/// <summary>
/// Do nothing in this method as functions are not directly executed.
/// </summary>
public override bool Execute(ICanceller canceller)
{
if (canceller.ShouldCancel())
{
return false;
}
return true;
}
public TurtleGraphicsExecutionEngine(ITurtleGraphicsLexicalAnalyser textParser,
ITurtleGraphicsSyntaxAnalyser turtleGraphicsSyntaxAnalyser, ICanceller canceller,
ITurtleGraphicsRuntime turtleGraphicsRuntime)
{
_textParser = textParser;
_turtleGraphicsSyntaxAnalyser = turtleGraphicsSyntaxAnalyser;
_canceller = canceller;
_turtleGraphicsRuntime = turtleGraphicsRuntime;
}
/// <summary>
/// If commands are conditionally executed.
/// </summary>
public override bool Execute(ICanceller canceller)
{
if (canceller.ShouldCancel())
{
return false;
}
var shouldContinue = true;
if (ExpressionComparerHelper.CheckCondition(Lhs, Operator, Rhs))
{
shouldContinue = base.Execute(canceller);
}
return shouldContinue;
}
/// <summary>
/// Repeat commands are executed a fixed number of time.
/// </summary>
public override bool Execute(ICanceller canceller)
{
if (canceller.ShouldCancel())
{
return false;
}
var shouldContinue = true;
for (var iteration = 0; iteration < IterationCount; iteration++)
{
if (shouldContinue)
{
shouldContinue = base.Execute(canceller);
}
else
{
break;
}
}
return shouldContinue;
}
public SilverlightTurtleGraphicsRuntime(ICanceller canceller, Panel drawingSurface, Image turtlePointer, Color[] colors,
int startForeColorIdx, int startBackColorIdx, TextBox debugWindow, int initialPenWidth, ITurtleViewModel turtleViewModel,
ScrollViewer screenScroller)
{
_canceller = canceller;
_drawingSurface = drawingSurface;
_defaultTurtlePointer = turtlePointer;
_colors = colors;
_startForeColorIdx = startForeColorIdx;
_startBackColorIdx = startBackColorIdx;
_debugWindow = debugWindow;
_initialPenWidth = initialPenWidth;
_turtleViewModel = turtleViewModel;
_screenScroller = screenScroller;
_drawingSurface.Background = new SolidColorBrush();
InitialiseStructures();
SetInitialState();
SetUpColorConstants();
SetUpTurtleImageConstants();
}
/// <summary>
/// Halt execution or exit a function.
/// </summary>
public override bool Execute(ICanceller canceller)
{
return false;
}
/// <summary>
/// Executes the turtle graphics command and all nested commands, overridden in subclasses
/// to implemente execution behavior. For example loops and function will behave differently
/// </summary>
public virtual bool Execute(ICanceller canceller)
{
if(canceller.ShouldCancel())
{
return false;
}
var shouldContinue = true;
if (Attribute != null && Attribute.Type == typeof(TurtleGraphicsCommand))
{
ImplementingFunction.Invoke(ExecutionContext, ArgumentValues.Count == 0
? null
: GetTypedArgumentValues());
}
else if (Attribute != null && Attribute.Type == typeof(TurtleGraphicsDoFunctionCommand))
{
// Do function takes a param array so arguments need to be repackaged.
var argumentList = GetTypedArgumentValues();
var invokeList = new object[2];
invokeList[0] = argumentList[0];
var destinationArray = new float[argumentList.Length - 1];
Array.Copy(argumentList, 1, destinationArray, 0, argumentList.Length - 1);
invokeList[1] = destinationArray;
ImplementingFunction.Invoke(ExecutionContext, invokeList);
}
foreach (var innerCommand in Commands)
{
if (shouldContinue)
{
shouldContinue = innerCommand.Execute(canceller);
}
else
{
break;
}
}
return shouldContinue;
}
