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:

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

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

• OEImageBase::DrawArc method

• OE2DPoint class

• OEPen class

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.

Example of drawing a circle

See also

• OEImageBase::DrawCircle method

• OE2DPoint class

• OEPen class

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.

Example of drawing a cubic Bezier curve

See also

• OEImageBase::DrawCubicBezier method

• OE2DPoint class

• OEPen classes

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

• OEImageBase::DrawLine method

• OE2DPoint class

• OEPen class

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

• OEImageBase::DrawPath method

• OE2DPath class

• OEPen class

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

• OEImageBase::DrawPie method

• OE2DPoint class

• OEPen class

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

• OEImageBase::DrawPoint method

• OE2DPoint class

• OEColor class

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.

Example of drawing a polygon

See also

• OEImageBase::DrawPolygon method

• OE2DPoint class

• OEPen class

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.

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.

Example of drawing a rectangle

See also

• OEImageBase::DrawRectangle method

• OE2DPoint class

• OEPen class

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

• OEImageBase::DrawText method

• OE2DPoint class

• OEFont class

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.

Example of drawing a triangle

See also

• OEImageBase::DrawTriangle method

• OE2DPoint class

• OEPen class

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.