On Tue, 4 Jan 2005, bulia byak wrote:
On Tue, 4 Jan 2005 13:26:56 -0800 (PST), Bryce Harrington <bryce@...260...> wrote:
Actually, it does use the 0.80 factor, but in its inverted fashion (1.25). However I chose to make px the primary unit so the conversion factors are expressed as functions of px's rather than pt's.
This sounds good. I just did mostly the same, now there's only one 0.8 defined in one place.
Actually what I need from SPUnit is this:
sp_pixels_from_units, sp_units_from_pixels
SP_PX_TO_METRIC_STRING (currently it's in SPMetrics, but this class is redundant, it should be merged with SPUnit)
Okay, I'll make sure equivalents for those are there. This is good to know, because there's a lot of routines in there that I wonder whether they may not be needed.
Do you want to have wrapper functions by those exact names to hook to those, or do you just want a routine that provides the equivalent functionality? (I've dropped the sp prefix for this code and have been implementing routines as class members, but wrappers could probably be created if needed.)
functions to get ratios to and from px for all units (to replace the defines from unit-constants.h)
All of the linear document units are based on px as the primary unit so trivially these can be obtained via `u.factor` in the Unit structure.
For the unit widget I also added a convenience function for getting the conversion factor from whatever the user's selected to a different unit:
double getConversion(Glib::ustring const &new_unit_abbr) const;
Basically this just returns old_unit.factor / new_unit.factor but also does some checking that new_unit_abbr exists, and checks that neither factor is ~ zero. Possibly we could promote this convenience function up higher if other areas of the codebase also need to do similar conversions.
sp_get/set_value_in_pixels for an adjustment with a unit menu
Derek and I have crafted a new compound widget called ScalarUnit, which incorporates this functionality a bit more conveniently, and handles the Adjustments internally. To set the value/units for this unit, this function is provided:
void setValue(double number, Glib::ustring const &units);
(I am assuming the performance cost of specifying units as a string will be negligible; I think that's a pretty safe assumption, but if not, we can gain back most of the performance by using Quarks.)
In addition, if you wish to flip the units, this function can be used:
bool setUnit(Glib::ustring const &units);
This will also recalculate the value so it "means" the same thing in the new units.
There will also be signal handlers for unit system changes. That is, if the user changes preferences regarding their units (such as switching the default unit for the document), a signal can be issued and all unit widgets will update accordingly.
If you provide this in your implementation of SPUnit, it will be almost a drop-in replacement. Just please don't touch any unit stuff outside of SPUnit and SPMetrics and SPUnitMenu, because there were tons of changes and fixes recently, throughout the codebase, caused by the removal of 0.8 and the change in base zoom. Please just provide the above API and it should be easy to merge.
Alright, will do. Like I mentioned earlier, the only place this is hooked into right now is the Transformation dialog. We'll take care to not hook it in anywhere else for the time being.
Bryce