This is what I've already adopted in my projects, but imo should be built into the engine. Just a nicety.
#define GEN_NUM "num"
#define GEN_VECTOR "vector"
#define GEN_BOX "box"
#define GEN_COLOR "color"
#define GEN_CIRCLE "circle"
#define GEN_SPHERE "sphere"
#define GEN_SQUARE "square"
#define GEN_CUBE "cube"
#define FILTER_ALPHA "alpha"
#define FILTER_ANGULAR_BLUR "angular_blur"
#define FILTER_BLOOM "bloom"
#define FILTER_COLOR "color"
#define FILTER_DISPLACE "displace"
#define FILTER_DROP_SHADOW "drop_shadow"
#define FILTER_BLUR "blur"
#define FILTER_LAYER "layer"
#define FILTER_MOTION_BLUR "motion_blur"
#define FILTER_OUTLINE "outline"
#define FILTER_RADIAL_BLUR "radial_blur"
#define FILTER_RAYS "rays"
#define FILTER_RIPPLE "ripple"
#define FILTER_WAVE "wave"
