#import "ImageData.h"// This structure aims to be used in an immutable way@implementationImageData{GLubyte*_data;int_width;int_height;}-(instancetype)initWithData:(GLubyte*)datawithWidth:(int)widthwithHeight:(int)height{self=[superinit];if(self){_data=data;_width=width;_height=height;}returnself;}-(void)dealloc{if(_data){free(_data);_data=nil;_width=0;_height=0;}}@end