kicad/pcbnew/zones_convert_brd_items_to_...

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/*******************************************/
/* zones_convert_brd_items_to_polygons.cpp */
/*******************************************/
/* Functions to convert some board items to polygons
* (pads, tracks ..)
* This is used to calculate filled areas in copper zones.
* Filled areas are areas remainder of the full zone area after removed all polygons
* calculated from these items shapes and the clearance area
*
* Important note:
* Because filled areas must have a minimum thickness to match with Design rule, they are draw in 2 step:
* 1 - filled polygons are drawn
* 2 - polygon outlines are drawn with a "minimum thickness width" ( or with a minimum thickness pen )
* So outlines of filled polygons are calculated with the constraint they match with clearance,
* taking in account outlines have thickness
* This ensures:
* - areas meet the minimum thickness requirement.
* - shapes are smoothed.
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*/
#include <math.h>
#include <vector>
#include "fctsys.h"
#include "common.h"
#include "pcbnew.h"
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#include "wxPcbStruct.h"
#include "trigo.h"
#include "zones.h"
#include "PolyLine.h"
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// Kbool 1.9 and before had sometimes problemes when calculating thermal shapes as polygons (this is the best solution)
// Kbool 2.0 has solved some problems, but not all
// Kbool 2.1 has solved some others problems, but not all
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// Used to create data files to debug Kbool
#include "debug_kbool_key_file_fct.h"
// Also we can create test files for Kbool bebug purposes
// when CREATE_KBOOL_KEY_FILES is defined
// See debug_kbool_key_file_fct.h
extern void BuildUnconnectedThermalStubsPolygonList( std::vector<CPolyPt>& aCornerBuffer,
BOARD* aPcb, ZONE_CONTAINER* aZone,
double aArcCorrection,
int aRoundPadThermalRotation);
extern void Test_For_Copper_Island_And_Remove( BOARD* aPcb,
ZONE_CONTAINER* aZone_container );
extern void CreateThermalReliefPadPolygon( std::vector<CPolyPt>& aCornerBuffer,
D_PAD& aPad,
int aThermalGap,
int aCopperThickness,
int aMinThicknessValue,
int aCircleToSegmentsCount,
double aCorrectionFactor,
int aThermalRot );
// Local Functions:
static void AddPolygonCornersToBoolengine( std::vector <CPolyPt>& aCornersBuffer,
Bool_Engine* aBoolengine, GroupType aGroup );
// Local Variables:
#ifdef CREATE_KBOOL_KEY_FILES_WITH_0_DEG
static int s_thermalRot = 0;
#else
static int s_thermalRot = 450; // angle of stubs in thermal reliefs for round pads
#endif
/* how many segments are used to create a polygon from a circle: */
static int s_CircleToSegmentsCount = ARC_APPROX_SEGMENTS_COUNT_LOW_DEF; /* default value. the real value will be changed to
* ARC_APPROX_SEGMENTS_COUNT_HIGHT_DEF
* if m_ArcToSegmentsCount == ARC_APPROX_SEGMENTS_COUNT_HIGHT_DEF
*/
double s_Correction; /* mult coeff used to enlarge rounded and oval pads (and vias)
* because the segment approximation for arcs and circles
* create a smaller gap than a true circle
*/
/**
* Function AddClearanceAreasPolygonsToPolysList
* Supports a min thickness area constraint.
* Add non copper areas polygons (pads and tracks with clearence)
* to the filled copper area found
* in BuildFilledPolysListData after calculating filled areas in a zone
* Non filled copper areas are pads and track and their clearance areas
* The filled copper area must be computed just before.
* BuildFilledPolysListData() call this function just after creating the
* filled copper area polygon (without clearence areas
* to do that this function:
* 1 - creates a Bool_Engine,with option: holes are linked to outer contours by double overlapping segments
* this means the created polygons have no holes (hole are linked to outer outline by double overlapped segments
* and are therefore compatible with draw functions (DC draw polygons and Gerber or PS outputs)
* 2 - Add the main outline (zone outline) in group A
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* 3 - Creates a correction using BOOL_CORRECTION operation to shrink the resulting area
* with m_ZoneMinThickness/2 value.
* The result is areas with a margin of m_ZoneMinThickness/2
* When drawing outline with segments having a thickness of m_ZoneMinThickness, the outlines will
* match exactly the initial outlines
* 4 - recreates the same Bool_Engine, with no correction
* 5 - Add the main modified outline (zone outline) in group A
* 6 - Add all non filled areas (pads, tracks) in group B with a clearance of m_Clearance + m_ZoneMinThickness/2
* 7 - calculates the polygon A - B
* 8 - put resulting list of polygons (filled areas) in m_FilledPolysList
* This zone contains pads with the same net.
* 9 - Remove insulated copper islands
* 10 - If Thermal shapes are wanted, remove copper around pads in zone, in order to create thes thermal shapes
* a - Creates a bool engine and add the last copper areas in group A
* b - Add thermal shapes (non copper ares in group B
* c - Calculates the polygon A - B
* 11 - Remove new insulated copper islands
*/
/* Important note:
* One can add thermal areas in the step 6, with others items to substract.
* It is faster.
* But :
* kbool fails sometimes in this case
* The separate step to make thermal shapes allows a more sophisticated algorith (todo)
* like remove thermal copper bridges in thermal shapes that are not connected to an area
*/
void ZONE_CONTAINER::AddClearanceAreasPolygonsToPolysList( BOARD* aPcb )
{
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// Set the number of segments in arc approximations
if( m_ArcToSegmentsCount == ARC_APPROX_SEGMENTS_COUNT_HIGHT_DEF )
s_CircleToSegmentsCount = ARC_APPROX_SEGMENTS_COUNT_HIGHT_DEF;
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else
s_CircleToSegmentsCount = ARC_APPROX_SEGMENTS_COUNT_LOW_DEF;
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/* calculates the coeff to compensate radius reduction of holes clearance
* due to the segment approx.
* For a circle the min radius is radius * cos( 2PI / s_CircleToSegmentsCount / 2)
* s_Correction is 1 /cos( PI/s_CircleToSegmentsCount )
*/
s_Correction = 1.0 / cos( 3.14159265 / s_CircleToSegmentsCount );
/* Uses a kbool engine to add holes in the m_FilledPolysList polygon.
* Because this function is called just after creating the m_FilledPolysList,
* only one polygon is in list.
* (initial holes in zones are linked into outer contours by double overlapping segments).
* because after adding holes, many polygons could be exist in this list.
*/
Bool_Engine* booleng = new Bool_Engine();
ArmBoolEng( booleng, true );
/* First, Add the main polygon (i.e. the filled area using only one outline)
* in GroupA in Bool_Engine to do a BOOL_CORRECTION operation
* to reserve a m_ZoneMinThickness/2 margind around the outlines and holes
* the margin will be filled when redraw outilnes with segments having a width set to
* m_ZoneMinThickness
* so m_ZoneMinThickness is the min thickness of the filled zones areas
*/
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CopyPolygonsFromFilledPolysListToBoolengine( booleng, GROUP_A );
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booleng->SetCorrectionFactor( (double) -m_ZoneMinThickness / 2 );
booleng->Do_Operation( BOOL_CORRECTION );
/* Now copy the new outline in m_FilledPolysList */
m_FilledPolysList.clear();
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CopyPolygonsFromBoolengineToFilledPolysList( booleng );
delete booleng;
if( m_FilledPolysList.size() == 0 )
return;
/* Second, Add the main (corrected) polygon (i.e. the filled area using only one outline)
* in GroupA in Bool_Engine to do a BOOL_A_SUB_B operation
* All areas to remove will be put in GroupB in Bool_Engine
*/
booleng = new Bool_Engine();
ArmBoolEng( booleng, true );
/* Calculates the clearance value that meet DRC requirements
* from m_ZoneClearance and clearance from the corresponding netclass
* We have a "local" clearance in zones because most of time
* clearance between a zone and others items is bigger than the netclass clearance
* this is more true for small clearance values
* Note also the "local" clearance is used for clearance between non copper items
* or items like texts on copper layers
*/
int margin = m_ZoneMinThickness / 2;
int zone_clearance = max( m_ZoneClearance, GetClearance() );
zone_clearance += margin;
/* Add holes (i.e. tracks and pads areas as polygons outlines)
* in GroupB in Bool_Engine
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*/
/* items ouside the zone bounding box are skipped
* the bounding box is the zone bounding box + the biggest clearance found in Netclass list
*/
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EDA_Rect item_boundingbox;
EDA_Rect zone_boundingbox = GetBoundingBox();
int biggest_clearance = aPcb->GetBiggestClearanceValue();
biggest_clearance = MAX( biggest_clearance, zone_clearance );
zone_boundingbox.Inflate( biggest_clearance );
#ifdef CREATE_KBOOL_KEY_FILES_FIRST_PASS
CreateKeyFile();
OpenKeyFileEntity( "Layer_fp" );
CopyPolygonsFromFilledPolysListToKeyFile( this, 0 );
#endif
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/*
* First : Add pads. Note: pads having the same net as zone are left in zone.
* Thermal shapes will be created later if necessary
*/
int item_clearance;
// static to avoid unnecessary memory allocation when filling many zones.
static std::vector <CPolyPt> cornerBufferPolysToSubstract;
cornerBufferPolysToSubstract.clear();
/* Use a dummy pad to calculate hole clerance when a pad is not on all copper layers
* and this pad has a hole
* This dummy pad has the size and shape of the hole
* Therefore, this dummy pad is a circle or an oval.
* A pad must have a parent because some functions expect a non null parent
* to find the parent board, and some other data
*/
MODULE dummymodule( aPcb ); // Creates a dummy parent
D_PAD dummypad( &dummymodule );
D_PAD* nextpad;
for( MODULE* module = aPcb->m_Modules; module; module = module->Next() )
{
for( D_PAD* pad = module->m_Pads; pad != NULL; pad = nextpad )
{
nextpad = pad->Next(); // pad pointer can be modified by next code, so calculate the next pad here
if( !pad->IsOnLayer( GetLayer() ) )
{
/* Test fo pads that are on top or bottom only and have a hole.
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* There are curious pads but they can be used for some components that are inside the
* board (in fact inside the hole. Some photo diodes and Leds are like this)
*/
if( (pad->m_Drill.x == 0) && (pad->m_Drill.y == 0) )
continue;
// Use a dummy pad to calculate a hole shape that have the same dimension as the pad hole
dummypad.m_Size = pad->m_Drill;
dummypad.m_Orient = pad->m_Orient;
dummypad.m_PadShape = pad->m_DrillShape;
dummypad.m_Pos = pad->m_Pos;
pad = &dummypad;
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}
if( pad->GetNet() != GetNet() )
{
item_clearance = pad->GetClearance() + margin;
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item_boundingbox = pad->GetBoundingBox();
if( item_boundingbox.Intersects( zone_boundingbox ) )
{
int clearance = MAX( zone_clearance, item_clearance );
pad->TransformShapeWithClearanceToPolygon( cornerBufferPolysToSubstract,
clearance,
s_CircleToSegmentsCount,
s_Correction );
}
continue;
}
int gap = zone_clearance;
if( (m_PadOption == PAD_NOT_IN_ZONE)
|| (GetNet() == 0) || pad->m_PadShape == PAD_TRAPEZOID )
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// PAD_TRAPEZOID shapes are not in zones because they are used in microwave apps
// and i think it is good that shapes are not changed by thermal pads or others
{
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item_boundingbox = pad->GetBoundingBox();
if( item_boundingbox.Intersects( zone_boundingbox ) )
{
pad->TransformShapeWithClearanceToPolygon( cornerBufferPolysToSubstract,
gap,
s_CircleToSegmentsCount,
s_Correction );
}
}
}
}
/* Add holes (i.e. tracks and vias areas as polygons outlines)
* in cornerBufferPolysToSubstract
*/
for( TRACK* track = aPcb->m_Track; track; track = track->Next() )
{
if( !track->IsOnLayer( GetLayer() ) )
continue;
if( track->GetNet() == GetNet() && (GetNet() != 0) )
continue;
item_clearance = track->GetClearance() + margin;
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item_boundingbox = track->GetBoundingBox();
if( item_boundingbox.Intersects( zone_boundingbox ) )
{
int clearance = MAX( zone_clearance, item_clearance );
track->TransformShapeWithClearanceToPolygon( cornerBufferPolysToSubstract,
clearance,
s_CircleToSegmentsCount,
s_Correction );
}
}
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/* Add module edge items that are on copper layers
* Pcbnew allows these items to be on copper layers in microwvae applictions
* This is a bad thing, but must be handle here, until a better way is found
*/
for( MODULE* module = aPcb->m_Modules; module; module = module->Next() )
{
for( BOARD_ITEM* item = module->m_Drawings; item; item = item->Next() )
{
if( !item->IsOnLayer( GetLayer() ) )
continue;
if( item->Type() != TYPE_EDGE_MODULE )
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continue;
item_boundingbox = item->GetBoundingBox();
if( item_boundingbox.Intersects( zone_boundingbox ) )
{
( (EDGE_MODULE*) item )->TransformShapeWithClearanceToPolygon(
cornerBufferPolysToSubstract, m_ZoneClearance,
s_CircleToSegmentsCount, s_Correction );
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}
}
}
// Add graphic items (copper texts) and board edges
for( BOARD_ITEM* item = aPcb->m_Drawings; item; item = item->Next() )
{
if( item->GetLayer() != GetLayer() && item->GetLayer() != EDGE_N )
continue;
switch( item->Type() )
{
case TYPE_DRAWSEGMENT:
( (DRAWSEGMENT*) item )->TransformShapeWithClearanceToPolygon(
cornerBufferPolysToSubstract,
m_ZoneClearance,
s_CircleToSegmentsCount,
s_Correction );
break;
case TYPE_TEXTE:
( (TEXTE_PCB*) item )->TransformShapeWithClearanceToPolygon(
cornerBufferPolysToSubstract,
m_ZoneClearance,
s_CircleToSegmentsCount,
s_Correction );
break;
default:
break;
}
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}
// cornerBufferPolysToSubstract contains polygons to substract,
// prepare booleng to do that:
AddPolygonCornersToBoolengine( cornerBufferPolysToSubstract,
booleng, GROUP_B );
#ifdef CREATE_KBOOL_KEY_FILES_FIRST_PASS
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for( unsigned icnt = 0; icnt < cornerBuffer.size(); )
{
StartKeyFilePolygon( 1 );
for( ii = icnt; ii < cornerBuffer.size(); ii++ )
{
AddKeyFilePointXY( cornerBufferPolysToSubstract[ii].x,
cornerBufferPolysToSubstract[ii].y );
if( cornerBufferPolysToSubstract[ii].end_contour )
break;
}
EndKeyFilePolygon();
icnt = ii + 1;
}
CloseKeyFileEntity();
CloseKeyFile();
#endif
/* calculates copper areas */
if( cornerBufferPolysToSubstract.size() > 0 )
{
/* Add the main corrected polygon (i.e. the filled area using only one outline)
* in GroupA in Bool_Engine
*/
CopyPolygonsFromFilledPolysListToBoolengine( booleng, GROUP_A );
booleng->Do_Operation( BOOL_A_SUB_B );
/* put these areas in m_FilledPolysList */
m_FilledPolysList.clear();
CopyPolygonsFromBoolengineToFilledPolysList( booleng );
}
delete booleng;
// Remove insulated islands:
if( GetNet() > 0 )
Test_For_Copper_Island_And_Remove_Insulated_Islands( aPcb );
// remove thermal gaps if required:
if( m_PadOption != THERMAL_PAD || aPcb->m_Modules == NULL )
return;
// Remove thermal symbols
cornerBufferPolysToSubstract.clear();
if( m_PadOption == THERMAL_PAD )
{
booleng = new Bool_Engine();
ArmBoolEng( booleng, true );
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#ifdef CREATE_KBOOL_KEY_FILES
CreateKeyFile();
OpenKeyFileEntity( "Layer" );
CopyPolygonsFromFilledPolysListToKeyFile( this, 0 );
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#endif
for( MODULE* module = aPcb->m_Modules; module; module = module->Next() )
{
for( D_PAD* pad = module->m_Pads; pad != NULL; pad = pad->Next() )
{
if( !pad->IsOnLayer( GetLayer() ) )
continue;
if( pad->GetNet() != GetNet() )
continue;
item_boundingbox = pad->GetBoundingBox();
item_boundingbox.Inflate( m_ThermalReliefGapValue );
if( item_boundingbox.Intersects( zone_boundingbox ) )
{
CreateThermalReliefPadPolygon( cornerBufferPolysToSubstract,
*pad, m_ThermalReliefGapValue,
m_ThermalReliefCopperBridgeValue,
m_ZoneMinThickness,
s_CircleToSegmentsCount,
s_Correction, s_thermalRot );
}
}
}
if( cornerBufferPolysToSubstract.size() )
{
/* Add the main corrected polygon (i.e. the filled area using only one outline)
* in GroupA in Bool_Engine
*/
CopyPolygonsFromFilledPolysListToBoolengine( booleng, GROUP_A );
// cornerBufferPolysToSubstract contains polygons to substract,
// prepare booleng to do that:
AddPolygonCornersToBoolengine( cornerBufferPolysToSubstract,
booleng, GROUP_B );
/* remove thermal areas (non copper areas) */
booleng->Do_Operation( BOOL_A_SUB_B );
/* put these areas in m_FilledPolysList */
m_FilledPolysList.clear();
CopyPolygonsFromBoolengineToFilledPolysList( booleng );
}
delete booleng;
// Remove insulated islands:
if( GetNet() > 0 )
Test_For_Copper_Island_And_Remove_Insulated_Islands( aPcb );
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#ifdef CREATE_KBOOL_KEY_FILES
for( unsigned icnt = 0; icnt < cornerBufferPolysToSubstract.size(); )
{
StartKeyFilePolygon( 1 );
for( ii = icnt; ii < cornerBufferPolysToSubstract.size(); ii++ )
{
AddKeyFilePointXY( cornerBufferPolysToSubstract[ii].x,
cornerBufferPolysToSubstract[ii].y );
if( cornerBufferPolysToSubstract[ii].end_contour )
break;
}
EndKeyFilePolygon();
icnt = ii + 1;
}
}
CloseKeyFileEntity();
CloseKeyFile();
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#endif
}
// Now we remove all unused thermal stubs.
#define REMOVE_UNUSED_THERMAL_STUBS // Can be commented to skip unused thermal stubs calculations
#ifdef REMOVE_UNUSED_THERMAL_STUBS
// Test thermal stubs connections and add polygons to remove unconnected stubs.
booleng = new Bool_Engine();
ArmBoolEng( booleng, true );
cornerBufferPolysToSubstract.clear();
BuildUnconnectedThermalStubsPolygonList( cornerBufferPolysToSubstract, aPcb, this, s_Correction, s_thermalRot );
/* remove copper areas */
if( cornerBufferPolysToSubstract.size() )
{
/* Add the main corrected polygon (i.e. the filled area using only one outline)
* in GroupA in Bool_Engine
*/
CopyPolygonsFromFilledPolysListToBoolengine( booleng, GROUP_A );
AddPolygonCornersToBoolengine( cornerBufferPolysToSubstract, booleng, GROUP_B );
booleng->Do_Operation( BOOL_A_SUB_B );
/* put these areas in m_FilledPolysList */
m_FilledPolysList.clear();
CopyPolygonsFromBoolengineToFilledPolysList( booleng );
// Remove insulated islands, if any:
if( GetNet() > 0 )
Test_For_Copper_Island_And_Remove_Insulated_Islands( aPcb );
}
delete booleng;
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#endif // REMOVE_UNUSED_THERMAL_STUBS
}
/** AddPolygonCornersToBoolengine
* copy a set of polygons in a kbool engine
* @param aCornersBuffer = list of polygons defined by corners.
* @ param aBoolengine = the kbool engine to populate
* @ param aGroup = GROUP_A or GROUP_B
*/
void AddPolygonCornersToBoolengine( std::vector <CPolyPt>& aCornersBuffer,
Bool_Engine* aBoolengine, GroupType aGroup )
{
unsigned ii;
for( unsigned icnt = 0; icnt < aCornersBuffer.size(); )
{
aBoolengine->StartPolygonAdd( aGroup );
for( ii = icnt; ii < aCornersBuffer.size(); ii++ )
{
aBoolengine->AddPoint( aCornersBuffer[ii].x, aCornersBuffer[ii].y );
if( aCornersBuffer[ii].end_contour )
break;
}
aBoolengine->EndPolygonAdd();
icnt = ii + 1;
}
}
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/***********************************************************************************************************/
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int ZONE_CONTAINER::CopyPolygonsFromFilledPolysListToBoolengine( Bool_Engine* aBoolengine,
GroupType aGroup )
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/************************************************************************************************************/
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/**
* Function CopyPolygonsFromFilledPolysListToBoolengine
* Copy (Add) polygons found in m_FilledPolysList to kbool BoolEngine
* m_FilledPolysList may have more than one polygon
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* @param aBoolengine = kbool engine
* @param aGroup = group in kbool engine (GROUP_A or GROUP_B only)
* @return the corner count
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*/
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{
unsigned corners_count = m_FilledPolysList.size();
int count = 0;
unsigned ic = 0;
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while( ic < corners_count )
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{
if( aBoolengine->StartPolygonAdd( aGroup ) )
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{
for( ; ic < corners_count; ic++ )
{
CPolyPt* corner = &m_FilledPolysList[ic];
aBoolengine->AddPoint( corner->x, corner->y );
count++;
if( corner->end_contour )
{
ic++;
break;
}
}
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aBoolengine->EndPolygonAdd();
}
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}
return count;
}
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/*****************************************************************************************/
int ZONE_CONTAINER::CopyPolygonsFromBoolengineToFilledPolysList( Bool_Engine* aBoolengine )
/*****************************************************************************************/
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/**
* Function CopyPolygonsFromBoolengineToFilledPolysList
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* Copy (Add) polygons created by kbool (after Do_Operation) to m_FilledPolysList
* @param aBoolengine = kbool engine
* @return the corner count
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*/
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{
int count = 0;
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while( aBoolengine->StartPolygonGet() )
{
CPolyPt corner( 0, 0, false );
while( aBoolengine->PolygonHasMorePoints() )
{
corner.x = (int) aBoolengine->GetPolygonXPoint();
corner.y = (int) aBoolengine->GetPolygonYPoint();
corner.end_contour = false;
// Flag this corner if starting a hole connection segment:
// This is used by draw functions to draw only useful segments (and not extra segments)
corner.utility = (aBoolengine->GetPolygonPointEdgeType() == KB_FALSE_EDGE) ? 1 : 0;
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m_FilledPolysList.push_back( corner );
count++;
}
corner.end_contour = true;
m_FilledPolysList.pop_back();
m_FilledPolysList.push_back( corner );
aBoolengine->EndPolygonGet();
}
return count;
}