Base working

Signed-off-by: Martyn Ranyard <m@rtyn.berlin>

main.go

@@ -0,0 +1,110 @@
+package main
+
+import (
+	"log"
+	"time"
+	"fmt"
+
+	"github.com/Hundemeier/go-sacn/sacn"
+)
+
+func slice_rearrange(rowwidth int, rows int, alternaterows bool, inslice []byte) [][]byte {
+	if alternaterows {
+		panic("Alternating rows not yet implemented")
+	}
+	currentUniverse := 0
+	currentUniversePosition := 0
+	universes := make([][]byte, (len(inslice)/510)+1)
+	currentUniverseSlice := make([]byte, 511)
+	currentRowReverse := false;
+	for i := range(inslice) {
+		fmt.Println(i)
+		if currentUniversePosition >= 510 {
+			fmt.Println("Reached end of universe!")
+			universes[currentUniverse] = currentUniverseSlice
+			if (!currentRowReverse) {
+				currentRowReverse = true
+			} else {
+				currentRowReverse = false
+			}
+			currentUniverse += 1
+			currentUniversePosition = 0
+			currentUniverseSlice = make([]byte, 511)
+		}
+		currentUniverseSlice[currentUniversePosition] = inslice[i]
+		currentUniversePosition += 1
+	}
+	universes[currentUniverse] = currentUniverseSlice
+  	return universes
+}
+
+// gradient returns from fromX to toX fading from (fromR,fromG,fromB) to (toR,toG,toB)
+// at least that's the idea.
+func gradient(fromR byte, fromG byte, fromB byte, toR byte, toG byte, toB byte, fromX int, toX int) []byte {
+	ret := make([]byte, toX*3);
+	var stepR float32 = (float32(toR) - float32(fromR)) / (float32(toX) - float32(fromX))
+	var stepG float32 = (float32(toG) - float32(fromG)) / (float32(toX) - float32(fromX))
+	var stepB float32 = (float32(toB) - float32(fromB)) / (float32(toX) - float32(fromX))
+	for i := fromX; i < toX*3; i+=3 {
+		ret[i] = fromR+byte(float32(i/3)*stepR)
+		ret[i+1] = fromG+byte(float32(i/3)*stepG)
+		ret[i+2] = fromB+byte(float32(i/3)*stepB)
+	}
+    return ret
+}
+
+func slice512(s []byte) [512]byte {
+	var ret [512]byte
+	for i := range(s) {
+		if i < 512 {
+			ret[i] = s[i]
+		}
+	}
+	return ret
+}
+
+func sliceUnlenthed(s [512]byte) []byte {
+	ret := make([]byte, 512);
+	for i := range(s) {
+		ret[i] = s[i]
+	}
+	return ret
+}
+
+func main() {
+	//instead of "" you could provide an ip-address that the socket should bind to
+	trans, err := sacn.NewTransmitter("", [16]byte{1, 2, 3}, "test")
+	if err != nil {
+		log.Fatal(err)
+	}
+	
+	//activates the first universe
+	ch1, err := trans.Activate(1)
+	if err != nil {
+		log.Fatal(err)
+	}
+	ch2, err := trans.Activate(2)
+	if err != nil {
+		log.Fatal(err)
+	}
+	//deactivate the channel on exit
+	defer close(ch1)
+	defer close(ch2)
+
+	//set a unicast destination, and/or use multicast
+	trans.SetMulticast(1, false)//this specific setup will not multicast on windows, 
+	//because no bind address was provided
+	
+	//set some example ip-addresses
+	trans.SetDestinations(1, []string{"192.168.1.139"})
+	trans.SetMulticast(2, false)//this specific setup will not multicast on windows, 
+	trans.SetDestinations(2, []string{"192.168.1.139"})
+	
+	//send some random data for 10 seconds
+	for i := 0; i < 20; i++ {
+		channels := slice_rearrange(68,4,false,gradient(0,0,255,255,0,0,0,272))
+		ch1 <- slice512(channels[0])
+		ch2 <- slice512(channels[1])
+		time.Sleep(500 * time.Millisecond)
+	}
+}