From 4ede482ab5ff6364237f5f4626784075045d5dfb Mon Sep 17 00:00:00 2001
From: Héctor Ramón Jiménez <hector0193@gmail.com>
Date: Wed, 5 Apr 2023 18:41:40 +0200
Subject: Present new frame only when damaged in `iced_tiny_skia`

---
 tiny_skia/src/backend.rs           |  6 ++++--
 tiny_skia/src/window/compositor.rs | 14 ++++++++------
 2 files changed, 12 insertions(+), 8 deletions(-)

(limited to 'tiny_skia/src')

diff --git a/tiny_skia/src/backend.rs b/tiny_skia/src/backend.rs
index 8bc2321c..0b534bba 100644
--- a/tiny_skia/src/backend.rs
+++ b/tiny_skia/src/backend.rs
@@ -50,7 +50,7 @@ impl Backend {
         viewport: &Viewport,
         background_color: Color,
         overlay: &[T],
-    ) {
+    ) -> bool {
         let physical_size = viewport.physical_size();
 
         let damage = if self.last_background_color == background_color
@@ -62,7 +62,7 @@ impl Backend {
         };
 
         if damage.is_empty() {
-            return;
+            return false;
         }
 
         self.last_primitives = primitives.to_vec();
@@ -179,6 +179,8 @@ impl Backend {
 
         #[cfg(feature = "svg")]
         self.vector_pipeline.trim_cache();
+
+        true
     }
 
     fn draw_primitive(
diff --git a/tiny_skia/src/window/compositor.rs b/tiny_skia/src/window/compositor.rs
index cea1cabf..6e4bb6ef 100644
--- a/tiny_skia/src/window/compositor.rs
+++ b/tiny_skia/src/window/compositor.rs
@@ -106,7 +106,7 @@ pub fn present<Theme, T: AsRef<str>>(
 ) -> Result<(), compositor::SurfaceError> {
     let physical_size = viewport.physical_size();
 
-    backend.draw(
+    let drawn = backend.draw(
         &mut tiny_skia::PixmapMut::from_bytes(
             bytemuck::cast_slice_mut(&mut surface.buffer),
             physical_size.width,
@@ -120,11 +120,13 @@ pub fn present<Theme, T: AsRef<str>>(
         overlay,
     );
 
-    surface.window.set_buffer(
-        &surface.buffer,
-        physical_size.width as u16,
-        physical_size.height as u16,
-    );
+    if drawn {
+        surface.window.set_buffer(
+            &surface.buffer,
+            physical_size.width as u16,
+            physical_size.height as u16,
+        );
+    }
 
     Ok(())
 }
-- 
cgit