llfontgl.cpp

Go to the documentation of this file.

#include "linden_common.h"

#include <boost/tokenizer.hpp>

#include "llfont.h"
#include "llfontgl.h"
#include "llgl.h"
#include "llglimmediate.h"
#include "v4color.h"
#include "llstl.h"

const S32 BOLD_OFFSET = 1;

// static class members
F32 LLFontGL::sVertDPI = 96.f;
F32 LLFontGL::sHorizDPI = 96.f;
F32 LLFontGL::sScaleX = 1.f;
F32 LLFontGL::sScaleY = 1.f;
BOOL LLFontGL::sDisplayFont = TRUE ;
LLString LLFontGL::sAppDir;

LLFontGL* LLFontGL::sMonospace = NULL;
LLFontGL* LLFontGL::sSansSerifSmall = NULL;
LLFontGL* LLFontGL::sSansSerif = NULL;
LLFontGL* LLFontGL::sSansSerifBig = NULL;
LLFontGL* LLFontGL::sSansSerifHuge = NULL;
LLFontGL* LLFontGL::sSansSerifBold = NULL;
LLFontList*     LLFontGL::sMonospaceFallback = NULL;
LLFontList*     LLFontGL::sSSFallback = NULL;
LLFontList*     LLFontGL::sSSSmallFallback = NULL;
LLFontList*     LLFontGL::sSSBigFallback = NULL;
LLFontList*     LLFontGL::sSSHugeFallback = NULL;
LLFontList*     LLFontGL::sSSBoldFallback = NULL;
LLColor4 LLFontGL::sShadowColor(0.f, 0.f, 0.f, 1.f);

LLCoordFont LLFontGL::sCurOrigin;
std::vector<LLCoordFont> LLFontGL::sOriginStack;

LLFontGL*& gExtCharFont = LLFontGL::sSansSerif;

const F32 EXT_X_BEARING = 1.f;
const F32 EXT_Y_BEARING = 0.f;
const F32 EXT_KERNING = 1.f;
const F32 PIXEL_BORDER_THRESHOLD = 0.0001f;
const F32 PIXEL_CORRECTION_DISTANCE = 0.01f;

const F32 PAD_AMT = 0.5f;
const F32 DROP_SHADOW_SOFT_STRENGTH = 0.3f;

F32 llfont_round_x(F32 x)
{
        //return llfloor((x-LLFontGL::sCurOrigin.mX)/LLFontGL::sScaleX+0.5f)*LLFontGL::sScaleX+LLFontGL::sCurOrigin.mX;
        //return llfloor(x/LLFontGL::sScaleX+0.5f)*LLFontGL::sScaleY;
        return x;
}

F32 llfont_round_y(F32 y)
{
        //return llfloor((y-LLFontGL::sCurOrigin.mY)/LLFontGL::sScaleY+0.5f)*LLFontGL::sScaleY+LLFontGL::sCurOrigin.mY;
        //return llfloor(y+0.5f);
        return y;
}

// static
U8 LLFontGL::getStyleFromString(const LLString &style)
{
        S32 ret = 0;
        if (style.find("NORMAL") != style.npos)
        {
                ret |= NORMAL;
        }
        if (style.find("BOLD") != style.npos)
        {
                ret |= BOLD;
        }
        if (style.find("ITALIC") != style.npos)
        {
                ret |= ITALIC;
        }
        if (style.find("UNDERLINE") != style.npos)
        {
                ret |= UNDERLINE;
        }
        if (style.find("SHADOW") != style.npos)
        {
                ret |= DROP_SHADOW;
        }
        if (style.find("SOFT_SHADOW") != style.npos)
        {
                ret |= DROP_SHADOW_SOFT;
        }
        return ret;
}

LLFontGL::LLFontGL()
        : LLFont()
{
        init();
        clearEmbeddedChars();
}

LLFontGL::LLFontGL(const LLFontGL &source)
{
        llerrs << "Not implemented!" << llendl;
}

LLFontGL::~LLFontGL()
{
        mImageGLp = NULL;
        mRawImageGLp = NULL;
        clearEmbeddedChars();
}

void LLFontGL::init()
{
        if (mImageGLp.isNull())
        {
                mImageGLp = new LLImageGL(FALSE);
                //RN: use nearest mipmap filtering to obviate the need to do pixel-accurate positioning
                mImageGLp->bind();
                // we allow bilinear filtering to get sub-pixel positioning for drop shadows
                //mImageGLp->setMipFilterNearest(TRUE, TRUE);
        }
        if (mRawImageGLp.isNull())
        {
                mRawImageGLp = new LLImageRaw; // Note LLFontGL owns the image, not LLFont.
        }
        setRawImage( mRawImageGLp );  
}

void LLFontGL::reset()
{
        init();
        resetBitmap();
}

// static 
LLString LLFontGL::getFontPathSystem()
{
        LLString system_path;

        // Try to figure out where the system's font files are stored.
        char *system_root = NULL;
#if LL_WINDOWS
        system_root = getenv("SystemRoot");     /* Flawfinder: ignore */
        if (!system_root)
        {
                llwarns << "SystemRoot not found, attempting to load fonts from default path." << llendl;
        }
#endif

        if (system_root)
        {
                system_path = llformat("%s/fonts/", system_root);
        }
        else
        {
#if LL_WINDOWS
                // HACK for windows 98/Me
                system_path = "/WINDOWS/FONTS/";
#elif LL_DARWIN
                // HACK for Mac OS X
                system_path = "/System/Library/Fonts/";
#endif
        }
        return system_path;
}


// static 
LLString LLFontGL::getFontPathLocal()
{
        LLString local_path;

        // Backup files if we can't load from system fonts directory.
        // We could store this in an end-user writable directory to allow
        // end users to switch fonts.
        if (LLFontGL::sAppDir.length())
        {
                // use specified application dir to look for fonts
                local_path = LLFontGL::sAppDir + "/fonts/";
        }
        else
        {
                // assume working directory is executable directory
                local_path = "./fonts/";
        }
        return local_path;
}

//static
bool LLFontGL::loadFaceFallback(LLFontList *fontlistp, const LLString& fontname, const F32 point_size)
{
        LLString local_path = getFontPathLocal();
        LLString sys_path = getFontPathSystem();
        
        // The fontname string may contain multiple font file names separated by semicolons.
        // Break it apart and try loading each one, in order.
        typedef boost::tokenizer<boost::char_separator<char> > tokenizer;
        boost::char_separator<char> sep(";");
        tokenizer tokens(fontname, sep);
        tokenizer::iterator token_iter;

        for(token_iter = tokens.begin(); token_iter != tokens.end(); ++token_iter)
        {
                LLFont *fontp = new LLFont();
                LLString font_path = local_path + *token_iter;
                if (!fontp->loadFace(font_path, point_size, sVertDPI, sHorizDPI, 2, TRUE))
                {
                        font_path = sys_path + *token_iter;
                        if (!fontp->loadFace(font_path, point_size, sVertDPI, sHorizDPI, 2, TRUE))
                        {
                                LL_INFOS_ONCE("ViewerImages") << "Couldn't load font " << *token_iter << LL_ENDL;
                                delete fontp;
                                fontp = NULL;
                        }
                }
                
                if(fontp)
                {
                        fontlistp->addAtEnd(fontp);
                }
        }
        
        // We want to return true if at least one fallback font loaded correctly.
        return (fontlistp->size() > 0);
}

//static
bool LLFontGL::loadFace(LLFontGL *fontp, const LLString& fontname, const F32 point_size, LLFontList *fallback_fontp)
{
        LLString local_path = getFontPathLocal();
        LLString font_path = local_path + fontname;
        if (!fontp->loadFace(font_path, point_size, sVertDPI, sHorizDPI, 2, FALSE))
        {
                LLString sys_path = getFontPathSystem();
                font_path = sys_path + fontname;
                if (!fontp->loadFace(font_path, point_size, sVertDPI, sHorizDPI, 2, FALSE))
                {
                        LL_WARNS("ViewerImages") << "Couldn't load font " << fontname << LL_ENDL;
                        return false;
                }
        }

        fontp->setFallbackFont(fallback_fontp);
        return true;
}


// static
BOOL LLFontGL::initDefaultFonts(F32 screen_dpi, F32 x_scale, F32 y_scale,
                                const LLString& monospace_file, F32 monospace_size,
                                const LLString& sansserif_file,
                                const LLString& sanserif_fallback_file, F32 ss_fallback_scale,
                                F32 small_size, F32 medium_size, F32 big_size, F32 huge_size,
                                const LLString& sansserif_bold_file, F32 bold_size,
                                const LLString& app_dir)
{
        BOOL failed = FALSE;
        sVertDPI = (F32)llfloor(screen_dpi * y_scale);
        sHorizDPI = (F32)llfloor(screen_dpi * x_scale);
        sScaleX = x_scale;
        sScaleY = y_scale;
        sAppDir = app_dir;

        //
        // Monospace font
        //

        if (!sMonospace)
        {
                sMonospace = new LLFontGL();
        }
        else
        {
                sMonospace->reset();
        }

        if (sMonospaceFallback)
        {
                delete sMonospaceFallback;
        }
        sMonospaceFallback = new LLFontList();
        if (!loadFaceFallback(
                        sMonospaceFallback,
                        sanserif_fallback_file,
                        monospace_size * ss_fallback_scale))
        {
                delete sMonospaceFallback;
                sMonospaceFallback = NULL;
        }

        failed |= !loadFace(sMonospace, monospace_file, monospace_size, sMonospaceFallback);

        //
        // Sans-serif fonts
        //
        if(!sSansSerifHuge)
        {
                sSansSerifHuge = new LLFontGL();
        }
        else
        {
                sSansSerifHuge->reset();
        }

        if (sSSHugeFallback)
        {
                delete sSSHugeFallback;
        }
        sSSHugeFallback = new LLFontList();
        if (!loadFaceFallback(
                        sSSHugeFallback,
                        sanserif_fallback_file,
                        huge_size*ss_fallback_scale))
        {
                delete sSSHugeFallback;
                sSSHugeFallback = NULL;
        }

        failed |= !loadFace(sSansSerifHuge, sansserif_file, huge_size, sSSHugeFallback);


        if(!sSansSerifBig)
        {
                sSansSerifBig = new LLFontGL();
        }
        else
        {
                sSansSerifBig->reset();
        }

        if (sSSBigFallback)
        {
                delete sSSBigFallback;
        }
        sSSBigFallback = new LLFontList();
        if (!loadFaceFallback(
                        sSSBigFallback,
                        sanserif_fallback_file,
                        big_size*ss_fallback_scale))
        {
                delete sSSBigFallback;
                sSSBigFallback = NULL;
        }

        failed |= !loadFace(sSansSerifBig, sansserif_file, big_size, sSSBigFallback);


        if(!sSansSerif)
        {
                sSansSerif = new LLFontGL();
        }
        else
        {
                sSansSerif->reset();
        }

        if (sSSFallback)
        {
                delete sSSFallback;
        }
        sSSFallback = new LLFontList();
        if (!loadFaceFallback(
                        sSSFallback,
                        sanserif_fallback_file,
                        medium_size*ss_fallback_scale))
        {
                delete sSSFallback;
                sSSFallback = NULL;
        }
        failed |= !loadFace(sSansSerif, sansserif_file, medium_size, sSSFallback);


        if(!sSansSerifSmall)
        {
                sSansSerifSmall = new LLFontGL();
        }
        else
        {
                sSansSerifSmall->reset();
        }

        if(sSSSmallFallback)
        {
                delete sSSSmallFallback;
        }
        sSSSmallFallback = new LLFontList();
        if (!loadFaceFallback(
                        sSSSmallFallback,
                        sanserif_fallback_file,
                        small_size*ss_fallback_scale))
        {
                delete sSSSmallFallback;
                sSSSmallFallback = NULL;
        }
        failed |= !loadFace(sSansSerifSmall, sansserif_file, small_size, sSSSmallFallback);


        //
        // Sans-serif bold
        //
        if(!sSansSerifBold)
        {
                sSansSerifBold = new LLFontGL();
        }
        else
        {
                sSansSerifBold->reset();
        }

        if (sSSBoldFallback)
        {
                delete sSSBoldFallback;
        }
        sSSBoldFallback = new LLFontList();
        if (!loadFaceFallback(
                        sSSBoldFallback,
                        sanserif_fallback_file,
                        medium_size*ss_fallback_scale))
        {
                delete sSSBoldFallback;
                sSSBoldFallback = NULL;
        }
        failed |= !loadFace(sSansSerifBold, sansserif_bold_file, medium_size, sSSBoldFallback);

        return !failed;
}



// static
void LLFontGL::destroyDefaultFonts()
{
        delete sMonospace;
        sMonospace = NULL;

        delete sSansSerifHuge;
        sSansSerifHuge = NULL;

        delete sSansSerifBig;
        sSansSerifBig = NULL;

        delete sSansSerif;
        sSansSerif = NULL;

        delete sSansSerifSmall;
        sSansSerifSmall = NULL;

        delete sSansSerifBold;
        sSansSerifBold = NULL;

        delete sMonospaceFallback;
        sMonospaceFallback = NULL;

        delete sSSHugeFallback;
        sSSHugeFallback = NULL;

        delete sSSBigFallback;
        sSSBigFallback = NULL;

        delete sSSFallback;
        sSSFallback = NULL;

        delete sSSSmallFallback;
        sSSSmallFallback = NULL;

        delete sSSBoldFallback;
        sSSBoldFallback = NULL;
}

//static 
void LLFontGL::destroyGL()
{
        if (!sMonospace)
        {
                // Already all destroyed.
                return;
        }
        sMonospace->mImageGLp->destroyGLTexture();
        sSansSerifHuge->mImageGLp->destroyGLTexture();
        sSansSerifSmall->mImageGLp->destroyGLTexture();
        sSansSerif->mImageGLp->destroyGLTexture();
        sSansSerifBig->mImageGLp->destroyGLTexture();
        sSansSerifBold->mImageGLp->destroyGLTexture();
}



LLFontGL &LLFontGL::operator=(const LLFontGL &source)
{
        llerrs << "Not implemented" << llendl;
        return *this;
}

BOOL LLFontGL::loadFace(const std::string& filename,
                                                const F32 point_size, const F32 vert_dpi, const F32 horz_dpi,
                                                const S32 components, BOOL is_fallback)
{
        if (!LLFont::loadFace(filename, point_size, vert_dpi, horz_dpi, components, is_fallback))
        {
                return FALSE;
        }
        mImageGLp->createGLTexture(0, mRawImageGLp);
        mImageGLp->bind();
        mImageGLp->setMipFilterNearest(TRUE, TRUE);
        return TRUE;
}

BOOL LLFontGL::addChar(const llwchar wch)
{
        if (!LLFont::addChar(wch))
        {
                return FALSE;
        }

        stop_glerror();
        mImageGLp->setSubImage(mRawImageGLp, 0, 0, mImageGLp->getWidth(), mImageGLp->getHeight());
        mImageGLp->bind();
        mImageGLp->setMipFilterNearest(TRUE, TRUE);
        stop_glerror();
        return TRUE;
}


S32 LLFontGL::renderUTF8(const LLString &text, const S32 offset, 
                                         const F32 x, const F32 y,
                                         const LLColor4 &color,
                                         const HAlign halign, const VAlign valign,
                                         U8 style,
                                         const S32 max_chars, const S32 max_pixels,
                                         F32* right_x,
                                         BOOL use_ellipses) const
{
        LLWString wstr = utf8str_to_wstring(text);
        return render(wstr, offset, x, y, color, halign, valign, style, max_chars, max_pixels, right_x, use_ellipses);
}

S32 LLFontGL::render(const LLWString &wstr, 
                                         const S32 begin_offset,
                                         const F32 x, const F32 y,
                                         const LLColor4 &color,
                                         const HAlign halign, const VAlign valign,
                                         U8 style,
                                         const S32 max_chars, S32 max_pixels,
                                         F32* right_x,
                                         BOOL use_embedded,
                                         BOOL use_ellipses) const
{
        if(!sDisplayFont) //do not display texts
        {
                return wstr.length() ;
        }

        LLGLEnable tex(GL_TEXTURE_2D);

        if (wstr.empty())
        {
                return 0;
        } 

        S32 scaled_max_pixels = max_pixels == S32_MAX ? S32_MAX : llceil((F32)max_pixels * sScaleX);

        // HACK for better bolding
        if (style & BOLD)
        {
                if (this == LLFontGL::sSansSerif)
                {
                        return LLFontGL::sSansSerifBold->render(
                                wstr, begin_offset,
                                x, y,
                                color,
                                halign, valign, 
                                (style & ~BOLD),
                                max_chars, max_pixels,
                                right_x, use_embedded);
                }
        }

        F32 drop_shadow_strength = 0.f;
        if (style & (DROP_SHADOW | DROP_SHADOW_SOFT))
        {
                F32 luminance;
                color.calcHSL(NULL, NULL, &luminance);
                drop_shadow_strength = clamp_rescale(luminance, 0.35f, 0.6f, 0.f, 1.f);
                if (luminance < 0.35f)
                {
                        style = style & ~(DROP_SHADOW | DROP_SHADOW_SOFT);
                }
        }

        gGL.pushMatrix();
        glLoadIdentity();
        gGL.translatef(floorf(sCurOrigin.mX*sScaleX), floorf(sCurOrigin.mY*sScaleY), sCurOrigin.mZ);
        //glScalef(sScaleX, sScaleY, 1.0f);
        
        // avoid half pixels
        // RN: if we're going to this trouble, might as well snap to nearest pixel all the time
        // but the plan is to get rid of this so that fonts "just work"
        //F32 half_pixel_distance = llabs(fmodf(sCurOrigin.mX * sScaleX, 1.f) - 0.5f);
        //if (half_pixel_distance < PIXEL_BORDER_THRESHOLD)
        //{
                gGL.translatef(PIXEL_CORRECTION_DISTANCE*sScaleX, 0.f, 0.f);
        //}

        // this code would just snap to pixel grid, although it seems to introduce more jitter
        //F32 pixel_offset_x = llround(sCurOrigin.mX * sScaleX) - (sCurOrigin.mX * sScaleX);
        //F32 pixel_offset_y = llround(sCurOrigin.mY * sScaleY) - (sCurOrigin.mY * sScaleY);
        //gGL.translatef(-pixel_offset_x, -pixel_offset_y, 0.f);

        // scale back to native pixel size
        //glScalef(1.f / sScaleX, 1.f / sScaleY, 1.f);
        //glScaled(1.0 / (F64) sScaleX, 1.0 / (F64) sScaleY, 1.0f);
        LLFastTimer t(LLFastTimer::FTM_RENDER_FONTS);

        gGL.color4fv( color.mV );

        S32 chars_drawn = 0;
        S32 i;
        S32 length;

        if (-1 == max_chars)
        {
                length = (S32)wstr.length() - begin_offset;
        }
        else
        {
                length = llmin((S32)wstr.length() - begin_offset, max_chars );
        }

        F32 cur_x, cur_y, cur_render_x, cur_render_y;

        // Bind the font texture
        
        mImageGLp->bind(0);
        
        gGL.blendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); // Not guaranteed to be set correctly
        
        cur_x = ((F32)x * sScaleX);
        cur_y = ((F32)y * sScaleY);

        // Offset y by vertical alignment.
        switch (valign)
        {
        case TOP:
                cur_y -= mAscender;
                break;
        case BOTTOM:
                cur_y += mDescender;
                break;
        case VCENTER:
                cur_y -= ((mAscender - mDescender)/2.f);
                break;
        case BASELINE:
                // Baseline, do nothing.
                break;
        default:
                break;
        }

        switch (halign)
        {
        case LEFT:
                break;
        case RIGHT:
                cur_x -= llmin(scaled_max_pixels, llround(getWidthF32(wstr.c_str(), 0, length) * sScaleX));
                break;
        case HCENTER:
            cur_x -= llmin(scaled_max_pixels, llround(getWidthF32(wstr.c_str(), 0, length) * sScaleX)) / 2;
                break;
        default:
                break;
        }

        // Round properly.
        //cur_render_y = (F32)llfloor(cur_y/sScaleY + 0.5f)*sScaleY;
        //cur_render_x = (F32)llfloor(cur_x/sScaleX + 0.5f)*sScaleX;
        
        cur_render_y = cur_y;
        cur_render_x = cur_x;

        F32 start_x = cur_x;

        F32 inv_width = 1.f / mImageGLp->getWidth();
        F32 inv_height = 1.f / mImageGLp->getHeight();

        const S32 LAST_CHARACTER = LLFont::LAST_CHAR_FULL;


        BOOL draw_ellipses = FALSE;
        if (use_ellipses && halign == LEFT)
        {
                // check for too long of a string
                if (getWidthF32(wstr.c_str(), 0, max_chars) * sScaleX > scaled_max_pixels)
                {
                        // use four dots for ellipsis width to generate padding
                        const LLWString dots(utf8str_to_wstring(LLString("....")));
                        scaled_max_pixels = llmax(0, scaled_max_pixels - llround(getWidthF32(dots.c_str())));
                        draw_ellipses = TRUE;
                }
        }


        for (i = begin_offset; i < begin_offset + length; i++)
        {
                llwchar wch = wstr[i];

                // Handle embedded characters first, if they're enabled.
                // Embedded characters are a hack for notecards
                const embedded_data_t* ext_data = use_embedded ? getEmbeddedCharData(wch) : NULL;
                if (ext_data)
                {
                        LLImageGL* ext_image = ext_data->mImage;
                        const LLWString& label = ext_data->mLabel;

                        F32 ext_height = (F32)ext_image->getHeight() * sScaleY;

                        F32 ext_width = (F32)ext_image->getWidth() * sScaleX;
                        F32 ext_advance = (EXT_X_BEARING * sScaleX) + ext_width;

                        if (!label.empty())
                        {
                                ext_advance += (EXT_X_BEARING + gExtCharFont->getWidthF32( label.c_str() )) * sScaleX;
                        }

                        if (start_x + scaled_max_pixels < cur_x + ext_advance)
                        {
                                // Not enough room for this character.
                                break;
                        }

                        ext_image->bind();
                        const F32 ext_x = cur_render_x + (EXT_X_BEARING * sScaleX);
                        const F32 ext_y = cur_render_y + (EXT_Y_BEARING * sScaleY + mAscender - mLineHeight);

                        LLRectf uv_rect(0.f, 1.f, 1.f, 0.f);
                        LLRectf screen_rect(ext_x, ext_y + ext_height, ext_x + ext_width, ext_y);
                        drawGlyph(screen_rect, uv_rect, LLColor4::white, style, drop_shadow_strength);

                        if (!label.empty())
                        {
                                gGL.pushMatrix();
                                //glLoadIdentity();
                                //gGL.translatef(sCurOrigin.mX, sCurOrigin.mY, 0.0f);
                                //glScalef(sScaleX, sScaleY, 1.f);
                                gExtCharFont->render(label, 0,
                                                                         /*llfloor*/((ext_x + (F32)ext_image->getWidth() + EXT_X_BEARING) / sScaleX), 
                                                                         /*llfloor*/(cur_y / sScaleY),
                                                                         color,
                                                                         halign, BASELINE, NORMAL, S32_MAX, S32_MAX, NULL,
                                                                         TRUE );
                                gGL.popMatrix();
                        }

                        gGL.color4fv(color.mV);

                        chars_drawn++;
                        cur_x += ext_advance;
                        if (((i + 1) < length) && wstr[i+1])
                        {
                                cur_x += EXT_KERNING * sScaleX;
                        }
                        cur_render_x = cur_x;

                        // Bind the font texture
                        mImageGLp->bind();
                }
                else
                {
                        if (!hasGlyph(wch))
                        {
                                (const_cast<LLFontGL*>(this))->addChar(wch);
                        }

                        const LLFontGlyphInfo* fgi= getGlyphInfo(wch);
                        if (!fgi)
                        {
                                llerrs << "Missing Glyph Info" << llendl;
                                break;
                        }
                        if ((start_x + scaled_max_pixels) < (cur_x + fgi->mXBearing + fgi->mWidth))
                        {
                                // Not enough room for this character.
                                break;
                        }

                        // Draw the text at the appropriate location
                        //Specify vertices and texture coordinates
                        LLRectf uv_rect((fgi->mXBitmapOffset - PAD_AMT) * inv_width,
                                                        (fgi->mYBitmapOffset + fgi->mHeight + PAD_AMT) * inv_height,
                                                        (fgi->mXBitmapOffset + fgi->mWidth + PAD_AMT) * inv_width,
                                                        (fgi->mYBitmapOffset - PAD_AMT) * inv_height);
                        LLRectf screen_rect(cur_render_x + (F32)fgi->mXBearing - PAD_AMT,
                                                                cur_render_y + (F32)fgi->mYBearing + PAD_AMT,
                                                                cur_render_x + (F32)fgi->mXBearing + (F32)fgi->mWidth + PAD_AMT,
                                                                cur_render_y + (F32)fgi->mYBearing - (F32)fgi->mHeight - PAD_AMT);

                        drawGlyph(screen_rect, uv_rect, color, style, drop_shadow_strength);

                        chars_drawn++;
                        cur_x += fgi->mXAdvance;
                        cur_y += fgi->mYAdvance;

                        llwchar next_char = wstr[i+1];
                        if (next_char && (next_char < LAST_CHARACTER))
                        {
                                // Kern this puppy.
                                if (!hasGlyph(next_char))
                                {
                                        (const_cast<LLFontGL*>(this))->addChar(next_char);
                                }
                                cur_x += getXKerning(wch, next_char);
                        }

                        // Round after kerning.
                        // Must do this to cur_x, not just to cur_render_x, otherwise you
                        // will squish sub-pixel kerned characters too close together.
                        // For example, "CCCCC" looks bad.
                        cur_x = (F32)llfloor(cur_x + 0.5f);
                        //cur_y = (F32)llfloor(cur_y + 0.5f);

                        cur_render_x = cur_x;
                        cur_render_y = cur_y;
                }
        }

        if (right_x)
        {
                *right_x = cur_x / sScaleX;
        }

        if (style & UNDERLINE)
        {
                LLGLSNoTexture no_texture;
                gGL.begin(LLVertexBuffer::LINES);
                gGL.vertex2f(start_x, cur_y - (mDescender));
                gGL.vertex2f(cur_x, cur_y - (mDescender));
                gGL.end();
        }

        // *FIX: get this working in all alignment cases, etc.
        if (draw_ellipses)
        {
                // recursively render ellipses at end of string
                // we've already reserved enough room
                gGL.pushMatrix();
                //glLoadIdentity();
                //gGL.translatef(sCurOrigin.mX, sCurOrigin.mY, 0.0f);
                //glScalef(sScaleX, sScaleY, 1.f);
                renderUTF8("...", 
                                0,
                                cur_x / sScaleX, (F32)y,
                                color,
                                LEFT, valign,
                                style,
                                S32_MAX, max_pixels,
                                right_x,
                                FALSE); 
                gGL.popMatrix();
        }

        gGL.popMatrix();

        return chars_drawn;
}

 
LLImageGL *LLFontGL::getImageGL() const
{
        return mImageGLp;
}

S32 LLFontGL::getWidth(const LLString& utf8text) const
{
        LLWString wtext = utf8str_to_wstring(utf8text);
        return getWidth(wtext.c_str(), 0, S32_MAX);
}

S32 LLFontGL::getWidth(const llwchar* wchars) const
{
        return getWidth(wchars, 0, S32_MAX);
}

S32 LLFontGL::getWidth(const LLString& utf8text, const S32 begin_offset, const S32 max_chars) const
{
        LLWString wtext = utf8str_to_wstring(utf8text);
        return getWidth(wtext.c_str(), begin_offset, max_chars);
}

S32 LLFontGL::getWidth(const llwchar* wchars, const S32 begin_offset, const S32 max_chars, BOOL use_embedded) const
{
        F32 width = getWidthF32(wchars, begin_offset, max_chars, use_embedded);
        return llround(width);
}

F32 LLFontGL::getWidthF32(const LLString& utf8text) const
{
        LLWString wtext = utf8str_to_wstring(utf8text);
        return getWidthF32(wtext.c_str(), 0, S32_MAX);
}

F32 LLFontGL::getWidthF32(const llwchar* wchars) const
{
        return getWidthF32(wchars, 0, S32_MAX);
}

F32 LLFontGL::getWidthF32(const LLString& utf8text, const S32 begin_offset, const S32 max_chars ) const
{
        LLWString wtext = utf8str_to_wstring(utf8text);
        return getWidthF32(wtext.c_str(), begin_offset, max_chars);
}

F32 LLFontGL::getWidthF32(const llwchar* wchars, const S32 begin_offset, const S32 max_chars, BOOL use_embedded) const
{
        const S32 LAST_CHARACTER = LLFont::LAST_CHAR_FULL;

        F32 cur_x = 0;
        const S32 max_index = begin_offset + max_chars;
        for (S32 i = begin_offset; i < max_index; i++)
        {
                const llwchar wch = wchars[i];
                if (wch == 0)
                {
                        break; // done
                }
                const embedded_data_t* ext_data = use_embedded ? getEmbeddedCharData(wch) : NULL;
                if (ext_data)
                {
                        // Handle crappy embedded hack
                        cur_x += getEmbeddedCharAdvance(ext_data);

                        if( ((i+1) < max_chars) && (i+1 < max_index))
                        {
                                cur_x += EXT_KERNING * sScaleX;
                        }
                }
                else
                {
                        cur_x += getXAdvance(wch);
                        llwchar next_char = wchars[i+1];

                        if (((i + 1) < max_chars) 
                                && next_char 
                                && (next_char < LAST_CHARACTER))
                        {
                                // Kern this puppy.
                                cur_x += getXKerning(wch, next_char);
                        }
                }
                // Round after kerning.
                cur_x = (F32)llfloor(cur_x + 0.5f);
        }

        return cur_x / sScaleX;
}



// Returns the max number of complete characters from text (up to max_chars) that can be drawn in max_pixels
S32 LLFontGL::maxDrawableChars(const llwchar* wchars, F32 max_pixels, S32 max_chars,
                                                           BOOL end_on_word_boundary, const BOOL use_embedded,
                                                           F32* drawn_pixels) const
{
        if (!wchars || !wchars[0] || max_chars == 0)
        {
                return 0;
        }
        
        llassert(max_pixels >= 0.f);
        llassert(max_chars >= 0);
        
        BOOL clip = FALSE;
        F32 cur_x = 0;
        F32 drawn_x = 0;

        S32 start_of_last_word = 0;
        BOOL in_word = FALSE;

        F32 scaled_max_pixels = (F32)llceil(max_pixels * sScaleX);

        S32 i;
        for (i=0; (i < max_chars); i++)
        {
                llwchar wch = wchars[i];

                if(wch == 0)
                {
                        // Null terminator.  We're done.
                        break;
                }
                        
                const embedded_data_t* ext_data = use_embedded ? getEmbeddedCharData(wch) : NULL;
                if (ext_data)
                {
                        if (in_word)
                        {
                                in_word = FALSE;
                        }
                        else
                        {
                                start_of_last_word = i;
                        }
                        cur_x += getEmbeddedCharAdvance(ext_data);
                        
                        if (scaled_max_pixels < cur_x)
                        {
                                clip = TRUE;
                                break;
                        }
                        
                        if (((i+1) < max_chars) && wchars[i+1])
                        {
                                cur_x += EXT_KERNING * sScaleX;
                        }

                        if( scaled_max_pixels < cur_x )
                        {
                                clip = TRUE;
                                break;
                        }
                }
                else
                {
                        if (in_word)
                        {
                                if (iswspace(wch))
                                {
                                        in_word = FALSE;
                                }
                        }
                        else
                        {
                                start_of_last_word = i;
                                if (!iswspace(wch))
                                {
                                        in_word = TRUE;
                                }
                        }

                        cur_x += getXAdvance(wch);
                        
                        if (scaled_max_pixels < cur_x)
                        {
                                clip = TRUE;
                                break;
                        }

                        if (((i+1) < max_chars) && wchars[i+1])
                        {
                                // Kern this puppy.
                                cur_x += getXKerning(wch, wchars[i+1]);
                        }
                }
                // Round after kerning.
                cur_x = (F32)llfloor(cur_x + 0.5f);
                drawn_x = cur_x;
        }

        if( clip && end_on_word_boundary && (start_of_last_word != 0) )
        {
                i = start_of_last_word;
        }
        if (drawn_pixels)
        {
                *drawn_pixels = drawn_x;
        }
        return i;
}


S32     LLFontGL::firstDrawableChar(const llwchar* wchars, F32 max_pixels, S32 text_len, S32 start_pos, S32 max_chars) const
{
        if (!wchars || !wchars[0] || max_chars == 0)
        {
                return 0;
        }
        
        F32 total_width = 0.0;
        S32 drawable_chars = 0;

        F32 scaled_max_pixels = max_pixels * sScaleX;

        S32 start = llmin(start_pos, text_len - 1);
        for (S32 i = start; i >= 0; i--)
        {
                llwchar wch = wchars[i];

                const embedded_data_t* ext_data = getEmbeddedCharData(wch);
                if (ext_data)
                {
                        F32 char_width = getEmbeddedCharAdvance(ext_data);

                        if( scaled_max_pixels < (total_width + char_width) )
                        {
                                break;
                        }

                        total_width += char_width;

                        drawable_chars++;
                        if( max_chars >= 0 && drawable_chars >= max_chars )
                        {
                                break;
                        }

                        if ( i > 0 )
                        {
                                total_width += EXT_KERNING * sScaleX;
                        }

                        // Round after kerning.
                        total_width = (F32)llfloor(total_width + 0.5f);
                }
                else
                {
                        F32 char_width = getXAdvance(wch);
                        if( scaled_max_pixels < (total_width + char_width) )
                        {
                                break;
                        }

                        total_width += char_width;

                        drawable_chars++;
                        if( max_chars >= 0 && drawable_chars >= max_chars )
                        {
                                break;
                        }

                        if ( i > 0 )
                        {
                                // Kerning
                                total_width += getXKerning(wchars[i-1], wch);
                        }

                        // Round after kerning.
                        total_width = (F32)llfloor(total_width + 0.5f);
                }
        }

        return text_len - drawable_chars;
}


S32 LLFontGL::charFromPixelOffset(const llwchar* wchars, const S32 begin_offset, F32 target_x, F32 max_pixels, S32 max_chars, BOOL round, BOOL use_embedded) const
{
        if (!wchars || !wchars[0] || max_chars == 0)
        {
                return 0;
        }
        
        F32 cur_x = 0;
        S32 pos = 0;

        target_x *= sScaleX;

        // max_chars is S32_MAX by default, so make sure we don't get overflow
        const S32 max_index = begin_offset + llmin(S32_MAX - begin_offset, max_chars);

        F32 scaled_max_pixels = max_pixels * sScaleX;

        for (S32 i = begin_offset; (i < max_index); i++)
        {
                llwchar wch = wchars[i];
                if (!wch)
                {
                        break; // done
                }
                const embedded_data_t* ext_data = use_embedded ? getEmbeddedCharData(wch) : NULL;
                if (ext_data)
                {
                        F32 ext_advance = getEmbeddedCharAdvance(ext_data);

                        if (round)
                        {
                                // Note: if the mouse is on the left half of the character, the pick is to the character's left
                                // If it's on the right half, the pick is to the right.
                                if (target_x  < cur_x + ext_advance/2)
                                {
                                        break;
                                }
                        }
                        else
                        {
                                if (target_x  < cur_x + ext_advance)
                                {
                                        break;
                                }
                        }

                        if (scaled_max_pixels < cur_x + ext_advance)
                        {
                                break;
                        }

                        pos++;
                        cur_x += ext_advance;

                        if (((i + 1) < max_index)
                                && (wchars[(i + 1)]))
                        {
                                cur_x += EXT_KERNING * sScaleX;
                        }
                        // Round after kerning.
                        cur_x = (F32)llfloor(cur_x + 0.5f);
                }
                else
                {
                        F32 char_width = getXAdvance(wch);

                        if (round)
                        {
                                // Note: if the mouse is on the left half of the character, the pick is to the character's left
                                // If it's on the right half, the pick is to the right.
                                if (target_x  < cur_x + char_width*0.5f)
                                {
                                        break;
                                }
                        }
                        else if (target_x  < cur_x + char_width)
                        {
                                break;
                        }

                        if (scaled_max_pixels < cur_x + char_width)
                        {
                                break;
                        }

                        pos++;
                        cur_x += char_width;

                        if (((i + 1) < max_index)
                                && (wchars[(i + 1)]))
                        {
                                llwchar next_char = wchars[i + 1];
                                // Kern this puppy.
                                cur_x += getXKerning(wch, next_char);
                        }

                        // Round after kerning.
                        cur_x = (F32)llfloor(cur_x + 0.5f);
                }
        }

        return pos;
}


const LLFontGL::embedded_data_t* LLFontGL::getEmbeddedCharData(const llwchar wch) const
{
        // Handle crappy embedded hack
        embedded_map_t::const_iterator iter = mEmbeddedChars.find(wch);
        if (iter != mEmbeddedChars.end())
        {
                return iter->second;
        }
        return NULL;
}


F32 LLFontGL::getEmbeddedCharAdvance(const embedded_data_t* ext_data) const
{
        const LLWString& label = ext_data->mLabel;
        LLImageGL* ext_image = ext_data->mImage;

        F32 ext_width = (F32)ext_image->getWidth();
        if( !label.empty() )
        {
                ext_width += (EXT_X_BEARING + gExtCharFont->getWidthF32(label.c_str())) * sScaleX;
        }

        return (EXT_X_BEARING * sScaleX) + ext_width;
}


void LLFontGL::clearEmbeddedChars()
{
        for_each(mEmbeddedChars.begin(), mEmbeddedChars.end(), DeletePairedPointer());
        mEmbeddedChars.clear();
}

void LLFontGL::addEmbeddedChar( llwchar wc, LLImageGL* image, const LLString& label )
{
        LLWString wlabel = utf8str_to_wstring(label);
        addEmbeddedChar(wc, image, wlabel);
}

void LLFontGL::addEmbeddedChar( llwchar wc, LLImageGL* image, const LLWString& wlabel )
{
        embedded_data_t* ext_data = new embedded_data_t(image, wlabel);
        mEmbeddedChars[wc] = ext_data;
}

void LLFontGL::removeEmbeddedChar( llwchar wc )
{
        embedded_map_t::iterator iter = mEmbeddedChars.find(wc);
        if (iter != mEmbeddedChars.end())
        {
                delete iter->second;
                mEmbeddedChars.erase(wc);
        }
}


void LLFontGL::renderQuad(const LLRectf& screen_rect, const LLRectf& uv_rect, F32 slant_amt) const
{
        gGL.texCoord2f(uv_rect.mRight, uv_rect.mTop);
        gGL.vertex2f(llfont_round_x(screen_rect.mRight), 
                                llfont_round_y(screen_rect.mTop));

        gGL.texCoord2f(uv_rect.mLeft, uv_rect.mTop);
        gGL.vertex2f(llfont_round_x(screen_rect.mLeft), 
                                llfont_round_y(screen_rect.mTop));

        gGL.texCoord2f(uv_rect.mLeft, uv_rect.mBottom);
        gGL.vertex2f(llfont_round_x(screen_rect.mLeft + slant_amt), 
                                llfont_round_y(screen_rect.mBottom));

        gGL.texCoord2f(uv_rect.mRight, uv_rect.mBottom);
        gGL.vertex2f(llfont_round_x(screen_rect.mRight + slant_amt), 
                                llfont_round_y(screen_rect.mBottom));
}

void LLFontGL::drawGlyph(const LLRectf& screen_rect, const LLRectf& uv_rect, const LLColor4& color, U8 style, F32 drop_shadow_strength) const
{
        F32 slant_offset;
        slant_offset = ((style & ITALIC) ? ( -mAscender * 0.2f) : 0.f);

        gGL.begin(LLVertexBuffer::QUADS);
        {
                //FIXME: bold and drop shadow are mutually exclusive only for convenience
                //Allow both when we need them.
                if (style & BOLD)
                {
                        gGL.color4fv(color.mV);
                        for (S32 pass = 0; pass < 2; pass++)
                        {
                                LLRectf screen_rect_offset = screen_rect;

                                screen_rect_offset.translate((F32)(pass * BOLD_OFFSET), 0.f);
                                renderQuad(screen_rect_offset, uv_rect, slant_offset);
                        }
                }
                else if (style & DROP_SHADOW_SOFT)
                {
                        LLColor4 shadow_color = LLFontGL::sShadowColor;
                        shadow_color.mV[VALPHA] = color.mV[VALPHA] * drop_shadow_strength * DROP_SHADOW_SOFT_STRENGTH;
                        gGL.color4fv(shadow_color.mV);
                        for (S32 pass = 0; pass < 5; pass++)
                        {
                                LLRectf screen_rect_offset = screen_rect;

                                switch(pass)
                                {
                                case 0:
                                        screen_rect_offset.translate(-1.f, -1.f);
                                        break;
                                case 1:
                                        screen_rect_offset.translate(1.f, -1.f);
                                        break;
                                case 2:
                                        screen_rect_offset.translate(1.f, 1.f);
                                        break;
                                case 3:
                                        screen_rect_offset.translate(-1.f, 1.f);
                                        break;
                                case 4:
                                        screen_rect_offset.translate(0, -2.f);
                                        break;
                                }
                        
                                renderQuad(screen_rect_offset, uv_rect, slant_offset);
                        }
                        gGL.color4fv(color.mV);
                        renderQuad(screen_rect, uv_rect, slant_offset);
                }
                else if (style & DROP_SHADOW)
                {
                        LLColor4 shadow_color = LLFontGL::sShadowColor;
                        shadow_color.mV[VALPHA] = color.mV[VALPHA] * drop_shadow_strength;
                        gGL.color4fv(shadow_color.mV);
                        LLRectf screen_rect_shadow = screen_rect;
                        screen_rect_shadow.translate(1.f, -1.f);
                        renderQuad(screen_rect_shadow, uv_rect, slant_offset);
                        gGL.color4fv(color.mV);
                        renderQuad(screen_rect, uv_rect, slant_offset);
                }
                else // normal rendering
                {
                        gGL.color4fv(color.mV);
                        renderQuad(screen_rect, uv_rect, slant_offset);
                }

        }
        gGL.end();
}

// static
LLString LLFontGL::nameFromFont(const LLFontGL* fontp)
{
        if (fontp == sSansSerifHuge)
        {
                return LLString("SansSerifHuge");
        }
        else if (fontp == sSansSerifSmall)
        {
                return LLString("SansSerifSmall");
        }
        else if (fontp == sSansSerif)
        {
                return LLString("SansSerif");
        }
        else if (fontp == sSansSerifBig)
        {
                return LLString("SansSerifBig");
        }
        else if (fontp == sSansSerifBold)
        {
                return LLString("SansSerifBold");
        }
        else if (fontp == sMonospace)
        {
                return LLString("Monospace");
        }
        else
        {
                return LLString();
        }
}

// static
LLFontGL* LLFontGL::fontFromName(const LLString& font_name)
{
        LLFontGL* gl_font = NULL;
        if (font_name == "SansSerifHuge")
        {
                gl_font = LLFontGL::sSansSerifHuge;
        }
        else if (font_name == "SansSerifSmall")
        {
                gl_font = LLFontGL::sSansSerifSmall;
        }
        else if (font_name == "SansSerif")
        {
                gl_font = LLFontGL::sSansSerif;
        }
        else if (font_name == "SansSerifBig")
        {
                gl_font = LLFontGL::sSansSerifBig;
        }
        else if (font_name == "SansSerifBold")
        {
                gl_font = LLFontGL::sSansSerifBold;
        }
        else if (font_name == "Monospace")
        {
                gl_font = LLFontGL::sMonospace;
        }
        return gl_font;
}

// static
LLString LLFontGL::nameFromHAlign(LLFontGL::HAlign align)
{
        if (align == LEFT)                      return LLString("left");
        else if (align == RIGHT)        return LLString("right");
        else if (align == HCENTER)      return LLString("center");
        else return LLString();
}

// static
LLFontGL::HAlign LLFontGL::hAlignFromName(const LLString& name)
{
        LLFontGL::HAlign gl_hfont_align = LLFontGL::LEFT;
        if (name == "left")
        {
                gl_hfont_align = LLFontGL::LEFT;
        }
        else if (name == "right")
        {
                gl_hfont_align = LLFontGL::RIGHT;
        }
        else if (name == "center")
        {
                gl_hfont_align = LLFontGL::HCENTER;
        }
        //else leave left
        return gl_hfont_align;
}

// static
LLString LLFontGL::nameFromVAlign(LLFontGL::VAlign align)
{
        if (align == TOP)                       return LLString("top");
        else if (align == VCENTER)      return LLString("center");
        else if (align == BASELINE)     return LLString("baseline");
        else if (align == BOTTOM)       return LLString("bottom");
        else return LLString();
}

// static
LLFontGL::VAlign LLFontGL::vAlignFromName(const LLString& name)
{
        LLFontGL::VAlign gl_vfont_align = LLFontGL::BASELINE;
        if (name == "top")
        {
                gl_vfont_align = LLFontGL::TOP;
        }
        else if (name == "center")
        {
                gl_vfont_align = LLFontGL::VCENTER;
        }
        else if (name == "baseline")
        {
                gl_vfont_align = LLFontGL::BASELINE;
        }
        else if (name == "bottom")
        {
                gl_vfont_align = LLFontGL::BOTTOM;
        }
        //else leave baseline
        return gl_vfont_align;
}

---