A collection of useful macros. More...

Defines
#define	sgeLock(surface)
	Lock a surface.
#define	sgeUnlock(surface)
	Unlock a surface.
#define	sgeBailOut(format, args...)
	Hard exit.
#define	sgeMalloc(target, type, amount)
	Allocate ram, fill with 0.
#define	sgeMallocNoInit(target, type, amount)
	Allocate ram, uninitialized.
#define	sgeRealloc(target, type, amount)
	Resize allocated ram.
#define	sgeNew(target, type) sgeMalloc(target,type,1);
	Create one object (aka struct)
#define	sgeFree(target)
	Free the object.
#define	sgeRandom(from, range) (from + (int) ((float)(range+1) * (rand() / (RAND_MAX + (float)from))))
	Get a random integer.
#define	sgeRandomFloat(from, range) (float) ((float)from + ((float)(range+1) * (rand() / (RAND_MAX + (float)from))))
	Get a random float.
#define	sgeByteSwap16(val) (val)
	swap byteorder on big endian, otherwise do nothing
#define	sgeByteSwap32(val) (val)
	swap byteorder on big endian, otherwise do nothing
#define	sgeRound(val) round(val)
	round a integer value, if there is no c lib function available
#define	MAX(x, y) ((x) > (y) ? (x) : (y))
	define MAX if not already there
#define	MIN(x, y) ((x) < (y) ? (x) : (y))
	define MIN if not already there
#define	MINMAX(value, lower, upper) MIN(MAX((value), (lower)), (upper))
	keep a number in a certain range

Detailed Description

A collection of useful macros.

Macros for common tasks such as memory management and cross platform C incompatibilities.

Define Documentation

#define MAX	(	x,
		y
	)	((x) > (y) ? (x) : (y))

define MAX if not already there

Parameters:

x	a number
y	the max limit of the number

Returns:: x if it is in range of y, otherwise y

Definition at line 349 of file sge.h.

#define MIN	(	x,
		y
	)	((x) < (y) ? (x) : (y))

define MIN if not already there

Parameters:

x	a number
y	the min limit of the number

Returns:: x if it is in range of y, otherwise y

Definition at line 359 of file sge.h.

#define MINMAX	(	value,
		lower,
		upper
	)	MIN(MAX((value), (lower)), (upper))

keep a number in a certain range

Parameters:

value	the number to keep in range
lower	the lower end of the range
upper	the upper end of the range

Returns:: a number ensured to be in range of lower and upper borders

Definition at line 369 of file sge.h.

#define sgeBailOut	(	format,
		args...
	)

Value:

do {\
                fprintf(stderr,(format),args); \
                exit(-1); \
        } while (0)

Hard exit.

Parameters:

format	printf format string
args	arguments for the format string

Exit out of the application without any cleanup.

You should use this only if there is a unresolvable situation

Definition at line 204 of file sge.h.

#define sgeByteSwap16 ( val ) (val)

swap byteorder on big endian, otherwise do nothing

Parameters:

val	a 16bit number

Returns:: a 16bit number in a unique endianess

Use this for example if you write 16 or 32 bit numbers into a binary file to ensure it reads the same value on little and big endian

Definition at line 314 of file sge.h.

#define sgeByteSwap32 ( val ) (val)

swap byteorder on big endian, otherwise do nothing

Parameters:

val	a 32bit number (depending on prefix)

Returns:: a 32bit number in a unique endianess

Use this for example if you write 16 or 32 bit numbers into a binary file to ensure it reads the same value on little and big endian

Definition at line 324 of file sge.h.

#define sgeFree ( target )

Value:

do {\
                free(target);\
                target=NULL;\
        } while(0)

Free the object.

Parameters:

target the pointer to the struct to free

Definition at line 281 of file sge.h.

#define sgeLock ( surface )

Value:

do {\
                if (SDL_MUSTLOCK(surface)) SDL_LockSurface(surface);\
        } while (0)

Lock a surface.

Parameters:

surface surface to lock

Lock a surface for drawing operations.

You should always use this before operating on pixel level on a surface. On most platforms your code will work without locking surfaces, but there are platforms where you will experience crashes.

Definition at line 178 of file sge.h.

#define sgeMalloc	(	target,
		type,
		amount
	)

Value:

do {\
                (target)=(type *)malloc((amount+1)*sizeof(type));\
                if ((target)==NULL) {\
                        sgeBailOut("could not allocate %d bytes of ram\n", (int)((amount)*sizeof(type)));\
                }\
                memset(target,0,((amount)*sizeof(type)));\
        } while (0)

Allocate ram, fill with 0.

Parameters:

target	the pointer to the struct to alloc
type	the struct type to alloc
amount	the number of sructs to alloc

Returns:: a pointer to the allocated and zero filled ram

Allocates ram for a structure and fills it with zeros.

MyStruct *obj;

sgeMalloc(obj, MyStruct, 1);

Definition at line 223 of file sge.h.

#define sgeMallocNoInit	(	target,
		type,
		amount
	)

Value:

do {\
                (target)=(type *)malloc((amount+1)*sizeof(type));\
                if ((target)==NULL) {\
                        sgeBailOut("could not allocate %d bytes of ram\n", (int)((amount)*sizeof(type)));\
                }\
        } while (0)

Allocate ram, uninitialized.

Parameters:

target	the pointer to the struct to alloc
type	the struct type to alloc
amount	the number of sructs to alloc

Returns:: a pointer to the allocated ram

Allocates ram for a structure

MyStruct *obj;

sgeMalloc(obj, MyStruct, 1);

Definition at line 245 of file sge.h.

#define sgeNew	(	target,
		type
	)	sgeMalloc(target,type,1);

Create one object (aka struct)

Parameters:

target	the pointer to the struct to alloc
type	the struct type to alloc

Returns:: a pointer with allocated and zero filled ram

Definition at line 274 of file sge.h.

#define sgeRandom	(	from,
		range
	)	(from + (int) ((float)(range+1) * (rand() / (RAND_MAX + (float)from))))

Get a random integer.

Parameters:

from	the base for the random
range	the range the random will be around from +/-

Returns:: a random integer

Definition at line 293 of file sge.h.

#define sgeRandomFloat	(	from,
		range
	)	(float) ((float)from + ((float)(range+1) * (rand() / (RAND_MAX + (float)from))))

Get a random float.

Parameters:

from	the base for the random
range	the range the random will be around from +/-

Returns:: a random float

Definition at line 302 of file sge.h.

#define sgeRealloc	(	target,
		type,
		amount
	)

Value:

do {\
                (target)=realloc((target),sizeof(type)*(amount+1));\
                if (target==NULL) {\
                        sgeBailOut("could not allocate %d bytes of ram\n", (int)((amount)*sizeof(type)));\
                }\
        } while (0)

Resize allocated ram.

Parameters:

target	the pointer to the struct to alloc
type	the struct type to alloc
amount	the number of sructs to alloc

Returns:: a pointer to the increased ram

Definition at line 260 of file sge.h.

#define sgeRound ( val ) round(val)

round a integer value, if there is no c lib function available

val a float value

Returns:: a int value rounded

Definition at line 339 of file sge.h.

#define sgeUnlock ( surface )

Value:

do {\
                if (SDL_MUSTLOCK(surface)) SDL_UnlockSurface(surface);\
        } while (0)

Unlock a surface.

Parameters:

surface surface to unlock

Unlock a surface, must be called after processing a locked surface.

Definition at line 189 of file sge.h.

Macros

Defines

Detailed Description

Define Documentation