Fix debug overlay for large cycle

No boundary protection existed previously, which corrupted the image
when there were more diffs per cycle to print than could fit into the
image. This change breaks the diffs into columns and draws as many as
can fit into the image.

3rd-party/info.cpp

@@ -1562,9 +1562,32 @@ void DrawDigit(PVideoFrame &dst, int x, int y, int num, int bYUY2)
 	}
 }
 
-void DrawString(PVideoFrame &dst, int x, int y, const char *s, int bYUY2) 
+void _DrawString(PVideoFrame &dst, int x, int y, const char *s, int bYUY2)
 {
 	for (int xx = 0; *s; ++s, ++xx) {
 		DrawDigit(dst, x + xx, y, *s - ' ', bYUY2);
 	}
 }
+
+// Wraps text line if needed, and crops it so it doesn't overflow the image area
+void DrawString(PVideoFrame &dst, int x, int y, const char *s, int bYUY2)
+{
+	int header = 6;      // number of rows for non-frame lines in first column
+	int colChars = 22;   // number characters per diff columns per
+	int charWidth = 10;  // character width in pixels
+	int w = dst->GetRowSize();
+	int h = dst->GetHeight();
+	int rows = h / 20;   // divide by font height
+	int col = y / rows;  // number of raw text columns
+
+	if (col == 0) {
+		_DrawString(dst, x, y, s, bYUY2);      // draw first column normally, as it has headers as well
+	}
+	else {                                     // Special handling for diff column 1+
+		col = (y - header) / (rows - header);  // compute diff column number
+		y += col * header;                     // add whitespace padding to top of diff columns 1-N
+		if (col * colChars * charWidth < w) {  // overflow protection for drawing
+			_DrawString(dst, col * colChars, y % rows, s, bYUY2);
+		}
+	}
+}