fix clippy warnings, mainly for linux

Notes:
- Warnings related to unsafe code has not been touched.
- The number of warnings has been reduced from 527 to 3.
- A few lints has been allowed globally, for convenience.

Fixes:
- fixed macros to use `$` in `$crate::`.
- broke some long lines for readability.
- solved some unneded mutable references.
- simplified unneeded vecs for arrays.
- simplified unneeded explicit returns.
- simplified unneeded redundant conversions.
- simplified fn signatures returning unit type.
- simplified verbose comparisons with booleans.
- simplified unnecessary explicit dereferences.
- allowed some functions with too many args.
- implemented `Default` for several items.
- ...among others.

src/graphics.rs

@@ -202,18 +202,13 @@ impl VertexFormat {
     }
 }
 
-#[derive(Clone, Copy, PartialEq, Debug)]
+#[derive(Clone, Copy, Debug, Default, PartialEq)]
 pub enum VertexStep {
+    #[default]
     PerVertex,
     PerInstance,
 }
 
-impl Default for VertexStep {
-    fn default() -> VertexStep {
-        VertexStep::PerVertex
-    }
-}
-
 #[derive(Clone, Debug)]
 pub struct BufferLayout {
     pub stride: i32,
@@ -643,10 +638,11 @@ impl From<Comparison> for GLenum {
 
 /// Specifies how incoming RGBA values (source) and the RGBA in framebuffer (destination)
 /// are combined.
-#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+#[derive(Debug, Default, PartialEq, Eq, Clone, Copy)]
 pub enum Equation {
     /// Adds source and destination. Source and destination are multiplied
     /// by blending parameters before addition.
+    #[default]
     Add,
     /// Subtracts destination from source. Source and destination are
     /// multiplied by blending parameters before subtraction.
@@ -675,12 +671,6 @@ pub enum BlendFactor {
     SourceAlphaSaturate,
 }
 
-impl Default for Equation {
-    fn default() -> Equation {
-        Equation::Add
-    }
-}
-
 #[derive(Debug, PartialEq, Clone, Copy)]
 pub enum PrimitiveType {
     Triangles,
@@ -882,6 +872,12 @@ pub struct ElapsedQuery {
     gl_query: GLuint,
 }
 
+impl Default for ElapsedQuery {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl ElapsedQuery {
     pub fn new() -> ElapsedQuery {
         ElapsedQuery { gl_query: 0 }
@@ -964,7 +960,7 @@ impl ElapsedQuery {
     ///
     /// Implemented as `glDeleteQueries(...)` on OpenGL/WebGL platforms.
     pub fn delete(&mut self) {
-        unsafe { glDeleteQueries(1, &mut self.gl_query) }
+        unsafe { glDeleteQueries(1, &self.gl_query) }
         self.gl_query = 0;
     }
 }
@@ -1082,8 +1078,8 @@ pub struct ContextInfo {
     /// allowing to see which glsl versions are actually supported.
     /// Unfortunately, it only works on GL4.3+... and even there it is not quite correct.
     ///
-    /// miniquad will take a guess based on GL_VERSION_STRING, current platform and implementation details.
-    /// Would be all false on metal.
+    /// miniquad will take a guess based on GL_VERSION_STRING, current platform and implementation
+    /// details. Would be all false on metal.
     pub glsl_support: GlslSupport,
     /// List of platform-dependent features that miniquad failed to make cross-platforms
     /// and therefore they might be missing.
@@ -1104,8 +1100,10 @@ impl ContextInfo {
 pub trait RenderingBackend {
     fn info(&self) -> ContextInfo;
     /// For metal context's ShaderSource should contain MSL source string, for GL - glsl.
+    ///
     /// If in doubt, _most_ OpenGL contexts support "#version 100" glsl shaders.
-    /// So far miniquad never encountered where it can create a rendering context, but `version 100` shaders are not supported.
+    /// So far miniquad never encountered where it can create a rendering context,
+    /// but `version 100` shaders are not supported.
     ///
     /// Typical `new_shader` invocation for an MSL and `glsl version 100` sources:
     /// ```ignore
@@ -1239,13 +1237,14 @@ pub trait RenderingBackend {
     /// is recommended instead.
     fn render_pass_texture(&self, render_pass: RenderPass) -> TextureId {
         let textures = self.render_pass_color_attachments(render_pass);
+        #[allow(clippy::len_zero)]
         if textures.len() == 0 {
             panic!("depth-only render pass");
         }
         if textures.len() != 1 {
             panic!("multiple render target render pass");
         }
-        return textures[0];
+        textures[0]
     }
     /// For depth-only render pass returns empty slice.
     fn render_pass_color_attachments(&self, render_pass: RenderPass) -> &[TextureId];
@@ -1289,29 +1288,29 @@ pub trait RenderingBackend {
 
     /// Delete GPU buffer, leaving handle unmodified.
     ///
-    /// More high-level code on top of miniquad probably is going to call this in Drop implementation of some
-    /// more RAII buffer object.
+    /// More high-level code on top of miniquad probably is going to call this in Drop
+    /// implementation of some more RAII buffer object.
     ///
-    /// There is no protection against using deleted buffers later. However its not an UB in OpenGl and thats why
-    /// this function is not marked as unsafe
+    /// There is no protection against using deleted buffers later. However its not an UB in OpenGl
+    /// and thats why this function is not marked as unsafe
     fn delete_buffer(&mut self, buffer: BufferId);
 
     /// Delete GPU texture, leaving handle unmodified.
     ///
-    /// More high-level code on top of miniquad probably is going to call this in Drop implementation of some
-    /// more RAII buffer object.
+    /// More high-level code on top of miniquad probably is going to call this in Drop
+    /// implementation of some more RAII buffer object.
     ///
-    /// There is no protection against using deleted textures later. However its not a CPU-level UB and thats why
-    /// this function is not marked as unsafe
+    /// There is no protection against using deleted textures later. However its not a CPU-level UB
+    /// and thats why this function is not marked as unsafe
     fn delete_texture(&mut self, texture: TextureId);
 
     /// Delete GPU program, leaving handle unmodified.
     ///
-    /// More high-level code on top of miniquad probably is going to call this in Drop implementation of some
-    /// more RAII buffer object.
+    /// More high-level code on top of miniquad probably is going to call this in Drop
+    /// implementation of some more RAII buffer object.
     ///
-    /// There is no protection against using deleted programs later. However its not a CPU-level Porgram and thats why
-    /// this function is not marked as unsafe
+    /// There is no protection against using deleted programs later. However its not a CPU-level
+    /// Porgram and thats why this function is not marked as unsafe
     fn delete_shader(&mut self, program: ShaderId);
 
     /// Set a new viewport rectangle.

src/graphics/gl.rs

@@ -521,6 +521,12 @@ pub struct GlContext {
     pub(crate) info: ContextInfo,
 }
 
+impl Default for GlContext {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl GlContext {
     pub fn new() -> GlContext {
         unsafe {
@@ -767,7 +773,7 @@ impl GlContext {
                 glStencilFuncSeparate(
                     GL_BACK,
                     back.test_func.into(),
-                    back.test_ref.into(),
+                    back.test_ref,
                     back.test_mask,
                 );
                 glStencilMaskSeparate(GL_BACK, back.write_mask);
@@ -810,6 +816,7 @@ impl GlContext {
     }
 }
 
+#[allow(clippy::field_reassign_with_default)]
 fn gl_info() -> ContextInfo {
     let version_string = unsafe { glGetString(super::gl::GL_VERSION) };
     let gl_version_string = unsafe { std::ffi::CStr::from_ptr(version_string as _) }
@@ -826,7 +833,6 @@ fn gl_info() -> ContextInfo {
     let features = Features {
         instancing: !gl2,
         resolve_attachments: !webgl1 && !gl2,
-        ..Default::default()
     };
 
     let mut glsl_support = GlslSupport::default();
@@ -872,7 +878,7 @@ fn gl_info() -> ContextInfo {
         backend: Backend::OpenGl,
         gl_version_string,
         glsl_support,
-        features: features,
+        features,
     }
 }
 
@@ -1005,11 +1011,8 @@ impl RenderingBackend for GlContext {
     ) {
         let mut t = self.textures.get(texture);
         t.resize(self, width, height, source);
-        match texture.0 {
-            TextureIdInner::Managed(tex_id) => {
-                self.textures.0[tex_id].params = t.params;
-            }
-            _ => {}
+        if let TextureIdInner::Managed(tex_id) = texture.0 {
+            self.textures.0[tex_id].params = t.params;
         };
     }
     fn texture_read_pixels(&mut self, texture: TextureId, source: &mut [u8]) {
@@ -1455,8 +1458,7 @@ impl RenderingBackend for GlContext {
                     TextureOrRenderbuffer::Renderbuffer(id) => id,
                 };
                 unsafe {
-                    self.cache
-                        .bind_texture(n, texture.params.kind.into(), raw);
+                    self.cache.bind_texture(n, texture.params.kind.into(), raw);
                     glUniform1i(gl_loc, n as i32);
                 }
             }
@@ -1524,13 +1526,11 @@ impl RenderingBackend for GlContext {
                         gl_vbuf: vb.gl_buf,
                     });
                 }
-            } else {
-                if cached_attr.is_some() {
-                    unsafe {
-                        glDisableVertexAttribArray(attr_index as GLuint);
-                    }
-                    *cached_attr = None;
+            } else if cached_attr.is_some() {
+                unsafe {
+                    glDisableVertexAttribArray(attr_index as GLuint);
                 }
+                *cached_attr = None;
             }
         }
     }
@@ -1541,7 +1541,7 @@ impl RenderingBackend for GlContext {
 
         let mut offset = 0;
 
-        for (_, uniform) in shader.uniforms.iter().enumerate() {
+        for uniform in shader.uniforms.iter() {
             use UniformType::*;
 
             assert!(
@@ -1550,8 +1550,8 @@ impl RenderingBackend for GlContext {
             );
 
             unsafe {
-                let data = (uniform_ptr as *const f32).offset(offset as isize);
-                let data_int = (uniform_ptr as *const i32).offset(offset as isize);
+                let data = (uniform_ptr as *const f32).add(offset);
+                let data_int = (uniform_ptr as *const i32).add(offset);
 
                 if let Some(gl_loc) = uniform.gl_loc {
                     match uniform.uniform_type {

src/graphics/gl/cache.rs

@@ -80,11 +80,9 @@ impl GlCache {
                 self.bind_buffer(target, self.stored_vertex_buffer, None);
                 self.stored_vertex_buffer = 0;
             }
-        } else {
-            if self.stored_index_buffer != 0 {
-                self.bind_buffer(target, self.stored_index_buffer, self.stored_index_type);
-                self.stored_index_buffer = 0;
-            }
+        } else if self.stored_index_buffer != 0 {
+            self.bind_buffer(target, self.stored_index_buffer, self.stored_index_type);
+            self.stored_index_buffer = 0;
         }
     }
 
@@ -135,9 +133,7 @@ impl GlCache {
             let cached_attr = &mut self.attributes[attr_index];
 
             if cached_attr.is_some() {
-                unsafe {
-                    glDisableVertexAttribArray(attr_index as GLuint)
-                };
+                unsafe { glDisableVertexAttribArray(attr_index as GLuint) };
             }
             *cached_attr = None;
         }

src/lib.rs

@@ -1,4 +1,11 @@
 #![doc = include_str!("../README.md")]
+#![allow(
+    clippy::collapsible_if,
+    clippy::unused_unit,
+    clippy::identity_op,
+    clippy::missing_safety_doc
+)]
+
 pub mod conf;
 mod event;
 pub mod fs;

src/native/egl.rs

@@ -278,7 +278,8 @@ pub unsafe fn create_egl_context(
     sample_count: i32,
 ) -> Result<(EGLContext, EGLConfig, EGLDisplay), EglError> {
     let display = (egl.eglGetDisplay.unwrap())(display as _);
-    if display == /* EGL_NO_DISPLAY */ null_mut() {
+    if display.is_null() {
+        // == EGL_NO_DISPLAY
         return Err(EglError::NoDisplay);
     }
 
@@ -288,7 +289,7 @@ pub unsafe fn create_egl_context(
 
     let alpha_size = if alpha { 8 } else { 0 };
     #[rustfmt::skip]
-    let cfg_attributes = vec![
+    let cfg_attributes = [
         EGL_SURFACE_TYPE, EGL_WINDOW_BIT,
         EGL_RED_SIZE, 8,
         EGL_GREEN_SIZE, 8,
@@ -340,7 +341,7 @@ pub unsafe fn create_egl_context(
     if !exact_cfg_found {
         config = available_cfgs[0];
     }
-    let ctx_attributes = vec![EGL_CONTEXT_CLIENT_VERSION, 2, EGL_NONE];
+    let ctx_attributes = [EGL_CONTEXT_CLIENT_VERSION, 2, EGL_NONE];
     let context = (egl.eglCreateContext.unwrap())(
         display,
         config,
@@ -351,5 +352,5 @@ pub unsafe fn create_egl_context(
         return Err(EglError::CreateContextFailed);
     }
 
-    return Ok((context, config, display));
+    Ok((context, config, display))
 }

src/native/gl.rs

@@ -319,6 +319,7 @@ macro_rules! gl_loader {
         }
 
         $(
+            #[allow(clippy::too_many_arguments)]
             pub unsafe fn $fn($($arg: $t),*) -> $res {
                 __pfns::$fn.unwrap()( $($arg),* )
             }