llhudtext.cpp

Go to the documentation of this file.

#include "llviewerprecompiledheaders.h"

#include "llhudtext.h"

#include "llagent.h"
#include "llviewercontrol.h"
#include "llchatbar.h"
#include "llcriticaldamp.h"
#include "lldrawable.h"
#include "llfontgl.h"
#include "llglheaders.h"
#include "llhudrender.h"
#include "llimagegl.h"
#include "llui.h"
#include "llviewercamera.h"
#include "llviewerimagelist.h"
#include "llviewerobject.h"
#include "llvovolume.h"
#include "llviewerwindow.h"
#include "viewer.h"
#include "llstatusbar.h"
#include "llmenugl.h"
#include "pipeline.h"
#include <boost/tokenizer.hpp>


const F32 SPRING_STRENGTH = 0.7f;
const F32 RESTORATION_SPRING_TIME_CONSTANT = 0.1f;
const F32 HORIZONTAL_PADDING = 15.f;
const F32 VERTICAL_PADDING = 12.f;
const F32 BUFFER_SIZE = 2.f;
const F32 MIN_EDGE_OVERLAP = 3.f;
F32 HUD_TEXT_MAX_WIDTH = 190.f;
const F32 HUD_TEXT_MAX_WIDTH_NO_BUBBLE = 1000.f;
const F32 RESIZE_TIME = 0.f;
const S32 NUM_OVERLAP_ITERATIONS = 10;
const F32 NEIGHBOR_FORCE_FRACTION = 1.f;
const F32 POSITION_DAMPING_TC = 0.2f;
const F32 MAX_STABLE_CAMERA_VELOCITY = 0.1f;
const F32 LOD_0_SCREEN_COVERAGE = 0.15f;
const F32 LOD_1_SCREEN_COVERAGE = 0.30f;
const F32 LOD_2_SCREEN_COVERAGE = 0.40f;

std::set<LLPointer<LLHUDText> > LLHUDText::sTextObjects;
std::vector<LLPointer<LLHUDText> > LLHUDText::sVisibleTextObjects;
std::vector<LLPointer<LLHUDText> > LLHUDText::sVisibleHUDTextObjects;

bool lltextobject_further_away::operator()(const LLPointer<LLHUDText>& lhs, const LLPointer<LLHUDText>& rhs) const
{
        return (lhs->getDistance() > rhs->getDistance()) ? true : false;
}


LLHUDText::LLHUDText(const U8 type) :
                        LLHUDObject(type),
                        mUseBubble(FALSE),
                        mUsePixelSize(TRUE),
                        mVisibleOffScreen(FALSE),
                        mWidth(0.f),
                        mHeight(0.f),
                        mFontp(LLFontGL::sSansSerifSmall),
                        mBoldFontp(LLFontGL::sSansSerifBold),
                        mMass(1.f),
                        mMaxLines(10),
                        mOffsetY(0),
                        mTextAlignment(ALIGN_TEXT_CENTER),
                        mVertAlignment(ALIGN_VERT_CENTER),
                        mLOD(0),
                        mHidden(FALSE)
{
        mColor = LLColor4(1.f, 1.f, 1.f, 1.f);
        mBackgroundColor = gSavedSettings.getColor4("BackgroundChatColor");
        mDoFade = TRUE;
        mFadeDistance = 8.f;
        mFadeRange = 4.f;
        mZCompare = TRUE;
        mDropShadow = TRUE;
        mOffscreen = FALSE;
        mRadius = 0.1f;
        LLPointer<LLHUDText> ptr(this);
        sTextObjects.insert(ptr);
        //LLDebugVarMessageBox::show("max width", &HUD_TEXT_MAX_WIDTH, 500.f, 1.f);
}

LLHUDText::~LLHUDText()
{
}


void LLHUDText::render()
{
        if (!mOnHUDAttachment)
        {
                LLGLDepthTest gls_depth(GL_TRUE, GL_FALSE);
                renderText(FALSE);
        }
}

void LLHUDText::renderForSelect()
{
        if (!mOnHUDAttachment)
        {
                LLGLDepthTest gls_depth(GL_TRUE, GL_FALSE);
                renderText(TRUE);
        }
}

void LLHUDText::renderText(BOOL for_select)
{
        if (!mVisible || mHidden)
        {
                return;
        }

        // don't pick text that isn't bound to a viewerobject or isn't in a bubble
        if (for_select && 
                (!mSourceObject || mSourceObject->mDrawable.isNull() || !mUseBubble))
        {
                return;
        }
        
        LLGLState gls_tex(GL_TEXTURE_2D, for_select ? FALSE : TRUE);
        LLGLState gls_blend(GL_BLEND, for_select ? FALSE : TRUE);
        LLGLState gls_alpha(GL_ALPHA_TEST, for_select ? FALSE : TRUE);
        
        LLColor4 shadow_color(0.f, 0.f, 0.f, 1.f);
        F32 alpha_factor = 1.f;
        LLColor4 text_color = mColor;
        if (mDoFade)
        {
                if (mLastDistance > mFadeDistance)
                {
                        alpha_factor = llmax(0.f, 1.f - (mLastDistance - mFadeDistance)/mFadeRange);
                        text_color.mV[3] = text_color.mV[3]*alpha_factor;
                }
        }
        if (text_color.mV[3] < 0.01f)
        {
                return;
        }
        shadow_color.mV[3] = text_color.mV[3];

        mOffsetY = lltrunc(mHeight * ((mVertAlignment == ALIGN_VERT_CENTER) ? 0.5f : 1.f));

        // *TODO: cache this image
        LLUUID image_id;
        image_id.set(gViewerArt.getString("rounded_square.tga"));
        LLViewerImage* imagep = gImageList.getImage(image_id, MIPMAP_FALSE, TRUE);

        LLColor4 bg_color = mBackgroundColor;
        bg_color.setAlpha(gSavedSettings.getF32("ChatBubbleOpacity") * alpha_factor);

        const S32 border_height = 16;
        const S32 border_width = 16;

        // *TODO move this into helper function
        F32 border_scale = 1.f;

        if (border_height * 2 > mHeight)
        {
                border_scale = (F32)mHeight / ((F32)border_height * 2.f);
        }
        if (border_width * 2 > mWidth)
        {
                border_scale = llmin(border_scale, (F32)mWidth / ((F32)border_width * 2.f));
        }

        // scale screen size of borders down
        //RN: for now, text on hud objects is never occluded

        LLVector3 x_pixel_vec;
        LLVector3 y_pixel_vec;
        
        if (mOnHUDAttachment)
        {
                x_pixel_vec = LLVector3::y_axis / (F32)gViewerWindow->getWindowWidth();
                y_pixel_vec = LLVector3::z_axis / (F32)gViewerWindow->getWindowHeight();
        }
        else
        {
                gCamera->getPixelVectors(mPositionAgent, y_pixel_vec, x_pixel_vec);
        }

        LLVector2 border_scale_vec((F32)border_width / (F32)imagep->getWidth(), (F32)border_height / (F32)imagep->getHeight());
        LLVector3 width_vec = mWidth * x_pixel_vec;
        LLVector3 height_vec = mHeight * y_pixel_vec;
        LLVector3 scaled_border_width = (F32)llfloor(border_scale * (F32)border_width) * x_pixel_vec;
        LLVector3 scaled_border_height = (F32)llfloor(border_scale * (F32)border_height) * y_pixel_vec;

        mRadius = (width_vec + height_vec).magVec() * 0.5f;

        LLCoordGL screen_pos;
        gCamera->projectPosAgentToScreen(mPositionAgent, screen_pos, FALSE);

        LLVector2 screen_offset;
        if (!mUseBubble)
        {
                screen_offset = mPositionOffset;
        }
        else
        {
                screen_offset = updateScreenPos(mPositionOffset);
        }

        LLVector3 render_position = mPositionAgent  
                        + (x_pixel_vec * screen_offset.mV[VX])
                        + (y_pixel_vec * screen_offset.mV[VY]);

        //if (mOnHUD)
        //{
        //      render_position.mV[VY] -= fmodf(render_position.mV[VY], 1.f / (F32)gViewerWindow->getWindowWidth());
        //      render_position.mV[VZ] -= fmodf(render_position.mV[VZ], 1.f / (F32)gViewerWindow->getWindowHeight());
        //}
        //else
        //{
        //      render_position = gCamera->roundToPixel(render_position);
        //}

        if (mUseBubble)
        {
                LLGLDepthTest gls_depth(GL_TRUE, GL_FALSE);
                LLUI::pushMatrix();
                {
                        LLVector3 bg_pos = render_position
                                + (F32)mOffsetY * y_pixel_vec
                                - (width_vec / 2.f)
                                - (height_vec);
                        LLUI::translate(bg_pos.mV[VX], bg_pos.mV[VY], bg_pos.mV[VZ]);

                        if (for_select)
                        {
                                LLGLSNoTexture no_texture_state;
                                S32 name = mSourceObject->mGLName;
                                LLColor4U coloru((U8)(name >> 16), (U8)(name >> 8), (U8)name);
                                glColor4ubv(coloru.mV);
                                gl_segmented_rect_3d_tex(border_scale_vec, scaled_border_width, scaled_border_height, width_vec, height_vec);
                                LLUI::popMatrix();
                                return;
                        }
                        else
                        {
                                LLViewerImage::bindTexture(imagep);
                                
                                glColor4fv(bg_color.mV);
                                gl_segmented_rect_3d_tex(border_scale_vec, scaled_border_width, scaled_border_height, width_vec, height_vec);
                
                                if ( mLabelSegments.size())
                                {
                                        LLUI::pushMatrix();
                                        {
                                                glColor4f(text_color.mV[VX], text_color.mV[VY], text_color.mV[VZ], gSavedSettings.getF32("ChatBubbleOpacity") * alpha_factor);
                                                LLVector3 label_height = (mFontp->getLineHeight() * mLabelSegments.size() + (VERTICAL_PADDING / 3.f)) * y_pixel_vec;
                                                LLVector3 label_offset = height_vec - label_height;
                                                LLUI::translate(label_offset.mV[VX], label_offset.mV[VY], label_offset.mV[VZ]);
                                                gl_segmented_rect_3d_tex_top(border_scale_vec, scaled_border_width, scaled_border_height, width_vec, label_height);
                                        }
                                        LLUI::popMatrix();
                                }
                        }

                        BOOL outside_width = llabs(mPositionOffset.mV[VX]) > mWidth * 0.5f;
                        BOOL outside_height = llabs(mPositionOffset.mV[VY] + (mVertAlignment == ALIGN_VERT_TOP ? mHeight * 0.5f : 0.f)) > mHeight * (mVertAlignment == ALIGN_VERT_TOP ? mHeight * 0.75f : 0.5f);

                        // draw line segments pointing to parent object
                        if (!mOffscreen && (outside_width || outside_height))
                        {
                                LLUI::pushMatrix();
                                {
                                        glColor4fv(bg_color.mV);
                                        LLVector3 target_pos = -1.f * (mPositionOffset.mV[VX] * x_pixel_vec + mPositionOffset.mV[VY] * y_pixel_vec);
                                        target_pos += (width_vec / 2.f);
                                        target_pos += mVertAlignment == ALIGN_VERT_CENTER ? (height_vec * 0.5f) : LLVector3::zero;
                                        target_pos -= 3.f * x_pixel_vec;
                                        target_pos -= 6.f * y_pixel_vec;
                                        LLUI::translate(target_pos.mV[VX], target_pos.mV[VY], target_pos.mV[VZ]);
                                        gl_segmented_rect_3d_tex(border_scale_vec, 3.f * x_pixel_vec, 3.f * y_pixel_vec, 6.f * x_pixel_vec, 6.f * y_pixel_vec); 
                                }
                                LLUI::popMatrix();

                                
                                LLGLDisable gls_texture_2d(GL_TEXTURE_2D);
                                LLGLDepthTest gls_depth(mZCompare ? GL_TRUE : GL_FALSE, GL_FALSE);
                                
                                LLVector3 box_center_offset;
                                box_center_offset = (width_vec * 0.5f) + (height_vec * 0.5f);
                                LLUI::translate(box_center_offset.mV[VX], box_center_offset.mV[VY], box_center_offset.mV[VZ]);
                                glColor4fv(bg_color.mV);
                                LLUI::setLineWidth(2.0);
                                glBegin(GL_LINES);
                                {
                                        if (outside_width)
                                        {
                                                LLVector3 vert;
                                                // draw line in x then y
                                                if (mPositionOffset.mV[VX] < 0.f)
                                                {
                                                        // start at right edge
                                                        vert = width_vec * 0.5f;
                                                        glVertex3fv(vert.mV);
                                                }
                                                else
                                                {
                                                        // start at left edge
                                                        vert = width_vec * -0.5f;
                                                        glVertex3fv(vert.mV);
                                                }
                                                vert = -mPositionOffset.mV[VX] * x_pixel_vec;
                                                glVertex3fv(vert.mV);
                                                glVertex3fv(vert.mV);
                                                vert -= mPositionOffset.mV[VY] * y_pixel_vec;
                                                vert -= ((mVertAlignment == ALIGN_VERT_TOP) ? (height_vec * 0.5f) : LLVector3::zero);
                                                glVertex3fv(vert.mV);
                                        }
                                        else
                                        {
                                                LLVector3 vert;
                                                // draw line in y then x
                                                if (mPositionOffset.mV[VY] < 0.f)
                                                {
                                                        // start at top edge
                                                        vert = (height_vec * 0.5f) - (mPositionOffset.mV[VX] * x_pixel_vec);
                                                        glVertex3fv(vert.mV);
                                                }
                                                else
                                                {
                                                        // start at bottom edge
                                                        vert = (height_vec * -0.5f)  - (mPositionOffset.mV[VX] * x_pixel_vec);
                                                        glVertex3fv(vert.mV);
                                                }
                                                vert = -mPositionOffset.mV[VY] * y_pixel_vec - mPositionOffset.mV[VX] * x_pixel_vec;
                                                vert -= ((mVertAlignment == ALIGN_VERT_TOP) ? (height_vec * 0.5f) : LLVector3::zero);
                                                glVertex3fv(vert.mV);
                                        }
                                }
                                glEnd();
                                LLUI::setLineWidth(1.0);

                        }
                }
                LLUI::popMatrix();
        }

        F32 y_offset = (F32)mOffsetY;
                
        // Render label
        {
                glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);

                for(std::vector<LLHUDTextSegment>::iterator segment_iter = mLabelSegments.begin();
                        segment_iter != mLabelSegments.end(); ++segment_iter )
                {
                        const LLFontGL* fontp = (segment_iter->mStyle == LLFontGL::BOLD) ? mBoldFontp : mFontp;
                        y_offset -= fontp->getLineHeight();

                        F32 x_offset;
                        if (mTextAlignment == ALIGN_TEXT_CENTER)
                        {
                                x_offset = -0.5f*segment_iter->getWidth(fontp);
                        }
                        else // ALIGN_LEFT
                        {
                                x_offset = -0.5f * mWidth + (HORIZONTAL_PADDING / 2.f);
                        }

                        LLColor4 label_color(0.f, 0.f, 0.f, 1.f);
                        label_color.mV[VALPHA] = alpha_factor;
                        hud_render_text(segment_iter->getText(), render_position, *fontp, segment_iter->mStyle, x_offset, y_offset, label_color, mOnHUDAttachment);
                }
        }

        // Render text
        {
                // -1 mMaxLines means unlimited lines.
                S32 start_segment;
                S32 max_lines = getMaxLines();

                if (max_lines < 0) 
                {
                        start_segment = 0;
                }
                else 
                {
                        start_segment = llmax((S32)0, (S32)mTextSegments.size() - max_lines);
                }

                for (std::vector<LLHUDTextSegment>::iterator segment_iter = mTextSegments.begin() + start_segment;
                         segment_iter != mTextSegments.end(); ++segment_iter )
                {
                        const LLFontGL* fontp = (segment_iter->mStyle == LLFontGL::BOLD) ? mBoldFontp : mFontp;
                        y_offset -= fontp->getLineHeight();

                        U8 style = segment_iter->mStyle;
                        if (mDropShadow)
                        {
                                style |= LLFontGL::DROP_SHADOW;
                        }
        
                        F32 x_offset;
                        if (mTextAlignment== ALIGN_TEXT_CENTER)
                        {
                                x_offset = -0.5f*segment_iter->getWidth(fontp);
                        }
                        else // ALIGN_LEFT
                        {
                                x_offset = -0.5f * mWidth + (HORIZONTAL_PADDING / 2.f);
                        }

                        text_color = segment_iter->mColor;
                        text_color.mV[VALPHA] *= alpha_factor;

                        hud_render_text(segment_iter->getText(), render_position, *fontp, style, x_offset, y_offset, text_color, mOnHUDAttachment);
                }
        }
}

void LLHUDText::setStringUTF8(const std::string &wtext)
{
        setString(utf8str_to_wstring(wtext));
}

void LLHUDText::setString(const LLWString &wtext)
{
        mTextSegments.clear();
        addLine(wtext, mColor);
}

void LLHUDText::clearString()
{
        mTextSegments.clear();
}


void LLHUDText::addLine(const std::string &str, const LLColor4& color, const LLFontGL::StyleFlags style)
{
        addLine(utf8str_to_wstring(str), color, style);
}


void LLHUDText::addLine(const LLWString &wstr, const LLColor4& color, const LLFontGL::StyleFlags style)
{
        if (gNoRender)
        {
                return;
        }
        if (!wstr.empty())
        {
                LLWString wline(wstr);
                typedef boost::tokenizer<boost::char_separator<llwchar>, LLWString::const_iterator, LLWString > tokenizer;
                LLWString seps(utf8str_to_wstring("\r\n"));
                boost::char_separator<llwchar> sep(seps.c_str());

                tokenizer tokens(wline, sep);
                tokenizer::iterator iter = tokens.begin();

                while (iter != tokens.end())
                {
                        U32 line_length = 0;
                        do      
                        {
                                S32 segment_length = mFontp->maxDrawableChars(iter->substr(line_length).c_str(), mUseBubble ? HUD_TEXT_MAX_WIDTH : HUD_TEXT_MAX_WIDTH_NO_BUBBLE, wline.length(), TRUE);
                                mTextSegments.push_back(LLHUDTextSegment(iter->substr(line_length, segment_length), style, color));
                                line_length += segment_length;
                        }
                        while (line_length != iter->size());
                        ++iter;
                }
        }
}

void LLHUDText::setLabel(const std::string &label)
{
        setLabel(utf8str_to_wstring(label));
}

void LLHUDText::setLabel(const LLWString &wlabel)
{
        mLabelSegments.clear();

        if (!wlabel.empty())
        {
                LLWString wstr(wlabel);
                LLWString seps(utf8str_to_wstring("\r\n"));
                LLWString empty;

                typedef boost::tokenizer<boost::char_separator<llwchar>, LLWString::const_iterator, LLWString > tokenizer;
                boost::char_separator<llwchar> sep(seps.c_str(), empty.c_str(), boost::keep_empty_tokens);

                tokenizer tokens(wstr, sep);
                tokenizer::iterator iter = tokens.begin();

                while (iter != tokens.end())
                {
                        U32 line_length = 0;
                        do      
                        {
                                S32 segment_length = mFontp->maxDrawableChars(iter->substr(line_length).c_str(), mUseBubble ? HUD_TEXT_MAX_WIDTH : HUD_TEXT_MAX_WIDTH_NO_BUBBLE, wstr.length(), TRUE);
                                mLabelSegments.push_back(LLHUDTextSegment(iter->substr(line_length, segment_length), LLFontGL::NORMAL, mColor));
                                line_length += segment_length;
                        }
                        while (line_length != iter->size());
                        ++iter;
                }
        }
}

void LLHUDText::setDropShadow(const BOOL do_shadow)
{
        mDropShadow = do_shadow;
}

void LLHUDText::setZCompare(const BOOL zcompare)
{
        mZCompare = zcompare;
}

void LLHUDText::setFont(const LLFontGL* font)
{
        mFontp = font;
}


void LLHUDText::setColor(const LLColor4 &color)
{
        mColor = color;
        for (std::vector<LLHUDTextSegment>::iterator segment_iter = mTextSegments.begin();
                 segment_iter != mTextSegments.end(); ++segment_iter )
        {
                segment_iter->mColor = color;
        }
}

void LLHUDText::setBackgroundColor(const LLColor4 &color)
{
        mBackgroundColor = color;
}

void LLHUDText::setUsePixelSize(const BOOL use_pixel_size)
{
        mUsePixelSize = use_pixel_size;
}

void LLHUDText::setDoFade(const BOOL do_fade)
{
        mDoFade = do_fade;
}

void LLHUDText::updateVisibility()
{
        if (mSourceObject)
        {
                mSourceObject->updateText();
        }
        
        mPositionAgent = gAgent.getPosAgentFromGlobal(mPositionGlobal);

        if (!mSourceObject)
        {
                //llwarns << "LLHUDText::updateScreenPos -- mSourceObject is NULL!" << llendl;
                mVisible = TRUE;
                if (mOnHUDAttachment)
                {
                        sVisibleHUDTextObjects.push_back(LLPointer<LLHUDText> (this));
                }
                else
                {
                        sVisibleTextObjects.push_back(LLPointer<LLHUDText> (this));
                }
                return;
        }

        // Not visible if parent object is dead
        if (mSourceObject->isDead())
        {
                mVisible = FALSE;
                return;
        }

        // for now, all text on hud objects is visible
        if (mOnHUDAttachment)
        {
                mVisible = TRUE;
                sVisibleHUDTextObjects.push_back(LLPointer<LLHUDText> (this));
                mLastDistance = mPositionAgent.mV[VX];
                return;
        }

        // push text towards camera by radius of object, but not past camera
        LLVector3 vec_from_camera = mPositionAgent - gCamera->getOrigin();
        LLVector3 dir_from_camera = vec_from_camera;
        dir_from_camera.normVec();

        if (dir_from_camera * gCamera->getAtAxis() <= 0.f)
        {
                mPositionAgent -= projected_vec(vec_from_camera, gCamera->getAtAxis()) * 1.f;
                mPositionAgent += gCamera->getAtAxis() * (gCamera->getNear() + 0.1f);
        }
        else if (vec_from_camera * gCamera->getAtAxis() <= gCamera->getNear() + 0.1f + mSourceObject->getVObjRadius())
        {
                mPositionAgent = gCamera->getOrigin() + vec_from_camera * ((gCamera->getNear() + 0.1f) / (vec_from_camera * gCamera->getAtAxis()));
        }
        else
        {
                mPositionAgent -= dir_from_camera * mSourceObject->getVObjRadius();
        }

        mLastDistance = (mPositionAgent - gCamera->getOrigin()).magVec();

        if (mLOD >= 3 || !mTextSegments.size() || (mDoFade && (mLastDistance > mFadeDistance + mFadeRange)))
        {
                mVisible = FALSE;
                return;
        }

        LLVector3 x_pixel_vec;
        LLVector3 y_pixel_vec;

        gCamera->getPixelVectors(mPositionAgent, y_pixel_vec, x_pixel_vec);

        LLVector3 render_position = mPositionAgent +                    
                        (x_pixel_vec * mPositionOffset.mV[VX]) +
                        (y_pixel_vec * mPositionOffset.mV[VY]);

        mOffscreen = FALSE;
        if (!gCamera->sphereInFrustum(render_position, mRadius))
        {
                if (!mVisibleOffScreen)
                {
                        mVisible = FALSE;
                        return;
                }
                else
                {
                        mOffscreen = TRUE;
                }
        }

        mVisible = TRUE;
        sVisibleTextObjects.push_back(LLPointer<LLHUDText> (this));
}

LLVector2 LLHUDText::updateScreenPos(LLVector2 &offset)
{
        LLCoordGL screen_pos;
        LLVector2 screen_pos_vec;
        LLVector3 x_pixel_vec;
        LLVector3 y_pixel_vec;
        gCamera->getPixelVectors(mPositionAgent, y_pixel_vec, x_pixel_vec);
        LLVector3 world_pos = mPositionAgent + (offset.mV[VX] * x_pixel_vec) + (offset.mV[VY] * y_pixel_vec);
        if (!gCamera->projectPosAgentToScreen(world_pos, screen_pos, FALSE) && mVisibleOffScreen)
        {
                // bubble off-screen, so find a spot for it along screen edge
                LLVector2 window_center(gViewerWindow->getWindowDisplayWidth() * 0.5f, gViewerWindow->getWindowDisplayHeight() * 0.5f);
                LLVector2 delta_from_center(screen_pos.mX - window_center.mV[VX], 
                                                                        screen_pos.mY - window_center.mV[VY]);
                delta_from_center.normVec();

                F32 camera_aspect = gCamera->getAspect();
                F32 delta_aspect = llabs(delta_from_center.mV[VX] / delta_from_center.mV[VY]);
                if (camera_aspect / llmax(delta_aspect, 0.001f) > 1.f)
                {
                        // camera has wider aspect ratio than offset vector, so clamp to height
                        delta_from_center *= llabs(window_center.mV[VY] / delta_from_center.mV[VY]);
                }
                else
                {
                        // camera has narrower aspect ratio than offset vector, so clamp to width
                        delta_from_center *= llabs(window_center.mV[VX] / delta_from_center.mV[VX]);
                }

                screen_pos_vec = window_center + delta_from_center;
        }
        else
        {
                screen_pos_vec.setVec((F32)screen_pos.mX, (F32)screen_pos.mY);
        }
        S32 bottom = STATUS_BAR_HEIGHT;
        if (gChatBar->getVisible())
        {
                bottom += CHAT_BAR_HEIGHT;
        }

        LLVector2 screen_center;
        screen_center.mV[VX] = llclamp((F32)screen_pos_vec.mV[VX], mWidth * 0.5f, (F32)gViewerWindow->getWindowDisplayWidth() - mWidth * 0.5f);

        if(mVertAlignment == ALIGN_VERT_TOP)
        {
                screen_center.mV[VY] = llclamp((F32)screen_pos_vec.mV[VY], 
                        (F32)bottom, 
                        (F32)gViewerWindow->getWindowDisplayHeight() - mHeight - (F32)MENU_BAR_HEIGHT);
                mSoftScreenRect.setLeftTopAndSize(screen_center.mV[VX] - (mWidth + BUFFER_SIZE) * 0.5f, 
                        screen_center.mV[VY] + (mHeight + BUFFER_SIZE), mWidth + BUFFER_SIZE, mHeight + BUFFER_SIZE);
        }
        else
        {
                screen_center.mV[VY] = llclamp((F32)screen_pos_vec.mV[VY], 
                        (F32)bottom + mHeight * 0.5f, 
                        (F32)gViewerWindow->getWindowDisplayHeight() - mHeight * 0.5f - (F32)MENU_BAR_HEIGHT);
                mSoftScreenRect.setCenterAndSize(screen_center.mV[VX], screen_center.mV[VY], mWidth + BUFFER_SIZE, mHeight + BUFFER_SIZE);
        }

        return offset + (screen_center - LLVector2((F32)screen_pos.mX, (F32)screen_pos.mY));
}

void LLHUDText::updateSize()
{
        F32 width = 0.f;

        S32 max_lines = getMaxLines();
        S32 lines = (max_lines < 0) ? (S32)mTextSegments.size() : llmin((S32)mTextSegments.size(), max_lines);

        F32 height = (F32)mFontp->getLineHeight() * (lines + mLabelSegments.size());

        S32 start_segment;
        if (max_lines < 0) start_segment = 0;
        else start_segment = llmax((S32)0, (S32)mTextSegments.size() - max_lines);

        std::vector<LLHUDTextSegment>::iterator iter = mTextSegments.begin() + start_segment;
        while (iter != mTextSegments.end())
        {
                width = llmax(width, llmin(iter->getWidth(mFontp), HUD_TEXT_MAX_WIDTH));
                ++iter;
        }

        iter = mLabelSegments.begin();
        while (iter != mLabelSegments.end())
        {
                width = llmax(width, llmin(iter->getWidth(mFontp), HUD_TEXT_MAX_WIDTH));
                ++iter;
        }
        
        if (width == 0.f)
        {
                return;
        }

        width += HORIZONTAL_PADDING;
        height += VERTICAL_PADDING;

        if (!mResizeTimer.getStarted() && (width != mWidth || height != mHeight))
        {
                mResizeTimer.start();
        }

        // *NOTE: removed logic which did a divide by zero.
        F32 u = 1.f;//llclamp(mResizeTimer.getElapsedTimeF32() / RESIZE_TIME, 0.f, 1.f);
        if (u == 1.f)
        {
                mResizeTimer.stop();
        }

        mWidth = llmax(width, lerp(mWidth, (F32)width, u));
        mHeight = llmax(height, lerp(mHeight, (F32)height, u));
}

void LLHUDText::updateAll()
{
        // iterate over all text objects, calculate their restoration forces,
        // and add them to the visible set if they are on screen and close enough
        sVisibleTextObjects.clear();
        sVisibleHUDTextObjects.clear();
        
        TextObjectIterator text_it;
        for (text_it = sTextObjects.begin(); text_it != sTextObjects.end(); ++text_it)
        {
                LLHUDText* textp = (*text_it);
                textp->mTargetPositionOffset.clearVec();
                textp->updateSize();
                textp->updateVisibility();
        }
        
        // sort back to front for rendering purposes
        std::sort(sVisibleTextObjects.begin(), sVisibleTextObjects.end(), lltextobject_further_away());
        std::sort(sVisibleHUDTextObjects.begin(), sVisibleHUDTextObjects.end(), lltextobject_further_away());

        // iterate from front to back, and set LOD based on current screen coverage
        F32 screen_area = (F32)(gViewerWindow->getWindowWidth() * gViewerWindow->getWindowHeight());
        F32 current_screen_area = 0.f;
        std::vector<LLPointer<LLHUDText> >::reverse_iterator r_it;
        for (r_it = sVisibleTextObjects.rbegin(); r_it != sVisibleTextObjects.rend(); ++r_it)
        {
                LLHUDText* textp = (*r_it);
                if (textp->mUseBubble)
                {
                        if (current_screen_area / screen_area > LOD_2_SCREEN_COVERAGE)
                        {
                                textp->setLOD(3);
                        }
                        else if (current_screen_area / screen_area > LOD_1_SCREEN_COVERAGE)
                        {
                                textp->setLOD(2);
                        }
                        else if (current_screen_area / screen_area > LOD_0_SCREEN_COVERAGE)
                        {
                                textp->setLOD(1);
                        }
                        else
                        {
                                textp->setLOD(0);
                        }
                        textp->updateSize();
                        // find on-screen position and initialize collision rectangle
                        textp->mTargetPositionOffset = textp->updateScreenPos(LLVector2::zero);
                        current_screen_area += (F32)(textp->mSoftScreenRect.getWidth() * textp->mSoftScreenRect.getHeight());
                }
        }

        LLStat* camera_vel_stat = gCamera->getVelocityStat();
        F32 camera_vel = camera_vel_stat->getCurrent();
        if (camera_vel > MAX_STABLE_CAMERA_VELOCITY)
        {
                return;
        }

        VisibleTextObjectIterator src_it;

        for (S32 i = 0; i < NUM_OVERLAP_ITERATIONS; i++)
        {
                for (src_it = sVisibleTextObjects.begin(); src_it != sVisibleTextObjects.end(); ++src_it)
                {
                        LLHUDText* src_textp = (*src_it);

                        if (!src_textp->mUseBubble)
                        {
                                continue;
                        }
                        VisibleTextObjectIterator dst_it = src_it;
                        ++dst_it;
                        for (; dst_it != sVisibleTextObjects.end(); ++dst_it)
                        {
                                LLHUDText* dst_textp = (*dst_it);

                                if (!dst_textp->mUseBubble)
                                {
                                        continue;
                                }
                                if (src_textp->mSoftScreenRect.rectInRect(&dst_textp->mSoftScreenRect))
                                {
                                        LLRectf intersect_rect = src_textp->mSoftScreenRect;
                                        intersect_rect.intersectWith(dst_textp->mSoftScreenRect);
                                        intersect_rect.stretch(-BUFFER_SIZE * 0.5f);
                                        
                                        F32 src_center_x = src_textp->mSoftScreenRect.getCenterX();
                                        F32 src_center_y = src_textp->mSoftScreenRect.getCenterY();
                                        F32 dst_center_x = dst_textp->mSoftScreenRect.getCenterX();
                                        F32 dst_center_y = dst_textp->mSoftScreenRect.getCenterY();
                                        F32 intersect_center_x = intersect_rect.getCenterX();
                                        F32 intersect_center_y = intersect_rect.getCenterY();
                                        LLVector2 force = lerp(LLVector2(dst_center_x - intersect_center_x, dst_center_y - intersect_center_y), 
                                                                                LLVector2(intersect_center_x - src_center_x, intersect_center_y - src_center_y),
                                                                                0.5f);
                                        force.setVec(dst_center_x - src_center_x, dst_center_y - src_center_y);
                                        force.normVec();

                                        LLVector2 src_force = -1.f * force;
                                        LLVector2 dst_force = force;

                                        LLVector2 force_strength;
                                        F32 src_mult = dst_textp->mMass / (dst_textp->mMass + src_textp->mMass); 
                                        F32 dst_mult = 1.f - src_mult;
                                        F32 src_aspect_ratio = src_textp->mSoftScreenRect.getWidth() / src_textp->mSoftScreenRect.getHeight();
                                        F32 dst_aspect_ratio = dst_textp->mSoftScreenRect.getWidth() / dst_textp->mSoftScreenRect.getHeight();
                                        src_force.mV[VY] *= src_aspect_ratio;
                                        src_force.normVec();
                                        dst_force.mV[VY] *= dst_aspect_ratio;
                                        dst_force.normVec();

                                        src_force.mV[VX] *= llmin(intersect_rect.getWidth() * src_mult, intersect_rect.getHeight() * SPRING_STRENGTH);
                                        src_force.mV[VY] *= llmin(intersect_rect.getHeight() * src_mult, intersect_rect.getWidth() * SPRING_STRENGTH);
                                        dst_force.mV[VX] *=  llmin(intersect_rect.getWidth() * dst_mult, intersect_rect.getHeight() * SPRING_STRENGTH);
                                        dst_force.mV[VY] *=  llmin(intersect_rect.getHeight() * dst_mult, intersect_rect.getWidth() * SPRING_STRENGTH);
                                        
                                        src_textp->mTargetPositionOffset += src_force;
                                        dst_textp->mTargetPositionOffset += dst_force;
                                        src_textp->mTargetPositionOffset = src_textp->updateScreenPos(src_textp->mTargetPositionOffset);
                                        dst_textp->mTargetPositionOffset = dst_textp->updateScreenPos(dst_textp->mTargetPositionOffset);
                                }
                        }
                }
        }

        VisibleTextObjectIterator this_object_it;
        for (this_object_it = sVisibleTextObjects.begin(); this_object_it != sVisibleTextObjects.end(); ++this_object_it)
        {
                if (!(*this_object_it)->mUseBubble)
                {
                        continue;
                }
                (*this_object_it)->mPositionOffset = lerp((*this_object_it)->mPositionOffset, (*this_object_it)->mTargetPositionOffset, LLCriticalDamp::getInterpolant(POSITION_DAMPING_TC));
        }
}

void LLHUDText::setLOD(S32 lod)
{
        mLOD = lod;
        //RN: uncomment this to visualize LOD levels
        //char label[255];
        //sprintf(label, "%d", lod);
        //setLabel(label);
}

S32 LLHUDText::getMaxLines()
{
        switch(mLOD)
        {
        case 0:
                return mMaxLines;
        case 1:
                return mMaxLines > 0 ? mMaxLines / 2 : 5;
        case 2:
                return mMaxLines > 0 ? mMaxLines / 3 : 2;
        default:
                // label only
                return 0;
        }
}

void LLHUDText::markDead()
{
        sTextObjects.erase(LLPointer<LLHUDText>(this));
        LLHUDObject::markDead();
}

void LLHUDText::renderAllHUD()
{
        LLGLEnable color_mat(GL_COLOR_MATERIAL);
        LLGLDepthTest depth(GL_FALSE, GL_FALSE);
        
        VisibleTextObjectIterator text_it;

        for (text_it = sVisibleHUDTextObjects.begin(); text_it != sVisibleHUDTextObjects.end(); ++text_it)
        {
                (*text_it)->renderText(FALSE);
        }
}

//static 
void LLHUDText::addPickable(std::set<LLViewerObject*> &pick_list)
{
        //this might put an object on the pick list a second time, overriding it's mGLName, which is ok
        // *FIX: we should probably cull against pick frustum
        VisibleTextObjectIterator text_it;
        for (text_it = sVisibleTextObjects.begin(); text_it != sVisibleTextObjects.end(); ++text_it)
        {
                if (!(*text_it)->mUseBubble)
                {
                        continue;
                }
                pick_list.insert((*text_it)->mSourceObject);
        }
}

//static
// called when UI scale changes, to flush font width caches
void LLHUDText::reshape()
{
        TextObjectIterator text_it;
        for (text_it = sTextObjects.begin(); text_it != sTextObjects.end(); ++text_it)
        {
                LLHUDText* textp = (*text_it);
                std::vector<LLHUDTextSegment>::iterator segment_iter; 
                for (segment_iter = textp->mTextSegments.begin();
                         segment_iter != textp->mTextSegments.end(); ++segment_iter )
                {
                        segment_iter->clearFontWidthMap();
                }
                for(segment_iter = textp->mLabelSegments.begin();
                        segment_iter != textp->mLabelSegments.end(); ++segment_iter )
                {
                        segment_iter->clearFontWidthMap();
                }               
        }
}

//============================================================================

F32 LLHUDText::LLHUDTextSegment::getWidth(const LLFontGL* font)
{
        std::map<const LLFontGL*, F32>::iterator iter = mFontWidthMap.find(font);
        if (iter != mFontWidthMap.end())
        {
                return iter->second;
        }
        else
        {
                F32 width = font->getWidthF32(mText.c_str());
                mFontWidthMap[font] = width;
                return width;
        }
}

---