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hash.h
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22 
23 
24 #ifndef _GUAC_HASH_H
25 #define _GUAC_HASH_H
26 
34 #include <cairo/cairo.h>
35 
46 unsigned int guac_hash_surface(cairo_surface_t* surface);
47 
59 int guac_surface_cmp(cairo_surface_t* a, cairo_surface_t* b);
60 
61 #endif
62 
int guac_surface_cmp(cairo_surface_t *a, cairo_surface_t *b)
Given two Cairo surfaces, returns zero if the data contained within each is identical, and a positive or negative value if the value of the first is found to be lexically greater or less than the second respectively.
unsigned int guac_hash_surface(cairo_surface_t *surface)
Produces a 24-bit hash value from all pixels of the given surface.