macOS Looking for a guide on Cocoa graphics

[monsieurpaul]

Hello,

I am starting to be really confused with Image, ImageRep, View, GraphicsContext, etc.

On one hand, what I have found in books and blogs focuses mainly on recipes. On the other hand, I am finding the Cocoa Drawing Guide from Apple documentation really overwhelming.

Does anyone has something else to recommend ?

Thanks,
Paul

 

[jiminaus]

I've not read it, but I'v heard of Scott Thompson, R. (2006) Quartz 2D graphics for Mac OS X developers.

 

[mfram]

I was able to get an image displayed based on a bitmap my program computed. The code looked something like this (paraphrasing)...

        NSBitmapImageRep *myBitmap;
        NSImage *myImage;
        unsigned char *buff[4];
        unsigned char *pixels;

        pixels = malloc(rectSize * 4);

        for(y = 0; y < height; y++)
        {
                for(x = 0; x < width; x++)
                {
                        // do stuff
                        pixels[i++] = red;
                        pixels[i++] = green;
                        pixels[i++] = blue;
                        pixels[i++] = 255;   // Alpha channel
                }
        }

        buff[0] = pixels;

        myBitmap = [[NSBitmapImageRep alloc]
                  initWithBitmapDataPlanes:buff 
                  pixelsWide:width
                  pixelsHigh:height
                  bitsPerSample:8
                  samplesPerPixel:4
                  hasAlpha:YES
                  isPlanar:NO
                  colorSpaceName:NSCalibratedRGBColorSpace
                  bitmapFormat:0
                  bytesPerRow:(4 * width)
                  bitsPerPixel:32];

        myImage = [[NSImage alloc] init];
        [myImage addRepresentation:myBitmap];
        [display setImage: myImage];
        [myImage release];
        [myBitmap release];
}

Where "display" is an outlet to a View which contains an image.

 

[mif]

mfram, can i use that code?

 

[mfram]

Yes, you may use the code. Try it out.

 

[mif]

Thanks. it may get me started learning Cocoa.