fix(Layout): Fix hiding first instrument causing shift of lyrics, dynamics, etc (#83, #61)

* fixed the layout issue when you hide a instrument

* added null check

* data: add test_layout_first_measure_hidden.musicxml

Co-authored-by: Ethan Yan (@Elitebigboss90)
Co-authored-by: sschmidTU <s.schmid@phonicscore.com>

src/MusicalScore/Graphical/VexFlow/VexFlowMusicSheetCalculator.ts

@@ -103,9 +103,9 @@ export class VexFlowMusicSheetCalculator extends MusicSheetCalculator {
       if (!verticalMeasureList || !verticalMeasureList[0]) {
         continue;
       }
-      const firstMeasure: VexFlowMeasure = verticalMeasureList[0] as VexFlowMeasure;
+      const firstVisibleMeasure: VexFlowMeasure = verticalMeasureList.find(measure => measure?.isVisible()) as VexFlowMeasure;
       // first measure has formatting method as lambda function object, but formats all measures. TODO this could be refactored
-      firstMeasure.format();
+      firstVisibleMeasure.format();
       for (const measure of verticalMeasureList) {
         for (const staffEntry of measure.staffEntries) {
           (<VexFlowStaffEntry>staffEntry).calculateXPosition();

test/data/test_layout_first_measure_hidden.musicxml

@@ -0,0 +1,224 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE score-partwise PUBLIC "-//Recordare//DTD MusicXML 3.1 Partwise//EN" "http://www.musicxml.org/dtds/partwise.dtd">
+<score-partwise version="3.1">
+  <work>
+    <work-title>test_layout_first_measure_hidden</work-title>
+    </work>
+  <identification>
+    <encoding>
+      <software>MuseScore 3.6.2</software>
+      <encoding-date>2022-09-09</encoding-date>
+      <supports element="accidental" type="yes"/>
+      <supports element="beam" type="yes"/>
+      <supports element="print" attribute="new-page" type="yes" value="yes"/>
+      <supports element="print" attribute="new-system" type="yes" value="yes"/>
+      <supports element="stem" type="yes"/>
+      </encoding>
+    </identification>
+  <defaults>
+    <scaling>
+      <millimeters>6.99911</millimeters>
+      <tenths>40</tenths>
+      </scaling>
+    <page-layout>
+      <page-height>1596.77</page-height>
+      <page-width>1233.87</page-width>
+      <page-margins type="even">
+        <left-margin>85.7252</left-margin>
+        <right-margin>85.7252</right-margin>
+        <top-margin>85.7252</top-margin>
+        <bottom-margin>85.7252</bottom-margin>
+        </page-margins>
+      <page-margins type="odd">
+        <left-margin>85.7252</left-margin>
+        <right-margin>85.7252</right-margin>
+        <top-margin>85.7252</top-margin>
+        <bottom-margin>85.7252</bottom-margin>
+        </page-margins>
+      </page-layout>
+    <word-font font-family="Edwin" font-size="10"/>
+    <lyric-font font-family="Edwin" font-size="10"/>
+    </defaults>
+  <credit page="1">
+    <credit-type>title</credit-type>
+    <credit-words default-x="616.935" default-y="1511.05" justify="center" valign="top" font-size="22">test_layout_first_measure_hidden</credit-words>
+    </credit>
+  <part-list>
+    <part-group type="start" number="1">
+      <group-symbol>bracket</group-symbol>
+      </part-group>
+    <part-group type="start" number="2">
+      <group-symbol>square</group-symbol>
+      </part-group>
+    <score-part id="P1">
+      <part-name>Soprano 1</part-name>
+      <part-abbreviation>S. 1</part-abbreviation>
+      <score-instrument id="P1-I1">
+        <instrument-name>Soprano</instrument-name>
+        </score-instrument>
+      <midi-device id="P1-I1" port="1"></midi-device>
+      <midi-instrument id="P1-I1">
+        <midi-channel>1</midi-channel>
+        <midi-program>53</midi-program>
+        <volume>78.7402</volume>
+        <pan>0</pan>
+        </midi-instrument>
+      </score-part>
+    <score-part id="P2">
+      <part-name>Soprano 2</part-name>
+      <part-abbreviation>S. 2</part-abbreviation>
+      <score-instrument id="P2-I1">
+        <instrument-name>Soprano</instrument-name>
+        </score-instrument>
+      <midi-device id="P2-I1" port="1"></midi-device>
+      <midi-instrument id="P2-I1">
+        <midi-channel>2</midi-channel>
+        <midi-program>53</midi-program>
+        <volume>78.7402</volume>
+        <pan>0</pan>
+        </midi-instrument>
+      </score-part>
+    <part-group type="stop" number="2"/>
+    <part-group type="stop" number="1"/>
+    </part-list>
+  <part id="P1">
+    <measure number="1" width="912.67">
+      <print>
+        <system-layout>
+          <system-margins>
+            <left-margin>116.03</left-margin>
+            <right-margin>0.00</right-margin>
+            </system-margins>
+          <top-system-distance>170.00</top-system-distance>
+          </system-layout>
+        </print>
+      <attributes>
+        <divisions>1</divisions>
+        <key>
+          <fifths>0</fifths>
+          </key>
+        <time>
+          <beats>3</beats>
+          <beat-type>4</beat-type>
+          </time>
+        <clef>
+          <sign>G</sign>
+          <line>2</line>
+          </clef>
+        </attributes>
+      <note default-x="86.02" default-y="-35.00">
+        <pitch>
+          <step>F</step>
+          <octave>4</octave>
+          </pitch>
+        <duration>1</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+        <stem>up</stem>
+        <lyric number="1" default-x="6.50" default-y="-40.00" relative-y="-30.00">
+          <syllabic>single</syllabic>
+          <text>One</text>
+          </lyric>
+        </note>
+      <note default-x="358.02" default-y="-30.00">
+        <pitch>
+          <step>G</step>
+          <octave>4</octave>
+          </pitch>
+        <duration>1</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+        <stem>up</stem>
+        <lyric number="1" default-x="6.50" default-y="-40.00" relative-y="-30.00">
+          <syllabic>single</syllabic>
+          <text>Two</text>
+          </lyric>
+        </note>
+      <note default-x="630.02" default-y="-25.00">
+        <pitch>
+          <step>A</step>
+          <octave>4</octave>
+          </pitch>
+        <duration>1</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+        <stem>up</stem>
+        <lyric number="1" default-x="6.50" default-y="-40.00" relative-y="-30.00">
+          <syllabic>single</syllabic>
+          <text>Three</text>
+          </lyric>
+        </note>
+      <barline location="right">
+        <bar-style>light-heavy</bar-style>
+        </barline>
+      </measure>
+    </part>
+  <part id="P2">
+    <measure number="1" width="912.67">
+      <print>
+        <staff-layout number="1">
+          <staff-distance>115.95</staff-distance>
+          </staff-layout>
+        </print>
+      <attributes>
+        <divisions>1</divisions>
+        <key>
+          <fifths>0</fifths>
+          </key>
+        <time>
+          <beats>3</beats>
+          <beat-type>4</beat-type>
+          </time>
+        <clef>
+          <sign>G</sign>
+          <line>2</line>
+          </clef>
+        </attributes>
+      <note default-x="86.02" default-y="-205.95">
+        <pitch>
+          <step>C</step>
+          <octave>4</octave>
+          </pitch>
+        <duration>1</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+        <stem>up</stem>
+        <lyric number="1" default-x="6.50" default-y="-50.32" relative-y="-30.00">
+          <syllabic>single</syllabic>
+          <text>One</text>
+          </lyric>
+        </note>
+      <note default-x="358.02" default-y="-200.95">
+        <pitch>
+          <step>D</step>
+          <octave>4</octave>
+          </pitch>
+        <duration>1</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+        <stem>up</stem>
+        <lyric number="1" default-x="6.50" default-y="-50.32" relative-y="-30.00">
+          <syllabic>single</syllabic>
+          <text>Two</text>
+          </lyric>
+        </note>
+      <note default-x="630.02" default-y="-195.95">
+        <pitch>
+          <step>E</step>
+          <octave>4</octave>
+          </pitch>
+        <duration>1</duration>
+        <voice>1</voice>
+        <type>quarter</type>
+        <stem>up</stem>
+        <lyric number="1" default-x="6.50" default-y="-50.32" relative-y="-30.00">
+          <syllabic>single</syllabic>
+          <text>Three</text>
+          </lyric>
+        </note>
+      <barline location="right">
+        <bar-style>light-heavy</bar-style>
+        </barline>
+      </measure>
+    </part>
+  </score-partwise>