Merge pull request #3 from lunixbochs/calayer

use CALayer for macOS backend

Author: john01dav

Cargo.toml

@@ -26,7 +26,9 @@ x11-dl = "2.19.1"
 winapi = "0.3.9"
 
 [target.'cfg(target_os = "macos")'.dependencies]
+cocoa = "0.24.0"
 core-graphics = "0.22.3"
+foreign-types = "0.3.0"
 objc = "0.2.7"
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]
@@ -49,4 +51,4 @@ features = ["jpeg"]
 [target.'cfg(not(target_arch = "wasm32"))'.dev-dependencies]
 # Turn rayon back on everywhere else; creating the separate entry resets the features to default.
 image = "0.23.14"
-rayon = "1.5.1"
+rayon = "1.5.1"

src/cg.rs

@@ -1,47 +1,44 @@
 use crate::{GraphicsContextImpl, SoftBufferError};
 use raw_window_handle::{HasRawWindowHandle, AppKitHandle};
-use objc::runtime::Object;
 use core_graphics::base::{kCGBitmapByteOrder32Little, kCGImageAlphaNoneSkipFirst, kCGRenderingIntentDefault};
 use core_graphics::color_space::CGColorSpace;
-use core_graphics::context::CGContext;
 use core_graphics::data_provider::CGDataProvider;
-use core_graphics::geometry::{CGPoint, CGSize, CGRect};
 use core_graphics::image::CGImage;
-use core_graphics::sys;
+
+use cocoa::base::{id, nil};
+use cocoa::appkit::{NSView, NSViewWidthSizable, NSViewHeightSizable};
+use cocoa::quartzcore::{CALayer, ContentsGravity};
+use foreign_types::ForeignType;
+
+use std::sync::Arc;
 
 pub struct CGImpl {
-    view: *mut Object,
+    layer: CALayer,
 }
 
 impl CGImpl {
     pub unsafe fn new<W: HasRawWindowHandle>(handle: AppKitHandle) -> Result<Self, SoftBufferError<W>> {
-        let window = handle.ns_window as *mut Object;
-        let view = handle.ns_view as *mut Object;
-        let cls = class!(NSGraphicsContext);
-        let graphics_context: *mut Object = msg_send![cls, graphicsContextWithWindow:window];
-        if graphics_context.is_null() {
-            return Err(SoftBufferError::PlatformError(Some("Graphics context is null".into()), None));
-        }
-        let _: () = msg_send![cls, setCurrentContext:graphics_context];
-        Ok(
-            Self {
-                view,
-            }
-        )
+        let view = handle.ns_view as id;
+        let layer = CALayer::new();
+        let subview: id = NSView::alloc(nil).initWithFrame_(view.frame());
+        layer.set_contents_gravity(ContentsGravity::TopLeft);
+        layer.set_needs_display_on_bounds_change(false);
+        subview.setLayer(layer.id());
+        subview.setAutoresizingMask_(NSViewWidthSizable | NSViewHeightSizable);
+
+        view.addSubview_(subview); // retains subview (+1) = 2
+        let _: () = msg_send![subview, release]; // releases subview (-1) = 1
+        Ok(Self{layer})
     }
 }
 
 impl GraphicsContextImpl for CGImpl {
     unsafe fn set_buffer(&mut self, buffer: &[u32], width: u16, height: u16) {
-        let cls = class!(NSGraphicsContext);
-        let graphics_context: *mut Object = msg_send![cls, currentContext];
-        let context_ptr: *mut sys::CGContext = msg_send![graphics_context, CGContext];
-        let context = CGContext::from_existing_context_ptr(context_ptr);
         let color_space = CGColorSpace::create_device_rgb();
-        let slice = std::slice::from_raw_parts(
+        let data = std::slice::from_raw_parts(
             buffer.as_ptr() as *const u8,
-            buffer.len() * 4);
-        let data_provider = CGDataProvider::from_slice(slice);
+            buffer.len() * 4).to_vec();
+        let data_provider = CGDataProvider::from_buffer(Arc::new(data));
         let image = CGImage::new(
             width as usize,
             height as usize,
@@ -54,11 +51,6 @@ impl GraphicsContextImpl for CGImpl {
             false,
             kCGRenderingIntentDefault,
         );
-        let frame: CGRect = msg_send![self.view, frame];
-        // In Core Graphics, (0, 0) is bottom left, not top left
-        let origin = CGPoint { x: 0f64, y: frame.size.height };
-        let size = CGSize { width: width as f64, height: -(height as f64) };
-        let rect = CGRect { origin, size };
-        context.draw_image(rect, &image);
+        self.layer.set_contents(image.as_ptr() as id);
     }
 }