Disable real zipper from slipstream, but abuse the zipper timer to control

the effect duration. Global TODO: zipper / nitro / slipstream need each
a set of timer / engine power multiplier / speed limit, as well as
a fall off timer so they do not end sharply (maybe 1 sec transition
from raised speed limit to normal limit?).


git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/main/trunk@5381 178a84e3-b1eb-0310-8ba1-8eac791a3b58

src/karts/kart.cpp

@@ -908,11 +908,12 @@ float Kart::handleSlipstream(float dt)
     if(m_slipstream_time>m_kart_properties->getSlipstreamCollectTime())
     {
         m_slipstream_mode = SS_USE;
-        handleZipper();
-        return 0;
+        //handleZipper(); // FIXME(/REMOVE?) Zipper gives a sharp push, maybe too sharp
+        //return 0;       // see below about abusing m_zipper_time_left without zipper
         return m_kart_properties->getSlipstreamAddPower();
     }
-    return 0;
+    m_zipper_time_left = 5.0f; // FIXME, this is a hack to test higher speed limit without zipper, better would be own counter
+    return m_kart_properties->getSlipstreamAddPower();
 }   // handleSlipstream