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diff --git a/Stars45/Shield.cpp b/Stars45/Shield.cpp
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+/*  Starshatter OpenSource Distribution
+    Copyright (c) 1997-2004, Destroyer Studios LLC.
+    All Rights Reserved.
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright notice,
+      this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above copyright notice,
+      this list of conditions and the following disclaimer in the documentation
+      and/or other materials provided with the distribution.
+    * Neither the name "Destroyer Studios" nor the names of its contributors
+      may be used to endorse or promote products derived from this software
+      without specific prior written permission.
+
+    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+    AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+    ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+    LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+    CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+    SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+    INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+    CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+    ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+    POSSIBILITY OF SUCH DAMAGE.
+
+    SUBSYSTEM:    Stars.exe
+    FILE:         Shield.cpp
+    AUTHOR:       John DiCamillo
+
+
+    OVERVIEW
+    ========
+    Weapon class
+*/
+
+#include "MemDebug.h"
+#include "Shield.h"
+#include "Shot.h"
+#include "WeaponDesign.h"
+
+#include "Game.h"
+
+// +----------------------------------------------------------------------+
+
+static char*   shield_name[] = {
+    "sys.shield.none",
+    "sys.shield.deflector",
+    "sys.shield.grav",
+    "sys.shield.hyper"
+};
+
+static int     shield_value[] = {
+    0, 2, 2, 3
+};
+
+// +----------------------------------------------------------------------+
+
+Shield::Shield(SUBTYPE shield_type)
+: System(SHIELD, shield_type, "shield", shield_value[shield_type], 100, 0),
+shield_cutoff(0.0f), shield_capacitor(false), shield_bubble(false),
+deflection_cost(1.0f), shield_curve(0.05f)
+{
+    name = Game::GetText(shield_name[shield_type]);
+    abrv = Game::GetText("sys.shield.abrv");
+
+    power_flags  = POWER_WATTS | POWER_CRITICAL;
+    energy       = 0.0f;
+    power_level  = 0.0f;
+    shield_level = 0.0f;
+
+    switch (shield_type) {
+    default:
+    case DEFLECTOR:
+        capacity = sink_rate = 2.0e3f;
+        shield_factor        = 0.05f;
+        break;
+
+    case GRAV_SHIELD:
+        capacity = sink_rate = 7.0e3f;
+        shield_factor        = 0.01f;
+        break;
+
+    case HYPER_SHIELD:
+        capacity = sink_rate = 10.0e3f;
+        shield_factor        = 0.003f;
+        break;
+    }
+
+    emcon_power[0] = 0;
+    emcon_power[1] = 0;
+    emcon_power[2] = 100;
+}
+
+// +----------------------------------------------------------------------+
+
+Shield::Shield(const Shield& s)
+: System(s), shield_factor(s.shield_factor), requested_power_level(0.0f),
+shield_cutoff(s.shield_cutoff), shield_capacitor(s.shield_capacitor),
+shield_bubble(s.shield_bubble), deflection_cost(s.deflection_cost),
+shield_curve(s.shield_curve)
+{
+    power_flags  = s.power_flags;
+    energy       = 0.0f;
+    power_level  = 0.0f;
+    shield_level = 0.0f;
+
+    Mount(s);
+}
+
+// +--------------------------------------------------------------------+
+
+Shield::~Shield()
+{ }
+
+void
+Shield::SetShieldCapacitor(bool c)
+{
+    shield_capacitor = c;
+
+    if (shield_capacitor) {
+        power_flags = POWER_CRITICAL;
+        shield_curve = 0.05f;
+    }
+    else {
+        power_flags = POWER_WATTS | POWER_CRITICAL;
+        shield_curve = 0.25f;
+    }
+}
+
+// +--------------------------------------------------------------------+
+
+void
+Shield::ExecFrame(double seconds)
+{
+    System::ExecFrame(seconds);
+
+    if (power_level < requested_power_level) {
+        power_level += (float) (seconds * 0.10);     // ten seconds to charge up
+
+        if (power_level > requested_power_level)
+        power_level = (float) requested_power_level;
+    }
+    else if (power_level > requested_power_level) {
+        power_level -= (float) (seconds * 0.20);     // five seconds to power down
+
+        if (power_level < requested_power_level)
+        power_level = (float) requested_power_level;
+    }
+
+    if (power_level < 0.01 && !shield_capacitor) {
+        shield_level = 0.0f;
+        energy       = 0.0f;
+    }
+}
+
+// +----------------------------------------------------------------------+
+
+void
+Shield::Distribute(double delivered_energy, double seconds)
+{
+    System::Distribute(delivered_energy, seconds);
+
+    if (shield_capacitor) {
+        if (shield_cutoff > 0 && shield_cutoff < 0.999) {
+            float cutoff = shield_cutoff * capacity;
+
+            if (energy > cutoff)
+            shield_level = (energy-cutoff)/(capacity-cutoff);
+            else
+            shield_level = 0.0f;
+        }
+
+        else {
+            shield_level = energy/capacity;
+        }
+    }
+    else {
+        shield_level = energy/sink_rate;
+        energy       = 0.0f;
+    }
+
+    if (shield_level < 0)
+    shield_level = 0;
+}
+
+// +--------------------------------------------------------------------+
+
+double
+Shield::DeflectDamage(Shot* shot, double damage)
+{
+    double filter      = 1;
+    double penetration = 5;
+    double leak        = 0;
+
+    if (shot)
+    penetration = shot->Design()->penetration;
+
+    filter = 1 - shield_factor * penetration;
+
+    if (filter < 0)
+    filter = 0;
+
+    else if (filter > 1)
+    filter = 1;
+
+    if (shield_capacitor) {
+        if (shield_cutoff > 0 && shield_level < 1e-6) {
+            leak = damage;
+            energy -= (float) (damage * deflection_cost);
+        }
+
+        else {
+            leak = damage * (1 - pow(shield_level, shield_curve) * filter * availability);
+
+            double deflected = damage - leak;
+            energy -= (float) deflected * deflection_cost;
+        }
+
+    }
+    else {
+        leak = damage * (1 - pow(shield_level, shield_curve) * filter * availability);
+    }
+
+    return leak;
+}
+
+// +--------------------------------------------------------------------+
+
+void
+Shield::SetPowerLevel(double level)
+{
+    if (level > 100)
+    level = 100;
+    else if (level < 0)
+    level = 0;
+
+    level /= 100;
+
+    if (requested_power_level != level) {
+        // if the system is on emergency override power,
+        // do not let the EMCON system use this method
+        // to drop it back to normal power:
+        if (power_level > 1 && level == 1) {
+            requested_power_level = (float) power_level;
+            return;
+        }
+
+        requested_power_level = (float) level;
+    }
+}
+
+void
+Shield::SetNetShieldLevel(int level)
+{
+    if (level > 100)     level = 100;
+    else if (level < 0)  level =   0;
+
+    requested_power_level = (float) (level/100.0);
+    power_level           = requested_power_level;
+}
+
+void
+Shield::DoEMCON(int index)
+{
+    int e = GetEMCONPower(index);
+
+    if (power_level * 100 > e || emcon != index) {
+        if (e == 0) {
+            PowerOff();
+        }
+        else if (emcon != index) {
+            PowerOn();
+
+            if (power_level * 100 > e)
+            SetPowerLevel(e);
+        }
+    }
+
+    emcon = index;
+}