Various AI fixes / improvements

[TobiasKarnat]

Only let AI build buildings, infantry and units the tech tree allows

diff -urN a/redalert/base.cpp b/redalert/base.cpp
--- a/redalert/base.cpp 2020-09-24 17:38:00.856284099 +0200
+++ b/redalert/base.cpp 2020-09-24 17:38:21.275670503 +0200
@@ -386,7 +386,7 @@
         ** For STRUCT_NONE, return the first hole found
         */
         if (type == STRUCT_NONE) {
-            if (!Is_Built(i)) {
+            if (BuildingTypeClass::As_Reference(Nodes[i].Type).Level != -1 && !Is_Built(i)) {
                 return (&Nodes[i]);
             }

diff -urN a/tiberiandawn/base.cpp b/tiberiandawn/base.cpp
--- a/tiberiandawn/base.cpp 2020-09-24 17:38:00.816283342 +0200
+++ b/tiberiandawn/base.cpp 2020-09-24 17:38:21.276670521 +0200
@@ -481,7 +481,7 @@
         ** For STRUCT_NONE, return the first hole found
         */
         if (type == STRUCT_NONE) {
-            if (!Is_Built(i)) {
+            if (BuildingTypeClass::As_Reference(Nodes[i].Type).IsBuildable && !Is_Built(i)) {
                 return (&Nodes[i]);
             }

diff -urN a/tiberiandawn/house.cpp b/tiberiandawn/house.cpp
--- a/tiberiandawn/house.cpp    2020-09-24 17:38:00.840283796 +0200
+++ b/tiberiandawn/house.cpp    2020-09-24 17:38:21.281670616 +0200
@@ -3724,8 +3724,7 @@
             int bestcount = 0;
             UnitType bestlist[UNIT_COUNT];
             for (UnitType utype = UNIT_FIRST; utype < UNIT_COUNT; utype++) {
-                if (counter[utype] > 0 && Can_Build(utype, Class->House)
-                    && UnitTypeClass::As_Reference(utype).Cost_Of() <= Available_Money()) {
+                if (counter[utype] > 0 && UnitTypeClass::As_Reference(utype).Who_Can_Build_Me(false, false, Class->House) && UnitTypeClass::As_Reference(utype).Cost_Of() <= Available_Money()) {
                     if (bestval == -1 || bestval < counter[utype]) {
                         bestval = counter[utype];
                         bestcount = 0;
@@ -3826,8 +3825,7 @@
             int bestcount = 0;
             InfantryType bestlist[INFANTRY_COUNT];
             for (InfantryType utype = INFANTRY_FIRST; utype < INFANTRY_COUNT; utype++) {
-                if (counter[utype] > 0 && Can_Build(utype, Class->House)
-                    && InfantryTypeClass::As_Reference(utype).Cost_Of() <= Available_Money()) {
+                if (counter[utype] > 0 && InfantryTypeClass::As_Reference(utype).Who_Can_Build_Me(false, false, Class->House) && InfantryTypeClass::As_Reference(utype).Cost_Of() <= Available_Money()) {
                     if (bestval == -1 || bestval < counter[utype]) {
                         bestval = counter[utype];
                         bestcount = 0;

Give the AI the same speed bonus for multiple factories as the human player [TD]

diff -urN a/tiberiandawn/factory.cpp b/tiberiandawn/factory.cpp
--- a/tiberiandawn/factory.cpp  2020-09-24 17:38:00.823283475 +0200
+++ b/tiberiandawn/factory.cpp  2020-09-24 17:38:21.276670521 +0200
@@ -228,11 +228,8 @@

         /*
         ** Determine the acceleration factor for factory production.
-        ** This applies only to human players. The computer builds
-        ** units on a building by building basis -- quantity of building
-        ** factory types doesn't affect individual factories.
         */
-        if (Object && House->IsHuman) {
+        if (Object) {
             switch (Object->What_Am_I()) {
             case RTTI_AIRCRAFT:
                 stages = House->AircraftFactories;

Fix spelling error to allow discovered enemy objects to go into hunt mode

diff -urN a/redalert/techno.cpp b/redalert/techno.cpp
--- a/redalert/techno.cpp   2020-10-15 18:57:03.525696597 +0200
+++ b/redalert/techno.cpp   2020-10-15 18:57:38.768162149 +0200
@@ -774,7 +774,7 @@
         ** An enemy object that is discovered will go into hunt mode if
         ** its current mission is to ambush.
         */
-        if (!house->IsHuman && Mission == MISSION_AMBUSH) {
+        if (!House->IsHuman && Mission == MISSION_AMBUSH) {
             Assign_Mission(MISSION_HUNT);
         }

diff -urN a/tiberiandawn/techno.cpp b/tiberiandawn/techno.cpp
--- a/tiberiandawn/techno.cpp   2020-10-15 18:57:03.530696663 +0200
+++ b/tiberiandawn/techno.cpp   2020-10-15 18:58:07.586547972 +0200
@@ -549,7 +549,7 @@
         ** An enemy object that is discovered will go into hunt mode if
         ** its current mission is to ambush.
         */
-        if (!house->IsHuman && Mission == MISSION_AMBUSH) {
+        if (!House->IsHuman && Mission == MISSION_AMBUSH) {
             Assign_Mission(MISSION_HUNT);
         }

[mvdhout1992]

The "Only let AI build buildings, infantry and units the tech tree allows" will break custom missions and maybe some official maps. Some Aftermath/Counterstrike missions have the AI built buildings via [Base] that they can't normally build.

[TobiasKarnat]

Which ones? I played through all Aftermath/Counterstrike missions actually again without noticing a bug.

This change is primarily for TD, it is just annoying that the AI can just rebuild the construction yard.

[mvdhout1992]

Try the Gargnev Revolution mission, on the bottom left there are mixed arms yellow buildings. Brothers in Arms too. Note that you need to check them rebuilding the buildings.

[hifi]

If these changes make skirmish more enjoyable we could include these behind a rules flag in the skirmish window that is enabled by default.

We must not change how the original campaign plays.

[TobiasKarnat]

None of the buildings get rebuild in Gargnev Revolution even without this patch in the original version (maybe a bug itself?).

I think making it an option even for original campaign would be good.

[Nyerguds]

In C&C1 this is specifically intended. Look at the Covert Ops mission "Blackout" for a very specific example of a second construction yard only scripted to get built later in the mission.