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/*

IMPORTANT NOTE: THIS CODE IS NOT SAFE ACROSS INTEL/PPC PROCCESSORS. I’LL BE POSTING AN ALTERNATIVE OPTION SOON.

Some samplecode that shows how to store a C array of floats (or any other kind with a little change to this code) in a keyed archive for Cocoa. I struggled quite a bit to get it right. I noticed there wasn’t many information about this to be found on the internet. I hope this’ll help someone out. :-)

*/



-(id)init {

    if (self = [super init]) {

        arrayOfFloats = (float *) malloc(1*sizeof(float));

        numberOfPoints = 1;

    }

    return self;

}



-(void)encodeWithCoder:(NSCoder *)coder {

    if ([coder allowsKeyedCoding]) { // Assuming 10.2 is quite safe!!

        [coder encodeInt:numberOfPoints forKey:@"numberOfPoints"];

        [coder encodeBytes:(void *)arrayOfFloats length:numberOfPoints*sizeof(float) forKey:@"arrayOfFloats"];

    }

    return;

}



- (id)initWithCoder:(NSCoder *)coder {

    if ([coder allowsKeyedCoding]) {

        numberOfPoints = [coder decodeIntForKey:@"numberOfPoints"];



        const uint8_t *temporary = NULL; // Pointer to a temporary buffer returned by the decoder

        unsigned int length; // Will hold the length of the returned bytes, not used here, as we separately encoded the length of the array

        arrayOfFloats = (float *) malloc(1*sizeof(float)); // since the accessor uses realloc, we need to malloc masses at least one time



        temporary = [coder decodeBytesForKey:@"arrayOfFloats" returnedLength:&length];

        [self setArrayOfFloats:temporary withCount:numberOfPoints];             

    }

    return self;

}



-(void)setArrayOfFloats:(float *)inArray withCount:(int)inValue {

    numberOfPoints = inValue;

    arrayOfFloats = (float *) realloc(arrayOfFloats, numberOfPoints*sizeof(float));

    memcpy(arrayOfFloats, inArray, numberOfPoints*sizeof(float));

}