iteration to cover the whole sky with right ascension, declination, angle

I am sure I get parts of the terminology wrong but if anyone can shed some light in the following:

I understand that for a given right ascension (RA) and declination (DEC), one has defined a ray (half-line) in the sky starting from the center of the earth towards infinity.

Now, if I also provide a angle, say d degrees around that ray, I have essentially defined a cone in the sky. My question is the following:

Which steps (RA_step and DEC_step) should I use in the following loop, as a function of d to ensure that I cover the entire sky and don't leave any patches anywhere?.

for (RA = 0 ; RA <= 360 ; RA += RA_step)
for (DEC = -90 ; DEC <= 90 ; DEC += DEC_step)
examine-cone(RA, DEC, d)

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Wouldn't it be easier if you use square sky patchs? –  Envite Dec 5 '13 at 13:33
@Envite I don't have a choice, the API I am given uses cones so I need to cover the sky with cones, not "pyramids". –  Marcus Junius Brutus Dec 5 '13 at 13:53