/**
* Perform the rewriting for the given number of generations.
* @param seed starting word
* @param numGenerations how many times to rewrite the word with our rules
* @return the nth-generation word
*/
public RenderQueue rewrite(RenderQueue seed, int numGenerations)
{
// Implementation is just to treat the seed as the "previous" output
// queue and then move the output queue to be the input queue for
// the next generation, apply the rules to any axioms for which we
// have rules (the other axioms are copied over to the output
// directly). Repeat this process for the given number of generations.
RenderQueue output = seed.copy();
RenderQueue input;
for (int gen = 0; gen < numGenerations; gen++)
{
input = output; // last generation's output is this one's input
output = new RenderQueue();
while (!input.empty())
{
RenderCommand nextInput = input.dequeue();
// look through the from-list to find a rule to invoke
bool ruleFound = false;
for (int i = 0; !ruleFound && i < from.Length; i++)
{
if (from[i] == nextInput)
{
ruleFound = true;
// append a copy of this rule's right side onto the
// end of the output queue
output.append(to[i]);
}
}
// if no rule was found, then just copy this command to output
if (!ruleFound)
{
output.enqueue(nextInput);
}
}
}
return(output);
}
