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-rw-r--r--unicode/src/base/UFont.pas179
1 files changed, 108 insertions, 71 deletions
diff --git a/unicode/src/base/UFont.pas b/unicode/src/base/UFont.pas
index 346f4a07..ce52ed96 100644
--- a/unicode/src/base/UFont.pas
+++ b/unicode/src/base/UFont.pas
@@ -464,7 +464,7 @@ type
* The bitmap must be 2* pixels wider and higher than the
* original glyph's bitmap with the latter centered in it.
*}
- procedure Extrude(var TexBuffer: TGLubyteDynArray; Outset: single);
+ procedure StrokeBorder(var Glyph: FT_Glyph);
{**
* Creates an OpenGL texture (and display list) for the glyph.
@@ -496,6 +496,8 @@ type
property CharIndex: FT_UInt read fCharIndex;
end;
+ TFontPart = ( fpNone, fpInner, fpOutline );
+
{**
* Freetype font class.
*}
@@ -511,6 +513,7 @@ type
fLoadFlags: FT_Int32; //**< FT glpyh load-flags
fFontUnitScale: TPositionDbl; //**< FT font-units to pixel ratio
fUseDisplayLists: boolean; //**< true: use display-lists, false: direct drawing
+ fPart: TFontPart; //**< indicates the part of an outline font
{** @seealso TCachedFont.LoadGlyph }
function LoadGlyph(ch: UCS4Char): TGlyph; override;
@@ -1416,6 +1419,7 @@ begin
fOutset := Outset;
fLoadFlags := LoadFlags;
fUseDisplayLists := true;
+ fPart := fpNone;
// load font information
if (FT_New_Face(TFreeType.GetLibrary(), PChar(Filename), 0, fFace) <> 0) then
@@ -1708,7 +1712,9 @@ begin
fOutset := Outset;
fInnerFont := TFTFont.Create(Filename, Size, 0.0, LoadFlags);
+ fInnerFont.fPart := fpInner;
fOutlineFont := TFTFont.Create(Filename, Size, Outset, LoadFlags);
+ fOutlineFont.fPart := fpOutline;
ResetIntern();
end;
@@ -1970,82 +1976,113 @@ const
*}
cTexSmoothBorder = 1;
-procedure TFTGlyph.Extrude(var TexBuffer: TGLubyteDynArray; Outset: single);
+procedure TFTGlyph.StrokeBorder(var Glyph: FT_Glyph);
+var
+ Outline: PFT_Outline;
+ OuterStroker, InnerStroker: FT_Stroker;
+ OuterNumPoints, InnerNumPoints, GlyphNumPoints: FT_UInt;
+ OuterNumContours, InnerNumContours, GlyphNumContours: FT_UInt;
+ OuterBorder, InnerBorder: FT_StrokerBorder;
+ OutlineFlags: FT_Int;
+ UseStencil: boolean;
+begin
+ // It is possible to extrude the borders of a glyph with FT_Glyph_Stroke
+ // but it will extrude the border to the outside and the inside of a glyph
+ // although we just want to extrude to the outside.
+ // FT_Glyph_StrokeBorder extrudes to the outside but also fills the interior
+ // (this is what we need for bold fonts).
+ // In both cases the inner font and outline font (border) will overlap.
+ // Normally this does not matter but it does if alpha blending is active.
+ // In this case if e.g. the inner color is set to white, the outline to red
+ // and alpha to 0.5 the inner part will not be white it will be pink.
+
+ InnerStroker := nil;
+ OuterStroker := nil;
+
+ // If we are to create the interior of an outlined font (fInner = true)
+ // we have to create two borders:
+ // - one extruded to the outside by fOutset pixels and
+ // - one extruded to the inside by almost 0 zero pixels.
+ // The second one is used as a stencil for the first one, clearing the
+ // interiour of the glyph.
+ // The stencil is not needed to create bold fonts.
+ UseStencil := (fFont.fPart = fpInner);
+
+ Outline := @FT_OutlineGlyph(Glyph).outline;
+
+ OuterBorder := FT_Outline_GetOutsideBorder(Outline);
+ if (OuterBorder = FT_STROKER_BORDER_LEFT) then
+ InnerBorder := FT_STROKER_BORDER_RIGHT
+ else
+ InnerBorder := FT_STROKER_BORDER_LEFT;
+
+ { extrude outer border }
+
+ if (FT_Stroker_New(Glyph.library_, OuterStroker) <> 0) then
+ raise Exception.Create('FT_Stroker_New failed!');
+ FT_Stroker_Set(
+ OuterStroker,
+ Round(fOutset * 64),
+ FT_STROKER_LINECAP_ROUND,
+ FT_STROKER_LINEJOIN_BEVEL,
+ 0);
+
+ // similar to FT_Glyph_StrokeBorder(inner = FT_FALSE) but it is possible to
+ // use FT_Stroker_ExportBorder() afterwards to combine inner and outer borders
+ if (FT_Stroker_ParseOutline(OuterStroker, Outline, FT_FALSE) <> 0) then
+ raise Exception.Create('FT_Stroker_ParseOutline failed!');
- procedure SetToMax(var Val1: GLubyte; Val2: GLubyte); {$IFDEF HasInline}inline;{$ENDIF}
+ FT_Stroker_GetBorderCounts(OuterStroker, OuterBorder, OuterNumPoints, OuterNumContours);
+
+ { extrude inner border (= stencil) }
+
+ if (UseStencil) then
begin
- if (Val1 < Val2) then
- Val1 := Val2;
+ if (FT_Stroker_New(Glyph.library_, InnerStroker) <> 0) then
+ raise Exception.Create('FT_Stroker_New failed!');
+ FT_Stroker_Set(
+ InnerStroker,
+ 63, // extrude at most one pixel to avoid a black border
+ FT_STROKER_LINECAP_ROUND,
+ FT_STROKER_LINEJOIN_BEVEL,
+ 0);
+
+ if (FT_Stroker_ParseOutline(InnerStroker, Outline, FT_FALSE) <> 0) then
+ raise Exception.Create('FT_Stroker_ParseOutline failed!');
+
+ FT_Stroker_GetBorderCounts(InnerStroker, InnerBorder, InnerNumPoints, InnerNumContours);
+ end else begin
+ InnerNumPoints := 0;
+ InnerNumContours := 0;
end;
-var
- I, X, Y: integer;
- SrcBuffer,TmpBuffer: TGLubyteDynArray;
- TexLine, TexLinePrev, TexLineNext: PGLubyteArray;
- SrcLine: PGLubyteArray;
- AlphaScale: single;
- Value, ValueNeigh, ValueDiag: GLubyte;
-const
- // square-root of 2 used for diagonal neighbor pixels
- cSqrt2 = 1.4142;
- // number of ignored pixels on each edge of the bitmap. Consists of:
- // - border used for font smoothing and
- // - outer (extruded) bitmap pixel (because it is just written but never read)
- cBorder = cTexSmoothBorder + 1;
-begin
- // allocate memory for temporary buffer
- SetLength(SrcBuffer, Length(TexBuffer));
- FillChar(SrcBuffer[0], Length(TexBuffer), 0);
-
- // extrude pixel by pixel
- for I := 1 to Ceil(Outset) do
- begin
- // swap arrays
- TmpBuffer := TexBuffer;
- TexBuffer := SrcBuffer;
- SrcBuffer := TmpBuffer;
-
- // as long as we add an entire pixel of outset, use a solid color.
- // If the fractional part is reached blend, e.g. outline=3.2 -> 3 solid
- // pixels and one blended with alpha=0.2.
- // For the fractional part I = Ceil(Outset) is always true.
- if (I <= Outset) then
- AlphaScale := 1
- else
- AlphaScale := Outset - Trunc(Outset);
-
- // copy data to the expanded bitmap.
- for Y := cBorder to fTexSize.Height - 2*cBorder do
- begin
- TexLine := @TexBuffer[Y*fTexSize.Width];
- TexLinePrev := @TexBuffer[(Y-1)*fTexSize.Width];
- TexLineNext := @TexBuffer[(Y+1)*fTexSize.Width];
- SrcLine := @SrcBuffer[Y*fTexSize.Width];
+ { combine borders (subtract: OuterBorder - InnerBorder) }
- // expand current line's pixels
- for X := cBorder to fTexSize.Width - 2*cBorder do
- begin
- Value := SrcLine[X];
- ValueNeigh := Round(Value * AlphaScale);
- ValueDiag := Round(ValueNeigh / cSqrt2);
+ GlyphNumPoints := InnerNumPoints + OuterNumPoints;
+ GlyphNumContours := InnerNumContours + OuterNumContours;
- SetToMax(TexLine[X], Value);
- SetToMax(TexLine[X-1], ValueNeigh);
- SetToMax(TexLine[X+1], ValueNeigh);
+ // save flags before deletion (TODO: set them on the resulting outline)
+ OutlineFlags := Outline.flags;
- SetToMax(TexLinePrev[X], ValueNeigh);
- SetToMax(TexLinePrev[X-1], ValueDiag);
- SetToMax(TexLinePrev[X+1], ValueDiag);
+ // resize glyph outline to hold inner and outer border
+ FT_Outline_Done(Glyph.Library_, Outline);
+ if (FT_Outline_New(Glyph.Library_, GlyphNumPoints, GlyphNumContours, Outline) <> 0) then
+ raise Exception.Create('FT_Outline_New failed!');
- SetToMax(TexLineNext[X], ValueNeigh);
- SetToMax(TexLineNext[X-1], ValueDiag);
- SetToMax(TexLineNext[X+1], ValueDiag);
- end;
- end;
- end;
+ Outline.n_points := 0;
+ Outline.n_contours := 0;
- TmpBuffer := nil;
- SetLength(SrcBuffer, 0);
+ // add points to outline. The inner-border is used as a stencil.
+ FT_Stroker_ExportBorder(OuterStroker, OuterBorder, Outline);
+ if (UseStencil) then
+ FT_Stroker_ExportBorder(InnerStroker, InnerBorder, Outline);
+ if (FT_Outline_Check(outline) <> 0) then
+ raise Exception.Create('FT_Stroker_ExportBorder failed!');
+
+ if (InnerStroker <> nil) then
+ FT_Stroker_Done(InnerStroker);
+ if (OuterStroker <> nil) then
+ FT_Stroker_Done(OuterStroker);
end;
procedure TFTGlyph.CreateTexture(LoadFlags: FT_Int32);
@@ -2068,6 +2105,9 @@ begin
if (FT_Get_Glyph(fFont.Face^.glyph, Glyph) <> 0) then
raise Exception.Create('FT_Get_Glyph failed');
+ if (fOutset > 0) then
+ StrokeBorder(Glyph);
+
// store scaled advance width/height in glyph-object
fAdvance.X := fFont.Face^.glyph^.advance.x / 64 + fOutset*2;
fAdvance.Y := fFont.Face^.glyph^.advance.y / 64 + fOutset*2;
@@ -2149,9 +2189,6 @@ begin
end;
end;
- if (fOutset > 0) then
- Extrude(TexBuffer, fOutset);
-
// allocate resources for textures and display lists
glGenTextures(1, @fTexture);
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-01 12:14:10 +0000