Add weighted tx delay for flooding router

src/mesh/RadioLibInterface.cpp

@@ -113,7 +113,19 @@ ErrorCode RadioLibInterface::send(MeshPacket *p)
 
     // We want all sending/receiving to be done by our daemon thread, We use a delay here because this packet might have been sent
     // in response to a packet we just received.  So we want to make sure the other side has had a chance to reconfigure its radio
-    startTransmitTimer(true);
+
+    /* We assume if rx_snr = 0 and rx_rssi = 0, the packet was not generated locally.
+    *   This assumption is valid because of the offset generated by the radio to account for the noise
+    *   floor.
+    */  
+    if (p->rx_snr == 0 && p->rx_rssi == 0) {
+        startTransmitTimer(true);
+    } else {
+        // If there is a SNR, start a timer scaled based on that SNR.
+        DEBUG_MSG("rx_snr found. hop_limit:%d rx_snr:%f\n", p->hop_limit, p->rx_snr);
+        startTransmitTimerSNR(p->rx_snr);
+    }
+    
 
     return res;
 #else
@@ -208,6 +220,16 @@ void RadioLibInterface::startTransmitTimer(bool withDelay)
     }
 }
 
+void RadioLibInterface::startTransmitTimerSNR(float snr)
+{
+    // If we have work to do and the timer wasn't already scheduled, schedule it now
+    if (!txQueue.empty()) {
+        uint32_t delay = getTxDelayMsecWeighted(snr);
+        // DEBUG_MSG("xmit timer %d\n", delay);
+        notifyLater(delay, TRANSMIT_DELAY_COMPLETED, false); // This will implicitly enable
+    }
+}
+
 void RadioLibInterface::handleTransmitInterrupt()
 {
     // DEBUG_MSG("handling lora TX interrupt\n");