[PATCH 1/2] ui/cocoa: Add cursor composition

From: Akihiko Odaki <akihiko.odaki@daynix.com>
To: "Paolo Bonzini" <pbonzini@redhat.com>,
	"Marc-André Lureau" <marcandre.lureau@redhat.com>,
	"Daniel P. Berrangé" <berrange@redhat.com>,
	"Thomas Huth" <thuth@redhat.com>,
	"Philippe Mathieu-Daudé" <philmd@linaro.org>,
	"Peter Maydell" <peter.maydell@linaro.org>,
	"Gerd Hoffmann" <kraxel@redhat.com>,
	"Dmitry Fleytman" <dmitry.fleytman@gmail.com>
Cc: qemu-devel@nongnu.org, Akihiko Odaki <akihiko.odaki@daynix.com>
Subject: [PATCH 1/2] ui/cocoa: Add cursor composition
Date: Mon, 18 Mar 2024 16:58:13 +0900	[thread overview]
Message-ID: <20240318-cursor-v1-1-0bbe6c382217@daynix.com> (raw)
In-Reply-To: <20240318-cursor-v1-0-0bbe6c382217@daynix.com>

Add accelerated cursor composition to ui/cocoa. This does not only
improve performance for display devices that exposes the capability to
the guest according to dpy_cursor_define_supported(), but fixes the
cursor display for devices that unconditionally expects the availability
of the capability (e.g., virtio-gpu).

The common pattern to implement accelerated cursor composition is to
replace the cursor and warp it so that the replaced cursor is shown at
the correct position on the guest display. Unfortunately, ui/cocoa
cannot do the same because warping the cursor position interfers with
the mouse input so it uses CALayer instead; although it is not
specialized for cursor composition, it still can compose images with
hardware acceleration.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
---
 meson.build |  3 +-
 ui/cocoa.m  | 97 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 99 insertions(+), 1 deletion(-)

diff --git a/meson.build b/meson.build
index b375248a7614..b198ca2972ed 100644
--- a/meson.build
+++ b/meson.build
@@ -1044,7 +1044,8 @@ if get_option('attr').allowed()
   endif
 endif
 
-cocoa = dependency('appleframeworks', modules: ['Cocoa', 'CoreVideo'],
+cocoa = dependency('appleframeworks',
+                   modules: ['Cocoa', 'CoreVideo', 'QuartzCore'],
                    required: get_option('cocoa'))
 
 vmnet = dependency('appleframeworks', modules: 'vmnet', required: get_option('vmnet'))
diff --git a/ui/cocoa.m b/ui/cocoa.m
index fa879d7dcd4b..c13c2a01e947 100644
--- a/ui/cocoa.m
+++ b/ui/cocoa.m
@@ -25,6 +25,7 @@
 #include "qemu/osdep.h"
 
 #import <Cocoa/Cocoa.h>
+#import <QuartzCore/QuartzCore.h>
 #include <crt_externs.h>
 
 #include "qemu/help-texts.h"
@@ -92,12 +93,16 @@ static void cocoa_switch(DisplayChangeListener *dcl,
                          DisplaySurface *surface);
 
 static void cocoa_refresh(DisplayChangeListener *dcl);
+static void cocoa_mouse_set(DisplayChangeListener *dcl, int x, int y, int on);
+static void cocoa_cursor_define(DisplayChangeListener *dcl, QEMUCursor *cursor);
 
 static const DisplayChangeListenerOps dcl_ops = {
     .dpy_name          = "cocoa",
     .dpy_gfx_update = cocoa_update,
     .dpy_gfx_switch = cocoa_switch,
     .dpy_refresh = cocoa_refresh,
+    .dpy_mouse_set = cocoa_mouse_set,
+    .dpy_cursor_define = cocoa_cursor_define,
 };
 static DisplayChangeListener dcl = {
     .ops = &dcl_ops,
@@ -313,6 +318,11 @@ @interface QemuCocoaView : NSView
     BOOL isMouseGrabbed;
     BOOL isAbsoluteEnabled;
     CFMachPortRef eventsTap;
+    CALayer *cursorLayer;
+    QEMUCursor *cursor;
+    int mouseX;
+    int mouseY;
+    int mouseOn;
 }
 - (void) switchSurface:(pixman_image_t *)image;
 - (void) grabMouse;
@@ -365,6 +375,12 @@ - (id)initWithFrame:(NSRect)frameRect
 #if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_VERSION_14_0
         [self setClipsToBounds:YES];
 #endif
+        [self setWantsLayer:YES];
+        cursorLayer = [[CALayer alloc] init];
+        [cursorLayer setAnchorPoint:CGPointMake(0, 1)];
+        [cursorLayer setAutoresizingMask:kCALayerMaxXMargin |
+                                         kCALayerMinYMargin];
+        [[self layer] addSublayer:cursorLayer];
 
     }
     return self;
@@ -445,6 +461,72 @@ - (void) unhideCursor
     [NSCursor unhide];
 }
 
+- (void)setMouseX:(int)x y:(int)y on:(int)on
+{
+    CGPoint position;
+
+    mouseX = x;
+    mouseY = y;
+    mouseOn = on;
+
+    position.x = mouseX;
+    position.y = screen.height - mouseY;
+
+    [CATransaction begin];
+    [CATransaction setDisableActions:YES];
+    [cursorLayer setPosition:position];
+    [cursorLayer setHidden:!mouseOn];
+    [CATransaction commit];
+}
+
+- (void)setCursor:(QEMUCursor *)given_cursor
+{
+    CGDataProviderRef provider;
+    CGImageRef image;
+    CGRect bounds = CGRectZero;
+
+    cursor_unref(cursor);
+    cursor = given_cursor;
+
+    if (!cursor) {
+        return;
+    }
+
+    cursor_ref(cursor);
+
+    bounds.size.width = cursor->width;
+    bounds.size.height = cursor->height;
+
+    provider = CGDataProviderCreateWithData(
+        NULL,
+        cursor->data,
+        cursor->width * cursor->height * 4,
+        NULL
+    );
+
+    image = CGImageCreate(
+        cursor->width, //width
+        cursor->height, //height
+        8, //bitsPerComponent
+        32, //bitsPerPixel
+        cursor->width * 4, //bytesPerRow
+        CGColorSpaceCreateWithName(kCGColorSpaceSRGB), //colorspace
+        kCGBitmapByteOrder32Little | kCGImageAlphaFirst, //bitmapInfo
+        provider, //provider
+        NULL, //decode
+        0, //interpolate
+        kCGRenderingIntentDefault //intent
+    );
+
+    CGDataProviderRelease(provider);
+    [CATransaction begin];
+    [CATransaction setDisableActions:YES];
+    [cursorLayer setBounds:bounds];
+    [cursorLayer setContents:(id)image];
+    [CATransaction commit];
+    CGImageRelease(image);
+}
+
 - (void) drawRect:(NSRect) rect
 {
     COCOA_DEBUG("QemuCocoaView: drawRect\n");
@@ -1982,6 +2064,21 @@ static void cocoa_refresh(DisplayChangeListener *dcl)
     [pool release];
 }
 
+static void cocoa_mouse_set(DisplayChangeListener *dcl, int x, int y, int on)
+{
+    dispatch_async(dispatch_get_main_queue(), ^{
+        [cocoaView setMouseX:x y:y on:on];
+    });
+}
+
+static void cocoa_cursor_define(DisplayChangeListener *dcl, QEMUCursor *cursor)
+{
+    dispatch_async(dispatch_get_main_queue(), ^{
+        BQL_LOCK_GUARD();
+        [cocoaView setCursor:qemu_console_get_cursor(dcl->con)];
+    });
+}
+
 static void cocoa_display_init(DisplayState *ds, DisplayOptions *opts)
 {
     NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];

-- 
2.44.0


