From 4f05e2e1f16547ee53e09afaa8994a3c9921e6a6 Mon Sep 17 00:00:00 2001
From: Wez Furlong <wez@wezfurlong.org>
Date: Sat, 22 Oct 2022 19:51:52 -0700
Subject: [PATCH] render: remove redundant extra quad buffer

I can't think of a good reason for this being here.  I think I
may have been lazy about resolving the lifetime annotations
and just stuck in an extra buffer while building the original
version of this logic, and then forgot about it.

This commit resolves the lifetime annotations and directly
references the passed in buffer.

refs: https://github.com/wez/wezterm/issues/2626
---
 wezterm-gui/src/termwindow/render.rs | 22 +++++++---------------
 1 file changed, 7 insertions(+), 15 deletions(-)

diff --git a/wezterm-gui/src/termwindow/render.rs b/wezterm-gui/src/termwindow/render.rs
index 4018c9bc7..f63fd425e 100644
--- a/wezterm-gui/src/termwindow/render.rs
+++ b/wezterm-gui/src/termwindow/render.rs
@@ -1624,7 +1624,7 @@ impl super::TermWindow {
             pos.pane
                 .apply_hyperlinks(stable_range.clone(), &self.config.hyperlink_rules);
 
-            struct LineRender<'a> {
+            struct LineRender<'a, 'b> {
                 term_window: &'a mut super::TermWindow,
                 selrange: Option<SelectionRange>,
                 rectangular: bool,
@@ -1646,7 +1646,7 @@ impl super::TermWindow {
                 white_space: TextureRect,
                 filled_box: TextureRect,
                 window_is_transparent: bool,
-                layers: HeapQuadAllocator,
+                layers: &'a mut TripleLayerQuadAllocator<'b>,
                 error: Option<anyhow::Error>,
             }
 
@@ -1676,11 +1676,11 @@ impl super::TermWindow {
                 white_space,
                 filled_box,
                 window_is_transparent,
-                layers: HeapQuadAllocator::default(),
+                layers,
                 error: None,
             };
 
-            impl<'a> LineRender<'a> {
+            impl<'a, 'b> LineRender<'a, 'b> {
                 fn render_line(
                     &mut self,
                     stable_top: StableRowIndex,
@@ -1763,9 +1763,7 @@ impl super::TermWindow {
                             false
                         };
                         if !expired && !hover_changed {
-                            cached_quad
-                                .layers
-                                .apply_to(&mut TripleLayerQuadAllocator::Heap(&mut self.layers))?;
+                            cached_quad.layers.apply_to(self.layers)?;
                             self.term_window.update_next_frame_time(cached_quad.expires);
                             return Ok(());
                         }
@@ -1832,7 +1830,7 @@ impl super::TermWindow {
                     let expires = self.term_window.has_animation.borrow().as_ref().cloned();
                     self.term_window.update_next_frame_time(next_due);
 
-                    buf.apply_to(&mut TripleLayerQuadAllocator::Heap(&mut self.layers))?;
+                    buf.apply_to(self.layers)?;
 
                     let quad_value = LineQuadCacheValue {
                         layers: buf,
@@ -1855,7 +1853,7 @@ impl super::TermWindow {
                 }
             }
 
-            impl<'a> WithPaneLines for LineRender<'a> {
+            impl<'a, 'b> WithPaneLines for LineRender<'a, 'b> {
                 fn with_lines_mut(&mut self, stable_top: StableRowIndex, lines: &mut [&mut Line]) {
                     for (line_idx, line) in lines.iter().enumerate() {
                         if let Err(err) = self.render_line(stable_top, line_idx, line) {
@@ -1870,7 +1868,6 @@ impl super::TermWindow {
             if let Some(error) = render.error.take() {
                 return Err(error);
             }
-            render.layers.apply_to(layers)?;
         }
 
         /*
@@ -1881,11 +1878,6 @@ impl super::TermWindow {
         metrics::histogram!("paint_pane_opengl.lines", start.elapsed());
         log::trace!("lines elapsed {:?}", start.elapsed());
 
-        let start = Instant::now();
-        drop(layers);
-        metrics::histogram!("paint_pane_opengl.drop.quads", start.elapsed());
-        log::trace!("quad drop elapsed {:?}", start.elapsed());
-
         Ok(())
     }