Rubband - rubberbanding graphical objects
#include <InterViews/rubband.h>
#include <InterViews/rubcurve.h>
#include <InterViews/rubgroup.h>
#include <InterViews/rubline.h>
#include <InterViews/rubrect.h>
#include <InterViews/rubverts.h>
Rubband is the base class for a set of classes that provide
graphical feedback to a user during an interactive operation such as sizing
a rectangle. A rubberband varies in appearance as its tracking point
changes. A rubberband is not an interactor itself; interactors use
rubberbands to provide animated effects. Because rubberbands are not
interactors, rubberband constructors must be passed the painter and canvas
to use for drawing.
- RubberLine(
- Painter*,
Canvas*, Coord fx, fy, mx, my, offx = 0, offy = 0
- )
-
A rubber line stretches to follow the tracking point while its other
endpoint stays tied down.
- RubberAxis(
- Painter*,
Canvas*, Coord fx, fy, mx, my, offx = 0, offy = 0
- )
-
A rubber axis stretches either horizontally or vertically to follow the
tracking point while its other endpoint stays tied down. One endpoint
stays fixed while the other moves along either the horizontal or vertical
axis, whichever is closer to the tracking point.
- SlidingLine(
- Painter*,
Canvas*, Coord x0, y0, x1, y1, rfx, rfy,
- Coord offx = 0, offy =
0
- )
-
A sliding line slides around without changing its length or angle as the
tracking point moves around a reference point.
- RotatingLine(
- Painter*,
Canvas*, Coord x0, y0, x1, y1, rfx, rfy,
- Coord offx = 0, offy
= 0
- )
-
A rotating line rotates around (cx, cy) based on the
angle between the radius from (cx, cy) to
(rfx, rfy) and the radius from
(cx, cy) to the tracking point.
- RubberRect(
- Painter*,
Canvas*, Coord fx, fy, mx, my, offx = 0, offy = 0
- )
-
A rubber rectangle stretches to follow the tacking point while its opposite
corner stays tied down.
- SlidingRect(
- Painter*,
Canvas*, Coord x1, y1, x2, y2, rfx, rfy,
- Coord offx = 0, offy
= 0
- )
-
A sliding rectangle slides around the screen without changing its side or
orientation as the tracking point moves around a reference point.
- ScalingRect(
- Painter*,
Canvas*, Coord x1, y1, x2, y2, cx, cy,
- Coord offx = 0, offy
= 0
- )
-
A scaling rectangle scales equally in both dimensions about
(cx, cy) to keep one edge intersecting the tracking
point.
- RotatingRect(
- Painter*,
Canvas*, Coord x1, y1, x2, y2, cx, cy, rfx, rfy,
- Coord offx = 0, offy
= 0
- )
-
A rotating rectangle rotates about (cx, cy) based on
the radius from (cx, cy) to
(rfx, rfy) and the radius from
(cx, cy) to the tracking point.
- StretchingRect(
- Painter*,
Canvas*, Coord x1, y1, x2, y2, Side ts,
- Coord offx = 0, offy
= 0
- )
-
A stretching rectangle's tracking side follows the tracking point while the
opposite side stays fixed. The side can be one of LeftSide,
RightSide, BottomSide, or TopSide.
- RubberCircle(
- Painter*,
Canvas*, Coord cx, cy, rx, ry, offx = 0, offy = 0
- )
-
A rubber circle's radius varies with the magnitude of the tracking point's
distance from (cx, cy).
- RubberEllipse(
- Painter*,
Canvas*, Coord cx, cy, rx, ry, offx = 0, offy = 0
- )
-
A rubber ellipse's horizontal and vertical radii vary with the magnitude of
the tracking point's distance from (cx, cy).
- RubberSpline(
- Painter*,
Canvas*, Coord x[], y[], int n, pt,
- Coord offx = 0, offy
= 0
- )
-
- RubberClosedSpline(
- Painter*,
Canvas*, Coord x[], y[], int n, pt,
- Coord offx = 0, offy
= 0
- )
-
A rubber spline is the section of a B-spline defined by n control
points that changes shape as the control point indexed by pt is set
to the tracking point.
- RubberHandles(
- Painter*,
Canvas*, Coord x[], y[], int n, pt, size,
- Coord offx = 0, offy
= 0
- )
-
A rubber handles object is a set of filled squares centered about each point
in the list. The point index by pt follows the tracking point.
- SlidingPointList(
- Painter*,
Canvas*, Coord x[], y[], int n, pt, Coord rfx, rfy,
- Coord offx = 0,
offy = 0
- )
-
A sliding point list slides around the screen without changing its
appearance as the tracking point moves around a reference point.
- SlidingLineList(
- Painter*,
Canvas*, Coord x[], y[], int n, pt, Coord rfx, rfy,
- Coord offx = 0,
offy = 0
- )
-
A sliding line list slides around the screen without changing the appearance
of its connected lines as the tracking point moves around
(rfx, rfy).
- ScalingLineList(
- Painer*, Canvas*,
Coord x[], Coord y[], int n,
- Coord cx, cy, rfx,
rfy, offx = 0, offy = 0
- )
-
A scaling line list scales a list of lines about (cx, cy) to keep the
line list's bounding box intersecting the tracking point.
- RotatingLineList(
- Painer*,
Canvas*, Coord x[], Coord y[], int n,
- Coord cx, cy, rfx,
rfy, offx = 0, offy = 0
- )
-
A rotating line list rotates a list of lines about (cx, cy) based on
the angle between the radius from (cx, cy) to
(rfx, rfy) and the radius from
(cx, cy) to the tracking point.
- GrowingVertices(
- Painter*,
Canvas*, Coord x[], y[], int n,
- int pt = -1, int handleSize
= -1
- )
-
- GrowingMultiLine(
- Painter*,
Canvas*, Coord x[], y[], int n,
- int pt = -1, int
handleSize = -1
- )
-
- GrowingPolygon(
- Painter*,
Canvas*, Coord x[], y[], int n,
- int pt = -1, int
handleSize = -1
- )
-
- GrowingBSpline(
- Painter*,
Canvas*, Coord x[], y[], int n,
- int pt = -1, int
handleSize = -1
- )
-
- GrowingClosedBSpline(
- Painter*,
Canvas*, Coord x[], y[], int n,
- int pt = -1, int
handleSize = -1
- )
-
- virtual void
AddVertex(Coord, Coord)
- virtual void
RemoveVertex()
- GrowingVertices is an abstract rubberband containing a list of vertices
that grows or shrinks dynamically. The pt parameter specifies the
index of the vertex that will follow the tracking point; a value of -1
specifies a vertex after the last one in the list. The handleSize
parameter specifies the size of the handle drawn at each vertex (as in
RubberHandles above); a value of -1 specifies that no handles be drawn.
The AddVertex operation adds a new vertex at the tracking
point to the list and makes the next (or last) vertex in the list follow
the tracking point. RemoveVertex removes the vertex at the tracking
point and makes the previous (or first) vertex the new tracking point.
GrowingMultiLine, GrowingPolygon, GrowingBSpline, and
GrowingClosedBSpline are GrowingVertices subclasses that draw a
multiline, polygon, B-spline, and closed B-spline, respectively.
- RubberGroup(Painter*,
Canvas*)
- void Append(
-
Rubberband*, Rubberband* = nil, Rubberband* = nil,
- Rubberband*
= nil
- )
-
- void
Remove(Rubberband*)
- void
RemoveCur()
- void
SetCurrent(Rubberband*)
- Rubberband*
GetCurrent()
- Rubberband*
First()
- Rubberband*
Last()
- Rubberband*
Next()
- Rubberband*
Prev()
- boolean
IsEmpty()
- boolean
AtEnd()
- A RubberGroup composes other rubberbands, providing operations for
including, excluding, and traversing its children. RubberGroups are useful
for combining the behavior of several rubberbands into one, eliminating
the need to call Track on multiple rubberbands. The RubberGroup's
SetCanvas and SetPainter operations set the children's canvas and painter
as well as the RubberGroup's, but the children do not otherwise inherit
the group's canvas and painter. The Track operation calls Track on each
child with the same parameters.
- virtual void
Draw()
- void
Redraw()
- virtual void
Erase()
- Explicitly draw, redraw, and erase the rubberband. Multiple calls to Draw
without an intervening Erase will only draw the rubberband once. Redraw
forces the rubberband to be drawn. Since rubberbands are drawn in XOR
mode, Redraw will erase the rubberband every other time it is called.
These functions are used only on occasion, for example, when part of the
screen is erased while a rubberband is visible. The Track function is
normally used to draw the rubberband in response to mouse input.
- virtual void
Track(Coord x, Coord y)
- Erase the rubberband and redraw it using the new tracking point.
- void
GetOriginal(Coord& x1, Coord& y2, Coord& x2, Coord&
y2)
- void
GetCurrent(Coord& x1, Coord& y2, Coord& x2, Coord&
y2)
- GetOriginal obtains the original points specified for the rubberband.
GetCurrent obtains the current points based on the most recent call to
Track. The meaning of the points depends on the kind of rubberband. For
lines, the points are the endpoints; for rectangles, the points are
opposite corners; for curves, (x1, y1) is the center
and x2 and y2 are the radii.
- virtual void
SetPainter(Painter*)
- Painter*
GetPainter()
- Explicitly set and get the painter used by the rubberband. By default,
rubberbands use a copy of the painter passed to their constructor. The
user can specify a particular painter to use by passing a nil painter to
the constructor and later calling SetPainter. N.B.: the rubberband
may alter the painter specified via SetPainter.
- virtual void
SetCanvas(Canvas*)
- Canvas*
GetCanvas()
- Explicitly set and get the canvas used by the rubberband.