61     colors->null_red = red;
 
   62     colors->null_grn = grn;
 
   63     colors->null_blu = blu;
 
   84     colors->undef_red = red;
 
   85     colors->undef_grn = grn;
 
   86     colors->undef_blu = blu;
 
   87     colors->undef_set = 1;
 
int G_is_c_null_value(const CELL *cellVal)
Returns 1 if cell is NULL, 0 otherwise. This will test if the value cell is the largest int...
int G_set_default_color(int red, int grn, int blu, struct Colors *colors)
Sets the default color (in colors) to r,g,b. This is the color for values which do not have an explic...
int G_set_null_value_color(int red, int grn, int blu, struct Colors *colors)
Sets the color (in colors) for the NULL-value to r,g,b. 
int G_add_d_raster_color_rule(const DCELL *val1, int r1, int g1, int b1, const DCELL *val2, int r2, int g2, int b2, struct Colors *colors)
Adds the floating-point rule (DCELL version) 
int G_set_color(CELL cat, int r, int g, int b, struct Colors *colors)
set a category color 
int G_set_d_color(DCELL val, int r, int g, int b, struct Colors *colors)
int G_is_d_null_value(const DCELL *dcellVal)
Returns 1 if dcell is NULL, 0 otherwise. This will test if the value dcell is a NaN. Same test as in G_is_f_null_value(). 
int G_add_color_rule(CELL cat1, int r1, int g1, int b1, CELL cat2, int r2, int g2, int b2, struct Colors *colors)
Set colors rules.