/**
 * @file llfasttimerview.cpp
 * @brief LLFastTimerView class implementation
 *
 * $LicenseInfo:firstyear=2004&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2010, Linden Research, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

#include "llviewerprecompiledheaders.h"

#include "llfasttimerview.h"

#include "llviewerwindow.h"
#include "llrect.h"
#include "llcombobox.h"
#include "llerror.h"
#include "llgl.h"
#include "llimagepng.h"
#include "llrender.h"
#include "llrendertarget.h"
#include "lllocalcliprect.h"
#include "lllayoutstack.h"
#include "llmath.h"
#include "llfontgl.h"
#include "llsdserialize.h"
#include "lltooltip.h"
#include "llbutton.h"
#include "llscrollbar.h"

#include "llappviewer.h"
#include "llviewertexturelist.h"
#include "llui.h"
#include "llviewercontrol.h"

#include "llfasttimer.h"
#include "lltreeiterators.h"
#include "llmetricperformancetester.h"
#include "llviewerstats.h"

//////////////////////////////////////////////////////////////////////////////

using namespace LLTrace;

static constexpr S32 MAX_VISIBLE_HISTORY = 12;
static constexpr S32 LINE_GRAPH_HEIGHT = 240;
static constexpr S32 MIN_BAR_HEIGHT = 3;
static constexpr S32 RUNNING_AVERAGE_WIDTH = 100;
static constexpr S32 NUM_FRAMES_HISTORY = 200;

std::vector<BlockTimerStatHandle*> ft_display_idx; // line of table entry for display purposes (for collapse)

bool LLFastTimerView::sAnalyzePerformance = false;

S32 get_depth(const BlockTimerStatHandle* blockp)
{
    S32 depth = 0;
    BlockTimerStatHandle* timerp = blockp->getParent();
    while(timerp)
    {
        depth++;
        if (timerp->getParent() == timerp) break;
        timerp = timerp->getParent();
    }
    return depth;
}

LLFastTimerView::LLFastTimerView(const LLSD& key)
:   LLFloater(key),
    mHoverTimer(NULL),
    mDisplayMode(0),
    mDisplayType(DISPLAY_TIME),
    mScrollIndex(0),
    mHoverID(NULL),
    mHoverBarIndex(-1),
    mStatsIndex(-1),
    mPauseHistory(false),
    mRecording(NUM_FRAMES_HISTORY)
{
    mTimerBarRows.resize(NUM_FRAMES_HISTORY);
}

LLFastTimerView::~LLFastTimerView()
{
}

void LLFastTimerView::onPause()
{
    setPauseState(!mPauseHistory);
}

void LLFastTimerView::setPauseState(bool pause_state)
{
    if (pause_state == mPauseHistory) return;

    // reset scroll to bottom when unpausing
    if (!pause_state)
    {

        getChild<LLButton>("pause_btn")->setLabel(getString("pause"));
    }
    else
    {
        mScrollIndex = 0;

        getChild<LLButton>("pause_btn")->setLabel(getString("run"));
    }

    mPauseHistory = pause_state;
}

bool LLFastTimerView::postBuild()
{
    LLButton& pause_btn = getChildRef<LLButton>("pause_btn");
    mScrollBar = getChild<LLScrollbar>("scroll_vert");

    pause_btn.setCommitCallback(boost::bind(&LLFastTimerView::onPause, this));
    return true;
}

bool LLFastTimerView::handleRightMouseDown(S32 x, S32 y, MASK mask)
{
    if (mHoverTimer )
    {
        // right click collapses timers
        if (!mHoverTimer->getTreeNode().mCollapsed)
        {
            mHoverTimer->getTreeNode().mCollapsed = true;
        }
        else if (mHoverTimer->getParent())
        {
            mHoverTimer->getParent()->getTreeNode().mCollapsed = true;
        }
        return true;
    }
    else if (mBarRect.pointInRect(x, y))
    {
        S32 bar_idx = MAX_VISIBLE_HISTORY - ((y - mBarRect.mBottom) * (MAX_VISIBLE_HISTORY + 2) / mBarRect.getHeight());
        bar_idx = llclamp(bar_idx, 0, MAX_VISIBLE_HISTORY);
        mStatsIndex = mScrollIndex + bar_idx;
        return true;
    }
    return LLFloater::handleRightMouseDown(x, y, mask);
}

BlockTimerStatHandle* LLFastTimerView::getLegendID(S32 y)
{
    S32 idx = (mLegendRect.mTop - y) / (LLFontGL::getFontMonospace()->getLineHeight() + 2);

    if (idx >= 0 && idx < (S32)ft_display_idx.size())
    {
        return ft_display_idx[idx];
    }

    return NULL;
}

bool LLFastTimerView::handleDoubleClick(S32 x, S32 y, MASK mask)
{
    for(LLTrace::block_timer_tree_df_iterator_t it = LLTrace::begin_block_timer_tree_df(FTM_FRAME);
        it != LLTrace::end_block_timer_tree_df();
        ++it)
    {
        (*it)->getTreeNode().mCollapsed = false;
    }
    return true;
}

bool LLFastTimerView::handleMouseDown(S32 x, S32 y, MASK mask)
{
    if (x < mScrollBar->getRect().mLeft)
    {
        BlockTimerStatHandle* idp = getLegendID(y);
        if (idp)
        {
            idp->getTreeNode().mCollapsed = !idp->getTreeNode().mCollapsed;
        }
    }
    else if (mHoverTimer)
    {
        //left click drills down by expanding timers
        mHoverTimer->getTreeNode().mCollapsed = false;
    }
    else if (mGraphRect.pointInRect(x, y))
    {
        gFocusMgr.setMouseCapture(this);
        return true;
    }

    return LLFloater::handleMouseDown(x, y, mask);
}

bool LLFastTimerView::handleMouseUp(S32 x, S32 y, MASK mask)
{
    if (hasMouseCapture())
    {
        gFocusMgr.setMouseCapture(NULL);
    }
    return LLFloater::handleMouseUp(x, y, mask);;
}

bool LLFastTimerView::handleHover(S32 x, S32 y, MASK mask)
{
    if (hasMouseCapture())
    {
        F32 lerp = llclamp(1.f - (F32) (x - mGraphRect.mLeft) / (F32) mGraphRect.getWidth(), 0.f, 1.f);
        mScrollIndex = ll_round( lerp * (F32)(mRecording.getNumRecordedPeriods() - MAX_VISIBLE_HISTORY));
        mScrollIndex = llclamp( mScrollIndex, 0, (S32)mRecording.getNumRecordedPeriods());
        return true;
    }
    mHoverTimer = NULL;
    mHoverID = NULL;

    if(mPauseHistory && mBarRect.pointInRect(x, y))
    {
        //const S32 bars_top = mBarRect.mTop;
        const S32 bars_top = mBarRect.mTop - ((S32)LLFontGL::getFontMonospace()->getLineHeight() + 4);

        mHoverBarIndex = llmin((bars_top - y) / (mBarRect.getHeight() / (MAX_VISIBLE_HISTORY + 2)) - 1,
                                (S32)mRecording.getNumRecordedPeriods() - 1,
                                MAX_VISIBLE_HISTORY);
        if (mHoverBarIndex == 0)
        {
            return true;
        }
        else if (mHoverBarIndex < 0)
        {
            mHoverBarIndex = 0;
        }

        TimerBarRow& row = mHoverBarIndex == 0 ? mAverageTimerRow : mTimerBarRows[mScrollIndex + mHoverBarIndex - 1];

        TimerBar* hover_bar = NULL;
        F32Seconds mouse_time_offset = ((F32)(x - mBarRect.mLeft) / (F32)mBarRect.getWidth()) * mTotalTimeDisplay;
        for (size_t bar_index = 0, end_index = LLTrace::BlockTimerStatHandle::instance_tracker_t::instanceCount();
            bar_index < end_index;
            ++bar_index)
        {
            TimerBar& bar = row.mBars[bar_index];
            if (bar.mSelfStart > mouse_time_offset)
            {
                break;
            }
            if (bar.mSelfEnd > mouse_time_offset)
            {
                hover_bar = &bar;
                if (bar.mTimeBlock->getTreeNode().mCollapsed)
                {
                    // stop on first collapsed BlockTimerStatHandle, since we can't select any children
                    break;
                }
            }
        }

        if (hover_bar)
        {
            mHoverID = hover_bar->mTimeBlock;
            if (mHoverTimer != mHoverID)
            {
                // could be that existing tooltip is for a parent and is thus
                // covering region for this new timer, go ahead and unblock
                // so we can create a new tooltip
                LLToolTipMgr::instance().unblockToolTips();
                mHoverTimer = mHoverID;
                mToolTipRect.set(mBarRect.mLeft + (hover_bar->mSelfStart / mTotalTimeDisplay) * mBarRect.getWidth(),
                                row.mTop,
                                mBarRect.mLeft + (hover_bar->mSelfEnd / mTotalTimeDisplay) * mBarRect.getWidth(),
                                row.mBottom);
            }
        }
    }
    else if (x < mScrollBar->getRect().mLeft)
    {
        BlockTimerStatHandle* timer_id = getLegendID(y);
        if (timer_id)
        {
            mHoverID = timer_id;
        }
    }

    return LLFloater::handleHover(x, y, mask);
}


static std::string get_tooltip(BlockTimerStatHandle& timer, S32 history_index, PeriodicRecording& frame_recording)
{
    std::string tooltip;
    if (history_index == 0)
    {
        // by default, show average number of call
        tooltip = llformat("%s (%d ms, %d calls)", timer.getName().c_str(), (S32)F64Milliseconds(frame_recording.getPeriodMean (timer, RUNNING_AVERAGE_WIDTH)).value(), (S32)frame_recording.getPeriodMean(timer.callCount(), RUNNING_AVERAGE_WIDTH));
    }
    else
    {
        tooltip = llformat("%s (%d ms, %d calls)", timer.getName().c_str(), (S32)F64Milliseconds(frame_recording.getPrevRecording(history_index).getSum(timer)).value(), (S32)frame_recording.getPrevRecording(history_index).getSum(timer.callCount()));
    }
    return tooltip;
}

bool LLFastTimerView::handleToolTip(S32 x, S32 y, MASK mask)
{
    if(mPauseHistory && mBarRect.pointInRect(x, y))
    {
        // tooltips for timer bars
        if (mHoverTimer)
        {
            LLRect screen_rect;
            localRectToScreen(mToolTipRect, &screen_rect);

            std::string tooltip = get_tooltip(*mHoverTimer, mHoverBarIndex > 0 ? mScrollIndex + mHoverBarIndex : 0, mRecording);

            LLToolTipMgr::instance().show(LLToolTip::Params()
                .message(tooltip)
                .sticky_rect(screen_rect)
                .delay_time(0.f));

            return true;
        }
    }
    else
    {
        // tooltips for timer legend
        if (x < mScrollBar->getRect().mLeft)
        {
            BlockTimerStatHandle* idp = getLegendID(y);
            if (idp)
            {
                LLToolTipMgr::instance().show(get_tooltip(*idp, 0, mRecording));

                return true;
            }
        }
    }

    return LLFloater::handleToolTip(x, y, mask);
}

bool LLFastTimerView::handleScrollWheel(S32 x, S32 y, S32 clicks)
{
    if (x < mBarRect.mLeft)
    {
        // Inside mScrollBar and list of timers
        mScrollBar->handleScrollWheel(x,y,clicks);
    }
    else
    {
    setPauseState(true);
    mScrollIndex = llclamp( mScrollIndex + clicks,
                            0,
                            llmin((S32)mRecording.getNumRecordedPeriods(), (S32)mRecording.getNumRecordedPeriods() - MAX_VISIBLE_HISTORY));
    }
    return true;
}

static BlockTimerStatHandle FTM_RENDER_TIMER("Timers");
static const S32 MARGIN = 10;

static std::vector<LLColor4> sTimerColors;

void LLFastTimerView::draw()
{
    LL_RECORD_BLOCK_TIME(FTM_RENDER_TIMER);

    if (!mPauseHistory)
    {
        mRecording.appendRecording(LLTrace::get_frame_recording().getLastRecording());
        mTimerBarRows.pop_back();
        mTimerBarRows.push_front(TimerBarRow());
    }

    mDisplayMode = llclamp(getChild<LLComboBox>("time_scale_combo")->getCurrentIndex(), 0, 3);
    mDisplayType = (EDisplayType)llclamp(getChild<LLComboBox>("metric_combo")->getCurrentIndex(), 0, 2);

    generateUniqueColors();

    LLView::drawChildren();
    //getChild<LLLayoutStack>("timer_bars_stack")->updateLayout();
    //getChild<LLLayoutStack>("legend_stack")->updateLayout();
    LLView* bars_panel = getChildView("bars_panel");
    bars_panel->localRectToOtherView(bars_panel->getLocalRect(), &mBarRect, this);

    LLView* lines_panel = getChildView("lines_panel");
    lines_panel->localRectToOtherView(lines_panel->getLocalRect(), &mGraphRect, this);

    LLView* legend_panel = getChildView("legend");
    legend_panel->localRectToOtherView(legend_panel->getLocalRect(), &mLegendRect, this);

    // Draw the window background
            gGL.getTexUnit(0)->unbind(LLTexUnit::TT_TEXTURE);
    gl_rect_2d(getLocalRect(), LLColor4(0.f, 0.f, 0.f, 0.25f));

    drawHelp(getRect().getHeight() - MARGIN);
    drawLegend();

    //mBarRect.mLeft = MARGIN + LEGEND_WIDTH + 8;
    //mBarRect.mTop = y;
    //mBarRect.mRight = getRect().getWidth() - MARGIN;
    //mBarRect.mBottom = MARGIN + LINE_GRAPH_HEIGHT;

    drawBars();
    drawLineGraph();
    printLineStats();
    LLView::draw();

    mAllTimeMax = llmax(mAllTimeMax, mRecording.getLastRecording().getSum(FTM_FRAME));
    mHoverID = NULL;
    mHoverBarIndex = -1;
}

void LLFastTimerView::onOpen(const LLSD& key)
{
    setPauseState(false);
    mRecording.reset();
    mRecording.appendPeriodicRecording(LLTrace::get_frame_recording());
    for(std::deque<TimerBarRow>::iterator it = mTimerBarRows.begin(), end_it = mTimerBarRows.end();
        it != end_it;
        ++it)
    {
        delete []it->mBars;
        it->mBars = NULL;
    }
}

void LLFastTimerView::onClose(bool app_quitting)
{
    setVisible(false);
}

void saveChart(const std::string& label, const char* suffix, LLImageRaw* scratch)
{
    // disable use of glReadPixels which messes up nVidia nSight graphics debugging
    if (!LLRender::sNsightDebugSupport)
    {
        LLImageDataSharedLock lock(scratch);

        //read result back into raw image
        glReadPixels(0, 0, 1024, 512, GL_RGB, GL_UNSIGNED_BYTE, scratch->getData());

        //write results to disk
        LLPointer<LLImagePNG> result = new LLImagePNG();
        result->encode(scratch, 0.f);

        std::string ext = result->getExtension();
        std::string filename = llformat("%s_%s.%s", label.c_str(), suffix, ext.c_str());

        std::string out_file = gDirUtilp->getExpandedFilename(LL_PATH_LOGS, filename);
        result->save(out_file);
    }
}

//static
void LLFastTimerView::exportCharts(const std::string& base, const std::string& target)
{
    //allocate render target for drawing charts
    LLRenderTarget buffer;
    buffer.allocate(1024,512, GL_RGB);


    LLSD cur;

    LLSD base_data;

    { //read base log into memory
        S32 i = 0;
        llifstream is(base.c_str());
        while (!is.eof() && LLSDParser::PARSE_FAILURE != LLSDSerialize::fromXML(cur, is))
        {
            base_data[i++] = cur;
        }
        is.close();
    }

    LLSD cur_data;
    std::set<std::string> chart_names;

    { //read current log into memory
        S32 i = 0;
        llifstream is(target.c_str());
        while (!is.eof() && LLSDParser::PARSE_FAILURE != LLSDSerialize::fromXML(cur, is))
        {
            cur_data[i++] = cur;

            for (LLSD::map_iterator iter = cur.beginMap(); iter != cur.endMap(); ++iter)
            {
                std::string label = iter->first;
                chart_names.insert(label);
            }
        }
        is.close();
    }

    //allocate raw scratch space
    LLPointer<LLImageRaw> scratch = new LLImageRaw(1024, 512, 3);

    gGL.pushMatrix();
    gGL.loadIdentity();
    gGL.matrixMode(LLRender::MM_PROJECTION);
    gGL.loadIdentity();
    gGL.ortho(-0.05f, 1.05f, -0.05f, 1.05f, -1.0f, 1.0f);

    //render charts
    gGL.getTexUnit(0)->unbind(LLTexUnit::TT_TEXTURE);

    buffer.bindTarget();

    for (std::set<std::string>::iterator iter = chart_names.begin(); iter != chart_names.end(); ++iter)
    {
        std::string label = *iter;

        LLSD::Real max_time = 0.0;
        LLSD::Integer max_calls = 0;
        LLSD::Real max_execution = 0.0;

        std::vector<LLSD::Real> cur_execution;
        std::vector<LLSD::Real> cur_times;
        std::vector<LLSD::Integer> cur_calls;

        std::vector<LLSD::Real> base_execution;
        std::vector<LLSD::Real> base_times;
        std::vector<LLSD::Integer> base_calls;

        for (U32 i = 0; i < cur_data.size(); ++i)
        {
            LLSD::Real time = cur_data[i][label]["Time"].asReal();
            LLSD::Integer calls = cur_data[i][label]["Calls"].asInteger();

            LLSD::Real execution = 0.0;
            if (calls > 0)
            {
                execution = time/calls;
                cur_execution.push_back(execution);
                cur_times.push_back(time);
            }

            cur_calls.push_back(calls);
        }

        for (U32 i = 0; i < base_data.size(); ++i)
        {
            LLSD::Real time = base_data[i][label]["Time"].asReal();
            LLSD::Integer calls = base_data[i][label]["Calls"].asInteger();

            LLSD::Real execution = 0.0;
            if (calls > 0)
            {
                execution = time/calls;
                base_execution.push_back(execution);
                base_times.push_back(time);
            }

            base_calls.push_back(calls);
        }

        std::sort(base_calls.begin(), base_calls.end());
        std::sort(base_times.begin(), base_times.end());
        std::sort(base_execution.begin(), base_execution.end());

        std::sort(cur_calls.begin(), cur_calls.end());
        std::sort(cur_times.begin(), cur_times.end());
        std::sort(cur_execution.begin(), cur_execution.end());

        //remove outliers
        const U32 OUTLIER_CUTOFF = 512;
        if (base_times.size() > OUTLIER_CUTOFF)
        {
            ll_remove_outliers(base_times, 1.f);
        }

        if (base_execution.size() > OUTLIER_CUTOFF)
        {
            ll_remove_outliers(base_execution, 1.f);
        }

        if (cur_times.size() > OUTLIER_CUTOFF)
        {
            ll_remove_outliers(cur_times, 1.f);
        }

        if (cur_execution.size() > OUTLIER_CUTOFF)
        {
            ll_remove_outliers(cur_execution, 1.f);
        }


        max_time = llmax(base_times.empty() ? 0.0 : *base_times.rbegin(), cur_times.empty() ? 0.0 : *cur_times.rbegin());
        max_calls = llmax(base_calls.empty() ? 0 : *base_calls.rbegin(), cur_calls.empty() ? 0 : *cur_calls.rbegin());
        max_execution = llmax(base_execution.empty() ? 0.0 : *base_execution.rbegin(), cur_execution.empty() ? 0.0 : *cur_execution.rbegin());


        LLVector3 last_p;

        //====================================
        // basic
        //====================================
        buffer.clear();

        last_p.clear();

        LLGLDisable cull(GL_CULL_FACE);

        LLVector3 base_col(0, 0.7f, 0.f);
        LLVector3 cur_col(1.f, 0.f, 0.f);

        gGL.setSceneBlendType(LLRender::BT_ADD);

        gGL.color3fv(base_col.mV);
        for (U32 i = 0; i < base_times.size(); ++i)
        {
            gGL.begin(LLRender::TRIANGLE_STRIP);
            gGL.vertex3fv(last_p.mV);
            gGL.vertex3f(last_p.mV[0], 0.f, 0.f);
            last_p.set((F32)i/(F32) base_times.size(), base_times[i]/max_time, 0.f);
            gGL.vertex3fv(last_p.mV);
            gGL.vertex3f(last_p.mV[0], 0.f, 0.f);
            gGL.end();
        }

        gGL.flush();


        last_p.clear();
        {
            LLGLEnable blend(GL_BLEND);

            gGL.color3fv(cur_col.mV);
            for (U32 i = 0; i < cur_times.size(); ++i)
            {
                gGL.begin(LLRender::TRIANGLE_STRIP);
                gGL.vertex3f(last_p.mV[0], 0.f, 0.f);
                gGL.vertex3fv(last_p.mV);
                last_p.set((F32) i / (F32) cur_times.size(), cur_times[i]/max_time, 0.f);
                gGL.vertex3f(last_p.mV[0], 0.f, 0.f);
                gGL.vertex3fv(last_p.mV);
                gGL.end();
            }

            gGL.flush();
        }

        saveChart(label, "time", scratch);

        //======================================
        // calls
        //======================================
        buffer.clear();

        last_p.clear();

        gGL.color3fv(base_col.mV);
        for (U32 i = 0; i < base_calls.size(); ++i)
        {
            gGL.begin(LLRender::TRIANGLE_STRIP);
            gGL.vertex3fv(last_p.mV);
            gGL.vertex3f(last_p.mV[0], 0.f, 0.f);
            last_p.set((F32) i / (F32) base_calls.size(), (F32)base_calls[i]/max_calls, 0.f);
            gGL.vertex3fv(last_p.mV);
            gGL.vertex3f(last_p.mV[0], 0.f, 0.f);
            gGL.end();
        }

        gGL.flush();

        {
            LLGLEnable blend(GL_BLEND);
            gGL.color3fv(cur_col.mV);
            last_p.clear();

            for (U32 i = 0; i < cur_calls.size(); ++i)
            {
                gGL.begin(LLRender::TRIANGLE_STRIP);
                gGL.vertex3f(last_p.mV[0], 0.f, 0.f);
                gGL.vertex3fv(last_p.mV);
                last_p.set((F32) i / (F32) cur_calls.size(), (F32) cur_calls[i]/max_calls, 0.f);
                gGL.vertex3f(last_p.mV[0], 0.f, 0.f);
                gGL.vertex3fv(last_p.mV);
                gGL.end();

            }

            gGL.flush();
        }

        saveChart(label, "calls", scratch);

        //======================================
        // execution
        //======================================
        buffer.clear();

        gGL.color3fv(base_col.mV);
        U32 count = 0;
        U32 total_count = static_cast<U32>(base_execution.size());

        last_p.clear();

        for (std::vector<LLSD::Real>::iterator iter = base_execution.begin(); iter != base_execution.end(); ++iter)
        {
            gGL.begin(LLRender::TRIANGLE_STRIP);
            gGL.vertex3fv(last_p.mV);
            gGL.vertex3f(last_p.mV[0], 0.f, 0.f);
            last_p.set((F32)count/(F32)total_count, *iter/max_execution, 0.f);
            gGL.vertex3fv(last_p.mV);
            gGL.vertex3f(last_p.mV[0], 0.f, 0.f);
            gGL.end();
            count++;
        }

        last_p.clear();

        {
            LLGLEnable blend(GL_BLEND);
            gGL.color3fv(cur_col.mV);
            count = 0;
            total_count = static_cast<U32>(cur_execution.size());

            for (std::vector<LLSD::Real>::iterator iter = cur_execution.begin(); iter != cur_execution.end(); ++iter)
            {
                gGL.begin(LLRender::TRIANGLE_STRIP);
                gGL.vertex3f(last_p.mV[0], 0.f, 0.f);
                gGL.vertex3fv(last_p.mV);
                last_p.set((F32)count/(F32)total_count, *iter/max_execution, 0.f);
                gGL.vertex3f(last_p.mV[0], 0.f, 0.f);
                gGL.vertex3fv(last_p.mV);
                gGL.end();
                count++;
            }

            gGL.flush();
        }

        saveChart(label, "execution", scratch);
    }

    buffer.flush();

    gGL.popMatrix();
    gGL.matrixMode(LLRender::MM_MODELVIEW);
    gGL.popMatrix();
}

//static
LLSD LLFastTimerView::analyzePerformanceLogDefault(std::istream& is)
{
    LLSD ret;

    LLSD cur;

    LLSD::Real total_time = 0.0;
    LLSD::Integer total_frames = 0;

    typedef std::map<std::string,LLViewerStats::StatsAccumulator> stats_map_t;
    stats_map_t time_stats;
    stats_map_t sample_stats;

    while (!is.eof() && LLSDParser::PARSE_FAILURE != LLSDSerialize::fromXML(cur, is))
    {
        for (LLSD::map_iterator iter = cur.beginMap(); iter != cur.endMap(); ++iter)
        {
            std::string label = iter->first;

            F64 time = iter->second["Time"].asReal();

            // Skip the total figure
            if(label.compare("Total") != 0)
            {
                total_time += time;
            }

            if (time > 0.0)
            {
                LLSD::Integer samples = iter->second["Calls"].asInteger();

                time_stats[label].push(time);
                sample_stats[label].push(samples);
            }
        }
        total_frames++;
    }

    for(stats_map_t::iterator it = time_stats.begin(); it != time_stats.end(); ++it)
    {
        std::string label = it->first;
        ret[label]["TotalTime"] = time_stats[label].getSum();
        ret[label]["MeanTime"] = time_stats[label].getMean();
        ret[label]["MaxTime"] = time_stats[label].getMaxValue();
        ret[label]["MinTime"] = time_stats[label].getMinValue();
        ret[label]["StdDevTime"] = time_stats[label].getStdDev();

        ret[label]["Samples"] = sample_stats[label].getSum();
        ret[label]["MaxSamples"] = sample_stats[label].getMaxValue();
        ret[label]["MinSamples"] = sample_stats[label].getMinValue();
        ret[label]["StdDevSamples"] = sample_stats[label].getStdDev();

        ret[label]["Frames"] = (LLSD::Integer)time_stats[label].getCount();
    }

    ret["SessionTime"] = total_time;
    ret["FrameCount"] = total_frames;

    return ret;

}

//static
void LLFastTimerView::doAnalysisDefault(std::string baseline, std::string target, std::string output)
{
    // Open baseline and current target, exit if one is inexistent
    llifstream base_is(baseline.c_str());
    llifstream target_is(target.c_str());
    if (!base_is.is_open() || !target_is.is_open())
    {
        LL_WARNS() << "'-analyzeperformance' error : baseline or current target file inexistent" << LL_ENDL;
        base_is.close();
        target_is.close();
        return;
    }

    //analyze baseline
    LLSD base = analyzePerformanceLogDefault(base_is);
    base_is.close();

    //analyze current
    LLSD current = analyzePerformanceLogDefault(target_is);
    target_is.close();

    //output comparison
    llofstream os(output.c_str());

    LLSD::Real session_time = current["SessionTime"].asReal();
    os <<
        "Label, "
        "% Change, "
        "% of Session, "
        "Cur Min, "
        "Cur Max, "
        "Cur Mean/sample, "
        "Cur Mean/frame, "
        "Cur StdDev/frame, "
        "Cur Total, "
        "Cur Frames, "
        "Cur Samples, "
        "Base Min, "
        "Base Max, "
        "Base Mean/sample, "
        "Base Mean/frame, "
        "Base StdDev/frame, "
        "Base Total, "
        "Base Frames, "
        "Base Samples\n";

    for (LLSD::map_iterator iter = base.beginMap();  iter != base.endMap(); ++iter)
    {
        LLSD::String label = iter->first;

        if (current[label]["Samples"].asInteger() == 0 ||
            base[label]["Samples"].asInteger() == 0)
        {
            //cannot compare
            continue;
        }
        LLSD::Real a = base[label]["TotalTime"].asReal() / base[label]["Samples"].asReal();
        LLSD::Real b = current[label]["TotalTime"].asReal() / current[label]["Samples"].asReal();

        LLSD::Real diff = b-a;

        LLSD::Real perc = diff/a * 100;

        os << llformat("%s, %.2f, %.4f, %.4f, %.4f, %.4f, %.4f, %.4f, %.4f, %d, %d, %.4f, %.4f, %.4f, %.4f, %.4f, %.4f, %d, %d\n",
            label.c_str(),
            (F32) perc,
            (F32) (current[label]["TotalTime"].asReal()/session_time * 100.0),

            (F32) current[label]["MinTime"].asReal(),
            (F32) current[label]["MaxTime"].asReal(),
            (F32) b,
            (F32) current[label]["MeanTime"].asReal(),
            (F32) current[label]["StdDevTime"].asReal(),
            (F32) current[label]["TotalTime"].asReal(),
            current[label]["Frames"].asInteger(),
            current[label]["Samples"].asInteger(),
            (F32) base[label]["MinTime"].asReal(),
            (F32) base[label]["MaxTime"].asReal(),
            (F32) a,
            (F32) base[label]["MeanTime"].asReal(),
            (F32) base[label]["StdDevTime"].asReal(),
            (F32) base[label]["TotalTime"].asReal(),
            base[label]["Frames"].asInteger(),
            base[label]["Samples"].asInteger());
    }

    exportCharts(baseline, target);

    os.flush();
    os.close();
}

//static
void LLFastTimerView::outputAllMetrics()
{
    if (LLMetricPerformanceTesterBasic::hasMetricPerformanceTesters())
    {
        for (LLMetricPerformanceTesterBasic::name_tester_map_t::iterator iter = LLMetricPerformanceTesterBasic::sTesterMap.begin();
            iter != LLMetricPerformanceTesterBasic::sTesterMap.end(); ++iter)
        {
            LLMetricPerformanceTesterBasic* tester = ((LLMetricPerformanceTesterBasic*)iter->second);
            tester->outputTestResults();
        }
    }
}

//static
void LLFastTimerView::doAnalysis(std::string baseline, std::string target, std::string output)
{
    if(BlockTimer::sLog)
    {
        doAnalysisDefault(baseline, target, output) ;
        return ;
    }

    if(BlockTimer::sMetricLog)
    {
        LLMetricPerformanceTesterBasic::doAnalysisMetrics(baseline, target, output) ;
        return ;
    }
}


void LLFastTimerView::printLineStats()
{
    // Output stats for clicked bar to log
    if (mStatsIndex >= 0)
    {
        std::string legend_stat;
        bool first = true;
        for(LLTrace::block_timer_tree_df_iterator_t it = LLTrace::begin_block_timer_tree_df(FTM_FRAME);
            it != LLTrace::end_block_timer_tree_df();
            ++it)
        {
            BlockTimerStatHandle* idp = (*it);

            if (!first)
            {
                legend_stat += ", ";
            }
            first = false;
            legend_stat += idp->getName();

            //if (idp->getTreeNode().mCollapsed)
            //{
            //  it.skipDescendants();
            //}
        }
        LL_INFOS() << legend_stat << LL_ENDL;

        std::string timer_stat;
        first = true;
        for(LLTrace::block_timer_tree_df_iterator_t it = LLTrace::begin_block_timer_tree_df(FTM_FRAME);
            it != LLTrace::end_block_timer_tree_df();
            ++it)
        {
            BlockTimerStatHandle* idp = (*it);

            if (!first)
            {
                timer_stat += ", ";
            }
            first = false;

            F32Seconds ticks;
            if (mStatsIndex == 0)
            {
                ticks = mRecording.getPeriodMean(*idp, RUNNING_AVERAGE_WIDTH);
            }
            else
            {
                ticks = mRecording.getPrevRecording(mStatsIndex).getSum(*idp);
            }
            F32Milliseconds ms = ticks;

            timer_stat += llformat("%.1f",ms.value());

            //if (idp->getTreeNode().mCollapsed)
            //{
            //  it.skipDescendants();
            //}
        }
        LL_INFOS() << timer_stat << LL_ENDL;
        mStatsIndex = -1;
    }
}

void LLFastTimerView::drawLineGraph()
{
    LL_PROFILE_ZONE_SCOPED;
    //draw line graph history
    gGL.getTexUnit(0)->unbind(LLTexUnit::TT_TEXTURE);
    LLLocalClipRect clip(mGraphRect);

    //normalize based on last frame's maximum
    static F32Seconds max_time(0.000001);
    static U32 max_calls = 0;
    static F32 alpha_interp = 0.f;

    //highlight visible range
    {
        S32 first_frame = static_cast<S32>(mRecording.getNumRecordedPeriods()) - mScrollIndex;
        S32 last_frame = first_frame - MAX_VISIBLE_HISTORY;

        F32 frame_delta = ((F32) (mGraphRect.getWidth()))/(mRecording.getNumRecordedPeriods()-1);

        F32 right = (F32) mGraphRect.mLeft + frame_delta*first_frame;
        F32 left = (F32) mGraphRect.mLeft + frame_delta*last_frame;

        gGL.color4f(0.5f,0.5f,0.5f,0.3f);
        gl_rect_2d((S32) left, mGraphRect.mTop, (S32) right, mGraphRect.mBottom);

        if (mHoverBarIndex > 0)
        {
            S32 bar_frame = first_frame - (mScrollIndex + mHoverBarIndex) - 1;
            F32 bar = (F32) mGraphRect.mLeft + frame_delta*bar_frame;

            gGL.color4f(0.5f,0.5f,0.5f,1);

            gGL.begin(LLRender::LINES);
            gGL.vertex2i((S32)bar, mGraphRect.mBottom);
            gGL.vertex2i((S32)bar, mGraphRect.mTop);
            gGL.end();
        }
    }

    F32Seconds cur_max(0);
    U32 cur_max_calls = 0;

    for(LLTrace::block_timer_tree_df_iterator_t it = LLTrace::begin_block_timer_tree_df(FTM_FRAME);
        it != LLTrace::end_block_timer_tree_df();
        ++it)
    {
        BlockTimerStatHandle* idp = (*it);

        //fatten highlighted timer
        if (mHoverID == idp)
        {
            gGL.flush();
            glLineWidth(3);
        }

        llassert(idp->getIndex() < sTimerColors.size());
        const F32 * col = sTimerColors[idp->getIndex()].mV;// ft_display_table[idx].color->mV;

        F32 alpha = 1.f;
        bool is_hover_timer = true;

        if (mHoverID != NULL &&
            mHoverID != idp)
        {   //fade out non-highlighted timers
            if (idp->getParent() != mHoverID)
            {
                alpha = alpha_interp;
                is_hover_timer = false;
            }
        }

        gGL.color4f(col[0], col[1], col[2], alpha);
        gGL.begin(LLRender::TRIANGLE_STRIP);
        F32 call_scale_factor = (F32)mGraphRect.getHeight() / (F32)max_calls;
        F32 time_scale_factor = (F32)mGraphRect.getHeight() / max_time.value();
        F32 hz_scale_factor = (F32) mGraphRect.getHeight() / (1.f / max_time.value());

        for (U32 j = static_cast<U32>(mRecording.getNumRecordedPeriods());
            j > 0;
            j--)
        {
            LLTrace::Recording& recording = mRecording.getPrevRecording(j);
            F32Seconds time = llmax(recording.getSum(*idp), F64Seconds(0.000001));
            U32 calls = recording.getSum(idp->callCount());

            if (is_hover_timer)
            {
                //normalize to highlighted timer
                cur_max = llmax(cur_max, time);
                cur_max_calls = llmax(cur_max_calls, calls);
            }
            F32 x = mGraphRect.mRight - j * (F32)(mGraphRect.getWidth())/(mRecording.getNumRecordedPeriods()-1);
            F32 y = 0.0;
            switch(mDisplayType)
{
            case DISPLAY_TIME:
                y = mGraphRect.mBottom + time.value() * time_scale_factor;
                break;
            case DISPLAY_CALLS:
                y = mGraphRect.mBottom + (F32)calls * call_scale_factor;
                break;
            case DISPLAY_HZ:
                y = mGraphRect.mBottom + (1.f / time.value()) * hz_scale_factor;
                break;
            }
            gGL.vertex2f(x,y);
            gGL.vertex2f(x,mGraphRect.mBottom);
        }
        gGL.end();

        if (mHoverID == idp)
        {
            gGL.flush();
            glLineWidth(1);
        }

        if (idp->getTreeNode().mCollapsed)
        {
            //skip hidden timers
            it.skipDescendants();
        }
    }

    //interpolate towards new maximum
    max_time = (F32Seconds)lerp(max_time.value(), cur_max.value(), LLSmoothInterpolation::getInterpolant(0.1f));
    if (llabs((max_time - cur_max).value()) <= 1)
    {
        max_time = llmax(F32Microseconds(1.f), F32Microseconds(cur_max));
    }

    max_calls = ll_round(lerp((F32)max_calls, (F32) cur_max_calls, LLSmoothInterpolation::getInterpolant(0.1f)));
    if (llabs((S32)(max_calls - cur_max_calls)) <= 1)
    {
        max_calls = cur_max_calls;
    }

    // TODO: make sure alpha is correct in DisplayHz mode
    F32 alpha_target = (max_time > cur_max)
        ? llmin(max_time / cur_max - 1.f,1.f)
        : llmin(cur_max/ max_time - 1.f,1.f);
    alpha_interp = lerp(alpha_interp, alpha_target, LLSmoothInterpolation::getInterpolant(0.1f));

    if (mHoverID != NULL)
    {
        S32 x = (mGraphRect.mRight + mGraphRect.mLeft)/2;
        S32 y = mGraphRect.mBottom + 8;

        LLFontGL::getFontMonospace()->renderUTF8(
            mHoverID->getName(),
            0,
            x, y,
            LLColor4::white,
            LLFontGL::LEFT, LLFontGL::BOTTOM);
    }

    //display y-axis range
    std::string axis_label;
    switch(mDisplayType)
    {
    case DISPLAY_TIME:
        axis_label = llformat("%4.2f ms", F32Milliseconds(max_time).value());
        break;
    case DISPLAY_CALLS:
        axis_label = llformat("%d calls", (int)max_calls);
        break;
    case DISPLAY_HZ:
        axis_label = llformat("%4.2f Hz", max_time.value() ? 1.f / max_time.value() : 0.f);
        break;
    }

    LLFontGL* font = LLFontGL::getFontMonospace();
    S32 x = mGraphRect.mRight - font->getWidth(axis_label)-5;
    S32 y = mGraphRect.mTop - font->getLineHeight();;

    font->renderUTF8(axis_label, 0, x, y, LLColor4::white, LLFontGL::LEFT, LLFontGL::TOP);
}

void LLFastTimerView::drawLegend()
{
    // draw legend
    S32 dx;
    S32 x = mLegendRect.mLeft;
    S32 y = mLegendRect.mTop;
    const S32 TEXT_HEIGHT = (S32)LLFontGL::getFontMonospace()->getLineHeight();

    {
        LLLocalClipRect clip(mLegendRect);
        S32 cur_line = 0;
        S32 scroll_offset = 0; // element's y offset from top of the inner scroll's rect
        ft_display_idx.clear();
        std::map<BlockTimerStatHandle*, S32> display_line;
        for (LLTrace::block_timer_tree_df_iterator_t it = LLTrace::begin_block_timer_tree_df(FTM_FRAME);
            it != LLTrace::end_block_timer_tree_df();
            ++it)
        {
            BlockTimerStatHandle* idp = (*it);
            // Needed to figure out offsets and parenting
            display_line[idp] = cur_line;
            cur_line++;
            if (scroll_offset < mScrollBar->getDocPos())
            {
                // only offset for visible items
                scroll_offset += TEXT_HEIGHT + 2;
                if (idp->getTreeNode().mCollapsed)
                {
                    it.skipDescendants();
                }
                continue;
            }

            // used for mouse clicks
            ft_display_idx.push_back(idp);

            // Actual draw, first bar (square), then text
            x = MARGIN;

            LLRect bar_rect(x, y, x + TEXT_HEIGHT, y - TEXT_HEIGHT);
            S32 scale_offset = 0;
            if (idp == mHoverID)
            {
                scale_offset = llfloor(sinf(mHighlightTimer.getElapsedTimeF32() * 6.f) * 2.f);
            }
            bar_rect.stretch(scale_offset);
            llassert(idp->getIndex() < sTimerColors.size());
            gl_rect_2d(bar_rect, sTimerColors[idp->getIndex()]);

            F32Milliseconds ms(0);
            S32 calls = 0;
            if (mHoverBarIndex > 0 && mHoverID)
            {
                S32 hidx = mScrollIndex + mHoverBarIndex;
                ms = mRecording.getPrevRecording(hidx).getSum(*idp);
                calls = mRecording.getPrevRecording(hidx).getSum(idp->callCount());
            }
            else
            {
                ms = F64Seconds(mRecording.getPeriodMean(*idp, RUNNING_AVERAGE_WIDTH));
                calls = (S32)mRecording.getPeriodMean(idp->callCount(), RUNNING_AVERAGE_WIDTH);
            }

            std::string timer_label;
            switch(mDisplayType)
            {
            case DISPLAY_TIME:
                timer_label = llformat("%s [%.1f]",idp->getName().c_str(),ms.value());
                break;
            case DISPLAY_CALLS:
                timer_label = llformat("%s (%d)",idp->getName().c_str(),calls);
                break;
            case DISPLAY_HZ:
                timer_label = llformat("%.1f", ms.value() ? (1.f / ms.value()) : 0.f);
                break;
            }
            dx = (TEXT_HEIGHT+4) + get_depth(idp)*8;

            LLColor4 color = LLColor4::white;
            if (get_depth(idp) > 0)
            {
                S32 line_start_y = bar_rect.getCenterY();
                S32 line_end_y = line_start_y + ((TEXT_HEIGHT + 2) * (cur_line - display_line[idp->getParent()])) - TEXT_HEIGHT;
                gl_line_2d(x + dx - 8, line_start_y, x + dx, line_start_y, color);
                S32 line_x = x + (TEXT_HEIGHT + 4) + ((get_depth(idp) - 1) * 8);
                gl_line_2d(line_x, line_start_y, line_x, line_end_y, color);
                if (idp->getTreeNode().mCollapsed && !idp->getChildren().empty())
                {
                    gl_line_2d(line_x+4, line_start_y-3, line_x+4, line_start_y+4, color);
                }
            }

            x += dx;
            bool is_child_of_hover_item = (idp == mHoverID);
            BlockTimerStatHandle* next_parent = idp->getParent();
            while(!is_child_of_hover_item && next_parent)
            {
                is_child_of_hover_item = (mHoverID == next_parent);
                if (next_parent->getParent() == next_parent) break;
                next_parent = next_parent->getParent();
            }

            LLFontGL::getFontMonospace()->renderUTF8(timer_label, 0,
                x, y,
                color,
                LLFontGL::LEFT, LLFontGL::TOP,
                is_child_of_hover_item ? LLFontGL::BOLD : LLFontGL::NORMAL);

            y -= (TEXT_HEIGHT + 2);

            scroll_offset += TEXT_HEIGHT + 2;
            if (idp->getTreeNode().mCollapsed)
            {
                it.skipDescendants();
            }
        }
        // Recalculate scroll size
        mScrollBar->setDocSize(scroll_offset - mLegendRect.getHeight());
    }
}

void LLFastTimerView::generateUniqueColors()
{
    // generate unique colors
    {
        sTimerColors.resize(LLTrace::BlockTimerStatHandle::getNumIndices());
        sTimerColors[FTM_FRAME.getIndex()] = LLColor4::grey;

        F32 hue = 0.f;

        for (LLTrace::block_timer_tree_df_iterator_t it = LLTrace::begin_block_timer_tree_df(FTM_FRAME);
            it != LLTrace::end_block_timer_tree_df();
            ++it)
        {
            BlockTimerStatHandle* idp = (*it);

            const F32 HUE_INCREMENT = 0.23f;
            hue = fmodf(hue + HUE_INCREMENT, 1.f);
            // saturation increases with depth
            F32 saturation = clamp_rescale((F32)get_depth(idp), 0.f, 3.f, 0.f, 1.f);
            // lightness alternates with depth
            F32 lightness = get_depth(idp) % 2 ? 0.5f : 0.6f;

            LLColor4 child_color;
            child_color.setHSL(hue, saturation, lightness);

            llassert(idp->getIndex() < sTimerColors.size());
            sTimerColors[idp->getIndex()] = child_color;
        }
    }
}

void LLFastTimerView::drawHelp( S32 y )
{
    // Draw some help
    const S32 texth = (S32)LLFontGL::getFontMonospace()->getLineHeight();

    y -= (texth + 2);
    y -= (texth + 2);

    LLFontGL::getFontMonospace()->renderUTF8(std::string("[Right-Click log selected]"),
        0, MARGIN, y, LLColor4::white, LLFontGL::LEFT, LLFontGL::TOP);
}

void LLFastTimerView::drawTicks()
{
    // Draw MS ticks
    {
        U32Milliseconds ms = mTotalTimeDisplay;
        std::string tick_label;
        S32 x;
        S32 barw = mBarRect.getWidth();

        tick_label = llformat("%.1f ms |", (F32)ms.value()*.25f);
        x = mBarRect.mLeft + barw/4 - LLFontGL::getFontMonospace()->getWidth(tick_label);
        LLFontGL::getFontMonospace()->renderUTF8(tick_label, 0, x, mBarRect.mTop, LLColor4::white,
            LLFontGL::LEFT, LLFontGL::TOP);

        tick_label = llformat("%.1f ms |", (F32)ms.value()*.50f);
        x = mBarRect.mLeft + barw/2 - LLFontGL::getFontMonospace()->getWidth(tick_label);
        LLFontGL::getFontMonospace()->renderUTF8(tick_label, 0, x, mBarRect.mTop, LLColor4::white,
            LLFontGL::LEFT, LLFontGL::TOP);

        tick_label = llformat("%.1f ms |", (F32)ms.value()*.75f);
        x = mBarRect.mLeft + (barw*3)/4 - LLFontGL::getFontMonospace()->getWidth(tick_label);
        LLFontGL::getFontMonospace()->renderUTF8(tick_label, 0, x, mBarRect.mTop, LLColor4::white,
            LLFontGL::LEFT, LLFontGL::TOP);

        tick_label = llformat( "%d ms |", (U32)ms.value());
        x = mBarRect.mLeft + barw - LLFontGL::getFontMonospace()->getWidth(tick_label);
        LLFontGL::getFontMonospace()->renderUTF8(tick_label, 0, x, mBarRect.mTop, LLColor4::white,
            LLFontGL::LEFT, LLFontGL::TOP);
    }
}

void LLFastTimerView::drawBorders( S32 y, const S32 x_start, S32 bar_height, S32 dy )
{
    // Draw borders
    {
        S32 by = y + 6 + (S32)LLFontGL::getFontMonospace()->getLineHeight();

        //heading
        gl_rect_2d(x_start-5, by, getRect().getWidth()-5, y+5, LLColor4::grey, false);

        //tree view
        gl_rect_2d(5, by, x_start-10, 5, LLColor4::grey, false);

        by = y + 5;
        //average bar
        gl_rect_2d(x_start-5, by, getRect().getWidth()-5, by-bar_height-dy-5, LLColor4::grey, false);

        by -= bar_height*2+dy;

        //current frame bar
        gl_rect_2d(x_start-5, by, getRect().getWidth()-5, by-bar_height-dy-2, LLColor4::grey, false);

        by -= bar_height+dy+1;

        //history bars
        gl_rect_2d(x_start-5, by, getRect().getWidth()-5, LINE_GRAPH_HEIGHT-bar_height-dy-2, LLColor4::grey, false);

        by = LINE_GRAPH_HEIGHT-dy;

        //line graph
        //mGraphRect = LLRect(x_start-5, by, getRect().getWidth()-5, 5);

        gl_rect_2d(mGraphRect, false);
    }
}

void LLFastTimerView::updateTotalTime()
{
    switch(mDisplayMode)
    {
    case 0:
        mTotalTimeDisplay = mRecording.getPeriodMean(FTM_FRAME, RUNNING_AVERAGE_WIDTH)*2;
        break;
    case 1:
        mTotalTimeDisplay = mRecording.getPeriodMax(FTM_FRAME);
        break;
    case 2:
        // Calculate the max total ticks for the current history
        mTotalTimeDisplay = mRecording.getPeriodMax(FTM_FRAME, 20);
        break;
    default:
        mTotalTimeDisplay = F64Milliseconds(100);
        break;
    }

    mTotalTimeDisplay = LLUnits::Milliseconds::fromValue(llceil(mTotalTimeDisplay.valueInUnits<LLUnits::Milliseconds>() / 20.f) * 20.f);
}

void LLFastTimerView::drawBars()
{
    LL_PROFILE_ZONE_SCOPED;
    LLLocalClipRect clip(mBarRect);

    S32 bar_height = mBarRect.getHeight() / (MAX_VISIBLE_HISTORY + 2);
    const S32 vpad = llmax(1, bar_height / 4); // spacing between bars
    bar_height -= vpad;

    updateTotalTime();
    if (mTotalTimeDisplay <= (F32Seconds)0.0) return;

    drawTicks();
    const S32 bars_top = mBarRect.mTop - ((S32)LLFontGL::getFontMonospace()->getLineHeight() + 4);
    drawBorders(bars_top, mBarRect.mLeft, bar_height, vpad);

    // Draw bars for each history entry
    // Special: 0 = show running average
    LLPointer<LLUIImage> bar_image = LLUI::getUIImage("Rounded_Square");

    const S32 image_width = bar_image->getTextureWidth();
    const S32 image_height = bar_image->getTextureHeight();

    gGL.getTexUnit(0)->bind(bar_image->getImage());
    {
        const S32 histmax = (S32)mRecording.getNumRecordedPeriods();

        // update widths
        if (!mPauseHistory)
        {
            U32 bar_index = 0;
            if (!mAverageTimerRow.mBars)
            {
                mAverageTimerRow.mBars = new TimerBar[LLTrace::BlockTimerStatHandle::instance_tracker_t::instanceCount()];
            }
            updateTimerBarWidths(&FTM_FRAME, mAverageTimerRow, -1, bar_index);
            updateTimerBarOffsets(&FTM_FRAME, mAverageTimerRow);

            for (S32 history_index = 1; history_index <= histmax; history_index++)
            {
                llassert(history_index <= mTimerBarRows.size());
                TimerBarRow& row = mTimerBarRows[history_index - 1];
                bar_index = 0;
                if (!row.mBars)
                {
                    row.mBars = new TimerBar[LLTrace::BlockTimerStatHandle::instance_tracker_t::instanceCount()];
                    updateTimerBarWidths(&FTM_FRAME, row, history_index, bar_index);
                    updateTimerBarOffsets(&FTM_FRAME, row);
                }
            }
        }

        // draw bars
        LLRect frame_bar_rect;
        frame_bar_rect.setLeftTopAndSize(mBarRect.mLeft,
                                        bars_top,
                                        ll_round((mAverageTimerRow.mBars[0].mTotalTime / mTotalTimeDisplay) * mBarRect.getWidth()),
                                        bar_height);
        mAverageTimerRow.mTop = frame_bar_rect.mTop;
        mAverageTimerRow.mBottom = frame_bar_rect.mBottom;
        drawBar(frame_bar_rect, mAverageTimerRow, image_width, image_height);
        frame_bar_rect.translate(0, -(bar_height + vpad + bar_height));

        for(S32 bar_index = mScrollIndex; bar_index < llmin(histmax, mScrollIndex + MAX_VISIBLE_HISTORY); ++bar_index)
        {
            llassert(bar_index < mTimerBarRows.size());
            TimerBarRow& row = mTimerBarRows[bar_index];
            row.mTop = frame_bar_rect.mTop;
            row.mBottom = frame_bar_rect.mBottom;
            frame_bar_rect.mRight = frame_bar_rect.mLeft
                                    + ll_round((row.mBars[0].mTotalTime / mTotalTimeDisplay) * mBarRect.getWidth());
            drawBar(frame_bar_rect, row, image_width, image_height);

            frame_bar_rect.translate(0, -(bar_height + vpad));
        }

    }
    gGL.getTexUnit(0)->unbind(LLTexUnit::TT_TEXTURE);
}

F32Seconds LLFastTimerView::updateTimerBarWidths(LLTrace::BlockTimerStatHandle* time_block, TimerBarRow& row, S32 history_index, U32& bar_index)
{
    LL_PROFILE_ZONE_SCOPED;
    const F32Seconds self_time = history_index == -1
                                        ? mRecording.getPeriodMean(time_block->selfTime(), RUNNING_AVERAGE_WIDTH)
                                        : mRecording.getPrevRecording(history_index).getSum(time_block->selfTime());

    F32Seconds full_time = self_time;

    // reserve a spot for this bar to be rendered before its children
    // even though we don't know its size yet
    TimerBar& timer_bar = row.mBars[bar_index];
    bar_index++;

    for (BlockTimerStatHandle::child_iter it = time_block->beginChildren(), end_it = time_block->endChildren(); it != end_it; ++it)
    {
        full_time += updateTimerBarWidths(*it, row, history_index, bar_index);
    }

    timer_bar.mTotalTime  = full_time;
    timer_bar.mSelfTime   = self_time;
    timer_bar.mTimeBlock  = time_block;

    return full_time;
}

S32 LLFastTimerView::updateTimerBarOffsets(LLTrace::BlockTimerStatHandle* time_block, TimerBarRow& row, S32 timer_bar_index)
{
    LL_PROFILE_ZONE_SCOPED;

    TimerBar& timer_bar = row.mBars[timer_bar_index];
    const F32Seconds bar_time = timer_bar.mTotalTime - timer_bar.mSelfTime;
    timer_bar.mChildrenStart = timer_bar.mSelfStart + timer_bar.mSelfTime / 2;
    timer_bar.mChildrenEnd = timer_bar.mChildrenStart + timer_bar.mTotalTime - timer_bar.mSelfTime;

    if (timer_bar_index == 0)
    {
        timer_bar.mSelfStart = F32Seconds(0.f);
        timer_bar.mSelfEnd = bar_time;
    }

    //now loop through children and figure out portion of bar image covered by each bar, now that we know the
    //sum of all children
    F32 bar_fraction_start = 0.f;
    TimerBar* last_child_timer_bar = NULL;

    bool first_child = true;
    for (BlockTimerStatHandle::child_iter it = time_block->beginChildren(), end_it = time_block->endChildren();
        it != end_it;
        ++it)
    {
        timer_bar_index++;

        TimerBar& child_timer_bar = row.mBars[timer_bar_index];
        BlockTimerStatHandle* child_time_block = *it;

        if (last_child_timer_bar)
        {
            last_child_timer_bar->mLastChild = false;
        }
        child_timer_bar.mLastChild = true;
        last_child_timer_bar = &child_timer_bar;

        child_timer_bar.mFirstChild = first_child;
        if (first_child)
        {
            first_child = false;
        }

        child_timer_bar.mStartFraction = bar_fraction_start;
        child_timer_bar.mEndFraction = bar_time > (S32Seconds)0
                                        ? bar_fraction_start + child_timer_bar.mTotalTime / bar_time
                                        : 1.f;
        child_timer_bar.mSelfStart = timer_bar.mChildrenStart
                                    + child_timer_bar.mStartFraction
                                        * (timer_bar.mChildrenEnd - timer_bar.mChildrenStart);
        child_timer_bar.mSelfEnd =  timer_bar.mChildrenStart
                                    + child_timer_bar.mEndFraction
                                        * (timer_bar.mChildrenEnd - timer_bar.mChildrenStart);

        timer_bar_index = updateTimerBarOffsets(child_time_block, row, timer_bar_index);

        bar_fraction_start = child_timer_bar.mEndFraction;
    }
    return timer_bar_index;
}

S32 LLFastTimerView::drawBar(LLRect bar_rect, TimerBarRow& row, S32 image_width, S32 image_height, bool hovered, bool visible, S32 bar_index)
{
    LL_PROFILE_ZONE_SCOPED;
    TimerBar& timer_bar = row.mBars[bar_index];
    LLTrace::BlockTimerStatHandle* time_block = timer_bar.mTimeBlock;

    hovered |= mHoverID == time_block;

    // animate scale of bar when hovering over that particular timer
    if (visible && (F32)bar_rect.getWidth() * (timer_bar.mEndFraction - timer_bar.mStartFraction) > 2.f)
    {
        LLRect render_rect(bar_rect);
        S32 scale_offset = 0;
        if (mHoverID == time_block)
        {
            scale_offset = llfloor(sinf(mHighlightTimer.getElapsedTimeF32() * 6.f) * 3.f);
            render_rect.mTop += scale_offset;
            render_rect.mBottom -= scale_offset;
        }

        llassert(time_block->getIndex() < sTimerColors.size());
        LLColor4 color = sTimerColors[time_block->getIndex()];
        if (!hovered) color = lerp(color, LLColor4::grey, 0.2f);
        gGL.color4fv(color.mV);
        gl_segmented_rect_2d_fragment_tex(render_rect,
            image_width, image_height,
            16,
            timer_bar.mStartFraction, timer_bar.mEndFraction);
    }

    LLRect children_rect;
    children_rect.mLeft  = ll_round(timer_bar.mChildrenStart / mTotalTimeDisplay * (F32)mBarRect.getWidth()) + mBarRect.mLeft;
    children_rect.mRight = ll_round(timer_bar.mChildrenEnd   / mTotalTimeDisplay * (F32)mBarRect.getWidth()) + mBarRect.mLeft;

    if (bar_rect.getHeight() > MIN_BAR_HEIGHT)
    {
        // shrink as we go down a level
        children_rect.mTop = bar_rect.mTop - 1;
        children_rect.mBottom = bar_rect.mBottom + 1;
    }
    else
    {
        children_rect.mTop = bar_rect.mTop;
        children_rect.mBottom = bar_rect.mBottom;
    }

    bool children_visible = visible && !time_block->getTreeNode().mCollapsed;

    bar_index++;
    const auto num_bars = LLTrace::BlockTimerStatHandle::instance_tracker_t::instanceCount();
    if (bar_index < num_bars && row.mBars[bar_index].mFirstChild)
    {
        bool is_last = false;
        do
        {
            is_last = row.mBars[bar_index].mLastChild;
            bar_index = drawBar(children_rect, row, image_width, image_height, hovered, children_visible, bar_index);
        }
        while(!is_last && bar_index < num_bars);
    }

    return bar_index;
}