Fixed left offset parameter handling for center/right align string drawing. A brief note about string drawing, offset and display width is added in the WFont.h

JGE/src/JLBFont.cpp

@@ -113,10 +113,22 @@ void JLBFont::DrawString(const char *string, float x, float y, int align, float
 
 	float width = GetStringWidth(string);
 
-	if (align == JGETEXT_RIGHT)
+	if (align == JGETEXT_RIGHT) {
+		if (displayWidth) {
+			dx0 -= displayWidth;
+			leftOffset += width - displayWidth;
+		}
+		else
 			dx0 -= width;
-	else if (align == JGETEXT_CENTER)
+	}
+	else if (align == JGETEXT_CENTER) {
+		if (displayWidth) {
+			dx0 -= displayWidth/2;
+			leftOffset += width/2 - displayWidth/2;
+		}
+		else
 			dx0 -= width/2;
+	}
 
 	float dx = floorf(dx0);
 	dy = floorf(dy);
@@ -147,7 +159,7 @@ void JLBFont::DrawString(const char *string, float x, float y, int align, float
       if (leftOffset < 0){
         dx-=leftOffset;
         leftOffset = 0;
-        continue;
+        //continue;
       }else if (leftOffset - delta > 0){
         leftOffset -= delta;
         p++;
@@ -160,7 +172,8 @@ void JLBFont::DrawString(const char *string, float x, float y, int align, float
         charWidth = (delta/mScale) - mTracking;
       }
     }
-    else if (displayWidth){
+    if (displayWidth){
+    // This condiction must be tested indepently in the case leftOffset and displayWidth need a fix at the same time.
       if (dx > x0+displayWidth)  return;
       if (dx+delta > x0+displayWidth) {
         delta = x0 + displayWidth - dx;

projects/mtg/include/WFont.h

@@ -28,8 +28,14 @@ class WFont
 public:
   int mFontID;
   // Rendering text to screen.
-  virtual void DrawString(const char *s, float x, float y, int align=JGETEXT_LEFT, float leftOffset = 0, float width = 0) = 0;
+  // Note:
-  virtual void DrawString(std::string s, float x, float y, int align=JGETEXT_LEFT, float leftOffset = 0, float width = 0) = 0;
+  // align=JGETEXT_LEFT,   string region (x-leftOffset, x-leftOffset+StringWidth), display window (x, x+displayWidth)
+  // align=JGETEXT_CENTER, string region (x-leftOffset-StringWidth/2, x-leftOffset+StringWidth/2), display window (x-displayWidth/2, x+displayWidth/2)
+  // align=JGETEXT_RIGHT,  string region (x-leftOffset-StringWidth, x-leftOffset), display window (x-displayWidth, x)
+  // Only when width is NOT zero, characters outside the display window are not rendered.
+  // 
+  virtual void DrawString(const char *s, float x, float y, int align=JGETEXT_LEFT, float leftOffset = 0, float displayWidth = 0) = 0;
+  virtual void DrawString(std::string s, float x, float y, int align=JGETEXT_LEFT, float leftOffset = 0, float displayWidth = 0) = 0;
   // Set font color.
   virtual void SetColor(PIXEL_TYPE color) = 0;
   // Get font color.

projects/mtg/src/WFont.cpp

@@ -386,9 +386,19 @@ void WFBFont::DrawString(const char *s, float x, float y, int align, float leftO
     switch (align)
     {
     case JGETEXT_RIGHT:
+        if (width) {
+            x -= width;
+            leftOffset += GetStringWidth(s) - width;
+        }
+        else
             x -= GetStringWidth(s);
         break;
     case JGETEXT_CENTER:
+        if (width) {
+            x -= width/2;
+            leftOffset += GetStringWidth(s)/2 - width/2;
+        }
+        else
             x -= GetStringWidth(s)/2;
         break;
     case JGETEXT_LEFT:
@@ -473,7 +483,7 @@ void WFBFont::DrawString(const char *s, float x, float y, int align, float leftO
                         charW = delta / mScale;
                     }
                 }
-                else if (width)
+                if (width)
                 {
                     if (xx > x + width) return;
                     if (xx + delta > x + width)
@@ -778,9 +788,19 @@ void WGBKFont::DrawString(const char *s, float x, float y, int align, float left
     switch (align)
     {
     case JGETEXT_RIGHT:
+        if (width) {
+            x -= width;
+            leftOffset += GetStringWidth(s) - width;
+        }
+        else
             x -= GetStringWidth(s);
         break;
     case JGETEXT_CENTER:
+        if (width) {
+            x -= width/2;
+            leftOffset += GetStringWidth(s)/2 - width/2;
+        }
+        else
             x -= GetStringWidth(s)/2;
         break;
     case JGETEXT_LEFT:
@@ -882,7 +902,7 @@ void WGBKFont::DrawString(const char *s, float x, float y, int align, float left
                         charW = delta / mScale;
                     }
                 }
-                else if (width)
+                if (width)
                 {
                     if (xx > x + width) return;
                     if (xx + delta > x + width)