Edit
kc3-lang/ftgl/src/FTVectoriser.cpp
Ben Boeckel
- src/FTVectoriser.cpp
-
/* * FTGL - OpenGL font library * * Copyright (c) 2001-2004 Henry Maddocks <ftgl@opengl.geek.nz> * Copyright (c) 2008 Éric Beets <ericbeets@free.fr> * Copyright (c) 2008 Sam Hocevar <sam@hocevar.net> * * Permission is hereby granted, free of charge, to any person obtaining * a copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ #include "config.h" #include "FTInternals.h" #include "FTVectoriser.h" #ifndef CALLBACK #define CALLBACK #endif #if defined __APPLE_CC__ && __APPLE_CC__ < 5465 typedef GLvoid (*GLUTesselatorFunction) (...); #elif defined _WIN32 && !defined __CYGWIN__ typedef GLvoid (CALLBACK *GLUTesselatorFunction) (); #else typedef GLvoid (*GLUTesselatorFunction) (); #endif void CALLBACK ftglError(GLenum errCode, FTMesh* mesh) { mesh->Error(errCode); } void CALLBACK ftglVertex(void* data, FTMesh* mesh) { FTGL_DOUBLE* vertex = static_cast<FTGL_DOUBLE*>(data); mesh->AddPoint(vertex[0], vertex[1], vertex[2]); } void CALLBACK ftglCombine(FTGL_DOUBLE coords[3], void* vertex_data[4], GLfloat weight[4], void** outData, FTMesh* mesh) { (void)vertex_data; (void)weight; const FTGL_DOUBLE* vertex = static_cast<const FTGL_DOUBLE*>(coords); *outData = const_cast<FTGL_DOUBLE*>(mesh->Combine(vertex[0], vertex[1], vertex[2])); } void CALLBACK ftglBegin(GLenum type, FTMesh* mesh) { mesh->Begin(type); } void CALLBACK ftglEnd(FTMesh* mesh) { mesh->End(); } FTMesh::FTMesh() : currentTesselation(0), err(0) { tesselationList.reserve(16); } FTMesh::~FTMesh() { for(size_t t = 0; t < tesselationList.size(); ++t) { delete tesselationList[t]; } tesselationList.clear(); } void FTMesh::AddPoint(const FTGL_DOUBLE x, const FTGL_DOUBLE y, const FTGL_DOUBLE z) { currentTesselation->AddPoint(x, y, z); } const FTGL_DOUBLE* FTMesh::Combine(const FTGL_DOUBLE x, const FTGL_DOUBLE y, const FTGL_DOUBLE z) { tempPointList.push_back(FTPoint(x, y,z)); return static_cast<const FTGL_DOUBLE*>(tempPointList.back()); } void FTMesh::Begin(GLenum meshType) { currentTesselation = new FTTesselation(meshType); } void FTMesh::End() { tesselationList.push_back(currentTesselation); } FTTesselation const * FTMesh::Tesselation(size_t index) const { return (index < tesselationList.size()) ? tesselationList[index] : NULL; } FTVectoriser::FTVectoriser(const FT_GlyphSlot glyph) : contourList(0), mesh(0), ftContourCount(0), contourFlag(0) { if(glyph) { outline = glyph->outline; ftContourCount = outline.n_contours; contourList = 0; contourFlag = outline.flags; ProcessContours(); } } FTVectoriser::~FTVectoriser() { for(size_t c = 0; c < ContourCount(); ++c) { delete contourList[c]; } delete [] contourList; delete mesh; } void FTVectoriser::ProcessContours() { short contourLength = 0; short startIndex = 0; short endIndex = 0; contourList = new FTContour*[ftContourCount]; for(int i = 0; i < ftContourCount; ++i) { FT_Vector* pointList = &outline.points[startIndex]; char* tagList = &outline.tags[startIndex]; endIndex = outline.contours[i]; contourLength = (endIndex - startIndex) + 1; FTContour* contour = new FTContour(pointList, tagList, contourLength); contourList[i] = contour; startIndex = endIndex + 1; } // Compute each contour's parity. FIXME: see if FT_Outline_Get_Orientation // can do it for us. for(int i = 0; i < ftContourCount; i++) { FTContour *c1 = contourList[i]; // 1. Find the leftmost point. FTPoint leftmost(65536.0, 0.0); for(size_t n = 0; n < c1->PointCount(); n++) { FTPoint p = c1->Point(n); if(p.X() < leftmost.X()) { leftmost = p; } } // 2. Count how many other contours we cross when going further to // the left. int parity = 0; for(int j = 0; j < ftContourCount; j++) { if(j == i) { continue; } FTContour *c2 = contourList[j]; for(size_t n = 0; n < c2->PointCount(); n++) { FTPoint p1 = c2->Point(n); FTPoint p2 = c2->Point((n + 1) % c2->PointCount()); /* FIXME: combinations of >= > <= and < do not seem stable */ if((p1.Y() < leftmost.Y() && p2.Y() < leftmost.Y()) || (p1.Y() >= leftmost.Y() && p2.Y() >= leftmost.Y()) || (p1.X() > leftmost.X() && p2.X() > leftmost.X())) { continue; } else if(p1.X() < leftmost.X() && p2.X() < leftmost.X()) { parity++; } else { FTPoint a = p1 - leftmost; FTPoint b = p2 - leftmost; if(b.X() * a.Y() > b.Y() * a.X()) { parity++; } } } } // 3. Make sure the glyph has the proper parity. c1->SetParity(parity); } } size_t FTVectoriser::PointCount() { size_t s = 0; for(size_t c = 0; c < ContourCount(); ++c) { s += contourList[c]->PointCount(); } return s; } FTContour const * FTVectoriser::Contour(size_t index) const { return (index < ContourCount()) ? contourList[index] : NULL; } void FTVectoriser::MakeMesh(FTGL_DOUBLE zNormal, int outsetType, float outsetSize) { if(mesh) { delete mesh; } mesh = new FTMesh; GLUtesselator* tobj = gluNewTess(); gluTessCallback(tobj, GLU_TESS_BEGIN_DATA, (GLUTesselatorFunction)ftglBegin); gluTessCallback(tobj, GLU_TESS_VERTEX_DATA, (GLUTesselatorFunction)ftglVertex); gluTessCallback(tobj, GLU_TESS_COMBINE_DATA, (GLUTesselatorFunction)ftglCombine); gluTessCallback(tobj, GLU_TESS_END_DATA, (GLUTesselatorFunction)ftglEnd); gluTessCallback(tobj, GLU_TESS_ERROR_DATA, (GLUTesselatorFunction)ftglError); if(contourFlag & ft_outline_even_odd_fill) // ft_outline_reverse_fill { gluTessProperty(tobj, GLU_TESS_WINDING_RULE, GLU_TESS_WINDING_ODD); } else { gluTessProperty(tobj, GLU_TESS_WINDING_RULE, GLU_TESS_WINDING_NONZERO); } gluTessProperty(tobj, GLU_TESS_TOLERANCE, 0); gluTessNormal(tobj, 0.0f, 0.0f, zNormal); gluTessBeginPolygon(tobj, mesh); for(size_t c = 0; c < ContourCount(); ++c) { /* Build the */ switch(outsetType) { case 1 : contourList[c]->buildFrontOutset(outsetSize); break; case 2 : contourList[c]->buildBackOutset(outsetSize); break; } const FTContour* contour = contourList[c]; gluTessBeginContour(tobj); for(size_t p = 0; p < contour->PointCount(); ++p) { const FTGL_DOUBLE* d; switch(outsetType) { case 1: d = contour->FrontPoint(p); break; case 2: d = contour->BackPoint(p); break; case 0: default: d = contour->Point(p); break; } // XXX: gluTessVertex doesn't modify the data but does not // specify "const" in its prototype, so we cannot cast to // a const type. gluTessVertex(tobj, const_cast<GLdouble*>(d), (GLvoid *)d); } gluTessEndContour(tobj); } gluTessEndPolygon(tobj); gluDeleteTess(tobj); }