Multiple lines w/ text.

[wyrd]

Is there any way to display text with multiple lines? I tried the typical \n for newline, but it doesn't work.

Thanks in advance.

[ppcStudios]

Not inherently to GapiDraw. You'll need to break the text yourself programmatically and place each line accordingly.

[Guest]

Ah, alright. Thanks.

[wyrd]

Bah *logs in*

[mlepage]

Give me a day, I have to write this code too so I'll post it here when I get it done.

[mlepage]

I wrote this and it seems to do the trick.

It uses std::string of _TCHAR, so as long as you pass in _T("text") it will work fine.

It breaks the text into words by space, and draws words at a time. If a word doesn't fit on a line, it starts a new line.

A single leading space is removed on new lines, but other spaces are preserved. As long as you only separate words by one space it will look fine.

If a single word cannot fit on a new line, it stops drawing. It also stops drawing when it reaches the bottom of the area.

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typedef std::string<_TCHAR> tstring; void drawText(     CGapiSurface& surface,     CGapiBitmapFont& font,     const RECT& kRect,     const tstring& ks) {     if (ks.empty())     {         return;     }     const int knLineHeight = font.GetHeight();     int nBeginPos = 0;     int nEndPos = ks.find(_T(" "));     tstring sWord = ks.substr(0, nEndPos);     DWORD nWordWidth;     int nX = kRect.left;     int nY = kRect.top;     if (kRect.bottom < nY + knLineHeight)     {         // The first line doesn't fit, so abort.         return;     }     while (true)     {         // Get the width of the word.         font.GetStringWidth(sWord.c_str(), &nWordWidth);         if (nX + nWordWidth <= kRect.right)         {             // The word fits on this line so draw it.             surface.DrawText(                 nX,                 nY,                 sWord.c_str(),                 &font,                 0,                 NULL,                 0,                 NULL);             // Advance the position.             nX += nWordWidth;             if (nEndPos == tstring::npos)             {                 // We have drawn all the words.                 break;             }             else             {                 // Advance to the next word.                 nBeginPos = nEndPos;                 nEndPos = ks.find(_T(" "), nEndPos + 1);                 sWord = ks.substr(nBeginPos, nEndPos - nBeginPos);             }         }         else         {             // The word doesn't fit on this line.             if (nX == kRect.left)             {                 // This is already a new line, so abort.                 break;             }             else             {                 // Make a new line.                 nY += knLineHeight;                 if (kRect.bottom < nY + knLineHeight)                 {                     // The new line doesn't fit, so abort.                     break;                 }                 // Prepare the new line by removing the leading space.                 nX = kRect.left;                 sWord = sWord.erase(sWord.begin());             }         }     } }

92 lines; 26 keywds; 5 nums; 161 ops; 2 strs; 11 coms    Syntactic Coloring v0.4 - Dan East

[wyrd]

Nice. My implementation was just going to be something simple; search for \n and then move y coords down to the next line.

[mlepage]

Just noticed that typedef should be

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1	typedef std::basic_string<_TCHAR> tstring;
	1 lines; 1 keywds; 0 nums; 5 ops; 0 strs; 0 coms    Syntactic Coloring v0.4 - Dan East

[Layre5150]

How about this:

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bool guiTextbox::drawText( CGapiSurface* pSurface ,                            CGapiBitmapFont* pFont ,                            long lx ,                            long ly ,                            TCHAR* pszString,                            dword dwFlags,                            bool bMultiline ) {                 // Hardcoded for this example     long lFontHeight    = 7;     long lLineSpacing   = 4;     // Get the first line - reading up to the carrage return     TCHAR* pszTok       = NULL;     // If the caller is requesting multiline functionality, then do so using strtok to     // separate the lines using the carrage return     if( bMultiline )     {         pszTok = _tcstok( pszString, _T("\n") );         // While there is a valid string....         while( pszTok )         {             // Draw the text unto the surface.             if( pSurface->DrawText( lx, ly, pszTok, pFont, dwFlags, NULL, 0UL, NULL ) != S_OK )                 return false;             // Increment to the next line             ly += (lFontHeight + lLineSpacing);             // Use the strtok function to obtain the next line             pszTok = _tcstok( NULL, _T("\n")                  );         }     }     else     {         // Otherwise, just draw the string normally.         if( pSurface->DrawText( lx, ly, pszString, pFont, dwFlags, NULL, 0UL, NULL ) != S_OK )             return false;     }     return true; }

46 lines; 17 keywds; 4 nums; 85 ops; 2 strs; 9 coms    Syntactic Coloring v0.4 - Dan East

This takes a bunch of text and for each 0x13 (\n) carriage return it will move to the next line and blit it. It's important to note that the text's X and Y coordinate have already been formatted to handle the various alignment the text can have.

You also may notice that there is no checking to see if the line fits or not and nor is it really needed. This is because if the text does not fit within the boxed area, then it will be chopped off (or simply not rendered). Seeing this, the person who made the text would have to go back and fix up the text (or increase the area where the text goes into) since we would never accept a final product that had missing text within a check box.

Anyways, this is very simple and it works when you add carriage returns to your text. Also note, that the argument 'bMultiline' - if its false, then it will all be blitted on a single line.

[Layre5150]

I should also add that the code above is meant for a static window, one that is not dynamicially resizable. If that is your aim, then you would have to check word for word and handle all the re-formatting within the function.

[ppcStudios]

I should also add that the code above is meant for a static window, one that is not dynamicially resizable. If that is your aim, then you would have to check word for word and handle all the re-formatting within the function.

That's pretty much the method I use in Warlords II for string handling, but I use a pipe ( | ) delimiter instead of looking for embedded control characters. An ascii delimiter makes it easier for the user (and me!) to modify the text to suit their needs - a godsend when you want to localize to a different language. This allows me to put several segments of text on a single line in an ascii text file.

I haven't tried Marc's method of on-the-fly formatting yet. I think it is a fantastic method if you have a scrollable text box like in RPGs.

[fzammetti]

I use the tilde (~) character as my delimiter. I find that's even less useful than the pipe character in actual text

Don't really know why I felt the need to tell anyone this...

[mlepage]

My method works fine for laying out text, but for scrolling, you might want more beef in your data structures. For example, you might want to use a method similar to mine to lay out the text into lines before hand. You could do this by copying the text into a line-oriented data structure, but an even better way is to just make note of where the newlines are in a markup data structure.

Glad to be of help.

[Layre5150]

One thing to be considered is not to "overload" your function with functionality for every eventuality. If your goal is to have a control that handles window resizing then it will need to handle text re-formatting.

However, if the goal is to have a textbox that blits single/multi lines of text with scrolling capabilities then all that is required is just that.

The code that I added could be fixed to scroll with only the smallest amount of changes.

However, having code that meets every condition yet not every condition ends up being met, then it's just the same as not having the code in the first place.

All in all, you want to have code that's robust but you don't want to over-do it.

[mlepage]

What you say is mostly true.

Your code still tokenizes every line for every drawing when it need not do so. It also relies on newlines embedded in the text.

Another way is to tokenize once (using newlines in the file, or a width, or whatever) and store those as character indices, not newline characters. Then, when drawing, you need not recompute the indices, but merely draw the substrings from one index to the next as separate lines.

This is not really more complicated than what you have. And that approach lends itself well to resizing, because you need not alter your text, just the indices of where new lines are.

The function I wrote above will not scroll, and it isn't efficient because it also does computation for every draw that it need only do once. But it's sufficient for drawing text into a rectangle without manually predetermining where all the newlines should be. That's ideal during development, even if for release you change it to a static layout by figuring out where to place new lines.

The nice thing about these forums is that readers have so many different solutions to choose from. It never hurts to see different approaches. Also, they are commented so they make a good starting point even if you want to alter them into something different.