Skip to content

Commit

Permalink
app: [macOS] implement non-blocking window resizing
Browse files Browse the repository at this point in the history 
Despite the option to control the main thread event loop, some gestures
still block the event loop until completion. This change disables the
blocking resize gestures and implements a non-blocking replacement.

A complete replacement is left for future work, or the implementation of
golang/go#64755.

Signed-off-by: Elias Naur <[email protected]>
  • Loading branch information
@eliasnaur
eliasnaur committed Feb 8, 2024
1 parent 5e5d164 commit 768e597
Showing 1 changed file with 212 additions and 9 deletions.
221 changes: 212 additions & 9 deletions app/os_macos.m
View file
Original file line number Diff line number Diff line change
Expand Up @@ -69,6 +69,212 @@ static void handleMouse(GioView *view, NSEvent *event, int typ, CGFloat dx, CGFl
gio_onMouse(view.handle, (__bridge CFTypeRef)event, typ, event.buttonNumber, p.x, height - p.y, dx, dy, [event timestamp], [event modifierFlags]);
}

@interface GioApplication: NSApplication
@end

// Variables for tracking resizes.
static struct {
NSPoint dir;
NSEvent *lastMouseDown;
NSPoint off;
} resizeState = {};

static NSBitmapImageRep *nsImageBitmap(NSImage *img) {
NSArray<NSImageRep *> *reps = img.representations;
if ([reps count] == 0) {
return nil;
}
NSImageRep *rep = reps[0];
if (![rep isKindOfClass:[NSBitmapImageRep class]]) {
return nil;
}
return (NSBitmapImageRep *)rep;
}

static NSCursor *lookupPrivateNSCursor(SEL name) {
if (![NSCursor respondsToSelector:name]) {
return nil;
}
id obj = [NSCursor performSelector:name];
if (![obj isKindOfClass:[NSCursor class]]) {
return nil;
}
return (NSCursor *)obj;
}

static BOOL isEqualNSCursor(NSCursor *c1, SEL name2) {
NSCursor *c2 = lookupPrivateNSCursor(name2);
if (c2 == nil || !NSEqualPoints(c1.hotSpot, c2.hotSpot)) {
return NO;
}
NSImage *img1 = c1.image;
NSImage *img2 = c2.image;
if (!NSEqualSizes(img1.size, img2.size)) {
return NO;
}
NSBitmapImageRep *bit1 = nsImageBitmap(img1);
NSBitmapImageRep *bit2 = nsImageBitmap(img2);
if (bit1 == nil || bit2 == nil) {
return NO;
}
NSInteger n1 = bit1.numberOfPlanes*bit1.bytesPerPlane;
NSInteger n2 = bit1.numberOfPlanes*bit1.bytesPerPlane;
if (n1 != n2) {
return NO;
}
if (memcmp(bit1.bitmapData, bit2.bitmapData, n1) != 0) {
return NO;
}
return YES;
}

@implementation GioApplication
- (NSEvent *)nextEventMatchingMask:(NSEventMask)mask
untilDate:(NSDate *)expiration
inMode:(NSRunLoopMode)mode
dequeue:(BOOL)deqFlag {
if ([mode isEqualToString:NSEventTrackingRunLoopMode]) {
NSEvent *l = resizeState.lastMouseDown;
if (l != nil) {
//lastMouseDown = nil;
NSCursor *cur = [NSCursor currentSystemCursor];
NSPoint dir = {};
NSPoint off = {};
NSSize wsz = [l window].frame.size;
NSPoint center = NSMakePoint(wsz.width/2, wsz.height/2);
NSPoint p = [l locationInWindow];
if (p.x >= center.x) {
dir.x = 1;
off.x = p.x - wsz.width;
} else {
dir.x = -1;
off.x = p.x;
}
if (p.y >= center.y) {
dir.y = 1;
off.y = p.y - wsz.height;
} else {
dir.y = -1;
off.y = p.y;
}
// The button down coordinate distinguish the four quadrants. Use the
// cursor image to determine the precise direction.
SEL nw = @selector(_windowResizeNorthWestCursor);
SEL n = @selector(_windowResizeNorthCursor);
SEL ne = @selector(_windowResizeNorthEastCursor);
SEL e = @selector(_windowResizeEastCursor);
SEL se = @selector(_windowResizeSouthEastCursor);
SEL s = @selector(_windowResizeSouthCursor);
SEL sw = @selector(_windowResizeSouthWestCursor);
SEL w = @selector(_windowResizeWestCursor);
SEL ns = @selector(_windowResizeNorthSouthCursor);
SEL ew = @selector(_windowResizeEastWestCursor);
SEL nwse = @selector(_windowResizeNorthWestSouthEastCursor);
SEL nesw = @selector(_windowResizeNorthEastSouthWestCursor);
BOOL match = YES;
if (dir.x != 0 && (isEqualNSCursor(cur, ew) || isEqualNSCursor(cur, w) || isEqualNSCursor(cur, e))) {
dir.y = 0;
}
if (dir.y != 0 && (isEqualNSCursor(cur, ns) || isEqualNSCursor(cur, s) || isEqualNSCursor(cur, n))) {
dir.x = 0;
}
// If none of the cursors matched, we may deduce that the resize
// direction is one of the corners. However, to ensure that at least
// one cursor matches, check the corner cursors.
if (dir.x == 1 && dir.y == 1) {
if (!isEqualNSCursor(cur, nesw) && !isEqualNSCursor(cur, sw)) {
dir = NSZeroPoint;
}
} else if (dir.x == 1 && dir.y == -1) {
if (!isEqualNSCursor(cur, nwse) && !isEqualNSCursor(cur, nw)) {
dir = NSZeroPoint;
}
} else if (dir.x == -1 && dir.y == 1) {
if (!isEqualNSCursor(cur, nwse) && !isEqualNSCursor(cur, se)) {
dir = NSZeroPoint;
}
} else if (dir.x == -1 && dir.y == -1) {
if (!isEqualNSCursor(cur, nesw) && !isEqualNSCursor(cur, ne)) {
dir = NSZeroPoint;
}
}
if (!NSEqualPoints(dir, NSZeroPoint)) {
NSEvent *cancel = [NSEvent mouseEventWithType:NSEventTypeLeftMouseUp
location:l.locationInWindow
modifierFlags:l.modifierFlags
timestamp:l.timestamp
windowNumber:l.windowNumber
context:l.context
eventNumber:l.eventNumber
clickCount:l.clickCount
pressure:l.pressure];
resizeState.off = off;
resizeState.dir = dir;
return cancel;
}
}
}
return [super nextEventMatchingMask:mask untilDate:expiration inMode:mode dequeue:deqFlag];
}
@end

@interface GioWindow: NSWindow
@end

@implementation GioWindow
- (void)sendEvent:(NSEvent *)evt {
if (evt.type == NSEventTypeLeftMouseDown) {
resizeState.lastMouseDown = evt;
}
NSPoint dir = resizeState.dir;
if (NSEqualPoints(dir, NSZeroPoint)) {
[super sendEvent:evt];
return;
}
switch (evt.type) {
default:
return;
case NSEventTypeLeftMouseUp:
resizeState.dir = NSZeroPoint;
resizeState.lastMouseDown = nil;
return;
case NSEventTypeLeftMouseDragged:
// Ok to proceed.
break;
}
NSPoint loc = evt.locationInWindow;
NSPoint off = resizeState.off;
loc.x -= off.x;
loc.y -= off.y;
NSRect frame = [self frame];
NSSize min = [self minSize];
NSSize max = [self maxSize];
CGFloat width = frame.size.width;
if (dir.x > 0) {
width = loc.x;
} else if (dir.x < 0) {
width -= loc.x;
}
width = MIN(max.width, MAX(min.width, width));
if (dir.x < 0) {
frame.origin.x += frame.size.width - width;
}
frame.size.width = width;
CGFloat height = frame.size.height;
if (dir.y > 0) {
height = loc.y;
} else if (dir.y < 0) {
height -= loc.y;
}
height = MIN(max.height, MAX(min.height, height));
if (dir.y < 0) {
frame.origin.y += frame.size.height - height;
}
frame.size.height = height;
[self setFrame:frame display:YES animate:NO];
}
@end

@implementation GioView
- (void)setFrameSize:(NSSize)newSize {
[super setFrameSize:newSize];
Expand Down Expand Up @@ -255,14 +461,11 @@ void gio_showCursor() {
// some cursors are not public, this tries to use a private cursor
// and uses fallback when the use of private cursor fails.
static void trySetPrivateCursor(SEL cursorName, NSCursor* fallback) {
if ([NSCursor respondsToSelector:cursorName]) {
id object = [NSCursor performSelector:cursorName];
if ([object isKindOfClass:[NSCursor class]]) {
[(NSCursor*)object set];
return;
}
NSCursor *cur = lookupPrivateNSCursor(cursorName);
if (cur == nil) {
cur = fallback;
}
[fallback set];
[cur set];
}

void gio_setCursor(NSUInteger curID) {
Expand Down Expand Up @@ -361,7 +564,7 @@ CFTypeRef gio_createWindow(CFTypeRef viewRef, CGFloat width, CGFloat height, CGF
NSMiniaturizableWindowMask |
NSClosableWindowMask;

NSWindow* window = [[NSWindow alloc] initWithContentRect:rect
GioWindow* window = [[GioWindow alloc] initWithContentRect:rect
styleMask:styleMask
backing:NSBackingStoreBuffered
defer:NO];
Expand Down Expand Up @@ -416,7 +619,7 @@ - (void)applicationDidFinishLaunching:(NSNotification *)aNotification {

void gio_main() {
@autoreleasepool {
[NSApplication sharedApplication];
[GioApplication sharedApplication];
GioAppDelegate *del = [[GioAppDelegate alloc] init];
[NSApp setDelegate:del];

Expand Down

0 comments on commit 768e597

Please sign in to comment.