Hello everyone,
I'm trying to understand how NSImageRep works, so I read the docs and came up
with this simple code that seems to... do something.
I'm confused about what's actually doing, I only see a big black block in my
custom view.
My intention is to make a 2x2 pixels image with different grayscale colors. For
example one pixel black, the other white, etc, so I can see if it actually
draws the array I'm passing in to NSImageRep.
I'm guessing that the 2x2 pixel image will scale to fit the entire view so I
will see the pixels as big squares in the view.
Here's the relevant code:
@implementation PixelsView
- (id)initWithFrame:(NSRect)frame {
self = [super initWithFrame:frame];
if (self) {
pixels = (unsigned char *)malloc(4*sizeof(*pixels));
aSimpleBitmap = [[NSBitmapImageRep alloc]
initWithBitmapDataPlanes:&pixels
pixelsWide:2
pixelsHigh:2
bitsPerSample:8
samplesPerPixel:1
hasAlpha:NO
isPlanar:NO
colorSpaceName:NSDeviceWhiteColorSpace
bytesPerRow:2
bitsPerPixel:8];
pixels[0] = 1;
pixels[1] = 0;
pixels[2] = 0;
pixels[3] = 0;
}
return self;
}
- (void)drawRect:(NSRect)dirtyRect {
NSRect bounds = [self bounds];
[NSGraphicsContext saveGraphicsState];
[aSimpleBitmap drawInRect:bounds];
[NSGraphicsContext restoreGraphicsState];
}
@end
The docs say that NSDeviceWhiteColorSpace has pure white at 1.0, so I'm
guessing that pixels[0] = 1 will set a white pixel, am I wrong?
Xcode is not throwing any errors, but the view is not displaying what I expect.
Since I don't fully understand bitmap images, is there anything obvious that
I'm missing?
Thanks in advance._______________________________________________
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