support for motor commands

sim/state/soundmotor.ts

@@ -1,5 +1,10 @@
 namespace pxsim.motors {
-    export function motorOn(power: number) {
+    export function motorPower(power: number) {
         // TODO
     }
+    export function motorCommand(command: MotorCommand) {
+
+    }
+    export function dualMotorPower(motor: Motor, percent: number) {
+    }
 }