From 625218bbf660527103407de9819f98144946b140 Mon Sep 17 00:00:00 2001
From: Victoria Brekenfeld <victoria@system76.com>
Date: Thu, 29 Feb 2024 17:50:05 +0100
Subject: [PATCH] shell: Delay alpha changes for minimize animations

---
 src/shell/layout/floating/mod.rs | 10 ++++++----
 src/shell/layout/tiling/mod.rs   |  9 +++++++--
 2 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/src/shell/layout/floating/mod.rs b/src/shell/layout/floating/mod.rs
index 57e016e6..3b5bf58f 100644
--- a/src/shell/layout/floating/mod.rs
+++ b/src/shell/layout/floating/mod.rs
@@ -90,18 +90,20 @@ impl Animation {
         match self {
             Animation::Tiled { .. } => 1.0,
             Animation::Minimize { start, .. } => {
-                1.0 - (Instant::now()
+                let percentage = Instant::now()
                     .duration_since(*start)
                     .min(MINIMIZE_ANIMATION_DURATION)
                     .as_secs_f32()
-                    / MINIMIZE_ANIMATION_DURATION.as_secs_f32())
+                    / MINIMIZE_ANIMATION_DURATION.as_secs_f32();
+                1.0 - ((percentage - 0.5).max(0.0) * 2.0)
             }
             Animation::Unminimize { start, .. } => {
-                Instant::now()
+                let percentage = Instant::now()
                     .duration_since(*start)
                     .min(MINIMIZE_ANIMATION_DURATION)
                     .as_secs_f32()
-                    / MINIMIZE_ANIMATION_DURATION.as_secs_f32()
+                    / MINIMIZE_ANIMATION_DURATION.as_secs_f32();
+                (percentage * 2.0).min(1.0)
             }
         }
     }
diff --git a/src/shell/layout/tiling/mod.rs b/src/shell/layout/tiling/mod.rs
index 3f53258d..ba797e90 100644
--- a/src/shell/layout/tiling/mod.rs
+++ b/src/shell/layout/tiling/mod.rs
@@ -4731,6 +4731,11 @@ where
                     })
                     .unwrap_or(*original_geo);
 
+                let alpha = if minimize_geo.is_some() {
+                    1.0 - ((percentage - 0.5).max(0.0) * 2.0)
+                } else {
+                    1.0 - percentage
+                };
 
                 let elem_geometry = mapped.geometry().to_physical_precise_round(output_scale);
                 let (w_elements, p_elements) = mapped
@@ -4739,7 +4744,7 @@ where
                         geo.loc.as_logical().to_physical_precise_round(output_scale)
                             - elem_geometry.loc,
                         Scale::from(output_scale),
-                        1.0 - percentage,
+                        alpha,
                     );
 
                 window_elements.extend(w_elements.into_iter().flat_map(|element| {
@@ -5021,7 +5026,7 @@ where
                 ..
             } = &data
             {
-                old_geo = Some((*minimize_rect, percentage));
+                old_geo = Some((*minimize_rect, (percentage * 2.0).min(1.0)));
             }
 
             let (scale, offset) = scaled_geo