Distance between Staves:
a.) Two Main Algorithms for Staff Spacing in the Score
b.) Max. Distance between Staves (Default: 470 EVPU)
c.) Standard Distance Between Two-Staff Groups (Default: 280 EVPU)
d.) Sliders: Extra Distance Before/After Staff Groups and Staff/System Distance

Distance between Staff Systems:
e.) Max. Distance Between Staff Systems (Default: deactivated, 800 EVPU)
f.) Minimum Bottom Margin of Staff System and Auto-Suggest 'Parts' Value
g.) Reserve Distance Between Bottom and Next Top Staff System Margin (Default: 70 EVPU)
h.) Min. Vertical Space on Reflow Systems Across Pages (Default: 14 EVPU)

a.) Two Main Algorithms for Staff Spacing in the Score

The Perfect Layout plug-in includes two algorithms for creating a non-colliding and visually balanced look of the staff systems.

While the default algorithm is very flexible and also adds group spacing, the staff distances may vary a lot if there is not much vertical space and the content is different on each page.
The second algorithm tries to preserve the original layout as much as possible which leads to more a consistent spacing. But you have to make sure that the staff and group spacing already looks fine on most pages before applying Perfect Layout.

In Perfect Layout v3 the algorithms are applied both to the score and to the linked parts.
PL v2 supports the score layout only (not linked parts).

(1) The default staff spacing algorithm works fine on overstuffed pages as well as on pages with lots of free space.

Image 1a: Default staff spacing on an overstuffed page

The plug-in starts by creating the maximum condensed score and then inserts space for a good visual balance.
If there is way too much space, it won't stretch the page until the bottom page margin, but keep a portion free at the bottom of the page.

In general you should always get good results with the default score balancing settings of the plug-in.
Should you be unhappy with the result or would like to have access to more spacing parameters which are currently hidden to the user, please contact our support team.

(2) The second staff spacing algorithm (Option: "Systems->Optimize System Distances Only and Keep Staff Distances") tries to preserve the original staff layout, by only adjusting those staff distances where the staves are actually colliding vertically.
Activate this option only if your staves already have very good staff and group distances before applying Perfect Layout and if there are only few vertical collisions between the staves.

Image 1b: Comparison of both algorithms: "Optimize System Distances Only and Keep Staff Distances" activated and deactivated

Video: Automatic System Optimization by Only Adjusting the Colliding Staves and Preserving Most of the Layout

b.) Max. Distance between Staves (Default: 470 EVPU)

This value handles the maximum distance between staves.
If a staff group starts, then this value will be increased according to the "group slider".
Usually you will not get this distance between two staves as probably your page will not have that much space. But in case of very much space it will (probably) be limited to 470 EVPUs.
Probably? Why probably?
If only "a bit more" is required to fill the full page, more space will be used.
Some mathematical rounding issues can also lead to slightly different max. values.

c.) Standard Distance Between Two-Staff Groups (Default: 280 EVPU)

If there is a piano part on the staff system, it should not have a distance of 470 EVPU like the other single staves.
Instead, they should be aligned a bit tighter. 280 EVPU has been found to be a good value for typical piano or harp staves.

However, there may be complex piano notation that takes up varying amounts of space.
In such cases, it may be more consistent to allocate more space to piano staves than the default 280 EVPU, especially when they are next to other piano staves that require, for example, 380 EVPU.
The option "Adaptive Standard Distance for Scores with Very Small and Very Wide Staff Distances" will achieve this automatically.
However, in rare scenarios, it may be desirable to have a fixed distance between piano staves, even if they are close to other piano staves with a wide distance. In that case, this suboption should be deactivated.

d.) Sliders: Extra Distance Before/After Staff Groups and Staff/System Distance

Who gets the most empty space?

Multiple systems on a page or staves can get extra space: "between systems" or "between staves".
This can be controlled via the "Staff/System Distance" slider.
The more you move the slider to the right the more space is inserted between staff systems.

Extra space for grouped staves within a system is controlled via the "Extra Distance Before/After Staff Groups" slider.
The more you move the slider to the right the more extra space is inserted before and after groups.
By default these sliders are set to auto-detection: an algorithm automatically sets good default spacing values for standard score types like single staff, piano, piano + solo, duo, piano + duo, small ensemble or large ensemble.

e.) Max. Distance Between Staff Systems (Default: deactivated, 800 EVPU)

(Perfect Layout v3+ only:)
By default Perfect Layout automatically adds space between the staff systems, so that the bottom staff systems aligns with the page bottom margin.
If this meant very much free space between multiple systems, Perfect Layout would reduce the space and automatically avoid the alignment.

However, there are scores, for example with many very different staff system heights, where it makes sense to limit the maximum space between staff systems.
This also means that they won't align at the page bottom margin, if the maximum distance is reached.

To achieve this activate the option Max. Distance Between Staff Systems.
By default the distance is limited to 800 EVPU. But this value can also be adjusted in the dialog.
See image 2 for the difference between automatic staff system distances and a limited distance.

Image 2: Option "Max. Distance Between Staff Systems""

f.) Min. Bottom Margin of Staff System and Auto-Suggest 'Parts' Value

The "Minimum Bottom Margin of Staff System" value is available both for the score and the parts and has the highest influence on the distance between multiple systems on a page.

Especially in parts this is probably the most important value for the system layout.
For a very dense spacing use low values (e.g. 20 EVPU is the default in the 'Tight Spacing' preset).
For a wide spacing use higher value between 150-240 EVPU.

Note: The "Min. Bottom Margin" value will only provide a rough orientation for the plug-in.
The actual bottom margin of the systems will probably be different on each system dependent on the content.

In PL v3 there is also an "Auto-Suggest 'Parts' Value" option.
It tries to suggest a good value according to the spacing in the current system setup in the parts (before Perfect Layout).

"Auto-Suggest" will either generate a value of 80 EVPU (medium dense spacing) or 200 EVPU ("standard" spacing).

How does "Auto-Suggest" work?

Orchestral or chamber music parts very often use a more dense spacing. Other musical genres often use a wider spacing.
It's obviously difficult to detect if the engraver wanted a dense or wide system spacing.

The "Auto-Suggest" in Perfect Layout decides like this:
If the vertical spacing in the parts is already very wide, it will be kept (->use 200 EVPU).
If the spacing is already extremely dense and maybe even with collisions between staves, then it will also be set to s (standard) wide spacing (->use 200 EVPU).
If the spacing is dense, but probably ok, then the plug-in will keep a dense spacing (->use 80 EVPU).
If you load the "Tight Spacing" preset, then the vertical spacing will be set to just "20 EVPU".

If you want to define your own system distance in parts, deactivate "Auto-Suggest" and set your own value.

g.) Reserve Distance Between Bottom and Next Top Staff System Margin (Default: 70 EVPU)

After the score balancing algorithm the bottom system margin will be reduced by this value to allow easy manual shifting of the systems after Perfect Layout has finished.

Image 3: "Reserve Distance Between Bottom and Next Top Staff System Margin"

h.) Min. Vertical Space on Reflow Systems Across Pages (Default: 14 EVPU)

If "Reflow Systems Across Pages" is activated in the Finale preferences, Perfect Layout will re-arrange the systems across the pages and improve the layout. This "Min. Vertical Space" value defines the minimum distance between two systems. Usually you will never encounter this exact distance between systems in the end, as there is nearly always more space available on a page.
This is more a guide value that defines the general density of a page: the higher the value, the less number of systems will appear on a page.
E.g. the value 0 EVPU creates very dense parts, while a value of 50-70 EVPU generates a very loose vertical spacing.
This value is more relevant to (extracted) parts with lots of systems per page (see for example this demo video).
On conductor's scores with only one or two systems per page, this is not relevant as there is usually no reflow of systems across pages.

a.) Adjust Top System Margin to Max. Position of Top Staff

When activated this feature aligns the top element of the top staff with the page top margin (see in image 4 bottom).
This option is available separately for the score and the parts.
By default this is activated for the parts only. In the score it is usually preferred to have the top staff lines aligned.

If you have deactivated this option, make sure you have a nice "Distance Between Systems" value in your Finale (default) page format settings. This will be used/maintained otherwise.

Note: Make sure there is enough vertical space between your page text elements and the page top margin (e.g. page numbers, title) before you apply Perfect Layout. Otherwise you may get collisions when this feature is activated.

When Perfect Layout detects these page text/page top margin collisions, it automatically deactivates this pre-set feature.
In this case you have to manually (re-)activate this option to have it applied.

Image 4: The "Adjust Top System Margin to Max. Position of Top Staff" option
The enclosure of "Letter D" is aligned with the page top margin.

b.) Alignment at the Page Bottom

You can select different alignment techniques for the bottom of the page (see image 5 below). In this case alignment means "snap an element to the bottom page margin". That is also why it is important to set the bottom page margin to your needs before running the Perfect Layout plug-in.

The option "Fix Staff System Bottom Margin (Auto-Detect Lowest)" looks at all score pages, finds the lowest element at the bottom staff and uses the distance of this element to the bottom staff line as the "fix bottom margin". This guarantees that all staff lines of the bottom staff system align over all pages and that no element goes below the bottom page margin line. This default option works best in most cases.

If the bottom staff has very different distances to the bottom staff line (e.g. in modern piano works), it may work better to select the "Lowest Element On Bottom Staff" algorithm which aligns the lowest elements on all pages (and not the bottom staff line).

Both options are combined in the default option "Auto-Detect (Fix Staff System Bottom Margin or Lowest Element)": if the bottom margin is huge and very different on each page (e.g. contemporary piano scores), the "Lowest Element" algorithm is select, otherwise the "Fix Staff System Bottom Margin (Auto-Detect Lowest)".

Other options are:
"Fix Staff System Bottom Margin": same as above, but the distance is not auto-detected and can be entered manually.
"Bottom Staff Line": this option aligns the bottom staff line with the bottom page margin which means that all elements below the bottom staff line appear below the bottom page margin. It's the same as a "Fix Staff System Bottom Margin" with a value of 0 EVPU.

Image 5: Option Align Page Bottom Margin With

Note: the score balancing algorithm needs to take into account each Finale object (except page texts). Unfortunately JW Lua doesn't support all object properties yet, so the algorithm has some minor restrictions.
Currently unsupported or only partially supported objects are for graphic objects, mid-measure clefs, staff names, complex cross staff notes, shape articulations and smartshapes that span more then two systems.
To support some of these objects nevertheless dummy values are used which already lead to better results.

c.) Option: Auto-Adjust Bottom Margin for Colliding Page Texts on Bottom of First Page (e.g. Copyright Text)

Perfect Layout aligns the bottom system with the page bottom margin. So you need to make sure that all copyright text, page numbers, etc. are placed below the page bottom margin in order to avoid collisions with the score.
Perfect Layout's Auto-Adjust Bottom Margin for Colliding Page Texts on Bottom of First Page automatically adjusts the page bottom margin on the first page with systems (i.e. where usually the copyright texts are).

By default it generates a distance of 56 EVPU between the page bottom margin and the page text (see image 6 below).
The distance is set with the Bottom Margin to Page Text Distance parameter.

Image 6: Option Auto-Adjust Bottom Margin for Colliding Page Texts on Bottom of First Page

d.) Option: Force Spread to Page Bottom Margin

While the Max. Distance Between Staves value (470 EVPU by default) usually defines the maximum distance between staves, this value can be overridden by activating Force Spread to Page Bottom Margin. This gives so much space between staves until the system(s) are stretched until the page bottom margin(see image 7).

Image 7:
Left: By default 470 EVPUs maximum distance between staves
Right: Force Spread to Page Bottom Margin activated

e.) Option: Distribute Single Staff Systems Evenly Over Last Two Pages if at Least (5) Systems on Last Page

Similar to the previous option "Force Spread to Page Bottom Margin" which is meant for scores, this option is meant for single staff parts.
However, it only affects the last two pages of a part.
When activated (by default), this feature distributes all systems on the last two pages evenly.
When deactivated, it's possible that the last page only has very few systems which only fill the top part the page.

The minimum number of necessary systems on the last page can be adjusted. By default it is set to 5 staff systems.
This means: the feature will not be activated if there are only 4 systems on the last page.

Image 8: Distribute 1-Staff Systems Evenly Over the Last Two Pages

a.) Improved Measure Layout per System

The measure layout in parts is currently based on seven rules in Perfect Layout (PL).
While Perfect Layout version 2 and version 3 both work on extracted parts, while version 3 also processes linked parts.

1.) The parts layout of a score generated by PL is based on the measures manually set per system prior to running the program.
PL will not reset the measures per system.
For example, if you put five measures in Trumpet 1 system 1 and six measures in Trumpet 2 system 1 while both have the same notes, PL will keep this and not unify it.

If you need a certain part style like broadway/musical, Hollywood film music or jazz, make sure to get the measure layout done prior to running PL (like 4 bars per system, multi-measure rests spanning a whole system, etc.).

2.) The parts layout mainly relies on Finale's music spacing algorithms. In a few cases PL's own spacing is added (e.g. for chords and multi-layer note collisions).
Music Spacing is only applied to a part if one of the options under "Optimize->Options Spacing Settings" is activated and true for that part.
This means the music spacing will be either applied:
- always ("Always Apply Music (Re-)Spacing) or
- if there any chord symbols are found or
- if major spacing settings change with the "Optimize->Optimize Spacing Settings" option.

3.) PL can shift measures to the previous/next system if there are horizontal collisions otherwise (especially between chords or tempo mark expressions).
But this is only performed if "Reflow Across Systems" is activated in Finale's preferences or if the measure layout has been redone significantly in PL.
The latter would be for example the case, if no multi-measure rests had been created before running PL and there were many multi-measure rests in that part which would affect most systems.

4.) With version 3.x of the software, PL can now to shift a new section start to the previous or next system if it is preceded by a double barline or a repeat bar and if it is either the first or last bar of the current system.
This feature is only enabled if "Reflow Across Systems" is activated in Finale's preferences.
To successfully shift the measure, there must be sufficient horizontal space in the system, which can be checked by looking at the horizontal stretch value after the shift - it must be at least 0.95 or higher.
In certain cases, the measure may not shift (e.g. a single-measure crescendo after a multi-measure rest that leads into a new section after the barline, or a rehearsal or tempo mark at the start of the next system).

5.) PL optimizes the linked parts for good page turns, if the part has at least two pages and "Systems->Optimize Page Breaks with Rest Bars" is activated.
For detailed info see the next section b).

6.) If the final system has only one (narrow) measure and there is enough space, PL will shift the final measure to the previous system.

7.) If PL detects coda measures in the score (either through coda expressions or with repeat text elements), it will begin a new system in the parts with the coda measure.
To make the beginning of the coda more obvious, the system can also be shifted down further than usual (Systems->"Shift Coda System Down by").

b.) Page Breaks for Easy Page Turns

In parts with only one staff Perfect Layout v3 can optimize the system and measure layout for easy page turns via the option Optimize Page Breaks with Rests.
This feature analyzes the last systems on a page and looks for good page breaks with multi-measure rests, cue notes sections or longer rests within a measure.

First you have to determine where Perfect Layout should add page breaks.
By default Perfect Layout will add them on the odd (right) pages (Option: "On Odd (Right) Pages").
But you can also select the even (left) or both pages.

There is also the option "Only Optimize if Number of Staff Systems is at Least X".
It automatically deactivates the page break feature on parts with less than X systems (e.g. if the part only has two pages).

Perfect Layout only takes into account rests in the first or second bar of a system, or in the last or next-to-last bar.
I.e. a single multi-measure rest in the middle of a system with at least 5 bars is currently not shifted to the end of a system, because it is very likely that it will influence more than one subsequent system.

However, you can allow "Mid-System Multi-Measure Rests" for the page break if you activate one of these two options:
1.) Always Accept Mid-System Multi-Measure Rests: the first system with a multi-measure rest found in the middle of a system would be used for the page break, if the subsequent systems didn't have rests for a good page break.
2.) Prefer Mid-System Multi-Measure Rests over Single Empty Measures (in PL Gold only): like 1.), but only if there were no previous or subsequent systems with multi-measure rests at the start or end of the system.

Note: in these case of mid-system multi-measure rests Perfect Layout uses the system for the page break, but it doesn't shift the rest bars to the end of the system automatically. Because this will usually lead to music spacing problems or other collisions.
Here Perfect Layout only supports the search for page breaks:
you have to shift the multi-measure rest bars manually to the end of the system after Perfect Layout.

BTW, that is also why these two options are deactivated by default.
However, they allow for more complex page turns which may be required if there are only very few rests.

In Perfect Layout Gold you can control in how many systems Perfect Layout will search for rests through the option "Max. Number of Systems to Search in for Good Page Breaks". By default (and in PL Silver) this value is 4.

Perfect Layout refines its search in several steps:
1.) First it looks for a multi-measure rest that spans at least x bars. In PL Gold x is defined in "Preferred Minimum Number of Empty Measures at Page Break". By default and in PL Silver it is 2.
2.) If it doesn't find such a rest, it will reduce the number of bars (until x=1) and try again.
3.) If it's only one bar, it will first search with for one empty bar with adjacent rests in the previous bar.
4.) Then it will search for single rest bars.
5.) If it still hasn't found a full bar rest and "Allow Rests within Measures" is activated, it will search for long rests at the end of a measure:
In step one it searches for rests that span at least 3072 EDU (dotted half note - set with the "Minimum Rest Duration" option), in step two for rests that span at least 2048 EDU (half note, set with the "If not found, check for" option).
6.) If it still hasn't found a rest bar, it will finally search for mid-system multi-measure rests, even if the two mid-system options are not activated.

Rests at the end of a system are preferred over rests at the beginning of a system.
A rest at the start of a new page will not be visible to the musician before the page turn. So, if possible, this should be avoided.

Image 9: Rest priorities for good page breaks:
The first multi-measure rest in the second system (second measure) could be preferred over the second multi-measure rest (fifth measure of the second system) as it only requires shifting a whole note to the previous system, instead of shifting four quarter notes to the next system.
Perfect Layout decides which rest to take dependent on the system contents (e.g. the density of the music spacing).

If Perfect Layout has found a good page break above the current last system of the page, the number of systems on that page will be reduced.
Dependent on the number of reduced systems, Perfect Layout will either automatically add blank space at the bottom of the page (page break found many systems before end of page) or move systems from the previous page to the page with the page break (page break found close to end of page), so that the overall look will still be visually balanced.

If Perfect Layout has found a good page break in the second or next-to-last measure of a system, it tries to move it to the start or to the end of the system.
This is possible in most cases.
However, there may be scenarios where this is not possible or where it's not guaranteed that it looks good.
In these cases you should have a final look at these page breaks and move the measures manually and/or correct some minor collisions.
Perfect Layout adds a message to the log file and also displays a warning message on the screen at the end of processing.

Note 1: The page break feature is only available if "Reflow Systems Across Pages" is activated in Finale's Preferences->Edit and if "Systems->Optimize Staff/System Distances" is activated in Perfect Layout.
Note 2: The feature currently doesn't work on parts with more than one staff (e.g. piano parts or the full score).
The coda system is automatically shifted down for better readability (Option: "Shift Coda System Down"). The algorithm looks for repeat elements or text expressions with the user-defined keyword ("Coda" by default).
If the algorithm detects this word at the beginning of a system, it will move the system down by the given value (120 EVPUs by default). If there is not enough space on the page, the score balancing algorithm will probably decrease the distance.
Perfect Layout can also handle score files with several movements.

However, if possible, it is recommended to avoid large multi-movement scores in Finale with more than 1000 bars and more than 30 instruments as Finale (and Perfect Layout) becomes rather slow when handling these huge files.

Please make sure that the start of the new movement is easily visible and thus can be detected automatically by Perfect Layout.
To do so, if possible:
- use a large movement title (either as page text, as measure text or as a text expression)
- if the movement doesn't start on a new page, give a little more space to the system above
- activate the "Begin a new system" option on the first measure of a new movement in Finale's Measure Attributes dialog and answer "No" when asked if Perfect Layout should remove all "Begin a new system" attributes.

Here is an example video of optimizing a multi-movement score with text expressions as movement titles with Perfect Layout.