[freetype2-demos] master 38db2c5 4/4: [ftinspect] Start implementation of `showFont'.

[Werner LEMBERG]

branch: master
commit 38db2c5bd02611a7df7d38745345c0a4dc824c86
Author: Werner Lemberg <address@hidden>
Commit: Werner Lemberg <address@hidden>

    [ftinspect] Start implementation of `showFont'.
    
    * src/ftinspect.cpp (MainGUI::loadFonts): Call `showFont'.
    (MainGUI:closeFont): Fix logic and call `showFont'.
    (MainGUI::showFont): New method.  Doesn't display something yet, but
    font navigation buttons are fully functional now.
    (MainGUI::previousFont, MainGUI::nextFont, MainGUI::previousFace,
    MainGUI::nextFace, MainGUI::previousInstance,
    MainGUI::nextInstance): Call `showFont'.
    
    * src/ftinspect.h (MainGUI): Updated.
---
 ChangeLog         |   14 ++++++++
 src/ftinspect.cpp |   96 +++++++++++++++++++++++++++++++++++++++++++++++------
 src/ftinspect.h   |    1 +
 3 files changed, 100 insertions(+), 11 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index efb8238..add3ea7 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,19 @@
 2016-05-05  Werner Lemberg  <address@hidden>
 
+       [ftinspect] Start implementation of `showFont'.
+
+       * src/ftinspect.cpp (MainGUI::loadFonts): Call `showFont'.
+       (MainGUI:closeFont): Fix logic and call `showFont'.
+       (MainGUI::showFont): New method.  Doesn't display something yet, but
+       font navigation buttons are fully functional now.
+       (MainGUI::previousFont, MainGUI::nextFont, MainGUI::previousFace,
+       MainGUI::nextFace, MainGUI::previousInstance,
+       MainGUI::nextInstance): Call `showFont'.
+
+       * src/ftinspect.h (MainGUI): Updated.
+
+2016-05-05  Werner Lemberg  <address@hidden>
+
        [ftinspect] Add methods to get number of faces and instances.
 
        * src/ftinspect.cpp (Engine::numFaces, Engine::numInstances): New
diff --git a/src/ftinspect.cpp b/src/ftinspect.cpp
index ec2b157..2170b21 100644
--- a/src/ftinspect.cpp
+++ b/src/ftinspect.cpp
@@ -270,9 +270,7 @@ MainGUI::loadFonts()
   if (oldSize < fonts.size())
     currentFontIndex = oldSize;
 
-  checkCurrentFontIndex();
-
-  // XXX trigger redisplay
+  showFont();
 }
 
 
@@ -284,9 +282,79 @@ MainGUI::closeFont()
   if (currentFontIndex >= fonts.size())
     currentFontIndex--;
 
-  checkCurrentFontIndex();
+  if (currentFontIndex < 0
+      || fonts[currentFontIndex].numInstancesList.isEmpty())
+  {
+    currentFaceIndex = -1;
+    currentInstanceIndex = -1;
+  }
+  else
+  {
+    currentFaceIndex = 0;
+    currentInstanceIndex = 0;
+  }
+
+  showFont();
+}
+
+
+void
+MainGUI::showFont()
+{
+  if (currentFontIndex < 0)
+    return;
+
+  // we do lazy evaluation as much as possible
+
+  Font& font = fonts[currentFontIndex];
 
-  // XXX trigger redisplay
+  // if not yet available, extract the number of faces and indices
+  // for the current font
+
+  if (font.numInstancesList.isEmpty())
+  {
+    int numFaces = engine->numFaces(currentFontIndex);
+
+    if (numFaces > 0)
+    {
+      for (int i = 0; i < numFaces; i++)
+        font.numInstancesList.append(-1);
+
+      currentFaceIndex = 0;
+      currentInstanceIndex = 0;
+    }
+    else
+    {
+      // we use `numInstancesList' with a single element set to zero
+      // to indicate either a non-font or a font FreeType couldn't load;
+      font.numInstancesList.append(0);
+
+      currentFaceIndex = -1;
+      currentInstanceIndex = -1;
+    }
+  }
+
+  // value -1 in `numInstancesList' means `not yet initialized'
+  else if (font.numInstancesList[currentFaceIndex] < 0)
+  {
+    int numInstances = engine->numInstances(currentFontIndex,
+                                            currentFaceIndex);
+
+    // XXX? we ignore errors
+    if (numInstances < 0)
+      numInstances = 1;
+
+    font.numInstancesList[currentFaceIndex] = numInstances;
+
+    // instance index 0 represents a face without an instance;
+    // consequently, `n' instances are enumerated from 1 to `n'
+    // (instead of having indices 0 to `n-1')
+    currentInstanceIndex = 0;
+  }
+
+  checkCurrentFontIndex();
+  checkCurrentFaceIndex();
+  checkCurrentInstanceIndex();
 }
 
 
@@ -474,7 +542,9 @@ MainGUI::previousFont()
   if (currentFontIndex > 0)
   {
     currentFontIndex--;
-    checkCurrentFontIndex();
+    currentFaceIndex = 0;
+    currentInstanceIndex = 0;
+    showFont();
   }
 }
 
@@ -485,7 +555,9 @@ MainGUI::nextFont()
   if (currentFontIndex < fonts.size() - 1)
   {
     currentFontIndex++;
-    checkCurrentFontIndex();
+    currentFaceIndex = 0;
+    currentInstanceIndex = 0;
+    showFont();
   }
 }
 
@@ -496,7 +568,8 @@ MainGUI::previousFace()
   if (currentFaceIndex > 0)
   {
     currentFaceIndex--;
-    checkCurrentFaceIndex();
+    currentInstanceIndex = 0;
+    showFont();
   }
 }
 
@@ -509,7 +582,8 @@ MainGUI::nextFace()
   if (currentFaceIndex < numFaces - 1)
   {
     currentFaceIndex++;
-    checkCurrentFaceIndex();
+    currentInstanceIndex = 0;
+    showFont();
   }
 }
 
@@ -520,7 +594,7 @@ MainGUI::previousInstance()
   if (currentInstanceIndex > 0)
   {
     currentInstanceIndex--;
-    checkCurrentInstanceIndex();
+    showFont();
   }
 }
 
@@ -534,7 +608,7 @@ MainGUI::nextInstance()
   if (currentInstanceIndex < numInstances - 1)
   {
     currentInstanceIndex++;
-    checkCurrentInstanceIndex();
+    showFont();
   }
 }
 
diff --git a/src/ftinspect.h b/src/ftinspect.h
index eacc196..61dde19 100644
--- a/src/ftinspect.h
+++ b/src/ftinspect.h
@@ -294,6 +294,7 @@ private:
   void createStatusBar();
   void readSettings();
   void setDefaults();
+  void showFont();
   void writeSettings();
 };