Add a bulk buffer building helper

src/gfx.rs

@@ -1,10 +1,12 @@
 mod bind_group;
+mod buffer;
 mod context;
 mod renderer;
 mod texture;
 
 pub use self::{
     bind_group::{BindGroupBuilder, BindGroupLayoutBuilder},
+    buffer::BulkBufferBuilder,
     context::Context,
     renderer::Renderer,
     texture::{Texture, TextureBuilder},

src/gfx/buffer.rs

@@ -0,0 +1,47 @@
+use bytemuck::NoUninit;
+use wgpu::util::DeviceExt;
+
+use super::Context;
+
+#[derive(Debug)]
+pub struct BulkBufferBuilder<'a> {
+    descriptors: Vec<wgpu::util::BufferInitDescriptor<'a>>,
+    current_usage: wgpu::BufferUsages,
+}
+
+impl<'a> BulkBufferBuilder<'a> {
+    pub fn new() -> Self {
+        Self {
+            descriptors: vec![],
+            current_usage: wgpu::BufferUsages::UNIFORM,
+        }
+    }
+
+    pub fn with_usage(mut self, usage: wgpu::BufferUsages) -> Self {
+        self.current_usage = usage;
+        self
+    }
+
+    pub fn with_buffer(mut self, label: &'a str, contents: &'a [u8]) -> Self {
+        let descriptor = wgpu::util::BufferInitDescriptor {
+            label: Some(label),
+            contents,
+            usage: self.current_usage,
+        };
+
+        self.descriptors.push(descriptor);
+        self
+    }
+
+    pub fn with_bytemuck_buffer<A: NoUninit>(mut self, label: &'a str, contents: &'a [A]) -> Self {
+        self.with_buffer(label, bytemuck::cast_slice(contents))
+    }
+
+    pub fn build(self, context: &Context) -> Vec<wgpu::Buffer> {
+        let mut buffers = vec![];
+        for descriptor in self.descriptors {
+            buffers.push(context.device.create_buffer_init(&descriptor));
+        }
+        buffers
+    }
+}