softbuffer/src/cg.rs

82 lines
2.8 KiB
Rust

use crate::SoftBufferError;
use core_graphics::base::{
kCGBitmapByteOrder32Little, kCGImageAlphaNoneSkipFirst, kCGRenderingIntentDefault,
};
use core_graphics::color_space::CGColorSpace;
use core_graphics::data_provider::CGDataProvider;
use core_graphics::image::CGImage;
use raw_window_handle::AppKitWindowHandle;
use cocoa::appkit::{NSView, NSViewHeightSizable, NSViewWidthSizable, NSWindow};
use cocoa::base::{id, nil};
use cocoa::quartzcore::{transaction, CALayer, ContentsGravity};
use foreign_types::ForeignType;
use std::sync::Arc;
pub struct CGImpl {
layer: CALayer,
window: id,
}
impl CGImpl {
pub unsafe fn new(handle: AppKitWindowHandle) -> Result<Self, SoftBufferError> {
let window = handle.ns_window as id;
let window: id = msg_send![window, retain];
let view = handle.ns_view as id;
let layer = CALayer::new();
unsafe {
let subview: id = NSView::alloc(nil).initWithFrame_(NSView::frame(view));
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, window })
}
pub(crate) unsafe fn set_buffer(&mut self, buffer: &[u32], width: u16, height: u16) {
let color_space = CGColorSpace::create_device_rgb();
let data =
unsafe { std::slice::from_raw_parts(buffer.as_ptr() as *const u8, buffer.len() * 4) }
.to_vec();
let data_provider = CGDataProvider::from_buffer(Arc::new(data));
let image = CGImage::new(
width as usize,
height as usize,
8,
32,
(width * 4) as usize,
&color_space,
kCGBitmapByteOrder32Little | kCGImageAlphaNoneSkipFirst,
&data_provider,
false,
kCGRenderingIntentDefault,
);
// The CALayer has a default action associated with a change in the layer contents, causing
// a quarter second fade transition to happen every time a new buffer is applied. This can
// be mitigated by wrapping the operation in a transaction and disabling all actions.
transaction::begin();
transaction::set_disable_actions(true);
unsafe {
self.layer
.set_contents_scale(self.window.backingScaleFactor());
self.layer.set_contents(image.as_ptr() as id);
};
transaction::commit();
}
}
impl Drop for CGImpl {
fn drop(&mut self) {
unsafe {
let _: () = msg_send![self.window, release];
}
}
}