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src/java.desktop/share/native/libfreetype/src/base/ftcalc.c
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@@ -1,37 +1,37 @@
-/***************************************************************************/
-/* */
-/* ftcalc.c */
-/* */
-/* Arithmetic computations (body). */
-/* */
-/* Copyright 1996-2018 by */
-/* David Turner, Robert Wilhelm, and Werner Lemberg. */
-/* */
-/* This file is part of the FreeType project, and may only be used, */
-/* modified, and distributed under the terms of the FreeType project */
-/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
-/* this file you indicate that you have read the license and */
-/* understand and accept it fully. */
-/* */
-/***************************************************************************/
-
- /*************************************************************************/
- /* */
- /* Support for 1-complement arithmetic has been totally dropped in this */
- /* release. You can still write your own code if you need it. */
- /* */
- /*************************************************************************/
+/****************************************************************************
+ *
+ * ftcalc.c
+ *
+ * Arithmetic computations (body).
+ *
+ * Copyright (C) 1996-2019 by
+ * David Turner, Robert Wilhelm, and Werner Lemberg.
+ *
+ * This file is part of the FreeType project, and may only be used,
+ * modified, and distributed under the terms of the FreeType project
+ * license, LICENSE.TXT. By continuing to use, modify, or distribute
+ * this file you indicate that you have read the license and
+ * understand and accept it fully.
+ *
+ */
- /*************************************************************************/
- /* */
- /* Implementing basic computation routines. */
- /* */
- /* FT_MulDiv(), FT_MulFix(), FT_DivFix(), FT_RoundFix(), FT_CeilFix(), */
- /* and FT_FloorFix() are declared in freetype.h. */
- /* */
- /*************************************************************************/
+ /**************************************************************************
+ *
+ * Support for 1-complement arithmetic has been totally dropped in this
+ * release. You can still write your own code if you need it.
+ *
+ */
+
+ /**************************************************************************
+ *
+ * Implementing basic computation routines.
+ *
+ * FT_MulDiv(), FT_MulFix(), FT_DivFix(), FT_RoundFix(), FT_CeilFix(),
+ * and FT_FloorFix() are declared in freetype.h.
+ *
+ */
#include <ft2build.h>
#include FT_GLYPH_H
#include FT_TRIGONOMETRY_H
@@ -56,18 +56,18 @@
} FT_Int64;
#endif /* !FT_LONG64 */
- /*************************************************************************/
- /* */
- /* The macro FT_COMPONENT is used in trace mode. It is an implicit */
- /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */
- /* messages during execution. */
- /* */
+ /**************************************************************************
+ *
+ * The macro FT_COMPONENT is used in trace mode. It is an implicit
+ * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log
+ * messages during execution.
+ */
#undef FT_COMPONENT
-#define FT_COMPONENT trace_calc
+#define FT_COMPONENT calc
/* transfer sign, leaving a positive number; */
/* we need an unsigned value to safely negate INT_MIN (or LONG_MIN) */
#define FT_MOVE_SIGN( x, x_unsigned, s ) \
@@ -699,12 +699,12 @@
FT_MulFix( matrix->xy, matrix->yx );
if ( !delta )
return FT_THROW( Invalid_Argument ); /* matrix can't be inverted */
- matrix->xy = - FT_DivFix( matrix->xy, delta );
- matrix->yx = - FT_DivFix( matrix->yx, delta );
+ matrix->xy = -FT_DivFix( matrix->xy, delta );
+ matrix->yx = -FT_DivFix( matrix->yx, delta );
xx = matrix->xx;
yy = matrix->yy;
matrix->xx = FT_DivFix( yy, delta );
@@ -745,10 +745,80 @@
}
/* documentation is in ftcalc.h */
+ FT_BASE_DEF( FT_Bool )
+ FT_Matrix_Check( const FT_Matrix* matrix )
+ {
+ FT_Matrix m;
+ FT_Fixed val[4];
+ FT_Fixed nonzero_minval, maxval;
+ FT_Fixed temp1, temp2;
+ FT_UInt i;
+
+
+ if ( !matrix )
+ return 0;
+
+ val[0] = FT_ABS( matrix->xx );
+ val[1] = FT_ABS( matrix->xy );
+ val[2] = FT_ABS( matrix->yx );
+ val[3] = FT_ABS( matrix->yy );
+
+ /*
+ * To avoid overflow, we ensure that each value is not larger than
+ *
+ * int(sqrt(2^31 / 4)) = 23170 ;
+ *
+ * we also check that no value becomes zero if we have to scale.
+ */
+
+ maxval = 0;
+ nonzero_minval = FT_LONG_MAX;
+
+ for ( i = 0; i < 4; i++ )
+ {
+ if ( val[i] > maxval )
+ maxval = val[i];
+ if ( val[i] && val[i] < nonzero_minval )
+ nonzero_minval = val[i];
+ }
+
+ /* we only handle 32bit values */
+ if ( maxval > 0x7FFFFFFFL )
+ return 0;
+
+ if ( maxval > 23170 )
+ {
+ FT_Fixed scale = FT_DivFix( maxval, 23170 );
+
+
+ if ( !FT_DivFix( nonzero_minval, scale ) )
+ return 0; /* value range too large */
+
+ m.xx = FT_DivFix( matrix->xx, scale );
+ m.xy = FT_DivFix( matrix->xy, scale );
+ m.yx = FT_DivFix( matrix->yx, scale );
+ m.yy = FT_DivFix( matrix->yy, scale );
+ }
+ else
+ m = *matrix;
+
+ temp1 = FT_ABS( m.xx * m.yy - m.xy * m.yx );
+ temp2 = m.xx * m.xx + m.xy * m.xy + m.yx * m.yx + m.yy * m.yy;
+
+ if ( temp1 == 0 ||
+ temp2 / temp1 > 50 )
+ return 0;
+
+ return 1;
+ }
+
+
+ /* documentation is in ftcalc.h */
+
FT_BASE_DEF( void )
FT_Vector_Transform_Scaled( FT_Vector* vector,
const FT_Matrix* matrix,
FT_Long scaling )
{
@@ -911,24 +981,26 @@
ft_corner_orientation( FT_Pos in_x,
FT_Pos in_y,
FT_Pos out_x,
FT_Pos out_y )
{
+ /* we silently ignore overflow errors since such large values */
+ /* lead to even more (harmless) rendering errors later on */
+
#ifdef FT_LONG64
- FT_Int64 delta = (FT_Int64)in_x * out_y - (FT_Int64)in_y * out_x;
+ FT_Int64 delta = SUB_INT64( MUL_INT64( in_x, out_y ),
+ MUL_INT64( in_y, out_x ) );
return ( delta > 0 ) - ( delta < 0 );
#else
FT_Int result;
- /* we silently ignore overflow errors, since such large values */
- /* lead to even more (harmless) rendering errors later on */
if ( ADD_LONG( FT_ABS( in_x ), FT_ABS( out_y ) ) <= 131071L &&
ADD_LONG( FT_ABS( in_y ), FT_ABS( out_x ) ) <= 131071L )
{
FT_Long z1 = MUL_LONG( in_x, out_y );
FT_Long z2 = MUL_LONG( in_y, out_x );
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