darling-cocotron/AppKit/NSCursor.m

/* Copyright (c) 2006-2007 Christopher J. W. Lloyd

Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */

#import <AppKit/NSCursor.h>
#import <AppKit/NSDisplay.h>
#import <AppKit/NSGraphicsContext.h>
#import <AppKit/NSImage.h>
#import <AppKit/NSRaise.h>
#import <Foundation/NSNull.h>
#ifdef WINDOWS
#import <AppKit/Win32Cursor.h>
#import <Foundation/NSPlatform_win32.h>
#import <windows.h>
#endif

id NSPlatformCreateCursorImpWithName(NSString *name) {
    return [[[NSDisplay currentDisplay] cursorWithName: name] retain];
}

id NSPlatformCreateCursorImpWithImage(NSImage *image, NSPoint hotSpot) {
#ifndef WINDOWS
    return [[[NSDisplay currentDisplay] cursorWithImage: image
                                                hotSpot: hotSpot] retain];
#else
    /// move to the platform files
    size_t width = [image size].width;
    size_t height = [image size].height;

    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
    CGContextRef context = CGBitmapContextCreate(
            NULL, width, height, 8, 0, colorSpace,
            kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Little);
    CGColorSpaceRelease(colorSpace);

    NSAutoreleasePool *pool = [NSAutoreleasePool new];
    NSGraphicsContext *graphicsContext =
            [NSGraphicsContext graphicsContextWithGraphicsPort: context
                                                       flipped: NO];

    [NSGraphicsContext saveGraphicsState];
    [NSGraphicsContext setCurrentContext: graphicsContext];

    [image drawInRect: NSMakeRect(0, 0, width, height)
             fromRect: NSZeroRect
            operation: NSCompositeCopy
             fraction: 1.0];

    [NSGraphicsContext restoreGraphicsState];

    [pool release];

    uint8_t *rowBytes = CGBitmapContextGetData(context);
    size_t bytesPerRow = CGBitmapContextGetBytesPerRow(context);

    HDC displayDC = GetDC(NULL);
    HBITMAP colorBitmap;
    HBITMAP maskBitmap;

    if (NSPlatformGreaterThanOrEqualToWindows2000()) {
        // Cursor with alpha channel, no mask. Win2k and above
        BITMAPV5HEADER bi;
        void *lpBits;
        uint8_t *dibRowBytes;

        ZeroMemory(&bi, sizeof(BITMAPV5HEADER));
        bi.bV5Size = sizeof(BITMAPV5HEADER);
        bi.bV5Width = width;
        bi.bV5Height = -height;
        bi.bV5Planes = 1;
        bi.bV5BitCount = 32;
        bi.bV5Compression = BI_BITFIELDS;
        bi.bV5RedMask = 0x00FF0000;
        bi.bV5GreenMask = 0x0000FF00;
        bi.bV5BlueMask = 0x000000FF;
        bi.bV5AlphaMask = 0xFF000000;

        colorBitmap = CreateDIBSection(displayDC, (BITMAPINFO *) &bi,
                                       DIB_RGB_COLORS, &lpBits, NULL, 0);
        dibRowBytes = lpBits;

        maskBitmap = CreateBitmap(width, height, 1, 1, NULL);
        int row, column;

        for (row = 0; row < height;
             row++, rowBytes += bytesPerRow, dibRowBytes += width * 4) {
            for (column = 0; column < width; column++) {
                dibRowBytes[column * 4] = rowBytes[column * 4];
                dibRowBytes[column * 4 + 1] = rowBytes[column * 4 + 1];
                dibRowBytes[column * 4 + 2] = rowBytes[column * 4 + 2];
                dibRowBytes[column * 4 + 3] = rowBytes[column * 4 + 3];
            }
        }

    } else {
        // This works for versions lower than 2k, not really needed, but here.
        HDC colorDC = CreateCompatibleDC(displayDC);
        HDC maskDC = CreateCompatibleDC(displayDC);

        colorBitmap = CreateCompatibleBitmap(displayDC, width, height);
        maskBitmap = CreateCompatibleBitmap(displayDC, width, height);

        HBITMAP oldColorBitmap = SelectObject(colorDC, colorBitmap);
        HBITMAP oldMaskBitmap = SelectObject(maskDC, maskBitmap);

        int row, column;

        for (row = 0; row < height; row++, rowBytes += bytesPerRow) {
            for (column = 0; column < width; column++) {
                uint8_t b = rowBytes[column * 4];
                uint8_t g = rowBytes[column * 4 + 1];
                uint8_t r = rowBytes[column * 4 + 2];
                uint8_t a = rowBytes[column * 4 + 3];

                if (a < 255) {
                    SetPixel(colorDC, column, row, RGB(r, g, b));
                    SetPixel(maskDC, column, row, RGB(255, 255, 255));
                } else {
                    SetPixel(colorDC, column, row, RGB(r, g, b));
                    SetPixel(maskDC, column, row, RGB(0, 0, 0));
                }
            }
        }
        SelectObject(colorDC, oldColorBitmap);
        SelectObject(maskDC, oldMaskBitmap);
        DeleteDC(colorDC);
        DeleteDC(maskDC);
    }

    ReleaseDC(NULL, displayDC);

    CGContextRelease(context);

    ICONINFO iconInfo;

    iconInfo.fIcon = FALSE;
    iconInfo.xHotspot = hotSpot.x;
    iconInfo.yHotspot = hotSpot.y;
    iconInfo.hbmMask = maskBitmap;
    iconInfo.hbmColor = colorBitmap;

    HCURSOR hCursor = CreateIconIndirect(&iconInfo);

    DeleteObject(colorBitmap);
    DeleteObject(maskBitmap);

    return [[Win32Cursor alloc] initWithHCURSOR: hCursor];
#endif
}

void NSPlatformReleaseCursorImp(id object) {
    [object release];
}

void NSPlatformSetCursorImp(id object) {
    [[NSDisplay currentDisplay] setCursor: object];
}

@implementation NSCursor

static NSMutableArray *_cursorStack = nil;

+ (void) initialize {
    if (self == [NSCursor class]) {
        _cursorStack = [[NSMutableArray alloc] init];
    }
}

+ (NSCursor *) currentCursor {
    return [[[_cursorStack lastObject] retain] autorelease];
}

+ (NSCursor *) currentSystemCursor {
    return [[[_cursorStack lastObject] retain] autorelease];
}

- initWithCoder: (NSCoder *) coder {
    [self dealloc];
    return [NSNull null];
}

- (void) encodeWithCoder: (NSCoder *) coder {
    NSUnimplementedMethod();
}

- initWithName: (NSString *) name {
    _platformCursor = NSPlatformCreateCursorImpWithName(name);
    return self;
}

+ (NSCursor *) arrowCursor {
    static NSCursor *shared = nil;

    if (shared == nil)
        shared = [[self alloc] initWithName: NSStringFromSelector(_cmd)];

    return shared;
}

+ (NSCursor *) closedHandCursor {
    static NSCursor *shared = nil;

    if (shared == nil)
        shared = [[self alloc] initWithName: NSStringFromSelector(_cmd)];

    return shared;
}

+ (NSCursor *) contextualMenuCursor {
    static NSCursor *shared = nil;

    if (shared == nil)
        shared = [[self alloc] initWithName: NSStringFromSelector(_cmd)];

    return shared;
}

+ (NSCursor *) crosshairCursor {
    static NSCursor *shared = nil;

    if (shared == nil)
        shared = [[self alloc] initWithName: NSStringFromSelector(_cmd)];

    return shared;
}

+ (NSCursor *) disappearingItemCursor {
    static NSCursor *shared = nil;

    if (shared == nil)
        shared = [[self alloc] initWithName: NSStringFromSelector(_cmd)];

    return shared;
}

+ (NSCursor *) IBeamCursor {
    static NSCursor *shared = nil;

    if (shared == nil)
        shared = [[self alloc] initWithName: NSStringFromSelector(_cmd)];

    return shared;
}

+ (NSCursor *) openHandCursor {
    static NSCursor *shared = nil;

    if (shared == nil)
        shared = [[self alloc] initWithName: NSStringFromSelector(_cmd)];

    return shared;
}

+ (NSCursor *) pointingHandCursor {
    static NSCursor *shared = nil;

    if (shared == nil)
        shared = [[self alloc] initWithName: NSStringFromSelector(_cmd)];

    return shared;
}

+ (NSCursor *) resizeDownCursor {
    static NSCursor *shared = nil;

    if (shared == nil)
        shared = [[self alloc] initWithName: NSStringFromSelector(_cmd)];

    return shared;
}

+ (NSCursor *) resizeLeftCursor {
    static NSCursor *shared = nil;

    if (shared == nil)
        shared = [[self alloc] initWithName: NSStringFromSelector(_cmd)];

    return shared;
}

+ (NSCursor *) resizeLeftRightCursor {
    static NSCursor *shared = nil;

    if (shared == nil)
        shared = [[self alloc] initWithName: NSStringFromSelector(_cmd)];

    return shared;
}

+ (NSCursor *) resizeRightCursor {
    static NSCursor *shared = nil;

    if (shared == nil)
        shared = [[self alloc] initWithName: NSStringFromSelector(_cmd)];

    return shared;
}

+ (NSCursor *) resizeUpCursor {
    static NSCursor *shared = nil;

    if (shared == nil)
        shared = [[self alloc] initWithName: NSStringFromSelector(_cmd)];

    return shared;
}

+ (NSCursor *) resizeUpDownCursor {
    static NSCursor *shared = nil;

    if (shared == nil)
        shared = [[self alloc] initWithName: NSStringFromSelector(_cmd)];

    return shared;
}

+ (NSCursor *) dragCopyCursor {
    static NSCursor *shared = nil;

    if (shared == nil)
        shared = [[self alloc] initWithName: NSStringFromSelector(_cmd)];

    return shared;
}

+ (NSCursor *) dragLinkCursor {
    static NSCursor *shared = nil;

    if (shared == nil)
        shared = [[self alloc] initWithName: NSStringFromSelector(_cmd)];

    return shared;
}

+ (NSCursor *) operationNotAllowedCursor {
    static NSCursor *shared = nil;

    if (shared == nil)
        shared = [[self alloc] initWithName: NSStringFromSelector(_cmd)];

    return shared;
}

+ (void) hide {
    [[NSDisplay currentDisplay] hideCursor];
}

+ (void) unhide {
    [[NSDisplay currentDisplay] unhideCursor];
}

+ (void) setHiddenUntilMouseMoves: (BOOL) flag {
    if (flag)
        [self hide];
    else
        [self unhide];
}

- initWithImage: (NSImage *) image
        foregroundColorHint: (NSColor *) foregroundHint
        backgroundColorHint: (NSColor *) backgroundHint
                    hotSpot: (NSPoint) hotSpot
{
    // the hints are unused per doc.s
    return [self initWithImage: image hotSpot: hotSpot];
}

- initWithImage: (NSImage *) image hotSpot: (NSPoint) hotSpot {
    _image = [image retain];
    _hotSpot = hotSpot;
    _platformCursor = NSPlatformCreateCursorImpWithImage(image, hotSpot);
    return self;
}

- (void) dealloc {
    [_image release];
    NSPlatformReleaseCursorImp(_platformCursor);
    [super dealloc];
}

- (NSImage *) image {
    return _image;
}

- (NSPoint) hotSpot {
    return _hotSpot;
}

- (BOOL) isSetOnMouseEntered {
    return _isSetOnMouseEntered;
}

- (BOOL) isSetOnMouseExited {
    return _isSetOnMouseExited;
}

- (void) setOnMouseEntered: (BOOL) value {
    _isSetOnMouseEntered = value;
}

- (void) setOnMouseExited: (BOOL) value {
    _isSetOnMouseExited = value;
}

- (void) mouseEntered: (NSEvent *) event {
    NSUnimplementedMethod();
}

- (void) mouseExited: (NSEvent *) event {
    NSUnimplementedMethod();
}

- (void) pop {
    [[self class] pop];
}

- (void) set {
    if ([_cursorStack count])
        [_cursorStack removeLastObject];

    [_cursorStack addObject: self];
    NSPlatformSetCursorImp(_platformCursor);
}

- (void) push {
    [_cursorStack addObject: self];
    NSPlatformSetCursorImp(_platformCursor);
}

+ (void) pop {
    if ([_cursorStack count] < 2)
        return;

    [_cursorStack removeLastObject];

    NSCursor *cursor = [_cursorStack lastObject];

    if (cursor == nil)
        cursor = [NSCursor arrowCursor];

    NSPlatformSetCursorImp(cursor->_platformCursor);
}

@end