Add angle measurement

data/io.github.herve4m.Length.gschema.xml.in

@@ -76,6 +76,30 @@
       </description>
     </key>
 
+    <key name="show-markings" type="b">
+      <default>true</default>
+      <summary>Show the Ruler Markings</summary>
+      <description>Display the ticks on the ruler.</description>
+    </key>
+
+    <key name="show-grid" type="b">
+      <default>true</default>
+      <summary>Show the Grid</summary>
+      <description>Display a grid when the ruler is expanded.</description>
+    </key>
+
+    <key name="show-diagonals" type="b">
+      <default>false</default>
+      <summary>Show Dialogals</summary>
+      <description>Display the diagonal rulers.</description>
+    </key>
+
+    <key name="show-angles" type="b">
+      <default>false</default>
+      <summary>Show Angles</summary>
+      <description>Display the diagonal angles.</description>
+    </key>
+
     <key name="use-default-font" type="b">
       <default>true</default>
       <summary>Use default font</summary>

data/io.github.herve4m.Length.metainfo.xml.in.in

@@ -41,27 +41,27 @@
 
   <screenshots>
     <screenshot type="default">
-      <image>https://raw.githubusercontent.com/herve4m/length/refs/tags/@version@/data/media/screenshots/horizontal-pixels.png</image>
+      <image>https://raw.githubusercontent.com/herve4m/length/main/data/media/screenshots/horizontal-pixels.png</image>
       <caption>Horizontal view of Length with pixels as units</caption>
     </screenshot>
     <screenshot>
-      <image>https://raw.githubusercontent.com/herve4m/length/refs/tags/@version@/data/media/screenshots/vertical-inches.png</image>
+      <image>https://raw.githubusercontent.com/herve4m/length/main/data/media/screenshots/vertical-inches.png</image>
       <caption>Vertical view of Length with inches as units</caption>
     </screenshot>
     <screenshot>
-      <image>https://raw.githubusercontent.com/herve4m/length/refs/tags/@version@/data/media/screenshots/menu.png</image>
+      <image>https://raw.githubusercontent.com/herve4m/length/main/data/media/screenshots/menu.png</image>
       <caption>Length main menu</caption>
     </screenshot>
     <screenshot>
-      <image>https://raw.githubusercontent.com/herve4m/length/refs/tags/@version@/data/media/screenshots/preferences.png</image>
+      <image>https://raw.githubusercontent.com/herve4m/length/main/data/media/screenshots/preferences.png</image>
       <caption>Preferences window</caption>
     </screenshot>
     <screenshot>
-      <image>https://raw.githubusercontent.com/herve4m/length/refs/tags/@version@/data/media/screenshots/track-pointer.png</image>
+      <image>https://raw.githubusercontent.com/herve4m/length/main/data/media/screenshots/track-pointer.png</image>
       <caption>Pointer tracking enabled</caption>
     </screenshot>
     <screenshot>
-      <image>https://raw.githubusercontent.com/herve4m/length/refs/tags/@version@/data/media/screenshots/right-to-left.png</image>
+      <image>https://raw.githubusercontent.com/herve4m/length/main/data/media/screenshots/right-to-left.png</image>
       <caption>Right to left ruler orientation</caption>
     </screenshot>
   </screenshots>

data/ui/help-overlay.ui

@@ -24,7 +24,7 @@
     <child>
       <object class="GtkShortcutsSection">
         <property name="section-name">shortcuts</property>
-        <property name="max-height">20</property>
+        <property name="max-height">15</property>
         <child>
           <object class="GtkShortcutsGroup">
             <property name="title" translatable="yes" context="shortcut window">General</property>
@@ -58,6 +58,42 @@
           </object>
         </child>
 
+        <child>
+          <object class="GtkShortcutsGroup">
+            <property name="title" translatable="yes" context="shortcut window">Layers</property>
+            <child>
+              <object class="GtkShortcutsShortcut">
+                <property name="title" translatable="yes" context="shortcut window">Show/Hide Markings</property>
+                <property name="accelerator">m</property>
+              </object>
+            </child>
+            <child>
+              <object class="GtkShortcutsShortcut">
+                <property name="title" translatable="yes" context="shortcut window">Show/Hide Grid</property>
+                <property name="accelerator">g</property>
+              </object>
+            </child>
+            <child>
+              <object class="GtkShortcutsShortcut">
+                <property name="title" translatable="yes" context="shortcut window">Show/Hide Diagonals</property>
+                <property name="accelerator">i</property>
+              </object>
+            </child>
+            <child>
+              <object class="GtkShortcutsShortcut">
+                <property name="title" translatable="yes" context="shortcut window">Show/Hide Angles</property>
+                <property name="accelerator">a</property>
+              </object>
+            </child>
+            <child>
+              <object class="GtkShortcutsShortcut">
+                <property name="title" translatable="yes" context="shortcut window">Left-to-right/Right-to-left</property>
+                <property name="accelerator">d</property>
+              </object>
+            </child>
+          </object>
+        </child>
+
         <child>
           <object class="GtkShortcutsGroup">
             <property name="title" translatable="yes" context="shortcut window">Opacity</property>

data/ui/preferences.ui

@@ -76,6 +76,45 @@
           </object>
         </child>
 
+        <child>
+          <object class="AdwPreferencesGroup">
+            <property name="title" translatable="yes">Layers</property>
+
+            <child>
+              <object class="AdwSwitchRow" id="marking_switchrow">
+                <property name="title" translatable="yes">Ruler _Markings</property>
+                <property name="use-underline">true</property>
+                <signal name="notify::active" handler="_refresh_ui"/>
+              </object>
+            </child>
+
+            <child>
+              <object class="AdwSwitchRow" id="grid_switchrow">
+                <property name="title" translatable="yes">_Grid</property>
+                <property name="use-underline">true</property>
+                <property name="active" bind-source="marking_switchrow" bind-property="active" bind-flags="sync-create"/>
+                <signal name="notify::active" handler="_refresh_ui"/>
+              </object>
+            </child>
+
+            <child>
+              <object class="AdwSwitchRow" id="diagonal_switchrow">
+                <property name="title" translatable="yes">D_iagonals</property>
+                <property name="use-underline">true</property>
+                <signal name="notify::active" handler="_refresh_ui"/>
+              </object>
+            </child>
+
+            <child>
+              <object class="AdwSwitchRow" id="angle_switchrow">
+                <property name="title" translatable="yes">_Angles</property>
+                <property name="use-underline">true</property>
+                <signal name="notify::active" handler="_refresh_ui"/>
+              </object>
+            </child>
+          </object>
+        </child>
+
         <child>
           <object class="AdwPreferencesGroup">
             <property name="title" translatable="yes">Appearance</property>

help/C/adjusting.page

@@ -31,7 +31,7 @@
 
   <p>
     To align the ruler with the object's window, drag the ruler while pressing <key>Ctrl</key>.
-    When the ruler gets close to the object's edge, the rule snaps to the window.
+    When the ruler gets close to the object's edge, the ruler snaps to the window.
   </p>
 
   <p>

help/C/calibrating.page

@@ -35,7 +35,7 @@
 
   <p>
     In some environments, <app>Length</app> retrieves this information from the system.
-    Other environments to do provide that size.
+    Other environments do not provide that size.
     In that case, you must calibrate <app>Length</app> for you display:
   </p>
 

help/C/colors.page

@@ -22,7 +22,7 @@
 
     <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
 
-    <desc>Selecting the colors of the ruler.</desc>
+    <desc>Select the colors of the ruler.</desc>
   </info>
 
   <title>Changing Colors</title>
@@ -31,7 +31,7 @@
     <p><app>Length</app> in different colors</p>
   </media>
 
-  <p>You can change the color of ruler and the color of the markings.</p>
+  <p>You can change the color of the ruler and the color of the markings.</p>
 
   <steps>
     <item><p>Click the menu button (<media its:translate="no" type="image" src="figures/open-menu-symbolic.svg"/>) in the left-side corner of the ruler.</p></item>

help/C/direction.page

@@ -38,8 +38,10 @@
 
     <item><p>Go to <gui style="menuitem">Preferences</gui>.</p></item>
 
-    <item><p>In the <gui style="tab">General</gui> page, click the left-to-right direction button (<media its:translate="no" type="image" src="figures/direction-ltr-symbolic.svg"/>), or the right-to-left button (<media its:translate="no" type="image" src="figures/direction-rtl-symbolic.svg"/>).</p></item>
+    <item><p>In the <gui style="tab">General</gui> page, click the left-to-right direction button (<media its:translate="no" type="image" src="figures/direction-ltr-symbolic.svg"/>) or the right-to-left button (<media its:translate="no" type="image" src="figures/direction-rtl-symbolic.svg"/>).</p></item>
 
     <item><p>Close the <gui>Preferences</gui> dialog.</p></item>
   </steps>
+
+  <p>You can also switch direction by pressing <key>D</key>.</p>
 </page>

help/C/layers.page

@@ -0,0 +1,85 @@
+<page xmlns="http://projectmallard.org/1.0/"
+      xmlns:its="http://www.w3.org/2005/11/its"
+      type="topic"
+      id="layers">
+
+  <info>
+    <link type="guide" xref="index#preferences"/>
+
+    <revision pkgversion="0.4.0" docversion="0.1.0" version="0.1.0" date="2025-02-08" status="final"/>
+
+    <credit type="author copyright">
+      <name its:translate="no">Hervé Quatremain</name>
+      <years>2025</years>
+    </credit>
+
+    <!--
+    <credit type="translator">
+      <name its:translate="no">Your Name</name>
+      <years>2025</years>
+    </credit>
+    -->
+
+    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
+
+    <desc>Select the measuring tools.</desc>
+  </info>
+
+  <title>Selecting Measuring Tools</title>
+
+  <p><app>Length</app> provide several measuring tools organized in layers.</p>
+
+  <p>The markings layer displays the rulers markings.</p>
+
+  <media its:translate="no" type="image" src="figures/layer-markings.png">
+    <p>Ruler's markings</p>
+  </media>
+
+  <p>To help you measure large objects when the ruler is expanded, you can activate the grid.</p>
+
+  <media its:translate="no" type="image" src="figures/layer-grid.png">
+    <p>Ruler's grid</p>
+  </media>
+
+  <p>The diagonal layer displays diagonals rulers.</p>
+
+  <media its:translate="no" type="image" src="figures/layer-diagonals.png">
+    <p>Diagonal rulers</p>
+  </media>
+
+  <p>Activate the angle layer to measure angles.</p>
+
+  <media its:translate="no" type="image" src="figures/layer-angles.png">
+    <p>Measuring angles</p>
+  </media>
+
+  <p>
+    You can activate several layers for using several tools at the same time.
+    For example, the marking and grid layers are enabled by default.
+  </p>
+
+  <p>You activate layers from the <gui>Preferences</gui> dialog.</p>
+
+  <steps>
+    <item><p>Click the menu button (<media its:translate="no" type="image" src="figures/open-menu-symbolic.svg"/>) in the left-side corner of the ruler.</p></item>
+
+    <item><p>Go to <gui style="menuitem">Preferences</gui>.</p></item>
+
+    <item>
+      <p>In the <gui style="tab">General</gui> page, in the <gui style="group">Layers</gui> section, use the checkboxes to enable or disable the layers.</p>
+      <media its:translate="no" type="image" src="figures/layer-preferences.png">
+        <p>Activating layers</p>
+      </media>
+    </item>
+
+    <item><p>Close the <gui>Preferences</gui> dialog.</p></item>
+  </steps>
+
+  <p>Alternatively, use the keyboard shortcuts:</p>
+  <list>
+    <item><p><key>m</key> for the marking layer</p></item>
+    <item><p><key>g</key> for the grid layer</p></item>
+    <item><p><key>i</key> for the diagonal layer</p></item>
+    <item><p><key>a</key> for the angle layer</p></item>
+  </list>
+</page>

help/C/offset.page

@@ -25,7 +25,7 @@
     <desc>Change the unit origin.</desc>
   </info>
 
-  <title>Changing the Offset</title>
+  <title>Setting an Offset</title>
 
   <media type="image" src="figures/offset.png">
     <p>Changing the origin</p>

help/C/resizing.page

@@ -32,7 +32,7 @@
   </media>
 
   <p>
-    You can resize the ruler to adjust it to the object to measure.
+    You can resize the ruler for adjusting it to the object to measure.
     You resize the ruler by dragging the edges.
   </p>
 </page>

help/C/transparency.page

@@ -22,7 +22,7 @@
 
     <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
 
-    <desc>Adjust the transparency to measure objects behind the ruler.</desc>
+    <desc>Adjust the transparency for measuring objects behind the ruler.</desc>
   </info>
 
   <title>Adjusting Transparency</title>

help/C/units.page

@@ -32,7 +32,7 @@
     <p>Changing the ruler's unit</p>
   </media>
 
-  <p><app>Length</app> comes in several units that you can select from the <gui>Preferences</gui> dialog.</p>
+  <p><app>Length</app> comes with several units that you can select from the <gui>Preferences</gui> dialog.</p>
 
   <steps>
     <item><p>Click the menu button (<media its:translate="no" type="image" src="figures/open-menu-symbolic.svg"/>) in the left-side corner of the ruler.</p></item>
@@ -66,7 +66,7 @@
       In that case, you must calibrate <app>Length</app> for you display.
     </p>
     <p>
-      See <link xref="calibrating"/> for information on configuring <app>Length</app> for the size of your display.
+      See <link xref="calibrating"/> for more information about configuring <app>Length</app> for the size of your display.
     </p>
   </note>
 </page>

help/README-BUILD.md

@@ -10,6 +10,7 @@
 - Update the `help.pot` file from the pages in the `C` directory:
 
 ```
+$ cd help
 $ itstool -o help.pot ../help/C/*.page
 ```