engine: host: oops

Without this fix, data still might overflow after applying multiplier
and potentially send incorrect data.

engine/common/host.c

@@ -941,6 +941,7 @@ static void Host_RunTests( int stage )
 		TEST_LIST_1_CLIENT;
 #endif
 		Msg( "Done! %d passed, %d failed\n", tests_stats.passed, tests_stats.failed );
+		error_on_exit = tests_stats.failed > 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 		Sys_Quit();
 	}
 }

engine/common/net_encode.c

@@ -315,6 +315,43 @@ static const delta_field_t ent_fields[] =
 { NULL },
 };
 
+#if XASH_ENGINE_TESTS
+typedef struct delta_test_struct_t
+{
+	char     dt_string[128];    // always signed
+	float    dt_timewindow_big; // always signed
+	float    dt_timewindow_8;   // always signed
+	float	 dt_angle;          // always_signed
+	float    dt_float_signed;
+	float    dt_float_unsigned;
+	int32_t  dt_integer_signed;
+	uint32_t dt_integer_unsigned;
+	int16_t  dt_short_signed;
+	uint16_t dt_short_unsigned;
+	int8_t   dt_byte_signed;
+	uint8_t  dt_byte_unsigned;
+} delta_test_struct_t;
+
+#define TEST_DEF( x )	#x, offsetof( delta_test_struct_t, x ), sizeof( ((delta_test_struct_t *)0)->x )
+
+static const delta_field_t test_fields[] =
+{
+{ TEST_DEF( dt_string ) },
+{ TEST_DEF( dt_timewindow_big )},
+{ TEST_DEF( dt_timewindow_8 )},
+{ TEST_DEF( dt_angle ) },
+{ TEST_DEF( dt_float_signed ) },
+{ TEST_DEF( dt_float_unsigned ) },
+{ TEST_DEF( dt_integer_signed ) },
+{ TEST_DEF( dt_integer_unsigned ) },
+{ TEST_DEF( dt_short_signed ) },
+{ TEST_DEF( dt_short_unsigned ) },
+{ TEST_DEF( dt_byte_signed ) },
+{ TEST_DEF( dt_byte_unsigned ) },
+{ NULL },
+};
+#endif
+
 enum
 {
 	DT_EVENT_T = 0,
@@ -325,6 +362,10 @@ enum
 	DT_ENTITY_STATE_T,
 	DT_ENTITY_STATE_PLAYER_T,
 	DT_CUSTOM_ENTITY_STATE_T,
+#if XASH_ENGINE_TESTS
+	DT_DELTA_TEST_STRUCT_T,
+#endif
+	DT_STRUCT_COUNT
 };
 
 static delta_info_t dt_info[] =
@@ -337,7 +378,10 @@ static delta_info_t dt_info[] =
 [DT_ENTITY_STATE_T]	       = { "entity_state_t", ent_fields, NUM_FIELDS( ent_fields ) },
 [DT_ENTITY_STATE_PLAYER_T] = { "entity_state_player_t", ent_fields, NUM_FIELDS( ent_fields ) },
 [DT_CUSTOM_ENTITY_STATE_T] = { "custom_entity_state_t", ent_fields, NUM_FIELDS( ent_fields ) },
-{ NULL },
+#if XASH_ENGINE_TESTS
+[DT_DELTA_TEST_STRUCT_T]   = { "delta_test_struct_t", test_fields, NUM_FIELDS( test_fields ) },
+#endif
+[DT_STRUCT_COUNT]          = { NULL },
 };
 
 static delta_info_t *Delta_FindStruct( const char *name )
@@ -411,9 +455,7 @@ static void Delta_CustomEncode( delta_info_t *dt, const void *from, const void *
 		dt->pFields[i].bInactive = false;
 
 	if( dt->userCallback )
-	{
 		dt->userCallback( dt->pFields, from, to );
-	}
 }
 
 static delta_field_t *Delta_FindFieldInfo( const delta_field_t *pInfo, const char *fieldName )
@@ -974,14 +1016,14 @@ static qboolean Delta_CompareField( delta_t *pField, void *from, void *to, doubl
 			toF = *(uint8_t *)((int8_t *)to + pField->offset );
 		}
 
+		if( !Q_equal(pField->multiplier, 1.0f ))
+		{
+			fromF *= pField->multiplier;
+			toF *= pField->multiplier;
+		}
+
 		fromF = Delta_ClampIntegerField( pField, fromF, signbit, pField->bits );
 		toF = Delta_ClampIntegerField( pField, toF, signbit, pField->bits );
-
-		if( !Q_equal(pField->multiplier, 1.0f ))
-			fromF *= pField->multiplier;
-
-		if( !Q_equal( pField->multiplier, 1.0f ))
-			toF *= pField->multiplier;
 	}
 	else if( pField->flags & DT_SHORT )
 	{
@@ -996,14 +1038,14 @@ static qboolean Delta_CompareField( delta_t *pField, void *from, void *to, doubl
 			toF = *(uint16_t *)((int8_t *)to + pField->offset );
 		}
 
+		if( !Q_equal(pField->multiplier, 1.0f ))
+		{
+			fromF *= pField->multiplier;
+			toF *= pField->multiplier;
+		}
+
 		fromF = Delta_ClampIntegerField( pField, fromF, signbit, pField->bits );
 		toF = Delta_ClampIntegerField( pField, toF, signbit, pField->bits );
-
-		if( !Q_equal(pField->multiplier, 1.0f ))
-			fromF *= pField->multiplier;
-
-		if( !Q_equal( pField->multiplier, 1.0f ))
-			toF *= pField->multiplier;
 	}
 	else if( pField->flags & DT_INTEGER )
 	{
@@ -1017,14 +1059,15 @@ static qboolean Delta_CompareField( delta_t *pField, void *from, void *to, doubl
 			fromF = *(uint32_t *)((int8_t *)from + pField->offset );
 			toF = *(uint32_t *)((int8_t *)to + pField->offset );
 		}
-		fromF = Delta_ClampIntegerField( pField, fromF, signbit, pField->bits );
-		toF = Delta_ClampIntegerField( pField, toF, signbit, pField->bits );
 
 		if( !Q_equal(pField->multiplier, 1.0f ))
+		{
 			fromF *= pField->multiplier;
-
-		if( !Q_equal( pField->multiplier, 1.0f ))
 			toF *= pField->multiplier;
+		}
+
+		fromF = Delta_ClampIntegerField( pField, fromF, signbit, pField->bits );
+		toF = Delta_ClampIntegerField( pField, toF, signbit, pField->bits );
 	}
 	else if( pField->flags & ( DT_ANGLE|DT_FLOAT ))
 	{
@@ -1034,33 +1077,17 @@ static qboolean Delta_CompareField( delta_t *pField, void *from, void *to, doubl
 	}
 	else if( pField->flags & DT_TIMEWINDOW_8 )
 	{
-		val_a = Q_rint((*(float *)((byte *)from + pField->offset )) * 100.0f );
-		val_b = Q_rint((*(float *)((byte *)to + pField->offset )) * 100.0f );
-		val_a -= Q_rint(timebase * 100.0);
-		val_b -= Q_rint(timebase * 100.0);
-		fromF = FloatAsInt( val_a );
-		toF = FloatAsInt( val_b );
+		val_a = *(float *)((byte *)from + pField->offset );
+		val_b = *(float *)((byte *)to + pField->offset );
+		fromF = Q_rint(( timebase - val_a ) * 100.0 );
+		toF = Q_rint(( timebase - val_b ) * 100.0 );
 	}
 	else if( pField->flags & DT_TIMEWINDOW_BIG )
 	{
-		val_a = (*(float *)((byte *)from + pField->offset ));
-		val_b = (*(float *)((byte *)to + pField->offset ));
-
-		if( !Q_equal( pField->multiplier, 1.0f ))
-		{
-			val_a *= pField->multiplier;
-			val_b *= pField->multiplier;
-			val_a = (timebase * pField->multiplier) - val_a;
-			val_b = (timebase * pField->multiplier) - val_b;
-		}
-		else
-		{
-			val_a = timebase - val_a;
-			val_b = timebase - val_b;
-		}
-
-		fromF = FloatAsInt( val_a );
-		toF = FloatAsInt( val_b );
+		val_a = *(float *)((byte *)from + pField->offset );
+		val_b = *(float *)((byte *)to + pField->offset );
+		fromF = Q_rint(( timebase - val_a ) * pField->multiplier );
+		toF = Q_rint(( timebase - val_b ) * pField->multiplier );
 	}
 	else if( pField->flags & DT_STRING )
 	{
@@ -1144,6 +1171,7 @@ static qboolean Delta_WriteField( sizebuf_t *msg, delta_t *pField, void *from, v
 	int		signbit = FBitSet( pField->flags, DT_SIGNED ) ? 1 : 0;
 	float		flValue, flAngle;
 	uint		iValue;
+	int dt;
 	const char	*pStr;
 
 	if( Delta_CompareField( pField, from, to, timebase ))
@@ -1160,11 +1188,11 @@ static qboolean Delta_WriteField( sizebuf_t *msg, delta_t *pField, void *from, v
 			iValue = *(int8_t *)((int8_t *)to + pField->offset );
 		else
 			iValue = *(uint8_t *)((int8_t *)to + pField->offset );
-		iValue = Delta_ClampIntegerField( pField, iValue, signbit, pField->bits );
 
-		if( !Q_equal( pField->multiplier, 1.0 ) )
+		if( !Q_equal( pField->multiplier, 1.0 ))
 			iValue *= pField->multiplier;
 
+		iValue = Delta_ClampIntegerField( pField, iValue, signbit, pField->bits );
 		MSG_WriteBitLong( msg, iValue, pField->bits, signbit );
 	}
 	else if( pField->flags & DT_SHORT )
@@ -1173,11 +1201,11 @@ static qboolean Delta_WriteField( sizebuf_t *msg, delta_t *pField, void *from, v
 			iValue = *(int16_t *)((int8_t *)to + pField->offset );
 		else
 			iValue = *(uint16_t *)((int8_t *)to + pField->offset );
-		iValue = Delta_ClampIntegerField( pField, iValue, signbit, pField->bits );
 
-		if( !Q_equal( pField->multiplier, 1.0 ) )
+		if( !Q_equal( pField->multiplier, 1.0 ))
 			iValue *= pField->multiplier;
-	
+
+		iValue = Delta_ClampIntegerField( pField, iValue, signbit, pField->bits );
 		MSG_WriteBitLong( msg, iValue, pField->bits, signbit );
 	}
 	else if( pField->flags & DT_INTEGER )
@@ -1186,11 +1214,11 @@ static qboolean Delta_WriteField( sizebuf_t *msg, delta_t *pField, void *from, v
 			iValue = *(int32_t *)((int8_t *)to + pField->offset );
 		else
 			iValue = *(uint32_t *)((int8_t *)to + pField->offset );
-		iValue = Delta_ClampIntegerField( pField, iValue, signbit, pField->bits );
 
-		if( !Q_equal( pField->multiplier, 1.0 ) )
+		if( !Q_equal( pField->multiplier, 1.0 ))
 			iValue *= pField->multiplier;
 
+		iValue = Delta_ClampIntegerField( pField, iValue, signbit, pField->bits );
 		MSG_WriteBitLong( msg, iValue, pField->bits, signbit );
 	}
 	else if( pField->flags & DT_FLOAT )
@@ -1210,19 +1238,17 @@ static qboolean Delta_WriteField( sizebuf_t *msg, delta_t *pField, void *from, v
 	}
 	else if( pField->flags & DT_TIMEWINDOW_8 )
 	{
-		signbit = 1; // timewindow is always signed
 		flValue = *(float *)((byte *)to + pField->offset );
-		iValue = (int)Q_rint( timebase * 100.0 ) - (int)Q_rint( flValue * 100.0 );
-		iValue = Delta_ClampIntegerField( pField, iValue, signbit, pField->bits );
-		MSG_WriteBitLong( msg, iValue, pField->bits, signbit );
+		dt = Q_rint(( timebase - flValue ) * 100.0 );
+		dt = Delta_ClampIntegerField( pField, dt, 1, pField->bits );
+		MSG_WriteSBitLong( msg, dt, pField->bits );
 	}
 	else if( pField->flags & DT_TIMEWINDOW_BIG )
 	{
-		signbit = 1; // timewindow is always signed
 		flValue = *(float *)((byte *)to + pField->offset );
-		iValue = (int)Q_rint( timebase * pField->multiplier ) - (int)Q_rint( flValue * pField->multiplier );
-		iValue = Delta_ClampIntegerField( pField, iValue, signbit, pField->bits );
-		MSG_WriteBitLong( msg, iValue, pField->bits, signbit );
+		dt = Q_rint(( timebase - flValue ) * pField->multiplier );
+		dt = Delta_ClampIntegerField( pField, dt, 1, pField->bits );
+		MSG_WriteSBitLong( msg, dt, pField->bits );
 	}
 	else if( pField->flags & DT_STRING )
 	{
@@ -1306,9 +1332,12 @@ static qboolean Delta_ReadField( sizebuf_t *msg, delta_t *pField, void *from, vo
 	if( pField->flags & DT_BYTE )
 	{
 		iValue = MSG_ReadBitLong( msg, pField->bits, bSigned );
-		if( !Q_equal( pField->multiplier, 1.0 ) )
+		if( !Q_equal( pField->multiplier, 1.0 ))
 			iValue /= pField->multiplier;
 
+		if( !Q_equal( pField->post_multiplier, 1.0 ))
+			iValue *= pField->post_multiplier;
+
 		if( bSigned )
 			*(int8_t *)((uint8_t *)to + pField->offset ) = iValue;
 		else
@@ -1317,9 +1346,12 @@ static qboolean Delta_ReadField( sizebuf_t *msg, delta_t *pField, void *from, vo
 	else if( pField->flags & DT_SHORT )
 	{
 		iValue = MSG_ReadBitLong( msg, pField->bits, bSigned );
-		if( !Q_equal( pField->multiplier, 1.0 ) )
+		if( !Q_equal( pField->multiplier, 1.0 ))
 			iValue /= pField->multiplier;
 
+		if( !Q_equal( pField->post_multiplier, 1.0 ))
+			iValue *= pField->post_multiplier;
+
 		if( bSigned )
 			*(int16_t *)((uint8_t *)to + pField->offset ) = iValue;
 		else
@@ -1328,9 +1360,12 @@ static qboolean Delta_ReadField( sizebuf_t *msg, delta_t *pField, void *from, vo
 	else if( pField->flags & DT_INTEGER )
 	{
 		iValue = MSG_ReadBitLong( msg, pField->bits, bSigned );
-		if( !Q_equal( pField->multiplier, 1.0 ) )
+		if( !Q_equal( pField->multiplier, 1.0 ))
 			iValue /= pField->multiplier;
 
+		if( !Q_equal( pField->post_multiplier, 1.0 ))
+			iValue *= pField->post_multiplier;
+
 		if( bSigned )
 			*(int32_t *)((uint8_t *)to + pField->offset ) = iValue;
 		else
@@ -1344,11 +1379,11 @@ static qboolean Delta_ReadField( sizebuf_t *msg, delta_t *pField, void *from, vo
 		else
 			flValue = iValue;
 
-		if( !Q_equal( pField->multiplier, 1.0 ) )
-			flValue = flValue / pField->multiplier;
+		if( !Q_equal( pField->multiplier, 1.0 ))
+			flValue /= pField->multiplier;
 
-		if( !Q_equal( pField->post_multiplier, 1.0 ) )
-			flValue = flValue * pField->post_multiplier;
+		if( !Q_equal( pField->post_multiplier, 1.0 ))
+			flValue *= pField->post_multiplier;
 
 		*(float *)((byte *)to + pField->offset ) = flValue;
 	}
@@ -1370,7 +1405,7 @@ static qboolean Delta_ReadField( sizebuf_t *msg, delta_t *pField, void *from, vo
 		bSigned = true; // timewindow is always signed
 		iValue = MSG_ReadBitLong( msg, pField->bits, bSigned );
 
-		if( !Q_equal( pField->multiplier, 1.0 ) )
+		if( !Q_equal( pField->multiplier, 1.0 ))
 			flTime = ( timebase * pField->multiplier - (int)iValue ) / pField->multiplier;
 		else
 			flTime = timebase - (int)iValue;
@@ -2069,3 +2104,103 @@ void GAME_EXPORT Delta_UnsetFieldByIndex( delta_t *pFields, int fieldNumber )
 
 	dt->pFields[fieldNumber].bInactive = true;
 }
+
+#if XASH_ENGINE_TESTS
+#include "tests.h"
+
+void Test_RunDelta( void )
+{
+	delta_info_t *dt = &dt_info[DT_DELTA_TEST_STRUCT_T];
+	delta_test_struct_t from, to = { 0 };
+	delta_test_struct_t null = { 0 };
+	sizebuf_t msg;
+	int i;
+	char buffer[4096] = { 0 };
+	const double timebase = 123.123;
+
+	// a1ba: netbuffer bitmasks are initialized in netchan for some reason
+	// initialize it ourselves just in case
+	MSG_InitMasks();	// initialize bit-masks
+
+	Delta_AddField( dt, "dt_string", DT_STRING, 1, 1.0f, 1.0f );
+	Delta_AddField( dt, "dt_timewindow_big", DT_TIMEWINDOW_BIG, 24, 1000.f, 1.0f );
+	Delta_AddField( dt, "dt_timewindow_8", DT_TIMEWINDOW_8, 8, 1.0f, 1.0f );
+	Delta_AddField( dt, "dt_angle", DT_ANGLE, 16, 1.0f, 1.0f );
+	Delta_AddField( dt, "dt_float_signed", DT_FLOAT | DT_SIGNED, 22, 100.0f, 1.0f );
+	Delta_AddField( dt, "dt_float_unsigned", DT_FLOAT, 24, 10000.0f, 0.1f );
+	Delta_AddField( dt, "dt_integer_signed", DT_INTEGER | DT_SIGNED, 24, 1.0f, 1.0f );
+	Delta_AddField( dt, "dt_integer_unsigned", DT_INTEGER, 24, 1.0f, 1.0f );
+	Delta_AddField( dt, "dt_short_signed", DT_SHORT | DT_SIGNED, 16, 1.0f, 1.0f );
+	Delta_AddField( dt, "dt_short_unsigned", DT_SHORT, 15, 0.125f, 1.0f );
+	Delta_AddField( dt, "dt_byte_signed", DT_BYTE | DT_SIGNED, 6, 1.0f, 1.0f );
+	Delta_AddField( dt, "dt_byte_unsigned", DT_BYTE, 8, 1.0f, 1.0f );
+
+	Q_strncpy( from.dt_string, "test data check it's the same", sizeof( from.dt_string ));
+	from.dt_timewindow_big = timebase + 2.3456;
+	from.dt_timewindow_8 = timebase + 0.0234;
+	from.dt_angle = 160.245f;
+	from.dt_float_signed = -15.123f;
+	from.dt_float_unsigned = 1235.321f;
+	from.dt_integer_signed = -412784;
+	from.dt_integer_unsigned = 123453;
+	from.dt_short_signed = -12343;
+	from.dt_short_unsigned = 32131;
+	from.dt_byte_signed = 16;
+	from.dt_byte_unsigned = 218;
+
+	MSG_Init( &msg, "test message", buffer, sizeof( buffer ));
+
+	for( i = 0; i < dt->numFields; i++ )
+		Delta_WriteField( &msg, &dt->pFields[i], &null, &from, timebase );
+
+	MSG_SeekToBit( &msg, 0, SEEK_SET );
+
+	for( i = 0; i < dt->numFields; i++ )
+		Delta_ReadField( &msg, &dt->pFields[i], &null, &to, timebase );
+
+	Con_Printf( "struct as encoded to delta:\n" );
+	TASSERT_STR( from.dt_string, to.dt_string );
+
+	// the epsilon value is derived from multiplier value
+	TASSERT( Q_equal_e( from.dt_timewindow_big, to.dt_timewindow_big, 0.001f ));
+
+	// dt_timewindow_8 type has multiplier locked at 100.0f
+	TASSERT( Q_equal_e( from.dt_timewindow_8, to.dt_timewindow_8, 0.01f ));
+	TASSERT( Q_equal_e( from.dt_angle, to.dt_angle, 0.1f ));
+	TASSERT( Q_equal_e( from.dt_float_signed, to.dt_float_signed, 0.01f ));
+
+	// dt_float_unsigned has post-multiplier that doesn't affect network data
+	// and therefore should be reverted back when comparing
+	TASSERT( Q_equal_e( from.dt_float_unsigned, to.dt_float_unsigned * 10.f , 0.01f ));
+
+	TASSERT_EQi( from.dt_integer_signed, to.dt_integer_signed );
+	TASSERT_EQi( from.dt_integer_unsigned, to.dt_integer_unsigned );
+	TASSERT_EQi( from.dt_short_signed, to.dt_short_signed );
+	TASSERT(( from.dt_short_unsigned & ( 0xffff << 3 )) == to.dt_short_unsigned );
+	TASSERT_EQi( from.dt_byte_signed, to.dt_byte_signed );
+	TASSERT_EQi( from.dt_byte_unsigned, to.dt_byte_unsigned );
+
+	Con_Printf( "from.dt_timewindow_big = %f\n", from.dt_timewindow_big );
+	Con_Printf( "to.dt_timewindow_big   = %f\n", to.dt_timewindow_big );
+	Con_Printf( "from.dt_timewindow_8 = %f\n", from.dt_timewindow_8 );
+	Con_Printf( "to.dt_timewindow_8   = %f\n", to.dt_timewindow_8 );
+	Con_Printf( "from.dt_angle = %f\n", from.dt_angle );
+	Con_Printf( "to.dt_angle   = %f\n", to.dt_angle );
+	Con_Printf( "from.dt_float_signed = %f\n", from.dt_float_signed );
+	Con_Printf( "to.dt_float_signed   = %f\n", to.dt_float_signed );
+	Con_Printf( "from.dt_float_unsigned = %f\n", from.dt_float_unsigned );
+	Con_Printf( "to.dt_float_unsigned   = %f\n", to.dt_float_unsigned );
+	Con_Printf( "from.dt_integer_signed = %i\n", from.dt_integer_signed );
+	Con_Printf( "to.dt_integer_signed   = %i\n", to.dt_integer_signed );
+	Con_Printf( "from.dt_integer_unsigned = %i\n", from.dt_integer_unsigned );
+	Con_Printf( "to.dt_integer_unsigned   = %i\n", to.dt_integer_unsigned );
+	Con_Printf( "from.dt_short_signed = %i\n", from.dt_short_signed );
+	Con_Printf( "to.dt_short_signed   = %i\n", to.dt_short_signed );
+	Con_Printf( "from.dt_short_unsigned = %i\n", from.dt_short_unsigned );
+	Con_Printf( "to.dt_short_unsigned   = %i\n", to.dt_short_unsigned );
+	Con_Printf( "from.dt_byte_signed = %i\n", from.dt_byte_signed );
+	Con_Printf( "to.dt_byte_signed   = %i\n", to.dt_byte_signed );
+	Con_Printf( "from.dt_byte_unsigned = %i\n", from.dt_byte_unsigned );
+	Con_Printf( "to.dt_byte_unsigned   = %i\n", to.dt_byte_unsigned );
+}
+#endif // XASH_ENGINE_TESTS

engine/common/system.c

@@ -53,7 +53,7 @@ GNU General Public License for more details.
 #include "library.h"
 #include "whereami.h"
 
-static int error_on_exit = 0;	// arg for exit();
+int error_on_exit = 0;	// arg for exit();
 
 /*
 ================

engine/common/system.h

@@ -41,7 +41,7 @@ NOTE: never change this structure because all dll descriptions in xash code
 writes into struct by offsets not names
 ========================================================================
 */
-
+extern int error_on_exit;
 void Sys_Sleep( int msec );
 double Sys_DoubleTime( void );
 char *Sys_GetClipboardData( void );

engine/common/tests.h

@@ -39,13 +39,15 @@ void Test_RunCon( void );
 void Test_RunVOX( void );
 void Test_RunIPFilter( void );
 void Test_RunGamma( void );
+void Test_RunDelta( void );
 
 #define TEST_LIST_0 \
 	Test_RunLibCommon(); \
 	Test_RunCommon(); \
 	Test_RunCmd(); \
 	Test_RunCvar(); \
-	Test_RunIPFilter();
+	Test_RunIPFilter(); \
+	Test_RunDelta();
 
 #define TEST_LIST_0_CLIENT \
 	Test_RunCon(); \

public/xash3d_mathlib.h

@@ -73,7 +73,8 @@ GNU General Public License for more details.
 
 #define Q_min( a, b )	(((a) < (b)) ? (a) : (b))
 #define Q_max( a, b )	(((a) > (b)) ? (a) : (b))
-#define Q_equal( a, b ) (((a) > ((b) - EQUAL_EPSILON)) && ((a) < ((b) + EQUAL_EPSILON)))
+#define Q_equal_e( a, b, e ) (((a) > ((b) - (e))) && ((a) < ((b) + (e))))
+#define Q_equal( a, b ) Q_equal_e( a, b, EQUAL_EPSILON )
 #define Q_recip( a )	((float)(1.0f / (float)(a)))
 #define Q_floor( a )	((float)(int)(a))
 #define Q_ceil( a )		((float)(int)((a) + 1))