1 files changed, 150 insertions, 0 deletions
diff --git a/flowy/src/motion/mod.rs b/flowy/src/motion/mod.rs
new file mode 100644
index 0000000..acb1396
--- /dev/null
+++ b/flowy/src/motion/mod.rs
@@ -0,0 +1,150 @@
+pub mod dec;
+pub mod enc;
+
+use std::mem::size_of;
+use wgpu::{
+    Buffer, BufferUsages, CommandEncoder, Device, Extent3d, ImageCopyTexture, Origin3d, Queue,
+    Texture, TextureDescriptor, TextureDimension, TextureFormat, TextureUsages,
+};
+
+pub struct Params {
+    pub width: usize,
+    pub height: usize,
+    pub extent: Extent3d,
+    pub block_width: usize,
+    pub block_height: usize,
+    pub blocks: usize,
+}
+
+pub struct RoundParams {
+    pub swap: usize,
+}
+
+pub struct CommonBuffers {
+    textures: [Texture; 2],
+    offsets: Buffer,
+    offsets_download: Option<Buffer>,
+    debug_output: Option<Texture>,
+    texture_download: Option<Buffer>,
+}
+
+#[repr(C)]
+pub struct BlockOffset {
+    score: f32,
+    _pad: u32,
+    offset: [f32; 2],
+}
+
+impl CommonBuffers {
+    pub fn create(device: &Device, params: &Params) -> Self {
+        let textures = [(), ()].map(|_| {
+            device.create_texture(&TextureDescriptor {
+                label: None,
+                size: params.extent,
+                mip_level_count: 1,
+                sample_count: 1,
+                dimension: TextureDimension::D2,
+                format: TextureFormat::Bgra8Unorm,
+                usage: TextureUsages::TEXTURE_BINDING
+                    | TextureUsages::COPY_DST
+                    | TextureUsages::COPY_SRC,
+                view_formats: &[],
+            })
+        });
+
+        let debug_output = Some(device.create_texture(&TextureDescriptor {
+            label: None,
+            size: params.extent,
+            mip_level_count: 1,
+            sample_count: 1,
+            dimension: TextureDimension::D2,
+            format: TextureFormat::Bgra8Unorm,
+            usage: TextureUsages::STORAGE_BINDING | TextureUsages::COPY_SRC,
+            view_formats: &[],
+        }));
+
+        let texture_download = Some(device.create_buffer(&wgpu::BufferDescriptor {
+            label: None,
+            size: (params.width * params.height * 4) as u64,
+            usage: BufferUsages::COPY_DST | BufferUsages::MAP_READ,
+            mapped_at_creation: false,
+        }));
+
+        let offsets = device.create_buffer(&wgpu::BufferDescriptor {
+            label: None,
+            size: (params.blocks * size_of::<BlockOffset>()) as u64,
+            usage: BufferUsages::COPY_DST | BufferUsages::STORAGE,
+            mapped_at_creation: false,
+        });
+        let offsets_download = Some(device.create_buffer(&wgpu::BufferDescriptor {
+            label: None,
+            size: (params.blocks * size_of::<BlockOffset>()) as u64,
+            usage: BufferUsages::COPY_DST | BufferUsages::MAP_READ,
+            mapped_at_creation: false,
+        }));
+
+        Self {
+            debug_output,
+            textures,
+            offsets_download,
+            offsets,
+            texture_download,
+        }
+    }
+
+    pub fn upload(&self, queue: &Queue, params: &Params, rp: &RoundParams, buffer: &[u8]) {
+        queue.write_texture(
+            ImageCopyTexture {
+                aspect: wgpu::TextureAspect::All,
+                mip_level: 0,
+                origin: Origin3d::ZERO,
+                texture: &self.textures[rp.swap],
+            },
+            buffer,
+            wgpu::ImageDataLayout {
+                offset: 0,
+                bytes_per_row: Some(params.extent.width * 4),
+                rows_per_image: Some(params.extent.height),
+            },
+            params.extent,
+        );
+    }
+
+    pub fn prepare_texture_download(
+        &self,
+        encoder: &mut CommandEncoder,
+        params: &Params,
+        rp: &RoundParams,
+    ) {
+        encoder.copy_texture_to_buffer(
+            wgpu::ImageCopyTexture {
+                texture: &self.textures[rp.swap],
+                mip_level: 0,
+                origin: wgpu::Origin3d::ZERO,
+                aspect: wgpu::TextureAspect::All,
+            },
+            wgpu::ImageCopyBuffer {
+                buffer: self.texture_download.as_ref().unwrap(),
+                layout: wgpu::ImageDataLayout {
+                    offset: 0,
+                    bytes_per_row: Some(params.extent.width * 4),
+                    rows_per_image: Some(params.extent.height),
+                },
+            },
+            params.extent,
+        );
+    }
+
+    pub fn download(&self, device: &Device, buffer: &mut [u8]) {
+        let buffer_slice = self.texture_download.as_ref().unwrap().slice(..);
+        let (sender, receiver) = oneshot::channel();
+        buffer_slice.map_async(wgpu::MapMode::Read, move |r| sender.send(r).unwrap());
+        device.poll(wgpu::Maintain::Wait);
+        receiver.recv().unwrap().unwrap();
+        {
+            let view = buffer_slice.get_mapped_range();
+            buffer.copy_from_slice(&view[..]);
+        }
+        self.texture_download.as_ref().unwrap().unmap();
+    }
+}