603 lines
19 KiB
C++
603 lines
19 KiB
C++
/*
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* This program source code file is part of KICAD, a free EDA CAD application.
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*
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* Copyright (C) 1992-2019 jean-pierre.charras
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* Copyright (C) 1992-2021 KiCad Developers, see AUTHORS.txt for contributors.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, you may find one here:
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* http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
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* or you may search the http://www.gnu.org website for the version 2 license,
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* or you may write to the Free Software Foundation, Inc.,
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* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
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*/
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#include <algorithm> // std::max
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#include <cerrno>
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#include <cmath>
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#include <cstdio>
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#include <cstdlib>
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#include <cstring>
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#include <string>
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#include <vector>
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#include <kiid.h>
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#include <layer_ids.h>
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#include <locale_io.h>
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#include <potracelib.h>
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#include "bitmap2component.h"
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/* free a potrace bitmap */
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static void bm_free( potrace_bitmap_t* bm )
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{
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if( bm != nullptr )
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{
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free( bm->map );
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}
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free( bm );
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}
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static void BezierToPolyline( std::vector <potrace_dpoint_t>& aCornersBuffer,
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potrace_dpoint_t p1,
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potrace_dpoint_t p2,
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potrace_dpoint_t p3,
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potrace_dpoint_t p4 );
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BITMAPCONV_INFO::BITMAPCONV_INFO( std::string& aData ):
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m_Data( aData )
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{
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m_Format = POSTSCRIPT_FMT;
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m_PixmapWidth = 0;
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m_PixmapHeight = 0;
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m_ScaleX = 1.0;
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m_ScaleY = 1.0;
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m_Paths = nullptr;
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m_CmpName = "LOGO";
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}
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int BITMAPCONV_INFO::ConvertBitmap( potrace_bitmap_t* aPotrace_bitmap, OUTPUT_FMT_ID aFormat,
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int aDpi_X, int aDpi_Y, BMP2CMP_MOD_LAYER aModLayer )
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{
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potrace_param_t* param;
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potrace_state_t* st;
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// set tracing parameters, starting from defaults
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param = potrace_param_default();
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if( !param )
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{
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char msg[256];
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sprintf( msg, "Error allocating parameters: %s\n", strerror( errno ) );
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m_errors += msg;
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return 1;
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}
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// For parameters: see http://potrace.sourceforge.net/potracelib.pdf
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param->turdsize = 0; // area (in pixels) of largest path to be ignored.
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// Potrace default is 2
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param->opttolerance = 0.2; // curve optimization tolerance. Potrace default is 0.2
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/* convert the bitmap to curves */
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st = potrace_trace( param, aPotrace_bitmap );
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if( !st || st->status != POTRACE_STATUS_OK )
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{
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if( st )
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{
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potrace_state_free( st );
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}
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potrace_param_free( param );
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char msg[256];
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sprintf( msg, "Error tracing bitmap: %s\n", strerror( errno ) );
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m_errors += msg;
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return 1;
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}
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m_PixmapWidth = aPotrace_bitmap->w;
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m_PixmapHeight = aPotrace_bitmap->h; // the bitmap size in pixels
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m_Paths = st->plist;
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switch( aFormat )
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{
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case KICAD_WKS_LOGO:
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m_Format = KICAD_WKS_LOGO;
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m_ScaleX = PL_IU_PER_MM * 25.4 / aDpi_X; // the conversion scale from PPI to micron
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m_ScaleY = PL_IU_PER_MM * 25.4 / aDpi_Y; // Y axis is top to bottom
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createOutputData();
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break;
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case POSTSCRIPT_FMT:
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m_Format = POSTSCRIPT_FMT;
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m_ScaleX = 1.0; // the conversion scale
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m_ScaleY = m_ScaleX;
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// output vector data, e.g. as a rudimentary EPS file (mainly for tests)
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createOutputData();
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break;
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case EESCHEMA_FMT:
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m_Format = EESCHEMA_FMT;
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m_ScaleX = SCH_IU_PER_MM * 25.4 / aDpi_X; // the conversion scale from PPI to eeschema iu
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m_ScaleY = -SCH_IU_PER_MM * 25.4 / aDpi_Y; // Y axis is bottom to Top for components in libs
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createOutputData();
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break;
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case PCBNEW_KICAD_MOD:
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m_Format = PCBNEW_KICAD_MOD;
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m_ScaleX = PCB_IU_PER_MM * 25.4 / aDpi_X; // the conversion scale from PPI to IU
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m_ScaleY = PCB_IU_PER_MM * 25.4 / aDpi_Y; // Y axis is top to bottom in Footprint Editor
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createOutputData( aModLayer );
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break;
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default:
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break;
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}
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bm_free( aPotrace_bitmap );
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potrace_state_free( st );
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potrace_param_free( param );
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return 0;
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}
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const char* BITMAPCONV_INFO::getBoardLayerName( BMP2CMP_MOD_LAYER aChoice )
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{
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const char* layerName = "F.SilkS";
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switch( aChoice )
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{
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case MOD_LYR_FSOLDERMASK:
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layerName = "F.Mask";
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break;
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case MOD_LYR_ECO1:
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layerName = "Eco1.User";
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break;
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case MOD_LYR_ECO2:
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layerName = "Eco2.User";
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break;
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case MOD_LYR_FSILKS:
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default: // case MOD_LYR_FSILKS only unless there is a bug
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break;
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}
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return layerName;
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}
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void BITMAPCONV_INFO::outputDataHeader( const char * aBrdLayerName )
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{
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double Ypos = ( m_PixmapHeight / 2 * m_ScaleY ); // fields Y position in mm
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double fieldSize; // fields text size in mm
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char strbuf[1024];
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switch( m_Format )
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{
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case POSTSCRIPT_FMT:
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/* output vector data, e.g. as a rudimentary EPS file */
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m_Data += "%%!PS-Adobe-3.0 EPSF-3.0\n";
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sprintf( strbuf, "%%%%BoundingBox: 0 0 %d %d\n", m_PixmapWidth, m_PixmapHeight );
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m_Data += strbuf;
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m_Data += "gsave\n";
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break;
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case PCBNEW_KICAD_MOD:
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// fields text size = 1.5 mm
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// fields text thickness = 1.5 / 5 = 0.3mm
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sprintf( strbuf,
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"(footprint \"%s\" (version 20221018) (generator bitmap2component)\n"
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" (layer \"F.Cu\")\n",
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m_CmpName.c_str() );
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m_Data += strbuf;
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sprintf( strbuf, " (attr board_only exclude_from_pos_files exclude_from_bom)\n" );
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m_Data += strbuf;
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sprintf( strbuf,
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" (fp_text reference \"G***\" (at 0 0) (layer \"%s\")\n"
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" (effects (font (size 1.5 1.5) (thickness 0.3)))\n"
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" (tstamp %s)\n )\n",
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aBrdLayerName, KIID().AsString().ToStdString().c_str() );
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m_Data += strbuf;
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sprintf( strbuf,
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" (fp_text value \"%s\" (at 0.75 0) (layer \"%s\") hide\n"
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" (effects (font (size 1.5 1.5) (thickness 0.3)))\n"
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" (tstamp %s)\n )\n",
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m_CmpName.c_str(), aBrdLayerName, KIID().AsString().ToStdString().c_str() );
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m_Data += strbuf;
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break;
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case KICAD_WKS_LOGO:
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m_Data += "(kicad_wks (version 20220228) (generator bitmap2component)\n";
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m_Data += " (setup (textsize 1.5 1.5)(linewidth 0.15)(textlinewidth 0.15)\n";
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m_Data += " (left_margin 10)(right_margin 10)(top_margin 10)(bottom_margin 10))\n";
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m_Data += " (polygon (name \"\") (pos 0 0) (linewidth 0.01)\n";
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break;
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case EESCHEMA_FMT:
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fieldSize = 1.27; // fields text size in mm (= 50 mils)
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Ypos /= SCH_IU_PER_MM;
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Ypos += fieldSize / 2;
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// sprintf( strbuf, "# pixmap size w = %d, h = %d\n#\n", m_PixmapWidth, m_PixmapHeight );
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sprintf( strbuf,
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"(kicad_symbol_lib (version 20220914) (generator bitmap2component)\n"
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" (symbol \"%s\" (pin_names (offset 1.016)) (in_bom yes) (on_board yes)\n",
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m_CmpName.c_str() );
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m_Data += strbuf;
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sprintf( strbuf,
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" (property \"Reference\" \"#G\" (at 0 %g 0)\n"
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" (effects (font (size %g %g)) hide)\n )\n",
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-Ypos, fieldSize, fieldSize );
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m_Data += strbuf;
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sprintf( strbuf,
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" (property \"Value\" \"%s\" (at 0 %g 0)\n"
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" (effects (font (size %g %g)) hide)\n )\n",
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m_CmpName.c_str(), Ypos, fieldSize, fieldSize );
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m_Data += strbuf;
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sprintf( strbuf,
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" (property \"Footprint\" \"\" (at 0 0 0)\n"
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" (effects (font (size %g %g)) hide)\n )\n",
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fieldSize, fieldSize );
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m_Data += strbuf;
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sprintf( strbuf,
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" (property \"Datasheet\" \"\" (at 0 0 0)\n"
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" (effects (font (size %g %g)) hide)\n )\n",
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fieldSize, fieldSize );
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m_Data += strbuf;
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sprintf( strbuf, " (symbol \"%s_0_0\"\n", m_CmpName.c_str() );
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m_Data += strbuf;
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break;
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}
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}
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void BITMAPCONV_INFO::outputDataEnd()
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{
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switch( m_Format )
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{
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case POSTSCRIPT_FMT:
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m_Data += "grestore\n";
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m_Data += "%%EOF\n";
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break;
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case PCBNEW_KICAD_MOD:
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m_Data += ")\n";
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break;
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case KICAD_WKS_LOGO:
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m_Data += " )\n)\n";
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break;
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case EESCHEMA_FMT:
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m_Data += " )\n"; // end symbol_0_0
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m_Data += " )\n"; // end symbol
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m_Data += ")\n"; // end lib
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break;
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}
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}
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void BITMAPCONV_INFO::outputOnePolygon( SHAPE_LINE_CHAIN& aPolygon, const char* aBrdLayerName )
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{
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// write one polygon to output file.
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// coordinates are expected in target unit.
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int ii, jj;
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VECTOR2I currpoint;
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char strbuf[1024];
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int offsetX = (int)( m_PixmapWidth / 2 * m_ScaleX );
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int offsetY = (int)( m_PixmapHeight / 2 * m_ScaleY );
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const VECTOR2I startpoint = aPolygon.CPoint( 0 );
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switch( m_Format )
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{
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case POSTSCRIPT_FMT:
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offsetY = (int)( m_PixmapHeight * m_ScaleY );
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sprintf( strbuf, "newpath\n%d %d moveto\n", startpoint.x, offsetY - startpoint.y );
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m_Data += strbuf;
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jj = 0;
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for( ii = 1; ii < aPolygon.PointCount(); ii++ )
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{
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currpoint = aPolygon.CPoint( ii );
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sprintf( strbuf, " %d %d lineto", currpoint.x, offsetY - currpoint.y );
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m_Data += strbuf;
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if( jj++ > 6 )
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{
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jj = 0;
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m_Data += "\n";
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}
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}
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m_Data += "\nclosepath fill\n";
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break;
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case PCBNEW_KICAD_MOD:
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{
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double width = 0.0; // outline thickness in mm: no thickness
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m_Data += " (fp_poly\n (pts\n";
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jj = 0;
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for( ii = 0; ii < aPolygon.PointCount(); ii++ )
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{
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currpoint = aPolygon.CPoint( ii );
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sprintf( strbuf, " (xy %f %f)\n",
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( currpoint.x - offsetX ) / PCB_IU_PER_MM,
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( currpoint.y - offsetY ) / PCB_IU_PER_MM );
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m_Data += strbuf;
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}
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// No need to close polygon
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m_Data += " )\n\n";
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sprintf( strbuf,
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" (stroke (width %f) (type solid)) (fill solid) (layer \"%s\") (tstamp %s))\n",
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width, aBrdLayerName, KIID().AsString().ToStdString().c_str() );
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m_Data += strbuf;
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}
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break;
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case KICAD_WKS_LOGO:
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m_Data += " (pts";
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// Internal units = micron, file unit = mm
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jj = 1;
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for( ii = 0; ii < aPolygon.PointCount(); ii++ )
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{
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currpoint = aPolygon.CPoint( ii );
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sprintf( strbuf, " (xy %.3f %.3f)",
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( currpoint.x - offsetX ) / PL_IU_PER_MM,
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( currpoint.y - offsetY ) / PL_IU_PER_MM );
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m_Data += strbuf;
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if( jj++ > 4 )
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{
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jj = 0;
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m_Data += "\n ";
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}
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}
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// Close polygon
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sprintf( strbuf, " (xy %.3f %.3f) )\n",
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( startpoint.x - offsetX ) / PL_IU_PER_MM,
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( startpoint.y - offsetY ) / PL_IU_PER_MM );
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m_Data += strbuf;
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break;
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case EESCHEMA_FMT:
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// The polygon outline thickness is fixed here to 0.01 ( 0.0 is the default thickness)
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#define SCH_LINE_THICKNESS_MM 0.01
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//sprintf( strbuf, "P %d 0 0 %d", (int) aPolygon.PointCount() + 1, EE_LINE_THICKNESS );
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m_Data += " (polyline\n (pts\n";
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for( ii = 0; ii < aPolygon.PointCount(); ii++ )
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{
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currpoint = aPolygon.CPoint( ii );
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sprintf( strbuf, " (xy %f %f)\n",
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( currpoint.x - offsetX ) / SCH_IU_PER_MM,
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( currpoint.y - offsetY ) / SCH_IU_PER_MM );
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m_Data += strbuf;
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}
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// Close polygon
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sprintf( strbuf, " (xy %f %f)\n",
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( startpoint.x - offsetX ) / SCH_IU_PER_MM,
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( startpoint.y - offsetY ) / SCH_IU_PER_MM );
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m_Data += strbuf;
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m_Data += " )\n"; // end pts
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sprintf( strbuf,
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" (stroke (width %g) (type default))\n (fill (type outline))\n",
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SCH_LINE_THICKNESS_MM );
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m_Data += strbuf;
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m_Data += " )\n"; // end polyline
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break;
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}
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}
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void BITMAPCONV_INFO::createOutputData( BMP2CMP_MOD_LAYER aModLayer )
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{
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std::vector <potrace_dpoint_t> cornersBuffer;
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// polyset_areas is a set of polygon to draw
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SHAPE_POLY_SET polyset_areas;
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// polyset_holes is the set of holes inside polyset_areas outlines
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SHAPE_POLY_SET polyset_holes;
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potrace_dpoint_t( *c )[3];
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LOCALE_IO toggle; // Temporary switch the locale to standard C to r/w floats
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// The layer name has meaning only for .kicad_mod files.
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// For these files the header creates 2 invisible texts: value and ref
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// (needed but not useful) on silk screen layer
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outputDataHeader( getBoardLayerName( MOD_LYR_FSILKS ) );
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bool main_outline = true;
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/* draw each as a polygon with no hole.
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* Bezier curves are approximated by a polyline
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*/
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potrace_path_t* paths = m_Paths; // the list of paths
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if(!m_Paths)
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{
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m_errors += "No shape in black and white image to convert: no outline created\n";
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}
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while( paths != nullptr )
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{
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int cnt = paths->curve.n;
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int* tag = paths->curve.tag;
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c = paths->curve.c;
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potrace_dpoint_t startpoint = c[cnt - 1][2];
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for( int i = 0; i < cnt; i++ )
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{
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switch( tag[i] )
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{
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case POTRACE_CORNER:
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cornersBuffer.push_back( c[i][1] );
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cornersBuffer.push_back( c[i][2] );
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startpoint = c[i][2];
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break;
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case POTRACE_CURVETO:
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BezierToPolyline( cornersBuffer, startpoint, c[i][0], c[i][1], c[i][2] );
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startpoint = c[i][2];
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break;
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}
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}
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// Store current path
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if( main_outline )
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{
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main_outline = false;
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// build the current main polygon
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polyset_areas.NewOutline();
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for( unsigned int i = 0; i < cornersBuffer.size(); i++ )
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{
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polyset_areas.Append( int( cornersBuffer[i].x * m_ScaleX ),
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int( cornersBuffer[i].y * m_ScaleY ) );
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}
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}
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else
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{
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// Add current hole in polyset_holes
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polyset_holes.NewOutline();
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|
for( unsigned int i = 0; i < cornersBuffer.size(); i++ )
|
|
{
|
|
polyset_holes.Append( int( cornersBuffer[i].x * m_ScaleX ),
|
|
int( cornersBuffer[i].y * m_ScaleY ) );
|
|
}
|
|
}
|
|
|
|
cornersBuffer.clear();
|
|
|
|
// at the end of a group of a positive path and its negative children, fill.
|
|
if( paths->next == nullptr || paths->next->sign == '+' )
|
|
{
|
|
polyset_areas.Simplify( SHAPE_POLY_SET::PM_STRICTLY_SIMPLE );
|
|
polyset_holes.Simplify( SHAPE_POLY_SET::PM_STRICTLY_SIMPLE );
|
|
polyset_areas.BooleanSubtract( polyset_holes, SHAPE_POLY_SET::PM_STRICTLY_SIMPLE );
|
|
|
|
// Ensure there are no self intersecting polygons
|
|
if( polyset_areas.NormalizeAreaOutlines() )
|
|
{
|
|
// Convert polygon with holes to a unique polygon
|
|
polyset_areas.Fracture( SHAPE_POLY_SET::PM_STRICTLY_SIMPLE );
|
|
|
|
// Output current resulting polygon(s)
|
|
for( int ii = 0; ii < polyset_areas.OutlineCount(); ii++ )
|
|
{
|
|
SHAPE_LINE_CHAIN& poly = polyset_areas.Outline( ii );
|
|
outputOnePolygon( poly, getBoardLayerName( aModLayer ));
|
|
}
|
|
|
|
polyset_areas.RemoveAllContours();
|
|
polyset_holes.RemoveAllContours();
|
|
main_outline = true;
|
|
}
|
|
}
|
|
|
|
paths = paths->next;
|
|
}
|
|
|
|
outputDataEnd();
|
|
}
|
|
|
|
// a helper function to calculate a square value
|
|
inline double square( double x )
|
|
{
|
|
return x * x;
|
|
}
|
|
|
|
|
|
// a helper function to calculate a cube value
|
|
inline double cube( double x )
|
|
{
|
|
return x * x * x;
|
|
}
|
|
|
|
|
|
/* render a Bezier curve. */
|
|
void BezierToPolyline( std::vector <potrace_dpoint_t>& aCornersBuffer,
|
|
potrace_dpoint_t p1,
|
|
potrace_dpoint_t p2,
|
|
potrace_dpoint_t p3,
|
|
potrace_dpoint_t p4 )
|
|
{
|
|
double dd0, dd1, dd, delta, e2, epsilon, t;
|
|
|
|
// p1 = starting point
|
|
|
|
/* we approximate the curve by small line segments. The interval
|
|
* size, epsilon, is determined on the fly so that the distance
|
|
* between the true curve and its approximation does not exceed the
|
|
* desired accuracy delta. */
|
|
|
|
delta = 0.25; /* desired accuracy, in pixels */
|
|
|
|
/* let dd = maximal value of 2nd derivative over curve - this must
|
|
* occur at an endpoint. */
|
|
dd0 = square( p1.x - 2 * p2.x + p3.x ) + square( p1.y - 2 * p2.y + p3.y );
|
|
dd1 = square( p2.x - 2 * p3.x + p4.x ) + square( p2.y - 2 * p3.y + p4.y );
|
|
dd = 6 * sqrt( std::max( dd0, dd1 ) );
|
|
e2 = 8 * delta <= dd ? 8 * delta / dd : 1;
|
|
epsilon = sqrt( e2 ); /* necessary interval size */
|
|
|
|
for( t = epsilon; t<1; t += epsilon )
|
|
{
|
|
potrace_dpoint_t intermediate_point;
|
|
intermediate_point.x = p1.x * cube( 1 - t ) +
|
|
3* p2.x* square( 1 - t ) * t +
|
|
3 * p3.x * (1 - t) * square( t ) +
|
|
p4.x* cube( t );
|
|
|
|
intermediate_point.y = p1.y * cube( 1 - t ) +
|
|
3* p2.y* square( 1 - t ) * t +
|
|
3 * p3.y * (1 - t) * square( t ) + p4.y* cube( t );
|
|
|
|
aCornersBuffer.push_back( intermediate_point );
|
|
}
|
|
|
|
aCornersBuffer.push_back( p4 );
|
|
}
|