RINT()

#define RINT(x) rint(x)

This macro rounds its argument x to an integer value in floating point format. Use RINT() instead of rint().

ROUND()

#define ROUND(x) ((int) ((x) + 0.5))

This macro rounds its positive argument x to the nearest integer.

SIGNED_ROUND()

#define SIGNED_ROUND(x) ((int) RINT (x))

This macro rounds its argument x to the nearest integer.

SQR()

#define SQR(x) ((x) * (x))

This macro squares its argument x .

MAX255()

#define MAX255(a)  ((a) | (((a) & 256) - (((a) & 256) >> 8)))

This macro limits it argument a , an (0-511) int, to 255.

CLAMP0255()

#define CLAMP0255(a)  CLAMP(a,0,255)

This macro clamps its argument a , an int32-range int, between 0 and 255 inclusive.

SAFE_CLAMP()

#define SAFE_CLAMP(x, low, high)  ((x) > (low) ? (x) < (high) ? (x) : (high) : (low))

Ensures that x is between the limits set by low and high , even if x is NaN. If low is greater than high , or if either of them is NaN, the result is undefined.

Since: 2.10

gimp_deg_to_rad()

#define gimp_deg_to_rad(angle) ((angle) * (2.0 * G_PI) / 360.0)

This macro converts its argument angle from degree to radian.

gimp_rad_to_deg()

#define gimp_rad_to_deg(angle) ((angle) * 360.0 / (2.0 * G_PI))

This macro converts its argument angle from radian to degree.