* Written by C�dric Moonen (email@example.com)
* This code may be used for any non-commercial and commercial purposes in a compiled form.
* The code may be redistributed as long as it remains unmodified and providing that the
* author name and this disclaimer remain intact. The sources can be modified WITH the author
* consent only.
* This code is provided without any garanties. I cannot be held responsible for the damage or
* the loss of time it causes. Use it at your own risks
* An e-mail to notify me that you are using this code is appreciated also.
//! A specialization of the CChartAxis class for displaying date and time data.
class CChartDateTimeAxis : public CChartAxis
//! Enum listing the different base intervals.
//! Sets the tick increment.
The tick increment is the value between two adjacents
ticks on the axis. In case of a date time axis, the interval
is specified by a time period because this interval might not
be constant (for instance, if a tick interval of one month is
specified, the distance between two adjacents ticks is not
constant: it depends on the number of days in the month).
The full tick interval is made of a base interval (day, month,
hour, ...) and a multiplier, that is applied to this base interval.
So, for an interval of three months between two ticks, you have to
specify tiMonth for the interval and 3 for the multiplier.
Specifies if the tick increment is automatically calculated.
The base interval.
The multiplier applied to the base interval.
void SetTickIncrement(bool bAuto, TimeInterval Interval, int Multiplier);
//! Sets the format of the tick labels.
Specifies if the format is calculated automatically.
The format to apply to the tick label if bAutomatic is false.
<br>Check the documentation of the COleDateTime::Format function on
MSDN for more information about the format string.
void SetTickLabelFormat(bool bAutomatic, const TChartString& strFormat);
//! Sets the reference tick.
The reference tick is a date/time which specifies a tick which should
always be displayed on the axis. This is needed when the tick
interval multiplier is not 1 (e.g. the interval between two ticks is 3
months). In that specific case, there is no way for the control to know
which ticks should be displayed (in our example, the chart doesn't know
if the first tick will be january, february or march). This is particularly
annoying when the axis is panned (in that case, if we always take the first
month on the axis as first tick, the ticks will always switch from one month
to another). By having a refence tick, this forces the control to calculate
all tick intervals based on this reference. It is set to January 1st 2000 by
void SetReferenceTick(COleDateTime referenceTick);
//! Default constructor
//! Default destructor
double GetFirstTickValue() const;
bool GetNextTickValue(double dCurrentTick, double& dNextTick) const;
TChartString GetTickLabel(double TickValue) const;
long ValueToScreenDiscrete(double Value) const;
long GetTickPos(double TickVal) const;
//! Forces a refresh of the date/time tick label format
//! Add a number of months to a date.
The function takes care of 'overflow' (total number
of months higher than 12) error when adding the months.
The date to which months will be added.
The number of months to add to the date.
@return the resulting date.
COleDateTime AddMonthToDate(const COleDateTime& Date,
int iMonthsToAdd) const;
double GetTickBeforeVal(double dValue) const;
//! Format of the date/time tick labels
//! Specifies if the tick labels format is automatic
//! Specifies the base time interval for ticks
This specifies an base interval in sec, min, hour,
day, month or year. The total tick increment is
a mutliple of this base interval (specified by
m_iDTTickIntervalMult). E.g: 2 days
//! Specifies the multiplicator for the base interval
This multiplies the base interval for the ticks, resulting
in something like 3 minutes (a multiplicator of 1 can also
//! Caches the value of the first tick.
//! The reference tick. See the SetReferenceTick function for details.
#endif // _CHARTDATETIMEAXIS_H_