fix win32 font drawing

src/dlangui/graphics/fonts.d

@@ -226,8 +226,10 @@ class FontManager {
     static __gshared FontManager _instance;
     /// sets new font manager singleton instance
     static @property void instance(FontManager manager) {
-		if (_instance !is null)
+		if (_instance !is null) {
 			destroy(_instance);
+            _instance = null;
+        }
         _instance = manager;
     }
     /// returns font manager singleton instance

src/dlangui/graphics/ftfonts.d

@@ -266,6 +266,9 @@ private class FreeTypeFontFile {
                 for (int i = 0; i < sz; i++)
                     glyph.glyph[i] = bitmap.buffer[i];
             }
+            version (USE_OPENGL) {
+                glyph.id = nextGlyphId();
+            }
         }
         return true;
     }

src/dlangui/platforms/windows/win32fonts.d

@@ -203,6 +203,37 @@ class Win32Font : Font {
 		}
 	}
 
+    static if (true) {
+	    override int measureText(const dchar[] text, ref int[] widths, int maxWidth) {
+		    if (text.length == 0)
+			    return 0;
+		    const dchar * pstr = text.ptr;
+		    uint len = cast(uint)text.length;
+            if (widths.length < len)
+                widths.length = len;
+            int x = 0;
+            int charsMeasured = 0;
+		    for (int i = 0; i < len; i++) {
+			    Glyph * glyph = getCharGlyph(text[i], true); // TODO: what is better
+			    if (glyph is null) {
+                    // if no glyph, use previous width - treat as zero width
+                    widths[i] = i > 0 ? widths[i-1] : 0;
+				    continue;
+                }
+                int w = x + glyph.width; // using advance
+                int w2 = x + glyph.originX + glyph.blackBoxX; // using black box
+                if (w < w2) // choose bigger value
+                    w = w2;
+                widths[i] = w;
+                x += glyph.width;
+                charsMeasured = i + 1;
+                if (x > maxWidth)
+                    break;
+            }
+		    return charsMeasured;
+	    }
+    } else {
+
 	    override int measureText(const dchar[] text, ref int[] widths, int maxWidth) {
 		    if (_hfont is null || _drawbuf is null || text.length == 0)
 			    return 0;
@@ -236,6 +267,7 @@ class Win32Font : Font {
 		    }
 		    return measured;
 	    }
+    }
 
 	bool create(FontDef * def, int size, int weight, bool italic) {
         if (!isNull())
@@ -300,7 +332,7 @@ class Win32FontManager : FontManager {
 	/// initialize in constructor
     this() {
         Log.i("Creating Win32FontManager");
-        instance = this;
+        //instance = this;
         init();
     }
     ~this() {

src/dlangui/platforms/windows/winapp.d

@@ -201,6 +201,7 @@ class Win32Window : Window {
 
     version (USE_OPENGL) {
         private void paintUsingOpenGL() {
+            Log.d("paintUsingOpenGL()");
             // hack to stop infinite WM_PAINT loop
             PAINTSTRUCT ps;
             HDC hdc2 = BeginPaint(_hwnd, &ps);
@@ -222,12 +223,14 @@ class Win32Window : Window {
 			float r = ((_backgroundColor >> 16) & 255) / 255.0f;
 			float g = ((_backgroundColor >> 8) & 255) / 255.0f;
 			float b = ((_backgroundColor >> 0) & 255) / 255.0f;
+            Log.d("paintUsingOpenGL() - clearing buffer");
             glClearColor(r, g, b, a);
             glClear(GL_COLOR_BUFFER_BIT);
 
+            Log.d("paintUsingOpenGL() - creating drawbuf");
             GLDrawBuf buf = new GLDrawBuf(_dx, _dy, false);
             buf.beforeDrawing();
-            if (false) {
+            static if (false) {
                 // for testing for render
                 buf.fillRect(Rect(100, 100, 200, 200), 0x704020);
                 buf.fillRect(Rect(40, 70, 100, 120), 0x000000);
@@ -241,8 +244,9 @@ class Win32Window : Window {
             } else {
                 onDraw(buf);
             }
+            Log.d("paintUsingOpenGL() - calling buf.afterDrawing");
             buf.afterDrawing();
-            //Log.d("onPaint() end drawing opengl");
+            Log.d("onPaint() end drawing opengl");
             SwapBuffers(hdc);
             wglMakeCurrent(hdc, null);
         }
@@ -595,8 +599,8 @@ int myWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int
 
     // use Win32 font manager
     if (FontManager.instance is null) {
-	    Win32FontManager fontMan = new Win32FontManager();
+	    //Win32FontManager fontMan = new Win32FontManager();
-	    FontManager.instance = fontMan;
+	    FontManager.instance = new Win32FontManager();
     }
 
 	currentTheme = createDefaultTheme();