Avoid taking mutable references when filling/creating render targets from textures (asny#555)

* Avoid &mut self in textures

* Remove muts

* Fix headless lint

Author: asny

examples/headless/src/main.rs

@@ -39,7 +39,7 @@ fn main() {
     );
 
     // Create a color texture to render into
-    let mut texture = Texture2D::new_empty::<[u8; 4]>(
+    let texture = Texture2D::new_empty::<[u8; 4]>(
         &context,
         viewport.width,
         viewport.height,
@@ -51,7 +51,7 @@ fn main() {
     );
 
     // Also create a depth texture to support depth testing
-    let mut depth_texture = DepthTexture2D::new::<f32>(
+    let depth_texture = DepthTexture2D::new::<f32>(
         &context,
         viewport.width,
         viewport.height,

examples/image/src/main.rs

@@ -88,7 +88,7 @@ pub async fn run() {
             ..Default::default()
         };
 
-        let mut target = Texture2D::new_empty::<[f16; 4]>(
+        let target = Texture2D::new_empty::<[f16; 4]>(
             &context,
             viewport.width,
             viewport.height,

examples/multisample/src/main.rs

@@ -134,7 +134,7 @@ pub fn main() {
 
             RenderMethod::ToTexture => {
                 // Render the shapes to a non-multisample texture, and copy the color texture to the screen.
-                let mut color_texture = Texture2D::new_empty::<[u8; 4]>(
+                let color_texture = Texture2D::new_empty::<[u8; 4]>(
                     &context,
                     frame_input.viewport.width,
                     frame_input.viewport.height,
@@ -144,7 +144,7 @@ pub fn main() {
                     Wrapping::ClampToEdge,
                     Wrapping::ClampToEdge,
                 );
-                let mut depth_texture = DepthTexture2D::new::<f32>(
+                let depth_texture = DepthTexture2D::new::<f32>(
                     &context,
                     frame_input.viewport.width,
                     frame_input.viewport.height,

src/core/render_target/color_target_multisample.rs

@@ -108,7 +108,7 @@ impl<C: TextureDataType> ColorTargetMultisample<C> {
     /// Use [ColorTargetMultisample::resolve_to] to resolve to a custom non-multisample texture.
     ///
     pub fn resolve(&self) -> Texture2D {
-        let mut color_texture = Texture2D::new_empty::<C>(
+        let color_texture = Texture2D::new_empty::<C>(
             &self.context,
             self.width(),
             self.height(),

src/core/render_target/depth_target_multisample.rs

@@ -105,7 +105,7 @@ impl<D: DepthTextureDataType> DepthTargetMultisample<D> {
     /// Use [DepthTargetMultisample::resolve_to] to resolve to a custom non-multisample texture.
     ///
     pub fn resolve(&self) -> DepthTexture2D {
-        let mut depth_texture = DepthTexture2D::new::<D>(
+        let depth_texture = DepthTexture2D::new::<D>(
             &self.context,
             self.width(),
             self.height(),

src/core/render_target/multisample.rs

@@ -129,7 +129,7 @@ impl<C: TextureDataType, D: DepthTextureDataType> RenderTargetMultisample<C, D>
     /// Use [RenderTargetMultisample::resolve_color_to] to resolve to a custom non-multisample texture.
     ///
     pub fn resolve_color(&self) -> Texture2D {
-        let mut color_texture = Texture2D::new_empty::<C>(
+        let color_texture = Texture2D::new_empty::<C>(
             &self.context,
             self.color.width(),
             self.color.height(),
@@ -148,7 +148,7 @@ impl<C: TextureDataType, D: DepthTextureDataType> RenderTargetMultisample<C, D>
     /// Use [RenderTargetMultisample::resolve_depth_to] to resolve to a custom non-multisample texture.
     ///
     pub fn resolve_depth(&self) -> DepthTexture2D {
-        let mut depth_texture = DepthTexture2D::new::<D>(
+        let depth_texture = DepthTexture2D::new::<D>(
             &self.context,
             self.width(),
             self.height(),
@@ -164,7 +164,7 @@ impl<C: TextureDataType, D: DepthTextureDataType> RenderTargetMultisample<C, D>
     /// Use [RenderTargetMultisample::resolve_to] to resolve to custom non-multisample textures.
     ///
     pub fn resolve(&self) -> (Texture2D, DepthTexture2D) {
-        let mut color_texture = Texture2D::new_empty::<C>(
+        let color_texture = Texture2D::new_empty::<C>(
             &self.context,
             self.color.width(),
             self.color.height(),
@@ -174,7 +174,7 @@ impl<C: TextureDataType, D: DepthTextureDataType> RenderTargetMultisample<C, D>
             Wrapping::ClampToEdge,
             Wrapping::ClampToEdge,
         );
-        let mut depth_texture = DepthTexture2D::new::<D>(
+        let depth_texture = DepthTexture2D::new::<D>(
             &self.context,
             self.width(),
             self.height(),

src/core/texture/depth_texture2d.rs

@@ -55,7 +55,7 @@ impl DepthTexture2D {
     /// Returns a [DepthTarget] which can be used to clear, write to and read from this texture.
     /// Combine this together with a [ColorTarget] with [RenderTarget::new] to be able to write to both a depth and color target at the same time.
     ///
-    pub fn as_depth_target(&mut self) -> DepthTarget<'_> {
+    pub fn as_depth_target(&self) -> DepthTarget<'_> {
         DepthTarget::new_texture2d(&self.context, self)
     }
 

src/core/texture/depth_texture2d_array.rs

@@ -59,7 +59,7 @@ impl DepthTexture2DArray {
     /// Returns a [DepthTarget] which can be used to clear, write to and read from the given layer of this texture.
     /// Combine this together with a [ColorTarget] with [RenderTarget::new] to be able to write to both a depth and color target at the same time.
     ///
-    pub fn as_depth_target(&mut self, layer: u32) -> DepthTarget<'_> {
+    pub fn as_depth_target(&self, layer: u32) -> DepthTarget<'_> {
         DepthTarget::new_texture_2d_array(&self.context, self, layer)
     }
 

src/core/texture/depth_texture_cube_map.rs

@@ -56,7 +56,7 @@ impl DepthTextureCubeMap {
     /// Returns a [DepthTarget] which can be used to clear, write to and read from the given side of this texture.
     /// Combine this together with a [ColorTarget] with [RenderTarget::new] to be able to write to both a depth and color target at the same time.
     ///
-    pub fn as_depth_target(&mut self, side: CubeMapSide) -> DepthTarget<'_> {
+    pub fn as_depth_target(&self, side: CubeMapSide) -> DepthTarget<'_> {
         DepthTarget::new_texture_cube_map(&self.context, self, side)
     }
 

src/core/texture/texture2d.rs

@@ -130,7 +130,7 @@ impl Texture2D {
     ///
     /// **Note:** [DepthTest] is disabled if not also writing to a depth texture.
     ///
-    pub fn as_color_target(&mut self, mip_level: Option<u32>) -> ColorTarget<'_> {
+    pub fn as_color_target(&self, mip_level: Option<u32>) -> ColorTarget<'_> {
         ColorTarget::new_texture2d(&self.context, self, mip_level)
     }