Remove some insidious implicit copying in the TextRunScanner.

This commit is contained in:
Brian J. Burg 2012-10-09 18:17:33 -07:00
parent 26d5cfb509
commit d979b9fbc6

View file

@ -63,46 +63,42 @@ impl TextRunScanner {
fn scan_for_runs(ctx: &LayoutContext) {
// if reused, must be reset.
assert !self.in_clump;
let in_boxes = self.flow.inline().boxes;
assert in_boxes.len() > 0;
assert self.flow.inline().boxes.len() > 0;
debug!("scanning %u boxes for text runs...", in_boxes.len());
do self.flow.inline().boxes.swap |in_boxes| {
debug!("scanning %u boxes for text runs...", in_boxes.len());
let temp_boxes = DVec();
let mut prev_box: @RenderBox = in_boxes[0];
let temp_boxes = DVec();
let mut prev_box: @RenderBox = in_boxes[0];
for uint::range(0, in_boxes.len()) |i| {
debug!("considering box: %?", in_boxes[i].debug_str());
for uint::range(0, in_boxes.len()) |i| {
debug!("considering box: %?", in_boxes[i].debug_str());
let can_coalesce_with_prev = i > 0 && boxes_can_be_coalesced(prev_box, in_boxes[i]);
let can_coalesce_with_prev = i > 0 && boxes_can_be_coalesced(prev_box, in_boxes[i]);
match (self.in_clump, can_coalesce_with_prev) {
// start a new clump
(false, _) => { self.reset_clump_to_index(i); },
// extend clump
(true, true) => { self.clump_end = i; },
// boundary detected; flush and start new clump
(true, false) => {
self.flush_clump_to_list(ctx, in_boxes, &temp_boxes);
self.reset_clump_to_index(i);
}
};
prev_box = in_boxes[i];
}
// handle remaining clumps
if self.in_clump {
self.flush_clump_to_list(ctx, in_boxes, &temp_boxes);
}
match (self.in_clump, can_coalesce_with_prev) {
// start a new clump
(false, _) => { self.reset_clump_to_index(i); },
// extend clump
(true, true) => { self.clump_end = i; },
// boundary detected; flush and start new clump
(true, false) => {
self.flush_clump_to_list(ctx, &temp_boxes);
self.reset_clump_to_index(i);
}
};
prev_box = in_boxes[i];
}
// handle remaining clumps
if self.in_clump {
self.flush_clump_to_list(ctx, &temp_boxes);
}
debug!("swapping out boxes.");
// swap out old and new box list of flow
self.flow.inline().boxes.set(dvec::unwrap(temp_boxes));
debug!("new inline flow boxes:");
do self.flow.inline().boxes.each |box| {
debug!("%s", box.debug_str()); true
debug!("swapping out boxes.");
// swap out old and new box list of flow, by supplying
// temp boxes as return value to boxes.swap |...|
dvec::unwrap(temp_boxes)
}
// helper functions
@ -125,12 +121,12 @@ impl TextRunScanner {
self.in_clump = true;
}
fn flush_clump_to_list(ctx: &LayoutContext, temp_boxes: &DVec<@RenderBox>) {
fn flush_clump_to_list(ctx: &LayoutContext,
in_boxes: &[@RenderBox], temp_boxes: &DVec<@RenderBox>) {
assert self.in_clump;
debug!("flushing when start=%?,end=%?", self.clump_start, self.clump_end);
let in_boxes = self.flow.inline().boxes;
let is_singleton = (self.clump_start == self.clump_end);
let is_text_clump = match in_boxes[self.clump_start] {
@UnscannedTextBox(*) => true,
@ -154,11 +150,11 @@ impl TextRunScanner {
let mut run_str : ~str = ~"";
// TODO: is using ropes to construct the merged text any faster?
do uint::range(self.clump_start, self.clump_end+1) |i| {
run_str = str::append(run_str, in_boxes[i].raw_text()); true
run_str = str::append(copy run_str, in_boxes[i].raw_text()); true
}
// TODO: use actual font for corresponding DOM node to create text run.
let run = TextRun(&*ctx.font_cache.get_test_font(), move run_str);
let box_guts = TextBoxData(@run, 0, run.text.len());
let run = @TextRun(&*ctx.font_cache.get_test_font(), move run_str);
let box_guts = TextBoxData(run, 0, run.text.len());
debug!("pushing when start=%?,end=%?", self.clump_start, self.clump_end);
temp_boxes.push(@TextBox(copy *in_boxes[self.clump_start].d(), box_guts));
}