render: make damage visualizer slightly less inefficient

src/damage.rs

@@ -160,7 +160,7 @@ impl DamageVisualizer {
         let entries = &*self.entries.borrow();
         let decay = self.decay.get();
         let base_color = self.color.get();
-        let mut used = Region::empty();
+        let mut used = Region::default();
         let dx = -cursor_rect.x1();
         let dy = -cursor_rect.y1();
         let decay_millis = decay.as_millis() as u64 as f32;
@@ -168,12 +168,12 @@ impl DamageVisualizer {
         let srgb = &self.color_manager.srgb_srgb().linear;
         for entry in entries.iter().rev() {
             let region = Region::new(entry.rect);
-            let region = region.subtract(&used);
+            let region = region.subtract_cow(&used);
             if region.is_not_empty() {
                 let age = (now - entry.time).as_millis() as u64 as f32 / decay_millis;
                 let color = base_color * (1.0 - age);
                 renderer.fill_boxes2(region.rects(), &color, srgb, dx, dy);
-                used = used.union(&region);
+                used = used.union_cow(&region).into_owned();
             }
         }
     }

src/gfx_api.rs

@@ -314,7 +314,7 @@ pub trait GfxFramebuffer: Debug {
 
     fn full_region(&self) -> Region {
         let (width, height) = self.physical_size();
-        Region::new2(Rect::new_sized_unchecked(0, 0, width, height))
+        Region::new(Rect::new_sized_unchecked(0, 0, width, height))
     }
 }
 

src/gfx_apis/vulkan/transfer.rs

@@ -132,7 +132,7 @@ impl VulkanShmImage {
             if tt == TransferType::Download {
                 return Err(VulkanError::UndefinedContents);
             }
-            damage = Region::new2(Rect::new_sized(0, 0, img.width as _, img.height as _).unwrap());
+            damage = Region::new(Rect::new_sized(0, 0, img.width as _, img.height as _).unwrap());
         }
 
         let copies = &mut *data.regions.borrow_mut();

src/ifs/ext_image_copy/ext_image_copy_capture_frame_v1.rs

@@ -146,7 +146,7 @@ impl ExtImageCopyCaptureFrameV1 {
                     &staging,
                     self.clone(),
                     mem.clone(),
-                    Region::new2(buffer.rect),
+                    Region::new(buffer.rect),
                 );
                 match res {
                     Ok(d) => self.session.pending_download.set(d),

src/ifs/wl_buffer.rs

@@ -240,7 +240,7 @@ impl WlBuffer {
                         *stride,
                         &self.client.state.cpu_worker,
                     )?;
-                    mem.access(|mem| tex.clone().sync_upload(mem, Region::new2(self.rect)))??;
+                    mem.access(|mem| tex.clone().sync_upload(mem, Region::new(self.rect)))??;
                     surface.shm_textures.front().tex.set(Some(tex));
                     surface.shm_textures.front().damage.clear();
                 }

src/rect/region.rs

@@ -49,7 +49,7 @@ impl Region {
             return Self::default();
         }
         if rects.len() == 1 {
-            return Self::new2(rects[0]);
+            return Self::new(rects[0]);
         }
         let rects = rects_to_bands(unsafe { mem::transmute::<&[Rect], &[RectRaw]>(rects) });
         Self {
@@ -74,6 +74,20 @@ impl Region {
         })
     }
 
+    pub fn union_cow<'a>(self: &'a Self, other: &'a Self) -> Cow<'a, Region> {
+        if self.extents.is_empty() {
+            return Cow::Borrowed(other);
+        }
+        if other.extents.is_empty() {
+            return Cow::Borrowed(self);
+        }
+        let rects = union(&self.rects, &other.rects);
+        Cow::Owned(Self {
+            rects,
+            extents: self.extents.union(other.extents),
+        })
+    }
+
     pub fn subtract(self: &Rc<Self>, other: &Rc<Self>) -> Rc<Self> {
         if self.extents.is_empty() || other.extents.is_empty() {
             return self.clone();
@@ -122,7 +136,7 @@ impl Region<u32> {
         if rects.len() == 1 {
             let mut rect = rects[0];
             rect.raw.tag = rect.raw.tag.constrain();
-            return Self::new2(rect);
+            return Self::new(rect);
         }
         let rects = rects_to_bands_tagged(unsafe {
             mem::transmute::<&[Rect<u32>], &[RectRaw<u32>]>(rects)
@@ -153,11 +167,7 @@ impl<T> Region<T>
 where
     T: Tag,
 {
-    pub fn new(rect: Rect<T>) -> Rc<Self> {
+    pub fn new(rect: Rect<T>) -> Self {
-        Rc::new(Self::new2(rect))
-    }
-
-    pub fn new2(rect: Rect<T>) -> Self {
         let mut rects = SmallVec::new();
         rects.push(rect.raw);
         Self {

src/rect/tests.rs

@@ -8,7 +8,8 @@ fn union1() {
     let r1 = Region::new(Rect::new(0, 0, 10, 10).unwrap());
     let r2_ = Region::new(Rect::new(5, 5, 15, 15).unwrap());
     let r2 = Region::new(Rect::new(10, 10, 20, 20).unwrap());
-    let r3 = r1.union(&r2).union(&r2_);
+    let r3 = r1.union_cow(&r2);
+    let r3 = r3.union_cow(&r2_);
     assert_eq!(r3.extents, Rect::new(0, 0, 20, 20).unwrap());
     assert_eq!(
         &r3.rects[..],
@@ -25,7 +26,7 @@ fn union1() {
 fn union2() {
     let r1 = Region::new(Rect::new(0, 0, 10, 10).unwrap());
     let r2 = Region::new(Rect::new(0, 10, 10, 20).unwrap());
-    let r3 = r1.union(&r2);
+    let r3 = r1.union_cow(&r2);
     assert_eq!(r3.extents, Rect::new(0, 0, 10, 20).unwrap());
     assert_eq!(&r3.rects[..], &[Rect::new(0, 0, 10, 20).unwrap().raw,]);
 }
@@ -34,7 +35,7 @@ fn union2() {
 fn subtract1() {
     let r1 = Region::new(Rect::new(0, 0, 20, 20).unwrap());
     let r2 = Region::new(Rect::new(5, 5, 15, 15).unwrap());
-    let r3 = r1.subtract(&r2);
+    let r3 = r1.subtract_cow(&r2);
     assert_eq!(r3.extents, Rect::new(0, 0, 20, 20).unwrap());
     assert_eq!(
         &r3.rects[..],

src/state.rs

@@ -1302,7 +1302,7 @@ impl State {
                 &staging,
                 capture.clone(),
                 mem.clone(),
-                Region::new2(capture.rect.at_point(0, 0)),
+                Region::new(capture.rect.at_point(0, 0)),
             )
             .map_err(ShmScreencopyError::ReadPixels)?;
         Ok(pending)

src/text.rs

@@ -544,7 +544,7 @@ impl CpuJob for RenderJob {
                 &staging,
                 data.clone(),
                 Rc::new(rt.data),
-                Region::new2(Rect::new_sized_unchecked(0, 0, rt.width, rt.height)),
+                Region::new(Rect::new_sized_unchecked(0, 0, rt.width, rt.height)),
             )
             .map_err(TextError::Upload);
         if pending.is_ok() {