OEImage¶

class OEImage : public OEImageBase

OEImage class is implemented as a display list i.e. a container of drawing commands. For example, when the OEImage::DrawLine method is called, rather than immediately drawing a line specified by the parameters, a line drawing operation is created that copies all parameters for later execution.

When the OEImage::Render method is invoked, the drawing commands stored in the OEImage object are executed in the same order in which they were issued.

The following methods are publicly inherited from OEImageBase:

Constructors¶

OEImage(double width, double height, const OESystem::OEColor& bgColor = OESystem::OEWhite);

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

width, height: The dimensions of the image, both have to be positive (non-zero) numbers.
bgColor: The color that is used to clear the image upon construction. The default background color is OEWhite. A .png image with transparent background can be generated by passing the OETransparentColor as the background color.

OEImage(const OEImage &rhs)

Copy constructor.

OEImage(const OEImage &src, double scale)

Copy constructor with scaling.

scale: The scaling factor is used to create a new image from the given one. The scaling factor has to be a positive (non-zero) number.

The following code snippet shows how to half and double the size of an image.

OEImage image(100.0, 100.0);

image.DrawCircle(OEGetCenter(image), 40.0, OEBlackPen);
image.DrawText(OEGetCenter(image), "circle", OEDefaultFont);
OEDrawBorder(image, OELightGreyPen);

OEWriteImage("image.png", image);

OEImage halfimage(image, 0.5);
OEWriteImage("halfimage.png", halfimage);

OEImage doubleimage(image, 2.0);
OEWriteImage("doubleimage.png", doubleimage);

**Examples of image scaling**
original image	scale = 0.5	scale = 2.0

Clear¶

void Clear(const OESystem::OEColor &color)

Appends a clear command to the display list of the OEImage object.

See also

OEImageBase::Clear method
OEColor class

DrawArc¶

void DrawArc(const OE2DPoint &center, double bgnAngle, double endAngle,
             double radius, const OEPen &pen)

Appends an arc drawing command to the display list of the OEImage object. See example in Figure: Example of drawing an arc.

Example of drawing an arc

See also

DrawCircle¶

void DrawCircle(const OE2DPoint &center, double radius, const OEPen &pen)

Appends a circle drawing command to the display list of the OEImage object. See example in Figure: Example of drawing a circle.

../../_images/OEImageBase-DrawCircle.png

Example of drawing a circle

See also

DrawCubicBezier¶

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

Appends a cubic Bézier curve drawing command to the display list of the OEImage object. See example in Figure: Example of drawing a cubic Bezier curve.

../../_images/OEImageBase-DrawCubicBezier.png

Example of drawing a cubic Bezier curve

See also

DrawLine¶

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

Appends a line drawing command to the display list of the OEImage object. See example in Figure: Example of drawing a line.

Example of drawing a line

See also

DrawPath¶

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

Appends a path drawing command to the display list of the OEImage object. See example in Figure: Example of drawing a path.

Example of drawing a path

See also

DrawPie¶

void DrawPie(const OE2DPoint &center, double bgnAngle, double endAngle,
             double radius, const OEPen &pen)

Appends a pie drawing command to the display list of the OEImage object. See example in Figure: Example of drawing a pie.

Example of drawing a pie

See also

DrawPoint¶

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

Appends a point drawing command to the display list of the OEImage object. See example in Figure: Example of drawing a point.

Example of drawing a point

See also

DrawPolygon¶

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

Appends a polygon drawing command to the display list of the OEImage object. See example in Figure: Example of drawing a polygon.

../../_images/OEImageBase-DrawPolygon.png

Example of drawing a polygon

See also

DrawQuadraticBezier¶

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

Appends a quadratic Bézier curve drawing command to the display list of the OEImage object. See example in Figure: Example of drawing a quadratic Bezier curve.

../../_images/OEImageBase-DrawQuadraticBezier.png

Example of drawing a quadratic Bezier curve

See also

OEImageBase::DrawQuadraticBezier method
OE2DPoint class
OEPen classes

DrawRectangle¶

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

Appends a polygon drawing command to the display list of the OEImage object. See example in Figure: Example of drawing a rectangle.

../../_images/OEImageBase-DrawRectangle.png

Example of drawing a rectangle

See also

DrawText¶

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

Appends a text drawing command to the display list of the OEImage object. See example in Figure: Example of drawing a text.

Example of drawing a text

See also

DrawTriangle¶

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

Appends a triangle drawing command to the display list of the OEImage object. See example in Figure: Example of drawing a triangle.

../../_images/OEImageBase-DrawTriangle.png

Example of drawing a triangle

See also

GetHeight¶

double GetHeight() const

Returns the height of the OEImage object.

GetWidth¶

double GetWidth() const

Returns the width of the OEImage object.

IsEmpty¶

bool IsEmpty() const

Returns whether or not the display list of the OEImage object is empty.

Render¶

bool Render(OEImageBase &image) const

Renders the image stored in the OEImage object by executing the stored drawing commands in the order in which they were issued.

`Clear`	`DrawPie`	`DrawTriangle`
`DrawArc`	`DrawPoint`	`GetGlobalOffset`
`DrawCircle`	`DrawPolygon`	`GetHeight`
`DrawCubicBezier`	`DrawQuadraticBezier`	`GetMinFontSize`
`DrawLine`	`DrawRectangle`	`GetWidth`
`DrawPath`	`DrawText`	`GetSVGClass`
`GetSVGGroup`	`NewSVGClass`	`NewSVGGroup`
`PopGroup`	`PushGroup`	`SetMinFontSize`