alchemy-docs/field__coordinate_8h_source.html

#ifndef ALCHEMY_FIELD_COORDINATE_H

#define ALCHEMY_FIELD_COORDINATE_H


/// @file

/// FieldCoordinate, a position on the field.


#include "types.h"

#include "static_assert.h"


/// A field coordinate, read whole or as its fraction and its whole pixels.

union FieldCoordinate {

  s32 fixed; ///< 16.16 fixed-point pixels

  struct {

    u16 fraction; ///< 1/65536 pixels

    s16 pixel;    ///< pixels

  } part;

};


STATIC_ASSERT(sizeof(union FieldCoordinate) == 4);

STATIC_ASSERT(offsetof(union FieldCoordinate, part.pixel) == 2);


#endif

static_assert.h
STATIC_ASSERT, a compile-time check that emits nothing.

STATIC_ASSERT
#define STATIC_ASSERT(condition)
C89 permits repeated extern declarations of the same array.
Definition static_assert.h:15

offsetof
#define offsetof(type, member)
Definition stddef.h:19

FieldCoordinate::[struct].part::pixel
s16 pixel
pixels

FieldCoordinate::[struct].part::fraction
u16 fraction
1/65536 pixels

types.h
The integer types, TRUE, UNUSED and the fixed-address macros.

s32
signed int s32
Definition types.h:14

s16
signed short s16
Definition types.h:12

u16
unsigned short u16
Definition types.h:13

FieldCoordinate
A field coordinate, read whole or as its fraction and its whole pixels.
Definition field_coordinate.h:11

FieldCoordinate::part
struct FieldCoordinate::@024321007066302143002254325121164243234242211074 part

FieldCoordinate::fixed
s32 fixed
16.16 fixed-point pixels
Definition field_coordinate.h:12