pixels::PixelsBuilder::alpha_mode

src/builder.rs

@@ -17,6 +17,7 @@ pub struct PixelsBuilder<'req, 'dev, 'win, W: HasRawWindowHandle + HasRawDisplay
     surface_texture_format: Option<wgpu::TextureFormat>,
     clear_color: wgpu::Color,
     blend_state: wgpu::BlendState,
+    alpha_mode: wgpu::CompositeAlphaMode,
 }
 
 impl<'req, 'dev, 'win, W: HasRawWindowHandle + HasRawDisplayHandle>
@@ -64,6 +65,7 @@ impl<'req, 'dev, 'win, W: HasRawWindowHandle + HasRawDisplayHandle>
             surface_texture_format: None,
             clear_color: wgpu::Color::BLACK,
             blend_state: wgpu::BlendState::ALPHA_BLENDING,
+            alpha_mode: wgpu::CompositeAlphaMode::Auto,
         }
     }
 
@@ -235,6 +237,22 @@ impl<'req, 'dev, 'win, W: HasRawWindowHandle + HasRawDisplayHandle>
         self
     }
 
+    /// Sets the alpha mode.
+    ///
+    /// Default value is `Auto`.
+    ///
+    ///```
+    ///use pixels::wgpu::CompositeAlphaMode;
+    ///
+    ///let mut pixels = PixelsBuilder::new(320, 240, surface_texture)
+    ///    .alpha_mode(CompositeAlphaMode::PostMultiplied)
+    ///    .build()?;
+    ///```
+    pub fn alpha_mode(mut self, alpha_mode: wgpu::CompositeAlphaMode) -> Self {
+        self.alpha_mode = alpha_mode;
+        self
+    }
+
     /// Create a pixel buffer from the options builder.
     ///
     /// This is the private implementation shared by [`PixelsBuilder::build`] and
@@ -319,7 +337,7 @@ impl<'req, 'dev, 'win, W: HasRawWindowHandle + HasRawDisplayHandle>
         let mut pixels = Vec::with_capacity(pixels_buffer_size);
         pixels.resize_with(pixels_buffer_size, Default::default);
 
-        let alpha_mode = surface_capabilities.alpha_modes[0];
+        let alpha_mode = self.alpha_mode;
 
         // Instantiate the Pixels struct
         let context = PixelsContext {