main(&mut self) {
loop {
match self.receiver.recv() {
ExitMsgToWorkerThread => break,
PaintTileMsgToWorkerThread(tile, layer_buffer, stacking_context, scale) => {
let draw_target = self.optimize_and_paint_tile(&tile, stacking_context, scale);
let buffer = self.create_layer_buffer_for_painted_tile(&tile,
layer_buffer,
draw_target,
scale);
self.sender.send(PaintedTileMsgFromWorkerThread(buffer))
}
}
}
}
fn optimize_and_paint_tile(&mut self,
tile: &BufferRequest,
stacking_context: Arc<StackingContext>,
scale: f32)
-> DrawTarget {
let size = Size2D(tile.screen_rect.size.width as i32, tile.screen_rect.size.height as i32);
let draw_target = if !opts::get().gpu_painting {
DrawTarget::new(SkiaBackend, size, B8G8R8A8)
} else {
// FIXME(pcwalton): Cache the components of draw targets (texture color buffer,
// paintbuffers) instead of recreating them.
let draw_target = DrawTarget::new_with_fbo(SkiaBackend,
native_graphics_context!(self),
size,
B8G8R8A8);
draw_target.make_current();
draw_target
};
{
// Build the paint context.
let mut paint_context = PaintContext {
draw_target: draw_target.clone(),
font_ctx: &mut self.font_context,
page_rect: tile.page_rect,
screen_rect: tile.screen_rect,
transient_clip_rect: None,
};
// Apply the translation to paint the tile we want.
let tile_bounds = tile.page_rect;
let matrix: Matrix2D<AzFloat> = Matrix2D::identity();
let matrix = matrix.scale(scale as AzFloat, scale as AzFloat);
let matrix = matrix.translate(-tile_bounds.origin.x as AzFloat,
-tile_bounds.origin.y as AzFloat);
// Clear the buffer.
paint_context.clear();
// Draw the display list.
profile(time::PaintingPerTileCategory, None, self.time_profiler_sender.clone(), || {
stacking_context.optimize_and_draw_into_context(&mut paint_context,
&tile.page_rect,
&matrix,
None);
paint_context.draw_target.flush();
});
}
draw_target
}
fn create_layer_buffer_for_painted_tile(&mut self,
tile: &BufferRequest,
layer_buffer: Option<Box<LayerBuffer>>,
draw_target: DrawTarget,
scale: f32)
-> Box<LayerBuffer> {
// Extract the texture from the draw target and place it into its slot in the buffer. If
// using CPU painting, upload it first.
//
// FIXME(pcwalton): We should supply the texture and native surface *to* the draw target in
// GPU painting mode, so that it doesn't have to recreate it.
if !opts::get().gpu_painting {
let mut buffer = layer_buffer.unwrap();
draw_target.snapshot().get_data_surface().with_data(|data| {
buffer.native_surface.upload(native_graphics_context!(self), data);
debug!("painting worker thread uploading to native surface {:d}",
buffer.native_surface.get_id() as int);
});
return buffer
}
// GPU painting path:
draw_target.make_current();
let StolenGLResources {
surface: native_surface
} = draw_target.steal_gl_resources().unwrap();
// We mark the native surface as not leaking in case the surfaces
// die on their way to the compositor task.
let mut native_surface: NativeSurface =
NativeSurfaceAzureMethods::from_azure_surface(native_surface);
native_surface.mark_wont_leak();
box LayerBuffer {
native_surface: native_surface,
rect: tile.page_rect,
screen_pos: tile.screen_rect,
resolution: scale,
stride: (tile.screen_rect.size.width * 4) as uint,
painted_with_cpu: false,
content_age: tile.content_age,
}
}
}
enum MsgToWorkerThread {
ExitMsgToWorkerThread,
PaintTileMsgToWorkerThread(BufferRequest, Option<Box<LayerBuffer>>, Arc<StackingContext>, f32),
}
enum MsgFromWorkerThread {
PaintedTileMsgFromWorkerThread(Box<LayerBuffer>),
}