SVGHMI: add support for "reference" and "frame" rectangles to spread-out ovelapping elements.
When HMI become complicated, designer needs to spread-out ovelapping elements
in order to unclutter drawing and facilitate maintenance.
<?xml version='1.0' encoding='utf-8'?>
<PyFile xmlns:xhtml="http://www.w3.org/1999/xhtml" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<variables>
<variable name="SomePLCglobal" type="HMI_STRING" initial="'blaf'" onchange="MyOnChangeFunc"/>
</variables>
<globals>
<xhtml:p><![CDATA[
def MyOnChangeFunc(changed_var_name):
print changed_var_name + ": " + getattr(PLCGlobals, changed_var_name)
]]></xhtml:p>
</globals>
<init>
<xhtml:p><![CDATA[
]]></xhtml:p>
</init>
<cleanup>
<xhtml:p><![CDATA[
]]></xhtml:p>
</cleanup>
<start>
<xhtml:p><![CDATA[
]]></xhtml:p>
</start>
<stop>
<xhtml:p><![CDATA[
]]></xhtml:p>
</stop>
</PyFile>