Merge pull request #1697 from iced-rs/text-glyphon

Text shaping, font fallback, and `iced_wgpu` overhaul

3 files changed, 100 insertions, 41 deletions

diff --git a/wgpu/src/buffer.rs b/wgpu/src/buffer.rs
index 7c092d0b..c210dd4e 100644
--- a/wgpu/src/buffer.rs
+++ b/wgpu/src/buffer.rs
@@ -1,3 +1,89 @@
 //! Utilities for buffer operations.
 pub mod dynamic;
 pub mod r#static;
+
+use std::marker::PhantomData;
+use std::ops::RangeBounds;
+
+#[derive(Debug)]
+pub struct Buffer<T> {
+    label: &'static str,
+    size: u64,
+    usage: wgpu::BufferUsages,
+    raw: wgpu::Buffer,
+    type_: PhantomData<T>,
+}
+
+impl<T: bytemuck::Pod> Buffer<T> {
+    pub fn new(
+        device: &wgpu::Device,
+        label: &'static str,
+        amount: usize,
+        usage: wgpu::BufferUsages,
+    ) -> Self {
+        let size = next_copy_size::<T>(amount);
+
+        let raw = device.create_buffer(&wgpu::BufferDescriptor {
+            label: Some(label),
+            size,
+            usage,
+            mapped_at_creation: false,
+        });
+
+        Self {
+            label,
+            size,
+            usage,
+            raw,
+            type_: PhantomData,
+        }
+    }
+
+    pub fn resize(&mut self, device: &wgpu::Device, new_count: usize) -> bool {
+        let new_size = (std::mem::size_of::<T>() * new_count) as u64;
+
+        if self.size < new_size {
+            self.raw = device.create_buffer(&wgpu::BufferDescriptor {
+                label: Some(self.label),
+                size: new_size,
+                usage: self.usage,
+                mapped_at_creation: false,
+            });
+
+            self.size = new_size;
+
+            true
+        } else {
+            false
+        }
+    }
+
+    pub fn write(
+        &self,
+        queue: &wgpu::Queue,
+        offset_count: usize,
+        contents: &[T],
+    ) {
+        queue.write_buffer(
+            &self.raw,
+            (std::mem::size_of::<T>() * offset_count) as u64,
+            bytemuck::cast_slice(contents),
+        );
+    }
+
+    pub fn slice(
+        &self,
+        bounds: impl RangeBounds<wgpu::BufferAddress>,
+    ) -> wgpu::BufferSlice<'_> {
+        self.raw.slice(bounds)
+    }
+}
+
+fn next_copy_size<T>(amount: usize) -> u64 {
+    let align_mask = wgpu::COPY_BUFFER_ALIGNMENT - 1;
+
+    (((std::mem::size_of::<T>() * amount).next_power_of_two() as u64
+        + align_mask)
+        & !align_mask)
+        .max(wgpu::COPY_BUFFER_ALIGNMENT)
+}
diff --git a/wgpu/src/buffer/dynamic.rs b/wgpu/src/buffer/dynamic.rs
index 88289b98..43fc47ac 100644
--- a/wgpu/src/buffer/dynamic.rs
+++ b/wgpu/src/buffer/dynamic.rs
@@ -112,25 +112,8 @@ impl<T: ShaderType + WriteInto> Buffer<T> {
     }
 
     /// Write the contents of this dynamic buffer to the GPU via staging belt command.
-    pub fn write(
-        &mut self,
-        device: &wgpu::Device,
-        staging_belt: &mut wgpu::util::StagingBelt,
-        encoder: &mut wgpu::CommandEncoder,
-    ) {
-        let size = self.cpu.get_ref().len();
-
-        if let Some(buffer_size) = wgpu::BufferSize::new(size as u64) {
-            let mut buffer = staging_belt.write_buffer(
-                encoder,
-                &self.gpu,
-                0,
-                buffer_size,
-                device,
-            );
-
-            buffer.copy_from_slice(self.cpu.get_ref());
-        }
+    pub fn write(&mut self, queue: &wgpu::Queue) {
+        queue.write_buffer(&self.gpu, 0, self.cpu.get_ref());
     }
 
     // Gets the aligned offset at the given index from the CPU buffer.
@@ -184,7 +167,7 @@ impl Internal {
     }
 
     /// Returns bytearray of aligned CPU buffer.
-    pub(super) fn get_ref(&self) -> &Vec<u8> {
+    pub(super) fn get_ref(&self) -> &[u8] {
         match self {
             Internal::Uniform(buf) => buf.as_ref(),
             #[cfg(not(target_arch = "wasm32"))]
diff --git a/wgpu/src/buffer/static.rs b/wgpu/src/buffer/static.rs
index ef87422f..d8ae116e 100644
--- a/wgpu/src/buffer/static.rs
+++ b/wgpu/src/buffer/static.rs
@@ -2,8 +2,7 @@ use bytemuck::{Pod, Zeroable};
 use std::marker::PhantomData;
 use std::mem;
 
-//128 triangles/indices
-const DEFAULT_STATIC_BUFFER_COUNT: wgpu::BufferAddress = 128;
+const DEFAULT_COUNT: wgpu::BufferAddress = 128;
 
 /// A generic buffer struct useful for items which have no alignment requirements
 /// (e.g. Vertex, Index buffers) & no dynamic offsets.
@@ -25,7 +24,7 @@ impl<T: Pod + Zeroable> Buffer<T> {
         label: &'static str,
         usages: wgpu::BufferUsages,
     ) -> Self {
-        let size = (mem::size_of::<T>() as u64) * DEFAULT_STATIC_BUFFER_COUNT;
+        let size = (mem::size_of::<T>() as u64) * DEFAULT_COUNT;
 
         Self {
             offsets: Vec::new(),
@@ -57,9 +56,13 @@ impl<T: Pod + Zeroable> Buffer<T> {
         let size = (mem::size_of::<T>() * new_count) as u64;
 
         if self.size < size {
+            self.size =
+                (mem::size_of::<T>() * (new_count + new_count / 2)) as u64;
+
+            self.gpu =
+                Self::gpu_buffer(device, self.label, self.size, self.usages);
+
             self.offsets.clear();
-            self.size = size;
-            self.gpu = Self::gpu_buffer(device, self.label, size, self.usages);
             true
         } else {
             false
@@ -71,28 +74,15 @@ impl<T: Pod + Zeroable> Buffer<T> {
     /// Returns the size of the written bytes.
     pub fn write(
         &mut self,
-        device: &wgpu::Device,
-        staging_belt: &mut wgpu::util::StagingBelt,
-        encoder: &mut wgpu::CommandEncoder,
+        queue: &wgpu::Queue,
         offset: u64,
         content: &[T],
     ) -> u64 {
         let bytes = bytemuck::cast_slice(content);
         let bytes_size = bytes.len() as u64;
 
-        if let Some(buffer_size) = wgpu::BufferSize::new(bytes_size) {
-            let mut buffer = staging_belt.write_buffer(
-                encoder,
-                &self.gpu,
-                offset,
-                buffer_size,
-                device,
-            );
-
-            buffer.copy_from_slice(bytes);
-
-            self.offsets.push(offset);
-        }
+        queue.write_buffer(&self.gpu, offset, bytes);
+        self.offsets.push(offset);
 
         bytes_size
     }