util/geometry: support 'Rect::from_xml'

This patch eases the creation of 'Point', 'Area', and 'Rect' objects
from XML attribute values.

Fixes #4584
This commit is contained in:
Norman Feske 2022-08-17 12:37:13 +02:00
parent 5319f36788
commit 42edac8a34

View File

@ -15,6 +15,7 @@
#define _INCLUDE__UTIL__GEOMETRY_H_ #define _INCLUDE__UTIL__GEOMETRY_H_
#include <util/misc_math.h> #include <util/misc_math.h>
#include <util/xml_node.h>
#include <base/stdint.h> #include <base/stdint.h>
#include <base/output.h> #include <base/output.h>
@ -68,6 +69,17 @@ class Genode::Point
Genode::print(out, _x >= 0 ? "+" : "-", abs(_x), Genode::print(out, _x >= 0 ? "+" : "-", abs(_x),
_y >= 0 ? "+" : "-", abs(_y)); _y >= 0 ? "+" : "-", abs(_y));
} }
/**
* Construct point from XML node attributes
*
* The XML node is expected to feature the attributes 'xpos' and 'ypos'.
*/
static Point from_xml(Xml_node const &node)
{
return Point((CT)node.attribute_value("xpos", (CT)0),
(CT)node.attribute_value("ypos", (CT)0));
}
}; };
@ -104,6 +116,18 @@ class Genode::Area
bool operator == (Area const &a) const { return a.w() == _w && a.h() == _h; } bool operator == (Area const &a) const { return a.w() == _w && a.h() == _h; }
void print(Output &out) const { Genode::print(out, _w, "x", _h); } void print(Output &out) const { Genode::print(out, _w, "x", _h); }
/**
* Construct area from XML node attributes
*
* The XML node is expected to feature the attributes 'width' and
* 'height'.
*/
static Area from_xml(Xml_node const &node)
{
return Area((DT)node.attribute_value("width", (DT)0),
(DT)node.attribute_value("height", (DT)0));
}
}; };
@ -210,9 +234,21 @@ class Genode::Rect
* *
* The output has the form 'width' x 'height' +/- 'p1.x' +/- 'p1.y'. * The output has the form 'width' x 'height' +/- 'p1.x' +/- 'p1.y'.
* For example, a rectange of size 15x16 as position (-13, 14) is * For example, a rectange of size 15x16 as position (-13, 14) is
* printed as "15x16-13+14" * printed as "15x16-13+14".
*/ */
void print(Output &out) const { Genode::print(out, area(), p1()); } void print(Output &out) const { Genode::print(out, area(), p1()); }
/**
* Construct rectangle from XML node attributes
*
* The XML node is expected to feature the attributes 'xpos', 'ypos'.
* 'width', and 'height'. If an attribute is absent, the corresponding
* value is set to 0.
*/
static Rect from_xml(Xml_node const &node)
{
return Rect(Point<CT>::from_xml(node), Area<DT>::from_xml(node));
}
}; };
#endif /* _INCLUDE__UTIL__GEOMETRY_H_ */ #endif /* _INCLUDE__UTIL__GEOMETRY_H_ */