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create/src/Mod/Part/App/FT2FC.cpp

348 lines
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/***************************************************************************
* Copyright (c) wandererfan <wandererfan (at) gmail.com> 2013 *
* *
* This file is part of the FreeCAD CAx development system. *
* *
* This library is free software; you can redistribute it and/or *
* modify it under the terms of the GNU Library General Public *
* License as published by the Free Software Foundation; either *
* version 2 of the License, or (at your option) any later version. *
* *
* This library is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
* GNU Library General Public License for more details. *
* *
* You should have received a copy of the GNU Library General Public *
* License along with this library; see the file COPYING.LIB. If not, *
* write to the Free Software Foundation, Inc., 59 Temple Place, *
* Suite 330, Boston, MA 02111-1307, USA *
* *
***************************************************************************/
/***************************************************************************
* FreeType License (FTL) credit: *
* Portions of this software are copyright (c) <1996-2011> The FreeType *
* Project (www.freetype.org). All rights reserved. *
***************************************************************************/
#ifdef FCUseFreeType
#include "PreCompiled.h"
#include <iostream>
#include <fstream>
#include <string>
#include <sstream>
#include <cstdio>
#include <cstdlib>
#include <stdexcept>
#include <vector>
#include <BRepLib.hxx>
#include <BRepBuilderAPI_MakeEdge.hxx>
#include <BRepBuilderAPI_MakeWire.hxx>
#include <BRepBuilderAPI_Transform.hxx>
#include <gp_Pnt.hxx>
#include <gp_Vec.hxx>
#include <TopoDS.hxx>
#include <TopoDS_Edge.hxx>
#include <TopoDS_Wire.hxx>
#include <TColgp_Array1OfPnt2d.hxx>
#include <GCE2d_MakeSegment.hxx>
#include <Geom2d_TrimmedCurve.hxx>
#include <Geom_Plane.hxx>
#include <Geom2d_BezierCurve.hxx>
#include <gp_Trsf.hxx>
#include <Precision.hxx>
#include <Base/Console.h>
#include "TopoShape.h"
#include "TopoShapePy.h"
#include "TopoShapeEdgePy.h"
#include "TopoShapeWirePy.h"
#include <ft2build.h>
#include FT_FREETYPE_H
#include FT_OUTLINE_H
#include FT_GLYPH_H
#include FT_TYPES_H
#include "FT2FC.h"
using namespace Part;
typedef unsigned long UNICHAR; // ul is FT2's codepoint type <=> Py_UNICODE2/4
// Private function prototypes
PyObject* getGlyphContours(FT_Face FTFont, UNICHAR currchar, double PenPos, double Scale);
FT_Vector getKerning(FT_Face FTFont, UNICHAR lc, UNICHAR rc);
TopoDS_Wire edgesToWire(std::vector<TopoDS_Edge> Edges);
// for compatibility with old version - separate path & filename
PyObject* FT2FC(const Py_UNICODE *PyUString,
const size_t length,
const char *FontPath,
const char *FontName,
const double stringheight,
const double tracking) {
std::string FontSpec;
std::string tmpPath = FontPath; // can't concat const char*
std::string tmpName = FontName;
FontSpec = tmpPath + tmpName;
return (FT2FC(PyUString,length,FontSpec.c_str(),stringheight,tracking));
}
// get string's wires (contours) in FC/OCC coords
PyObject* FT2FC(const Py_UNICODE *PyUString,
const size_t length,
const char *FontSpec,
const double stringheight, // fc coords
const double tracking) { // fc coords
FT_Library FTLib;
FT_Face FTFont;
FT_Error error;
FT_Long FaceIndex = 0; // some fonts have multiple faces
FT_Vector kern;
FT_UInt FTLoadFlags = FT_LOAD_DEFAULT | FT_LOAD_NO_BITMAP;
std::stringstream ErrorMsg;
double PenPos = 0, scalefactor;
UNICHAR prevchar = 0, currchar = 0;
int cadv;
size_t i;
PyObject *WireList, *CharList;
error = FT_Init_FreeType(&FTLib);
if(error) {
ErrorMsg << "FT_Init_FreeType failed: " << error;
throw std::runtime_error(ErrorMsg.str());
}
// FT does not return an error if font file not found?
std::ifstream is;
is.open (FontSpec);
if (!is) {
ErrorMsg << "Font file not found: " << FontSpec;
throw std::runtime_error(ErrorMsg.str());
}
error = FT_New_Face(FTLib,FontSpec,FaceIndex, &FTFont);
if(error) {
ErrorMsg << "FT_New_Face failed: " << error;
throw std::runtime_error(ErrorMsg.str());
}
//TODO: check that FTFont is scalable? only relevant for hinting etc?
// FT2 blows up if char size is not set to some non-zero value.
// This sets size to 48 point. Magic.
error = FT_Set_Char_Size(FTFont,
0, /* char_width in 1/64th of points */
48*64, /* char_height in 1/64th of points */
0, /* horizontal device resolution */
0 ); /* vertical device resolution */
if(error) {
ErrorMsg << "FT_Set_Char_Size failed: " << error;
throw std::runtime_error(ErrorMsg.str());
}
CharList = PyList_New(0);
scalefactor = stringheight/float(FTFont->height);
for (i=0; i<length; i++) {
currchar = PyUString[i];
error = FT_Load_Char(FTFont,
currchar,
FTLoadFlags);
if(error) {
ErrorMsg << "FT_Load_Char failed: " << error;
throw std::runtime_error(ErrorMsg.str());
}
cadv = FTFont->glyph->advance.x;
kern = getKerning(FTFont,prevchar,currchar);
PenPos += kern.x;
WireList = getGlyphContours(FTFont,currchar,PenPos, scalefactor);
if (!PyList_Size(WireList)) // empty ==> whitespace
Base::Console().Log("FT2FC char '0x%04x'/'%d' has no Wires!\n", currchar, currchar);
else
PyList_Append(CharList, WireList);
PenPos += (cadv + tracking);
prevchar = currchar;
}
error = FT_Done_FreeType(FTLib);
if(error) {
ErrorMsg << "FT_Done_FreeType failed: " << error;
throw std::runtime_error(ErrorMsg.str());
}
return(CharList);
}
//********** FT Decompose callbacks and data defns
// FT Decomp Context for 1 char
struct FTDC_Ctx {
std::vector<TopoDS_Wire> Wires;
std::vector<TopoDS_Edge> Edges;
UNICHAR currchar;
FT_Vector LastVert;
Handle_Geom_Surface surf;
};
// move_cb called for start of new contour. pt is xy of contour start.
// p points to the context where we remember what happened previously (last point, etc)
static int move_cb(const FT_Vector* pt, void* p) {
FTDC_Ctx* dc = (FTDC_Ctx*) p;
if (!dc->Edges.empty()){
TopoDS_Wire newwire = edgesToWire(dc->Edges);
dc->Wires.push_back(newwire);
dc->Edges.clear();
}
dc->LastVert = *pt;
return 0;
}
// line_cb called for line segment in the current contour: line(LastVert -- pt)
static int line_cb(const FT_Vector* pt, void* p) {
FTDC_Ctx* dc = (FTDC_Ctx*) p;
gp_Pnt2d v1(dc->LastVert.x, dc->LastVert.y);
gp_Pnt2d v2(pt->x, pt->y);
if (!v1.IsEqual(v2, Precision::Confusion())) {
Handle(Geom2d_TrimmedCurve) lseg = GCE2d_MakeSegment(v1,v2);
TopoDS_Edge edge = BRepBuilderAPI_MakeEdge(lseg , dc->surf);
dc->Edges.push_back(edge);
dc->LastVert = *pt;
}
return 0;
}
// quad_cb called for quadratic (conic) BCurve segment in the current contour
// (ie V-C-V in TTF fonts). BCurve(LastVert -- pt0 -- pt1)
static int quad_cb(const FT_Vector* pt0, const FT_Vector* pt1, void* p) {
FTDC_Ctx* dc = (FTDC_Ctx*) p;
TColgp_Array1OfPnt2d Poles(1,3);
gp_Pnt2d v1(dc->LastVert.x, dc->LastVert.y);
gp_Pnt2d c1(pt0->x, pt0->y);
gp_Pnt2d v2(pt1->x, pt1->y);
Poles.SetValue(1, v1);
Poles.SetValue(2, c1);
Poles.SetValue(3, v2);
Handle(Geom2d_BezierCurve) bcseg = new Geom2d_BezierCurve(Poles);
TopoDS_Edge edge = BRepBuilderAPI_MakeEdge(bcseg , dc->surf);
dc->Edges.push_back(edge);
dc->LastVert = *pt1;
return 0;
}
// cubic_cb called for cubic BCurve segment in the current contour (ie V-C-C-V in
// Type 1 fonts). BCurve(LastVert -- pt0 -- pt1 -- pt2)
static int cubic_cb(const FT_Vector* pt0, const FT_Vector* pt1, const FT_Vector* pt2, void* p) {
FTDC_Ctx* dc = (FTDC_Ctx*) p;
TColgp_Array1OfPnt2d Poles(1,4);
gp_Pnt2d v1(dc->LastVert.x, dc->LastVert.y);
gp_Pnt2d c1(pt0->x, pt0->y);
gp_Pnt2d c2(pt1->x, pt1->y);
gp_Pnt2d v2(pt2->x, pt2->y);
Poles.SetValue(1, v1);
Poles.SetValue(2, c1);
Poles.SetValue(3, c2);
Poles.SetValue(4, v2);
Handle(Geom2d_BezierCurve) bcseg = new Geom2d_BezierCurve(Poles);
TopoDS_Edge edge = BRepBuilderAPI_MakeEdge(bcseg , dc->surf);
dc->Edges.push_back(edge);
dc->LastVert = *pt2;
return 0;
}
// FT Callbacks structure
static FT_Outline_Funcs FTcbFuncs = {
(FT_Outline_MoveToFunc)move_cb,
(FT_Outline_LineToFunc)line_cb,
(FT_Outline_ConicToFunc)quad_cb,
(FT_Outline_CubicToFunc)cubic_cb,
0, 0 // not needed for FC
};
//********** FT2FC Helpers
// get glyph outline in wires
PyObject* getGlyphContours(FT_Face FTFont, UNICHAR currchar, double PenPos, double Scale) {
FT_Error error = 0;
std::stringstream ErrorMsg;
gp_Pnt origin = gp_Pnt(0.0,0.0,0.0);
FTDC_Ctx ctx;
ctx.currchar = currchar;
ctx.surf = new Geom_Plane(origin,gp::DZ());
error = FT_Outline_Decompose(&FTFont->glyph->outline,
&FTcbFuncs,
&ctx);
if(error) {
ErrorMsg << "FT_Decompose failed: " << error;
throw std::runtime_error(ErrorMsg.str());
}
// make the last TopoDS_Wire
if (!ctx.Edges.empty()){
ctx.Wires.push_back(edgesToWire(ctx.Edges));
}
/*FT_Orientation fontClass =*/ FT_Outline_Get_Orientation(&FTFont->glyph->outline);
PyObject* ret = PyList_New(0);
gp_Vec pointer = gp_Vec(PenPos * Scale,0.0,0.0);
gp_Trsf xForm;
xForm.SetScale(origin,Scale);
xForm.SetTranslationPart(pointer);
BRepBuilderAPI_Transform BRepScale(xForm);
bool bCopy = true; // no effect?
for(std::vector<TopoDS_Wire>::iterator iWire=ctx.Wires.begin();iWire != ctx.Wires.end();++iWire) {
BRepScale.Perform(*iWire,bCopy);
if (!BRepScale.IsDone()) {
ErrorMsg << "FT2FC OCC BRepScale failed \n";
throw std::runtime_error(ErrorMsg.str());
}
PyList_Append(ret,new TopoShapeWirePy(new TopoShape(TopoDS::Wire(BRepScale.Shape()))));
}
return(ret);
}
// get kerning values for this char pair
//TODO: should check FT_HASKERNING flag? returns (0,0) if no kerning?
FT_Vector getKerning(FT_Face FTFont, UNICHAR lc, UNICHAR rc) {
FT_Vector retXY;
FT_Error error;
std::stringstream ErrorMsg;
FT_Vector ftKern;
FT_UInt lcx = FT_Get_Char_Index(FTFont, lc);
FT_UInt rcx = FT_Get_Char_Index(FTFont, rc);
error = FT_Get_Kerning(FTFont,lcx,rcx,FT_KERNING_DEFAULT,&ftKern);
if(error) {
ErrorMsg << "FT_Get_Kerning failed: " << error;
throw std::runtime_error(ErrorMsg.str());
}
retXY.x = ftKern.x;
retXY.y = ftKern.y;
return(retXY);
}
// Make a TopoDS_Wire from a list of TopoDS_Edges
TopoDS_Wire edgesToWire(std::vector<TopoDS_Edge> Edges) {
TopoDS_Wire occwire;
std::vector<TopoDS_Edge>::iterator iEdge;
BRepBuilderAPI_MakeWire mkWire;
for (iEdge = Edges.begin(); iEdge != Edges.end(); ++iEdge){
mkWire.Add(*iEdge);
if (!mkWire.IsDone()) {
Base::Console().Message("FT2FC Trace edgesToWire failed to add wire\n");
}
}
occwire = mkWire.Wire();
BRepLib::BuildCurves3d(occwire);
return(occwire);
}
#endif //#ifdef FCUseFreeType