/*
* Align elements horizontally and return a canvas.
* Elements include Canvas and MathText.
*/
public AlignCanvas ArrangeHorizontalGroup(params FrameworkElement[] elements)
{
AlignCanvas board = new AlignCanvas();
// maxAlignDepth: the max depth from the top, where all nodes are to be aligned
double startWidth = 0, maxAlignDepth = 0;
// set each element's left margin
foreach (var element in elements)
{
AlignCanvas.SetLeft(element, startWidth);
if (element is MathText)
{
element.Measure(new Size(Double.PositiveInfinity, Double.PositiveInfinity));
startWidth += element.DesiredSize.Width;
if (maxAlignDepth < element.DesiredSize.Height / 2)
{
maxAlignDepth = element.DesiredSize.Height / 2;
}
}
else
{
// it's a canvas.
startWidth += element.Width;
if (maxAlignDepth < (element as AlignCanvas).alignHeight)
{
maxAlignDepth = (element as AlignCanvas).alignHeight;
}
}
}
// set each element's top margin
double maxDepth = 0;
foreach (var element in elements)
{
if (element is MathText)
{
AlignCanvas.SetTop(element, maxAlignDepth - element.DesiredSize.Height / 2);
if (element.DesiredSize.Height + maxAlignDepth - element.DesiredSize.Height / 2 > maxDepth)
{
maxDepth = element.DesiredSize.Height + maxAlignDepth - element.DesiredSize.Height / 2;
}
}
else
{
AlignCanvas.SetTop(element, maxAlignDepth - (element as AlignCanvas).alignHeight);
if (element.Height + maxAlignDepth - (element as AlignCanvas).alignHeight > maxDepth)
{
maxDepth = element.Height + maxAlignDepth - (element as AlignCanvas).alignHeight;
}
}
board.Children.Add(element);
}
board.Width = startWidth;
board.Height = maxDepth;
board.alignHeight = maxAlignDepth;
return(board);
}
public AlignCanvas ArrangeVerticalGroup(params FrameworkElement[] elements)
{
AlignCanvas board = new AlignCanvas();
double startDepth = 0, maxWidth = 0;
// set each element's left margin
foreach (var element in elements)
{
AlignCanvas.SetTop(element, startDepth);
if (element is Rectangle) // fraction bar
{
board.alignHeight = startDepth;
}
if (element is MathText)
{
element.Measure(new Size(Double.PositiveInfinity, Double.PositiveInfinity));
startDepth += element.DesiredSize.Height;
if (maxWidth < element.DesiredSize.Width)
{
maxWidth = element.DesiredSize.Width;
}
}
else
{
// it's a canvas or sth like that.
startDepth += element.Height;
if (maxWidth < element.Width)
{
maxWidth = element.Width;
}
}
}
// set each element's top margin
foreach (var element in elements)
{
if (element is MathText)
{
AlignCanvas.SetLeft(element, (maxWidth - element.DesiredSize.Width) / 2);
}
else
{
AlignCanvas.SetLeft(element, (maxWidth - element.Width) / 2);
}
board.Children.Add(element);
}
board.Height = startDepth;
board.Width = maxWidth;
if (board.alignHeight == 0)
{
board.alignHeight = startDepth;
}
return(board);
}
public AlignCanvas RenderElement(Calc_node exp, double fontsize = defaultFontSize)
{
AlignCanvas board = null;
if (exp is Value_node)
{
MathText text = null;
if (exp.isint)
{
text = new MathText(exp.result.ToString(), fontsize);
}
else
{
text = new MathText(exp.fresult.ToString(), fontsize);
}
board = ArrangeHorizontalGroup(text);
// board.alignHeight = text.DesiredSize.Height;
}
else if (exp is Bracket_node)
{
// we separate brackets and inner text
MathText lparen = new MathText("(", fontsize);
AlignCanvas inner_text = RenderElement((exp as Bracket_node).internal_node, fontsize);
MathText rparen = new MathText(")", fontsize);
// arrange positions of these elements
board = ArrangeHorizontalGroup(lparen, inner_text, rparen);
}
else if (exp is Binary_node)
{
AlignCanvas operand1 = null, operand2 = null;
switch ((exp as Binary_node).op)
{
// horizontal expressions
case Binary_node.Operator.ADD:
case Binary_node.Operator.MINUS:
case Binary_node.Operator.MULTI:
operand1 = RenderElement((exp as Binary_node).node1, fontsize);
MathText add = new MathText(opID[(int)(exp as Binary_node).op], fontsize);
operand2 = RenderElement((exp as Binary_node).node2, fontsize);
board = ArrangeHorizontalGroup(operand1, add, operand2);
break;
// vertical expressions
case Binary_node.Operator.DIVIDE:
operand1 = RenderElement((exp as Binary_node).node1, fontsize * shrinkRatio);
operand2 = RenderElement((exp as Binary_node).node2, fontsize * shrinkRatio);
// strip the bracket if operand2 is a bracket node
if (operand2.Children.Count == 3 && operand2.Children[0] is MathText && operand2.Children[2] is MathText)
{
AlignCanvas inner_node = operand2.Children[1] as AlignCanvas;
operand2.Children.Remove(inner_node);
operand2 = inner_node;
}
Rectangle fractline = new Rectangle();
// fractline's width should be the longer of two elements
fractline.Width = (operand1.Width > operand2.Width ? operand1.Width : operand2.Width) * 1.1;
fractline.Height = fractionBarHeight;
fractline.Fill = System.Windows.Media.Brushes.Black;
fractline.HorizontalAlignment = HorizontalAlignment.Center;
board = ArrangeVerticalGroup(operand1, fractline, operand2);
break;
// miscellaneous
case Binary_node.Operator.EXPO:
operand1 = RenderElement((exp as Binary_node).node1, fontsize);
operand2 = RenderElement((exp as Binary_node).node2, fontsize * expoRatio);
board = new AlignCanvas();
Canvas.SetTop(operand1, operand2.Height / 2);
Canvas.SetLeft(operand1, 0);
board.Children.Add(operand1);
Canvas.SetTop(operand2, 0);
Canvas.SetLeft(operand2, operand1.Width);
board.Children.Add(operand2);
board.Height = operand1.Height + operand2.Height / 2;
board.Width = operand1.Width + operand2.Width;
board.alignHeight = operand1.alignHeight + operand2.Height / 2; // this step is important
break;
case Binary_node.Operator.LOG:
MathText logID = new MathText("log", fontsize);
operand1 = RenderElement((exp as Binary_node).node1, fontsize * logRatio);
MathText lparen = new MathText("(", fontsize);
operand2 = RenderElement((exp as Binary_node).node2, fontsize);
MathText rparen = new MathText(")", fontsize);
// first, we apply ArrangeHorizontal
board = ArrangeHorizontalGroup(logID, operand1, lparen, operand2, rparen);
// then, adjust operand1
board.Children.Remove(operand1);
Canvas.SetTop(operand1, Canvas.GetTop(board.Children[0]) + board.Children[0].DesiredSize.Height * 2 / 3);
board.Children.Add(operand1);
// update height of canvas `board`
board.Height = Math.Max(Canvas.GetTop(board.Children[0]) + board.Children[0].DesiredSize.Height * 2 / 3 + operand1.Height, board.Height);
break;
default:
break;
}
}
else if (exp is Unary_node)
{
MathText funcText = new MathText(funcID[(int)(exp as Unary_node).func] + "(", fontsize);
AlignCanvas inner_node = RenderElement((exp as Unary_node).node1, fontsize);
MathText rparen = new MathText(")", fontsize);
board = ArrangeHorizontalGroup(funcText, inner_node, rparen);
}
else if (exp == null)
{
Rectangle placeholder = new Rectangle();
placeholder.Width = fontsize;
placeholder.Height = fontsize;
placeholder.Fill = System.Windows.Media.Brushes.LightBlue;
board = new AlignCanvas();
board.Children.Add(placeholder);
board.Height = placeholder.Height;
board.Width = placeholder.Width;
board.alignHeight = board.Height / 2;
}
return(board);
}