Attribute Variables in Code

The following example shows how an attribute variable that returns a double can be created or modified through code.

// Set the width of a LineVisualizer that visualizes roads to a constant value.
roadVisualizer.Width = 5.0;
	
// Set the width of a LineVisualizer to the value of the attribute ROAD_CLASS,
// if the attribute is missing we set the width to 5.
roadVisualizer.Width = new IndirectAttributeVariable<double>("ROAD_CLASS", 5.0);
	
// Same as the indirect example above but use an ExpressionAttributeVariable.
// Note that we use the shorthand version of an if-then-else expression.
roadVisualizer.Width = new ExpressionAttributeVariable<double>(
	"ROAD_CLASS, 5.0");
	
// Use a KeyedAttributeVariable and the value of the ROAD_CLASS attribute to
// look up the value in a table so that:
//
// ROAD_CLASS 1 => 1
// ROAD_CLASS 2 => 5
// ROAD_CLASS 3 => 10
// 
// If the ROAD_CLASS attribute is missing we set the width to 5.
KeyedAttributeVariable<double> roadWidth = 
	new KeyedAttributeVariable<double>("ROAD_CLASS");
roadWidth.DefaultValue = 5.0;
roadWidth.Table[1] = 1.0;
roadWidth.Table[2] = 5.0;
roadWidth.Table[3] = 10.0;
roadVisualizer.Width = roadWidth;

The following example shows how an attribute variable that returns a double can be created or modified through code.

C++

// Set the width of a LineVisualizer that visualizes roads to a constant value.
roadVisualizer->width(new DirectDoubleAttributeVariable(5.0));
	
// Set the width of a LineVisualizer to the value of the attribute ROAD_CLASS,
// if the attribute is missing we set the width to 5.
roadVisualizer->width(new IndirectDoubleAttributeVariable("ROAD_CLASS", 5.0));
	
// Same as the indirect example above but use an ExpressionAttributeVariable.
// Note that we use the shorthand version of an if-then-else expression.
roadVisualizer->width(new ExpressionDoubleAttributeVariable(
	"ROAD_CLASS, 5.0"));
	
// Use a KeyedAttributeVariable and the value of the ROAD_CLASS attribute to
// look up the value in a table so that:
//
// ROAD_CLASS 1 => 1
// ROAD_CLASS 2 => 5
// ROAD_CLASS 3 => 10
// 
// If the ROAD_CLASS attribute is missing we set the width to 5.
KeyedDoubleAttributeVariablePtr roadWidth = 
	new KeyedDoubleAttributeVariable("ROAD_CLASS");
roadWidth->defaultValue(5.0);
roadWidth->table()->add(1, 1.0);
roadWidth->table()->add(2, 5.0);
roadWidth->table()->add(3, 10.0);
roadVisualizer->width(roadWidth);

Attribute Variables in Code

The following example shows how an attribute variable that returns a double can be created or modified through code.

Java

// Set the width of a LineVisualizer that visualizes roads to a constant value.
roadVisualizer.setWidth(new DirectDoubleAttributeVariable(5.0));
	
// Set the width of a LineVisualizer to the value of the attribute ROAD_CLASS, if 
// the attribute is missing we set the width to 5.
roadVisualizer.setWidth(new IndirectDoubleAttributeVariable(new Atom("ROAD_CLASS"), 5.0);
	
// Same as the indirect example above but use an ExpressionAttributeVariable.
// Note that we use the shorthand version of an if-then-else expression.
roadVisualizer.setWidth(new ExpressionDoubleAttributeVariable(
	"ROAD_CLASS, 5.0"));
	
// Use a KeyedAttributeVariable and the value of the ROAD_CLASS attribute to
// look up the value in a table so that:
//
// ROAD_CLASS 1 => 1
// ROAD_CLASS 2 => 5
// ROAD_CLASS 3 => 10
// 
// If the ROAD_CLASS attribute is missing we set the width to 5.
KeyedDoubleAttributeVariable roadWidth = 
	new KeyedDoubleAttributeVariable(new Atom("ROAD_CLASS"));
roadWidth.setDefaultValue(5.0);
roadWidth.getTable().put(1, 1.0);
roadWidth.getTable().put(2, 5.0);
roadWidth.getTable().put(3, 10.0);
roadVisualizer.setWidth(roadWidth);

Attribute Variables in Code

The following example shows how an attribute variable that returns a double can be created or modified through code.

Python

# Set the width of a LineVisualizer that visualizes roads to a constant value.
roadVisualizer.Width = DirectRealAttributeVariable(5)
	
# Set the width of a LineVisualizer to the value of the attribute ROAD_CLASS,
# if the attribute is missing we set the width to 5.
roadVisualizer.Width = IndirectRealAttributeVariable("ROAD_CLASS", 5)
	
# Same as the indirect example above but use an ExpressionAttributeVariable.
# Note that we use the shorthand version of an if-then-else expression.
roadVisualizer.Width = ExpressionDoubleAttributeVariable("ROAD_CLASS, 5.0")
	
# Use a KeyedAttributeVariable and the value of the ROAD_CLASS attribute to
# look up the value in a table so that:
#
# ROAD_CLASS 1 => 1
# ROAD_CLASS 2 => 5
# ROAD_CLASS 3 => 10
# 
# If the ROAD_CLASS attribute is missing we set the width to 5.
roadWidth = KeyedRealAttributeVariable("ROAD_CLASS")
roadWidth.defaultValue = 5.0
roadWidth.table[1] = 1.0
roadWidth.table[2] = 5.0
roadWidth.table[3] = 10.0
roadVisualizer.width = roadWidth

Attribute Variables in Code

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Attribute Variables in Code

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Attribute Variables in Code

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Attribute Variables in Code

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