```
class OEImageBase
```

The `OEImageBase` is an abstract class that
provides methods for drawing basic geometric shapes such as lines,
circles, rectangles etc.

- The following classes derive from this class:

```
OEImageBase(double width=200.0, double height=200.0)
```

Default constructor that creates an image with the specified width and height.

*width, height*- The dimensions of the image, both have to be positive (non-zero) numbers.

```
void Clear(const OESystem::OEColor &color=OESystem::OEWhite)
```

Clears the image with the given color.

See also

`OEColor`class

```
void DrawArc(const OE2DPoint ¢er, double bgnAngle, double endAngle,
double radius, const OEPen &pen)
```

Draws the outline of an arc.
See example in *Figure: Example of arc*.

*center*- The center of the arc.
*bgnAngle*,*endAngle*- The two endpoints of the arc (in degrees).
Both angles are in degrees and their values have to be in a
range of \([0.0^{\circ}, 360.0^{\circ}]\).
Angles are interpreted such that \(0.0^{\circ}\) and
\(360.0^{\circ}\) degrees are at the
*12 o’clock*position, \(90.0^{\circ}\) degrees corresponds to*3 o’clock*, etc. *radius*- The radius of the arc.
*pen*- The graphical properties of the curve (such as color,
line width, etc).
See examples in
*Figure: Example of drawing arcs with various pens*.

Note

`OEImageBase::DrawArc` supports all the
`OEPen` properties (i.e. color, line width, line
stipple) except the fill property.
See also `OEImageBase::DrawPie` method.

Arcs are always drawn in a clockwise direction. This means that
bgn = \(0.0^{\circ}\), end = \(90.0^{\circ}\) angle pair
is not the same as bgn = \(90.0^{\circ}\), end =
\(0.0^{\circ}\) angle pair.
See examples in *Table: Example of interpreting the begin and end angles of the arc*.

bgn = \(0.0^{\circ}\) end = \(90.0^{\circ}\) | bgn = \(90.0^{\circ}\) end = \(0.0^{\circ}\) |
---|---|

```
void DrawCircle(const OE2DPoint ¢er, double radius, const OEPen &pen)
```

Draws a circle.
See example in *Figure: Example of circle*.

*center*- The center of the circle.
*radius*- The radius of the circle.
*pen*- The graphical properties of the circle (such as color,
line width, etc).
See examples in
*Figure: Example of drawing circles with various pens*.

```
void DrawCubicBezier(const OE2DPoint &bgn, const OE2DPoint &c1,
const OE2DPoint &c2, const OE2DPoint &end, const OEPen &pen)
```

Draws a cubic Bézier curve.
See example in *Figure: Example of cubic Bezier curve*.

*bgn, end*- The end points of the Bezier curve.
*c1, c2*- The control points of the curve.
*pen*- The graphical properties of the Bézier curve (such as color,
line width, etc).
See examples in
*Figure: Example of drawing cubic Bezier curves with various pens*.

Example (*Figure: Example of drawing a cubic Bezier curve*)

```
OEImage image(100, 100);
OE2DPoint b(20, 70);
OE2DPoint e(60, 70);
OE2DPoint c1 = b + OE2DPoint(50, -60);
OE2DPoint c2 = e + OE2DPoint(50, -60);
OEPen pen(OELightGreen, OEBlack, OEFill::On, 2.0);
image.DrawCubicBezier(b, c1, c2, e, pen);
```

```
void DrawLine(const OE2DPoint &bgn, const OE2DPoint &end, const OEPen &pen)
```

Draws a line.
See example in *Figure: Example of line*.

*bgn*,*end*- The two endpoints of the line.
*pen*- The graphical properties of the line (such as color,
line width, etc).
See examples in
*Figure: Example of drawing lines with various pens*.

```
void DrawPath(const OE2DPath& path, const OEPen& pen);
```

Draws as path.
See example in *Figure: Example of path*.

*path*- The
`OE2DPath`object that defines a path as a sequence of lines and curves. *pen*- The graphical properties of the pie (such as color,
line width, etc).
See examples in
*Figure: Example of drawing paths with various pens*.

Example (*Figure: Example of drawing a path*)

```
OEImage image(100, 100);
OE2DPath path(OE2DPoint(20, 80));
path.AddLineSegment(OE2DPoint(80, 80));
path.AddLineSegment(OE2DPoint(80, 40));
path.AddCurveSegment(OE2DPoint(80, 10), OE2DPoint(20, 10), OE2DPoint(20, 40));
OEPen pen(OELightGreen, OEBlack, OEFill::On, 2.0);
image.DrawPath(path, pen);
```

```
void DrawPie(const OE2DPoint ¢er, double bgnAngle, double endAngle,
double radius, const OEPen &pen)
```

Draws a pie.
See example in *Figure: Example of drawing a pie*.

*center*- The center of the pie.
*bgnAngle*,*endAngle*- The two endpoints of the pie (in degrees).
Both angles are in degrees and their values have to be in a
range of \([0.0^{\circ}, 360.0^{\circ}]\).
Angles are interpreted such that \(0.0^{\circ}\) and
\(360.0^{\circ}\) degrees are at the
*12 o’clock*position, \(90.0^{\circ}\) degrees corresponds to*3 o’clock*, etc. *radius*- The radius of the pie.
*pen*- The graphical properties of the pie (such as color,
line width, etc).
See examples in
*Figure: Example of drawing pies with various pens*.

Pies are always drawn in a clockwise direction. This means that
bgn = \(0.0^{\circ}\), end = \(90.0^{\circ}\) angle pair
is not the same as bgn = \(90.0^{\circ}\), end =
\(0.0^{\circ}\) angle pair.
See examples in *Table: Example of interpreting the begin and end angles of the pie*.

bgn = \(0.0^{\circ}\) end = \(90.0^{\circ}\) | bgn = \(90.0^{\circ}\) end = \(0.0^{\circ}\) |
---|---|

```
void DrawPoint(const OE2DPoint &p, const OESystem::OEColor &color) = 0
```

Draws a point.
See example in *Figure: Example of point*.

*p*- The position of the point, where p = OE2DPoint(x, y).
*color*- The color of the point.

See also

`OEColor`class

```
void DrawPolygon(const std::vector<OE2DPoint> &points, const OEPen &pen)
```

Draws a closed polygon.
See example in *Figure: Example of polygon*.

*points*- The series of points that defines the polygon.
The polygon will be closed
*i.e.*the first connected with the last point. *pen*- The graphical properties of the polygon (such as color,
line width, etc).
See examples in
*Figure: Example of polygons lines with various pens*.

Example (*Figure: Example of drawing a polygon*)

```
OEImage image(100, 100);
std::vector<OE2DPoint> polygon;
polygon.push_back(OE2DPoint(20, 20));
polygon.push_back(OE2DPoint(40, 40));
polygon.push_back(OE2DPoint(60, 20));
polygon.push_back(OE2DPoint(80, 40));
polygon.push_back(OE2DPoint(80, 80));
polygon.push_back(OE2DPoint(20, 80));
OEPen pen(OELightGreen, OEBlack, OEFill::On, 2.0);
image.DrawPolygon(polygon, pen);
```

```
void DrawQuadraticBezier(const OE2DPoint &bgn, const OE2DPoint &c,
const OE2DPoint &end, const OEPen &pen)
```

Draws a quadratic Bézier curve.
See example in *Figure: Example of quadratic Bezier curve*.

*bgn, end*- The end points of the Bézier curve.
*c*- The control point of the curve.
*pen*- The graphical properties of the Bézier curve (such as color,
line width, etc).
See examples in
*Figure: Example of drawing quadratic Bezier curves with various pens*.

Example (*Figure: Example of drawing a polygon*)

```
OEImage image(100, 100);
OE2DPoint b(20, 70);
OE2DPoint e(80, 70);
OE2DPoint c = b + OE2DPoint(30, -80);
OEPen pen(OELightGreen, OEBlack, OEFill::On, 2.0);
image.DrawQuadraticBezier(b, c, e, pen);
```

```
void DrawRectangle(const OE2DPoint &tl, const OE2DPoint &br, const OEPen &pen)
```

Draws a rectangle.
See example in *Figure: Example of rectangle*.

*tl*- The top left corner of the rectangle.
*br*- The bottom right corner of the rectangle.
*pen*- The graphical properties of the rectangle (such as color,
line width, etc).
See examples in
*Figure: Example of polygons rectangles with various pens*.

```
void DrawText(const OE2DPoint ¢er, const std::string &text, const OEFont &font,
double maxwidth=0.0)
```

Draws a text.
See example in *Figure: Example of text*.

*center*- The position of the text.
*text*- The characters to be displayed.
*font*- The graphical properties of the displayed text (such as color,
font size, etc).
See examples in
*Figure: Example of drawing texts with various fonts*. *maxwidth*- If
*maxwidth*is specified and the width of the text would exceed the given limit, than the size of the font used to display the text is automatically reduced.

Note

The displayed position of the text not only depends on ‘c’
position but also the alignment style of the given
`OEFont`.

See also

`OE2DPoint`class`OEAlignment`namespace`OEFont`class

```
void DrawTriangle(const OE2DPoint &a, const OE2DPoint &b, const OE2DPoint &c,
const OEPen &pen)
```

Draws a triangle.
See example in *Figure: Example of triangle*.

*a*,*b*,*c*- The three corners of the triangle.
*pen*- The graphical properties of the triangle (such as color,
line width, etc).
See examples in
*Figure: Example of polygons triangles with various pens*.

```
const OE2DPoint& GetGlobalOffset() const
```

Returns the offset from the origin (x=0.0, y=0.0) to the top-left corner of the given image.

```
unsigned int GetMinFontSize() const
```

Returns the minimum size of the font that can be displayed.

```
void SetMinFontSize(unsigned int fontsize)
```

Sets the minimum size of the font that can be displayed.