Add the entire tree from raw-gl-handle

Including @prokopyl's PR that adds more X11 error handling:
micahrj/raw-gl-context#15

Commit: prokopyl@raw-gl-context@98cd3cf1104ee254a67e3fed30e4e6b2ae2b6821 (with `cargo fmt`)
Branch base: b68a05b

Author: robbert-vdh

src/gl/lib.rs

@@ -0,0 +1,100 @@
+use raw_window_handle::HasRawWindowHandle;
+
+use std::ffi::c_void;
+use std::marker::PhantomData;
+
+#[cfg(target_os = "windows")]
+mod win;
+#[cfg(target_os = "windows")]
+use win as platform;
+
+#[cfg(target_os = "linux")]
+mod x11;
+#[cfg(target_os = "linux")]
+use crate::x11 as platform;
+
+#[cfg(target_os = "macos")]
+mod macos;
+#[cfg(target_os = "macos")]
+use macos as platform;
+
+#[derive(Clone, Debug)]
+pub struct GlConfig {
+    pub version: (u8, u8),
+    pub profile: Profile,
+    pub red_bits: u8,
+    pub blue_bits: u8,
+    pub green_bits: u8,
+    pub alpha_bits: u8,
+    pub depth_bits: u8,
+    pub stencil_bits: u8,
+    pub samples: Option<u8>,
+    pub srgb: bool,
+    pub double_buffer: bool,
+    pub vsync: bool,
+}
+
+impl Default for GlConfig {
+    fn default() -> Self {
+        GlConfig {
+            version: (3, 2),
+            profile: Profile::Core,
+            red_bits: 8,
+            blue_bits: 8,
+            green_bits: 8,
+            alpha_bits: 8,
+            depth_bits: 24,
+            stencil_bits: 8,
+            samples: None,
+            srgb: true,
+            double_buffer: true,
+            vsync: false,
+        }
+    }
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum Profile {
+    Compatibility,
+    Core,
+}
+
+#[derive(Debug)]
+pub enum GlError {
+    InvalidWindowHandle,
+    VersionNotSupported,
+    CreationFailed(platform::CreationFailedError),
+}
+
+pub struct GlContext {
+    context: platform::GlContext,
+    phantom: PhantomData<*mut ()>,
+}
+
+impl GlContext {
+    pub unsafe fn create(
+        parent: &impl HasRawWindowHandle,
+        config: GlConfig,
+    ) -> Result<GlContext, GlError> {
+        platform::GlContext::create(parent, config).map(|context| GlContext {
+            context,
+            phantom: PhantomData,
+        })
+    }
+
+    pub unsafe fn make_current(&self) {
+        self.context.make_current();
+    }
+
+    pub unsafe fn make_not_current(&self) {
+        self.context.make_not_current();
+    }
+
+    pub fn get_proc_address(&self, symbol: &str) -> *const c_void {
+        self.context.get_proc_address(symbol)
+    }
+
+    pub fn swap_buffers(&self) {
+        self.context.swap_buffers();
+    }
+}

src/gl/macos.rs

@@ -0,0 +1,147 @@
+use std::ffi::c_void;
+use std::str::FromStr;
+
+use raw_window_handle::{HasRawWindowHandle, RawWindowHandle};
+
+use cocoa::appkit::{
+    NSOpenGLContext, NSOpenGLContextParameter, NSOpenGLPFAAccelerated, NSOpenGLPFAAlphaSize,
+    NSOpenGLPFAColorSize, NSOpenGLPFADepthSize, NSOpenGLPFADoubleBuffer, NSOpenGLPFAMultisample,
+    NSOpenGLPFAOpenGLProfile, NSOpenGLPFASampleBuffers, NSOpenGLPFASamples, NSOpenGLPFAStencilSize,
+    NSOpenGLPixelFormat, NSOpenGLProfileVersion3_2Core, NSOpenGLProfileVersion4_1Core,
+    NSOpenGLProfileVersionLegacy, NSOpenGLView, NSView,
+};
+use cocoa::base::{id, nil, YES};
+
+use core_foundation::base::TCFType;
+use core_foundation::bundle::{CFBundleGetBundleWithIdentifier, CFBundleGetFunctionPointerForName};
+use core_foundation::string::CFString;
+
+use objc::{msg_send, sel, sel_impl};
+
+use crate::{GlConfig, GlError, Profile};
+
+pub type CreationFailedError = ();
+pub struct GlContext {
+    view: id,
+    context: id,
+}
+
+impl GlContext {
+    pub unsafe fn create(
+        parent: &impl HasRawWindowHandle,
+        config: GlConfig,
+    ) -> Result<GlContext, GlError> {
+        let handle = if let RawWindowHandle::MacOS(handle) = parent.raw_window_handle() {
+            handle
+        } else {
+            return Err(GlError::InvalidWindowHandle);
+        };
+
+        if handle.ns_view.is_null() {
+            return Err(GlError::InvalidWindowHandle);
+        }
+
+        let parent_view = handle.ns_view as id;
+
+        let version = if config.version < (3, 2) && config.profile == Profile::Compatibility {
+            NSOpenGLProfileVersionLegacy
+        } else if config.version == (3, 2) && config.profile == Profile::Core {
+            NSOpenGLProfileVersion3_2Core
+        } else if config.version > (3, 2) && config.profile == Profile::Core {
+            NSOpenGLProfileVersion4_1Core
+        } else {
+            return Err(GlError::VersionNotSupported);
+        };
+
+        #[rustfmt::skip]
+        let mut attrs = vec![
+            NSOpenGLPFAOpenGLProfile as u32, version as u32,
+            NSOpenGLPFAColorSize as u32, (config.red_bits + config.blue_bits + config.green_bits) as u32,
+            NSOpenGLPFAAlphaSize as u32, config.alpha_bits as u32,
+            NSOpenGLPFADepthSize as u32, config.depth_bits as u32,
+            NSOpenGLPFAStencilSize as u32, config.stencil_bits as u32,
+            NSOpenGLPFAAccelerated as u32,
+        ];
+
+        if config.samples.is_some() {
+            #[rustfmt::skip]
+            attrs.extend_from_slice(&[
+                NSOpenGLPFAMultisample as u32,
+                NSOpenGLPFASampleBuffers as u32, 1,
+                NSOpenGLPFASamples as u32, config.samples.unwrap() as u32,
+            ]);
+        }
+
+        if config.double_buffer {
+            attrs.push(NSOpenGLPFADoubleBuffer as u32);
+        }
+
+        attrs.push(0);
+
+        let pixel_format = NSOpenGLPixelFormat::alloc(nil).initWithAttributes_(&attrs);
+
+        if pixel_format == nil {
+            return Err(GlError::CreationFailed(()));
+        }
+
+        let view =
+            NSOpenGLView::alloc(nil).initWithFrame_pixelFormat_(parent_view.frame(), pixel_format);
+
+        if view == nil {
+            return Err(GlError::CreationFailed(()));
+        }
+
+        view.setWantsBestResolutionOpenGLSurface_(YES);
+
+        let () = msg_send![view, retain];
+        NSOpenGLView::display_(view);
+        parent_view.addSubview_(view);
+
+        let context: id = msg_send![view, openGLContext];
+        let () = msg_send![context, retain];
+
+        context.setValues_forParameter_(
+            &(config.vsync as i32),
+            NSOpenGLContextParameter::NSOpenGLCPSwapInterval,
+        );
+
+        let () = msg_send![pixel_format, release];
+
+        Ok(GlContext { view, context })
+    }
+
+    pub unsafe fn make_current(&self) {
+        self.context.makeCurrentContext();
+    }
+
+    pub unsafe fn make_not_current(&self) {
+        NSOpenGLContext::clearCurrentContext(self.context);
+    }
+
+    pub fn get_proc_address(&self, symbol: &str) -> *const c_void {
+        let symbol_name = CFString::from_str(symbol).unwrap();
+        let framework_name = CFString::from_str("com.apple.opengl").unwrap();
+        let framework =
+            unsafe { CFBundleGetBundleWithIdentifier(framework_name.as_concrete_TypeRef()) };
+        let addr = unsafe {
+            CFBundleGetFunctionPointerForName(framework, symbol_name.as_concrete_TypeRef())
+        };
+        addr as *const c_void
+    }
+
+    pub fn swap_buffers(&self) {
+        unsafe {
+            self.context.flushBuffer();
+            let () = msg_send![self.view, setNeedsDisplay: YES];
+        }
+    }
+}
+
+impl Drop for GlContext {
+    fn drop(&mut self) {
+        unsafe {
+            let () = msg_send![self.context, release];
+            let () = msg_send![self.view, release];
+        }
+    }
+}