libguac  0.9.13-incubating
hash.h
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19 
20 
21 #ifndef _GUAC_HASH_H
22 #define _GUAC_HASH_H
23 
31 #include <cairo/cairo.h>
32 
43 unsigned int guac_hash_surface(cairo_surface_t* surface);
44 
56 int guac_surface_cmp(cairo_surface_t* a, cairo_surface_t* b);
57 
58 #endif
59 
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.