wgpu fix & inital decoder infra

nokhwa-core/src/buffer.rs

@@ -16,6 +16,8 @@
 
 use crate::{frame_format::SourceFrameFormat, types::Resolution};
 use bytes::Bytes;
+use image::ImageBuffer;
+use crate::error::NokhwaError;
 
 /// A buffer returned by a camera to accommodate custom decoding.
 /// Contains information of Resolution, the buffer's [`FrameFormat`], and the buffer.
@@ -152,6 +154,9 @@ impl Buffer {
     }
 }
 
+#[cfg(feature = "wgpu-types")]
+use wgpu::{Extent3d, TextureDescriptor, TextureDimension, TextureFormat, TextureUsages, ImageCopyTexture, TextureAspect, ImageDataLayout};
+
 #[cfg(feature = "wgpu-types")]
 impl Buffer {
     #[cfg_attr(feature = "docs-features", doc(cfg(feature = "wgpu-types")))]
@@ -160,12 +165,10 @@ impl Buffer {
     /// If the frame cannot be captured or the resolution is 0 on any axis, this will error.
     fn frame_texture<'a>(
         &mut self,
-        device: &WgpuDevice,
-        queue: &WgpuQueue,
+        device: &wgpu::Device,
+        queue: &wgpu::Queue,
         label: Option<&'a str>,
-    ) -> Result<WgpuTexture, NokhwaError> {
-        use crate::pixel_format::RgbAFormat;
-        use std::num::NonZeroU32;
+    ) -> Result<wgpu::Texture, NokhwaError> {
         let frame = self.frame()?.decode_image::<RgbAFormat>()?;
     
         let texture_size = Extent3d {
@@ -182,17 +185,11 @@ impl Buffer {
             dimension: TextureDimension::D2,
             format: TextureFormat::Rgba8UnormSrgb,
             usage: TextureUsages::TEXTURE_BINDING | TextureUsages::COPY_DST,
+            view_formats: &[TextureFormat::Rgba8UnormSrgb],
         });
     
-        let width_nonzero = match NonZeroU32::try_from(4 * frame.width()) {
-            Ok(w) => Some(w),
-            Err(why) => return Err(NokhwaError::ReadFrameError(why.to_string())),
-        };
-    
-        let height_nonzero = match NonZeroU32::try_from(frame.height()) {
-            Ok(h) => Some(h),
-            Err(why) => return Err(NokhwaError::ReadFrameError(why.to_string())),
-        };
+        let width_nonzero = 4 * frame.width();
+        let height_nonzero = frame.height();
     
         queue.write_texture(
             ImageCopyTexture {

nokhwa-core/src/decoder.rs

@@ -0,0 +1,33 @@
+use std::ops::Deref;
+use image::{ImageBuffer, Pixel};
+use serde::de::Error;
+use crate::buffer::Buffer;
+use crate::frame_format::{SourceFrameFormat};
+
+/// Trait to define a struct that can decode a [`Buffer`]
+pub trait Decoder {
+    /// Formats that the decoder can decode.
+    const ALLOWED_FORMATS: &'static [SourceFrameFormat];
+    /// Output pixel type (e.g. [`Rgb<u8>`](image::Rgb))
+    type Pixel: Pixel;
+    /// Container for [`Self::Pixel`] - must have the same [`Pixel::Subpixel`]
+    type Container: Deref<Target = [Pixel::Subpixel]>;
+    /// Error that the decoder will output (use [`NokhwaError`] if you're not sure)
+    type Error: Error;
+
+    /// Decode function.
+    fn decode(&mut self, buffer: Buffer) -> Result<ImageBuffer<Self::Pixel, Self::Container>, Self::Error>;
+}
+
+/// Decoder that can be used statically (struct contains no state)
+/// 
+/// This is useful for times that a simple function is all that is required. 
+pub trait StaticDecoder: Decoder {
+    fn decode_static(buffer: Buffer) -> Result<ImageBuffer<Self::Pixel, Self::Container>, Self::Error>;
+}
+
+/// Decoder that does not change its internal state. 
+pub trait IdemptDecoder: Decoder {
+    fn decode_nm(buffer: Buffer) -> Result<ImageBuffer<Self::Pixel, Self::Container>, Self::Error>;
+}
+

nokhwa-core/src/lib.rs

@@ -25,3 +25,4 @@ pub mod format_filter;
 pub mod frame_format;
 pub mod traits;
 pub mod types;
+pub mod decoder;