start of a generic mutator system

[xonotic/xonotic-data.pk3dir.git] / qcsrc / server / mutators / base.qc

diff --git a/qcsrc/server/mutators/base.qc b/qcsrc/server/mutators/base.qc
new file mode 100644 (file)
index 0000000..0b1bea4
--- /dev/null
+++ b/qcsrc/server/mutators/base.qc
@@ -0,0 +1,108 @@
+.float() cbc_func;
+.entity cbc_next;
+.float cbc_order;
+
+entity CallbackChain_New(string name)
+{
+       entity e;
+       e = spawn();
+       e.classname = "callbackchain";
+       e.netname = name;
+       return e;
+}
+
+float CallbackChain_Add(entity cb, float() func, float order)
+{
+       entity e;
+       if(order & CBC_ORDER_FIRST)
+       {
+               if(order & CBC_ORDER_LAST)
+                       if(cb.cbc_order & CBC_ORDER_ANY)
+                               return 0;
+               if(cb.cbc_order & CBC_ORDER_FIRST)
+                       return 0;
+       }
+       else if(order & CBC_ORDER_LAST)
+       {
+               if(cb.cbc_order & CBC_ORDER_LAST)
+                       return 0;
+       }
+       entity thiscb;
+       thiscb = spawn();
+       thiscb.classname = "callback";
+       thiscb.cbc_func = func;
+       thiscb.cbc_order = order;
+       if(order & CBC_ORDER_FIRST)
+       {
+               thiscb.cbc_next = cb.cbc_next;
+               cb.cbc_next = thiscb;
+       }
+       else if(order & CBC_ORDER_LAST)
+       {
+               for(e = cb; e.cbc_next; e = e.cbc_next);
+               e.cbc_next = thiscb;
+       }
+       else
+       {
+               // by default we execute last, but before a possible CBC_ORDER_LAST callback
+               for(e = cb; e.cbc_next && !(e.cbc_next.cbc_order & CBC_ORDER_LAST); e = e.cbc_next); // we must make sure that we insert BEFORE an CBC_ORDER_LAST mutator!
+               thiscb.cbc_next = e.cbc_next;
+               e.cbc_next = thiscb;
+       }
+       cb.cbc_order |= (order | CBC_ORDER_ANY);
+       return 1;
+}
+
+float CallbackChain_Remove(entity cb, float() func)
+{
+       float order;
+       entity e;
+       float n;
+       n = 0;
+       for(e = cb; e.cbc_next; e = e.cbc_next)
+       {
+               while(e.cbc_next.cbc_func == func)
+               {
+                       // remove e.cbc_next from the chain
+                       entity e2;
+                       e2 = e.cbc_next.cbc_next;
+                       remove(e.cbc_next);
+                       e.cbc_next = e2;
+                       ++n;
+               }
+               // e.cbc_next is now something we want to keep
+               order |= (e.cbc_next.cbc_order & CBC_ORDER_ANY);
+       }
+       cb.cbc_order = order;
+       return n;
+}
+
+float CallbackChain_Call(entity cb)
+{
+       float r;
+       entity e;
+       r = 0;
+       for(e = cb; e.cbc_next; e = e.cbc_next)
+               r |= e.cbc_next.cbc_func();
+       return r; // callbacks return an error status, so 0 is default return value
+}
+
+float Mutator_Add(float(float) func)
+{
+       if(func(MUTATOR_ADDING) == 0)
+       {
+               // good
+               return 1;
+       }
+       backtrace("WARNING: when adding mutator: adding failed\n");
+       Mutator_Remove(func);
+       return 0;
+}
+void Mutator_Remove(float(float) func)
+{
+       if(func(MUTATOR_REMOVING) != 0)
+       {
+               // baaaaad
+               error("Mutator_Remove: removing mutator failed");
+       }
+}