clearance record improvements

        int     curTrackWidth = aBoard->m_BoardSettings->m_CurrentTrackWidth;

        int     curTrackWidth = aBoard->m_BoardSettings->m_CurrentTrackWidth;

        int     curTrackClear = aBoard->m_BoardSettings->m_TrackClearence;

        int     curTrackClear = aBoard->m_BoardSettings->m_TrackClearence;

        // The +5 is to give freerouter a little extra room, this is 0.5 mils.

        // The 0.5 is to give freerouter a little extra room, this is 0.5 mils.

        // If we export without this, then on import freerouter violates our

        // If we export without this, then on import freerouter violates our

        // DRC checks with track to via spacing, although this could be a

        // DRC checks with track to via spacing, although this could be a

        // result of > testing vs. >= testing in PCBNEW's DRC.

        // result of > testing vs. >= testing in PCBNEW's DRC.

        double  clearance = scale(curTrackClear+5);

//       double  safetyMargin = 0.5;

        // recent freerouter code adds .1 to the requested clearances, and I want .5

        // so subtract .1 so we actually get 0.5.

        double  safetyMargin = 0.4;

        double  clearance = scale(curTrackClear);

        STRINGS& rules = pcb->structure->rules->rules;

        STRINGS& rules = pcb->structure->rules->rules;

        sprintf( rule, "(width %.6g)", scale( curTrackWidth ) );

        sprintf( rule, "(width %.6g)", scale( curTrackWidth ) );

        rules.push_back( rule );

        rules.push_back( rule );

        sprintf( rule, "(clearance %.6g)", clearance );

        sprintf( rule, "(clearance %.6g)", clearance+safetyMargin );

        rules.push_back( rule );

        // On a high density board, a typical solder mask clearance will be 2-3 mils.

        // This exposes 2 to 3 mils of bare board around each pad.  So we need at least

        // 2 mils *extra* clearance for tracks which would come near a pad on

        // a different net.  So if the baseline trace to trace clearance was say 4 mils, then

        // the SMD to track clearance should be at least 6 mils.  Then, because

        // freerouter seems to be off about a 1/2 mil on clearance tests, add

        // another .5 mil for this test discrepancy as a safety margin.

        sprintf( rule, "(clearance %.6g (type default_smd))", clearance + safetyMargin + 2.0 );

        rules.push_back( rule );

        rules.push_back( rule );

        /* see: http://www.freerouting.net/usren/viewtopic.php?f=5&t=339#p474

        /* see: http://www.freerouting.net/usren/viewtopic.php?f=5&t=339#p474

        sprintf( rule, "(clearance %.6g (type pad_to_turn_gap))", clearance );

        sprintf( rule, "(clearance %.6g (type pad_to_turn_gap))", clearance + safetyMargin );

        rules.push_back( rule );

        rules.push_back( rule );

        sprintf( rule, "(clearance %.6g (type smd_to_turn_gap))", clearance );

        sprintf( rule, "(clearance %.6g (type smd_to_turn_gap))", clearance + safetyMargin );

        rules.push_back( rule );

        rules.push_back( rule );

        sprintf( rule, "(clearance %.6g (type via_via))", clearance );

        sprintf( rule, "(clearance %.6g (type via_via))", clearance + safetyMargin );

        rules.push_back( rule );

        rules.push_back( rule );

        sprintf( rule, "(clearance %.6g (type via_smd))", clearance );

        sprintf( rule, "(clearance %.6g (type via_smd))", clearance + safetyMargin );

        rules.push_back( rule );

        rules.push_back( rule );

        sprintf( rule, "(clearance %.6g (type via_pin))", clearance );

        sprintf( rule, "(clearance %.6g (type via_pin))", clearance + safetyMargin );

        rules.push_back( rule );

        rules.push_back( rule );

        sprintf( rule, "(clearance %.6g (type pin_pin))", clearance );

        sprintf( rule, "(clearance %.6g (type pin_pin))", clearance + safetyMargin );

        rules.push_back( rule );

        rules.push_back( rule );

        sprintf( rule, "(clearance %.6g (type smd_pin))", clearance );

        sprintf( rule, "(clearance %.6g (type smd_pin))", clearance + safetyMargin );

        rules.push_back( rule );

        rules.push_back( rule );

        */

        */

        // well, the user is going to text edit these in the DSN file anyway,

        // well, the user is going to text edit these in the DSN file anyway,

        // at least until we have an export dialog.

        // at least until we have an export dialog.

        // Pad to pad spacing on a single SMT part can be closer than our

        // clearance, we don't want freerouter complaining about that, so

        // output a significantly smaller pad to pad clearance to freerouter.

        clearance = scale(curTrackClear)/4;

        clearance = scale(curTrackClear)/4;

        sprintf( rule, "(clearance %.6g (type smd_smd))", clearance );

        sprintf( rule, "(clearance %.6g (type smd_smd))", clearance );