TT_Error Instance_Init( PInstance ins )
{
PExecution_Context exec;
TT_Error error;
PFace face = ins->face;
exec = ins->face->font->exec;
/* debugging instances have their own context */
ins->GS = Default_GraphicsState;
Context_Load( exec, ins );
exec->callTop = 0;
exec->top = 0;
exec->period = 64;
exec->phase = 0;
exec->threshold = 0;
exec->metrics.x_ppem = 0;
exec->metrics.y_ppem = 0;
exec->metrics.pointSize = 0;
exec->metrics.x_scale1 = 0;
exec->metrics.x_scale2 = 1;
exec->metrics.y_scale1 = 0;
exec->metrics.y_scale2 = 1;
exec->metrics.ppem = 0;
exec->metrics.scale1 = 0;
exec->metrics.scale2 = 1;
exec->metrics.ratio = 1 << 16;
exec->instruction_trap = FALSE;
exec->cvtSize = ins->cvtSize;
exec->cvt = ins->cvt;
exec->F_dot_P = 0x10000;
/* allow font program execution */
Set_CodeRange( exec,
TT_CodeRange_Font,
face->fontProgram,
face->fontPgmSize );
/* disable CVT and glyph programs coderange */
Clear_CodeRange( exec, TT_CodeRange_Cvt );
Clear_CodeRange( exec, TT_CodeRange_Glyph );
if ( face->fontPgmSize > 0 )
{
error = Goto_CodeRange( exec, TT_CodeRange_Font, 0 );
if ( error )
goto Fin;
error = RunIns( exec );
Unset_CodeRange(exec);
}
else
error = TT_Err_Ok;
Fin:
Context_Save( exec, ins );
ins->valid = FALSE;
return error;
}
TT_Error Instance_Reset( PInstance ins,
Bool debug )
{
TT_Error error;
Int i;
PFace face;
PExecution_Context exec;
if ( !ins )
return TT_Err_Invalid_Instance_Handle;
if ( ins->valid )
return TT_Err_Ok;
face = ins->face;
exec = face->font->exec;
if ( ins->metrics.x_ppem < 1 ||
ins->metrics.y_ppem < 1 )
return TT_Err_Invalid_PPem;
/* compute new transformation */
if ( ins->metrics.x_ppem >= ins->metrics.y_ppem )
{
ins->metrics.scale1 = ins->metrics.x_scale1;
ins->metrics.scale2 = ins->metrics.x_scale2;
ins->metrics.ppem = ins->metrics.x_ppem;
ins->metrics.x_ratio = 1 << 16;
ins->metrics.y_ratio = MulDiv_Round( ins->metrics.y_ppem,
0x10000,
ins->metrics.x_ppem );
}
else
{
ins->metrics.scale1 = ins->metrics.y_scale1;
ins->metrics.scale2 = ins->metrics.y_scale2;
ins->metrics.ppem = ins->metrics.y_ppem;
ins->metrics.x_ratio = MulDiv_Round( ins->metrics.x_ppem,
0x10000,
ins->metrics.y_ppem );
ins->metrics.y_ratio = 1 << 16;
}
/* Scale the cvt values to the new ppem. */
/* We use by default the y ppem to scale the CVT. */
for ( i = 0; i < ins->cvtSize; i++ )
ins->cvt[i] = MulDiv_Round( face->cvt[i],
ins->metrics.scale1,
ins->metrics.scale2 );
ins->GS = Default_GraphicsState;
/* get execution context and run prep program */
Context_Load( exec, ins );
Set_CodeRange( exec,
TT_CodeRange_Cvt,
face->cvtProgram,
face->cvtPgmSize );
Clear_CodeRange( exec, TT_CodeRange_Glyph );
for ( i = 0; i < exec->storeSize; i++ )
exec->storage[i] = 0;
exec->instruction_trap = FALSE;
exec->top = 0;
exec->callTop = 0;
/* All twilight points are originally zero */
for ( i = 0; i < exec->twilight.n_points; i++ )
{
exec->twilight.org_x[i] = 0;
exec->twilight.org_y[i] = 0;
exec->twilight.cur_x[i] = 0;
exec->twilight.cur_y[i] = 0;
}
if ( face->cvtPgmSize > 0 )
{
error = Goto_CodeRange( exec, TT_CodeRange_Cvt, 0 );
if (error)
goto Fin;
error = RunIns( exec );
Unset_CodeRange(exec);
}
else
error = TT_Err_Ok;
ins->GS = exec->GS;
/* save default graphics state */
Fin:
Context_Save( exec, ins );
if ( !error )
ins->valid = TRUE;
return error;
}
Load_TrueType_Glyph( PInstance instance,
PGlyph glyph,
UShort glyph_index,
UShort load_flags )
{
enum TPhases_
{
Load_Exit,
Load_Glyph,
Load_Header,
Load_Simple,
Load_Composite,
Load_End
};
typedef enum TPhases_ TPhases;
DEFINE_ALL_LOCALS;
PFace face;
UShort num_points;
Short num_contours;
UShort left_points;
Short left_contours;
UShort num_elem_points;
Long table;
UShort load_top;
Long k, l;
UShort new_flags;
Long index;
UShort u, v;
Long glyph_offset, offset;
TT_F26Dot6 x, y, nx, ny;
Fixed xx, xy, yx, yy;
PExecution_Context exec;
PSubglyph_Record subglyph, subglyph2;
TGlyph_Zone base_pts;
TPhases phase;
PByte widths;
/* TT_Glyph_Loader_Callback cacheCb; */
/* TT_Outline cached_outline; */
/* first of all, check arguments */
if ( !glyph )
return TT_Err_Invalid_Glyph_Handle;
face = glyph->face;
if ( !face )
return TT_Err_Invalid_Glyph_Handle;
if ( glyph_index >= face->numGlyphs )
return TT_Err_Invalid_Glyph_Index;
if ( instance && (load_flags & TTLOAD_SCALE_GLYPH) == 0 )
{
instance = 0;
load_flags &= ~( TTLOAD_SCALE_GLYPH | TTLOAD_HINT_GLYPH );
}
table = TT_LookUp_Table( face, TTAG_glyf );
if ( table < 0 )
{
PTRACE0(( "ERROR: There is no glyph table in this font file!\n" ));
return TT_Err_Glyf_Table_Missing;
}
glyph_offset = face->dirTables[table].Offset;
/* query new execution context */
if ( instance && instance->debug )
exec = instance->context;
else
exec = New_Context( face );
if ( !exec )
return TT_Err_Could_Not_Find_Context;
Context_Load( exec, face, instance );
if ( instance )
{
if ( instance->GS.instruct_control & 2 )
exec->GS = Default_GraphicsState;
else
exec->GS = instance->GS;
/* load default graphics state */
glyph->outline.high_precision = ( instance->metrics.y_ppem < 24 );
}
/* save its critical pointers, as they'll be modified during load */
base_pts = exec->pts;
/* init variables */
left_points = face->maxPoints;
left_contours = face->maxContours;
num_points = 0;
num_contours = 0;
load_top = 0;
subglyph = exec->loadStack;
Init_Glyph_Component( subglyph, NULL, exec );
subglyph->index = glyph_index;
subglyph->is_hinted = load_flags & TTLOAD_HINT_GLYPH;
/* when the cvt program has disabled hinting, the argument */
/* is ignored. */
if ( instance && instance->GS.instruct_control & 1 )
subglyph->is_hinted = FALSE;
/* now access stream */
if ( USE_Stream( face->stream, stream ) )
goto Fin;
/* Main loading loop */
phase = Load_Glyph;
index = 0;
while ( phase != Load_Exit )
{
subglyph = exec->loadStack + load_top;
switch ( phase )
{
/************************************************************/
/* */
/* Load_Glyph state */
/* */
/* reading a glyph's generic header to determine */
/* whether it's simple or composite */
/* */
/* exit states: Load_Header and Load_End */
case Load_Glyph:
/* check glyph index and table */
index = subglyph->index;
if ( index < 0 || index >= face->numGlyphs )
{
error = TT_Err_Invalid_Glyph_Index;
goto Fail;
}
/* get horizontal metrics */
{
Short left_bearing;
UShort advance_width;
Get_HMetrics( face, (UShort)index,
!(load_flags & TTLOAD_IGNORE_GLOBAL_ADVANCE_WIDTH),
&left_bearing,
&advance_width );
subglyph->metrics.horiBearingX = left_bearing;
subglyph->metrics.horiAdvance = advance_width;
}
phase = Load_Header;
/* The cache callback isn't part of the FreeType release yet */
/* It is discarded for the moment.. */
/* */
#if 0
if ( instance )
{
/* is the glyph in an outline cache ? */
cacheCb = instance->owner->engine->glCallback;
if ( cacheCb && 0 ) /* disabled */
{
/* we have a callback */
error = cacheCb( instance->generic,
index, &cached_outline, &x, &y );
if ( !error )
{
/* no error, then append the outline to the current subglyph */
/* error = Append_Outline( subglyph,
&left_points,
&left_contours,
&cached_outline ); */
phase = Load_End;
}
}
}
#endif
break;
/************************************************************/
/* */
/* Load_Header state */
/* */
/* reading a glyph's generic header to determine */
/* wether it's simple or composite */
/* */
/* exit states: Load_Simple and Load_Composite */
/* */
case Load_Header: /* load glyph */
if ( (TT_UInt)( index + 1 ) < (TT_UInt)face->numLocations &&
face->glyphLocations[index] == face->glyphLocations[index + 1] )
{
/* as described by Frederic Loyer, these are spaces, and */
/* not the unknown glyph. */
num_contours = 0;
num_points = 0;
subglyph->metrics.bbox.xMin = 0;
subglyph->metrics.bbox.xMax = 0;
subglyph->metrics.bbox.yMin = 0;
subglyph->metrics.bbox.yMax = 0;
subglyph->pp1.x = 0;
subglyph->pp2.x = subglyph->metrics.horiAdvance;
if (load_flags & TTLOAD_SCALE_GLYPH)
subglyph->pp2.x = Scale_X( &exec->metrics, subglyph->pp2.x );
exec->glyphSize = 0;
phase = Load_End;
break;
}
offset = glyph_offset + face->glyphLocations[index];
/* read first glyph header */
if ( FILE_Seek( offset ) ||
ACCESS_Frame( 10L ) )
goto Fail_File;
num_contours = GET_Short();
subglyph->metrics.bbox.xMin = GET_Short();
subglyph->metrics.bbox.yMin = GET_Short();
subglyph->metrics.bbox.xMax = GET_Short();
subglyph->metrics.bbox.yMax = GET_Short();
FORGET_Frame();
PTRACE6(( "Glyph %ld:\n", index ));
PTRACE6(( " # of contours: %d\n", num_contours ));
PTRACE6(( " xMin: %4d xMax: %4d\n",
subglyph->metrics.bbox.xMin,
subglyph->metrics.bbox.xMax ));
PTRACE6(( " yMin: %4d yMax: %4d\n",
subglyph->metrics.bbox.yMin,
subglyph->metrics.bbox.yMax ));
if ( num_contours > left_contours )
{
PTRACE0(( "ERROR: Too many contours for glyph %ld\n", index ));
error = TT_Err_Too_Many_Contours;
goto Fail;
}
subglyph->pp1.x = subglyph->metrics.bbox.xMin -
subglyph->metrics.horiBearingX;
subglyph->pp1.y = 0;
subglyph->pp2.x = subglyph->pp1.x + subglyph->metrics.horiAdvance;
if (load_flags & TTLOAD_SCALE_GLYPH)
{
subglyph->pp1.x = Scale_X( &exec->metrics, subglyph->pp1.x );
subglyph->pp2.x = Scale_X( &exec->metrics, subglyph->pp2.x );
}
/* is it a simple glyph ? */
if ( num_contours > 0 )
phase = Load_Simple;
else
phase = Load_Composite;
break;
/************************************************************/
/* */
/* Load_Simple state */
/* */
/* reading a simple glyph (num_contours must be set to */
/* the glyph's number of contours.) */
/* */
/* exit states : Load_End */
/* */
case Load_Simple:
new_flags = load_flags;
/* disable hinting when scaling */
if ( !subglyph->is_hinted )
new_flags &= ~TTLOAD_HINT_GLYPH;
error = Load_Simple_Glyph( exec,
stream,
num_contours,
left_contours,
left_points,
new_flags,
subglyph );
if ( error )
goto Fail;
/* Note: We could have put the simple loader source there */
/* but the code is fat enough already :-) */
num_points = exec->pts.n_points - 2;
phase = Load_End;
break;
/************************************************************/
/* */
/* Load_Composite state */
/* */
/* reading a composite glyph header a pushing a new */
/* load element on the stack. */
/* */
/* exit states: Load_Glyph */
/* */
case Load_Composite:
/* create a new element on the stack */
load_top++;
if ( load_top > face->maxComponents )
{
error = TT_Err_Invalid_Composite;
goto Fail;
}
subglyph2 = exec->loadStack + load_top;
Init_Glyph_Component( subglyph2, subglyph, NULL );
subglyph2->is_hinted = subglyph->is_hinted;
/* now read composite header */
if ( ACCESS_Frame( 4L ) )
goto Fail_File;
subglyph->element_flag = new_flags = GET_UShort();
subglyph2->index = GET_UShort();
FORGET_Frame();
k = 1 + 1;
if ( new_flags & ARGS_ARE_WORDS )
k *= 2;
if ( new_flags & WE_HAVE_A_SCALE )
k += 2;
else if ( new_flags & WE_HAVE_AN_XY_SCALE )
k += 4;
else if ( new_flags & WE_HAVE_A_2X2 )
k += 8;
if ( ACCESS_Frame( k ) )
goto Fail_File;
if ( new_flags & ARGS_ARE_WORDS )
{
k = GET_Short();
l = GET_Short();
}
else
{
k = GET_Char();
l = GET_Char();
}
subglyph->arg1 = k;
subglyph->arg2 = l;
if ( new_flags & ARGS_ARE_XY_VALUES )
{
subglyph->transform.ox = k;
subglyph->transform.oy = l;
}
xx = 1L << 16;
xy = 0;
yx = 0;
yy = 1L << 16;
if ( new_flags & WE_HAVE_A_SCALE )
{
xx = (Fixed)GET_Short() << 2;
yy = xx;
subglyph2->is_scaled = TRUE;
}
else if ( new_flags & WE_HAVE_AN_XY_SCALE )
{
xx = (Fixed)GET_Short() << 2;
yy = (Fixed)GET_Short() << 2;
subglyph2->is_scaled = TRUE;
}
else if ( new_flags & WE_HAVE_A_2X2 )
{
xx = (Fixed)GET_Short() << 2;
xy = (Fixed)GET_Short() << 2;
yx = (Fixed)GET_Short() << 2;
yy = (Fixed)GET_Short() << 2;
subglyph2->is_scaled = TRUE;
}
FORGET_Frame();
subglyph->transform.xx = xx;
subglyph->transform.xy = xy;
subglyph->transform.yx = yx;
subglyph->transform.yy = yy;
k = TT_MulFix( xx, yy ) - TT_MulFix( xy, yx );
/* disable hinting in case of scaling/slanting */
if ( ABS( k ) != (1L << 16) )
subglyph2->is_hinted = FALSE;
subglyph->file_offset = FILE_Pos();
phase = Load_Glyph;
break;
/************************************************************/
/* */
/* Load_End state */
/* */
/* after loading a glyph, apply transformation and offset */
/* where necessary, pops element and continue or */
/* stop process. */
/* */
/* exit states : Load_Composite and Load_Exit */
/* */
case Load_End:
if ( load_top > 0 )
{
subglyph2 = subglyph;
load_top--;
subglyph = exec->loadStack + load_top;
/* check advance width and left side bearing */
if ( !subglyph->preserve_pps &&
subglyph->element_flag & USE_MY_METRICS )
{
subglyph->metrics.horiBearingX = subglyph2->metrics.horiBearingX;
subglyph->metrics.horiAdvance = subglyph2->metrics.horiAdvance;
subglyph->pp1 = subglyph2->pp1;
subglyph->pp2 = subglyph2->pp2;
subglyph->preserve_pps = TRUE;
}
/* apply scale */
if ( subglyph2->is_scaled )
{
TT_Vector* cur = subglyph2->zone.cur;
TT_Vector* org = subglyph2->zone.org;
for ( u = 0; u < num_points; u++ )
{
nx = TT_MulFix( cur->x, subglyph->transform.xx ) +
TT_MulFix( cur->y, subglyph->transform.yx );
ny = TT_MulFix( cur->x, subglyph->transform.xy ) +
TT_MulFix( cur->y, subglyph->transform.yy );
cur->x = nx;
cur->y = ny;
nx = TT_MulFix( org->x, subglyph->transform.xx ) +
TT_MulFix( org->y, subglyph->transform.yx );
ny = TT_MulFix( org->x, subglyph->transform.xy ) +
TT_MulFix( org->y, subglyph->transform.yy );
org->x = nx;
org->y = ny;
cur++;
org++;
}
}
/* adjust counts */
num_elem_points = subglyph->zone.n_points;
for ( k = 0; k < num_contours; k++ )
subglyph2->zone.contours[k] += num_elem_points;
subglyph->zone.n_points += num_points;
subglyph->zone.n_contours += num_contours;
left_points -= num_points;
left_contours -= num_contours;
if ( !(subglyph->element_flag & ARGS_ARE_XY_VALUES) )
{
/* move second glyph according to control points */
/* the attach points are relative to the specific component */
u = (UShort)subglyph->arg1;
v = (UShort)subglyph->arg2;
if ( u >= num_elem_points ||
v >= num_points )
{
error = TT_Err_Invalid_Composite;
goto Fail;
}
/* adjust count */
v += num_elem_points;
x = subglyph->zone.cur[u].x - subglyph->zone.cur[v].x;
y = subglyph->zone.cur[u].y - subglyph->zone.cur[v].y;
}
else
{
/* apply offset */
x = subglyph->transform.ox;
y = subglyph->transform.oy;
if ( load_flags & TTLOAD_SCALE_GLYPH )
{
x = Scale_X( &exec->metrics, x );
y = Scale_Y( &exec->metrics, y );
if ( subglyph->element_flag & ROUND_XY_TO_GRID )
{
x = (x+32) & -64;
y = (y+32) & -64;
}
}
}
translate_array( num_points, subglyph2->zone.cur, x, y );
cur_to_org( num_points, &subglyph2->zone );
num_points = subglyph->zone.n_points;
num_contours = subglyph->zone.n_contours;
/* check for last component */
if ( FILE_Seek( subglyph->file_offset ) )
goto Fail_File;
if ( subglyph->element_flag & MORE_COMPONENTS )
phase = Load_Composite;
else
{
error = Load_Composite_End( num_points,
num_contours,
exec,
subglyph,
load_flags,
stream );
if ( error )
goto Fail;
phase = Load_End;
}
}
else
phase = Load_Exit;
break;
case Load_Exit:
break;
}
}
/* finally, copy the points arrays to the glyph object */
exec->pts = base_pts;
for ( u = 0; u < num_points + 2; u++ )
{
glyph->outline.points[u] = exec->pts.cur[u];
glyph->outline.flags [u] = exec->pts.touch[u];
}
for ( k = 0; k < num_contours; k++ )
glyph->outline.contours[k] = exec->pts.contours[k];
glyph->outline.n_points = num_points;
glyph->outline.n_contours = num_contours;
glyph->outline.second_pass = TRUE;
/* translate array so that (0,0) is the glyph's origin */
translate_array( num_points + 2,
glyph->outline.points,
-subglyph->pp1.x,
0 );
TT_Get_Outline_BBox( &glyph->outline, &glyph->metrics.bbox );
if ( subglyph->is_hinted )
{
/* grid-fit the bounding box */
glyph->metrics.bbox.xMin &= -64;
glyph->metrics.bbox.yMin &= -64;
glyph->metrics.bbox.xMax = (glyph->metrics.bbox.xMax+63) & -64;
glyph->metrics.bbox.yMax = (glyph->metrics.bbox.yMax+63) & -64;
}
/* get the device-independent scaled horizontal metrics */
/* take care of fixed-pitch fonts... */
{
TT_Pos left_bearing;
TT_Pos advance;
left_bearing = subglyph->metrics.horiBearingX;
advance = subglyph->metrics.horiAdvance;
if ( face->postscript.isFixedPitch )
advance = face->horizontalHeader.advance_Width_Max;
if ( load_flags & TTLOAD_SCALE_GLYPH )
{
left_bearing = Scale_X( &exec->metrics, left_bearing );
advance = Scale_X( &exec->metrics, advance );
}
glyph->metrics.linearHoriBearingX = left_bearing;
glyph->metrics.linearHoriAdvance = advance;
}
glyph->metrics.horiBearingX = glyph->metrics.bbox.xMin;
glyph->metrics.horiBearingY = glyph->metrics.bbox.yMax;
glyph->metrics.horiAdvance = subglyph->pp2.x - subglyph->pp1.x;
/* Now take care of vertical metrics. In the case where there is */
/* no vertical information within the font (relatively common), make */
/* up some metrics `by hand' ... */
{
Short top_bearing; /* vertical top side bearing (EM units) */
UShort advance_height; /* vertical advance height (EM units) */
TT_Pos left; /* scaled vertical left side bearing */
TT_Pos orig_top; /* scaled original vertical top side bearing */
TT_Pos top; /* scaled vertical top side bearing */
TT_Pos advance; /* scaled vertical advance height */
/* Get the unscaled `tsb' and `ah' values */
if ( face->verticalInfo &&
face->verticalHeader.number_Of_VMetrics > 0 )
{
/* Don't assume that both the vertical header and vertical */
/* metrics are present in the same font :-) */
TT_Get_Metrics( (TT_Horizontal_Header*)&face->verticalHeader,
glyph_index,
&top_bearing,
&advance_height );
}
else
{
/* Make up the distances from the horizontal header.. */
/* NOTE: The OS/2 values are the only `portable' ones, */
/* which is why we use them... */
/* */
/* NOTE2: The sTypoDescender is negative, which is why */
/* we compute the baseline-to-baseline distance */
/* here with : */
/* ascender - descender + linegap */
/* */
/* XXX What happens here with these Apple fonts without OS/2 table ? */
top_bearing = (Short) (face->os2.sTypoLineGap / 2);
advance_height = (UShort)(face->os2.sTypoAscender -
face->os2.sTypoDescender +
face->os2.sTypoLineGap);
}
/* We must adjust the top_bearing value from the bounding box */
/* given in the glyph header to te bounding box calculated with */
/* TT_Get_Outline_BBox() */
/* scale the metrics */
if ( load_flags & TTLOAD_SCALE_GLYPH )
{
orig_top = Scale_Y( &exec->metrics, top_bearing );
top = Scale_Y( &exec->metrics,
top_bearing + subglyph->metrics.bbox.yMax ) -
glyph->metrics.bbox.yMax;
advance = Scale_Y( &exec->metrics, advance_height );
}
else
{
orig_top = top_bearing;
top = top_bearing + subglyph->metrics.bbox.yMax -
glyph->metrics.bbox.yMax;
advance = advance_height;
}
glyph->metrics.linearVertBearingY = orig_top;
glyph->metrics.linearVertAdvance = advance;
/* XXX : for now, we have no better algo for the lsb, but it should */
/* work ok.. */
/* */
left = ( glyph->metrics.bbox.xMin - glyph->metrics.bbox.xMax ) / 2;
/* grid-fit them if necessary */
if ( subglyph->is_hinted )
{
left &= -64;
top = (top + 63) & -64;
advance = (advance + 32) & -64;
}
glyph->metrics.vertBearingX = left;
glyph->metrics.vertBearingY = top;
glyph->metrics.vertAdvance = advance;
}
/* Adjust advance width to the value contained in the hdmx table. */
if ( !exec->face->postscript.isFixedPitch && instance &&
subglyph->is_hinted )
{
widths = Get_Advance_Widths( exec->face,
exec->instance->metrics.x_ppem );
if ( widths )
glyph->metrics.horiAdvance = widths[glyph_index] << 6;
}
glyph->outline.dropout_mode = (Char)exec->GS.scan_type;
error = TT_Err_Ok;
Fail_File:
Fail:
DONE_Stream( stream );
Fin:
/* reset the execution context */
exec->pts = base_pts;
if ( !instance || !instance->debug )
Done_Context( exec );
return error;
}
