ci-server-engineer/.claude/skills/graphics/tasks/trend.md

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task: Configure a trend (chart) component; what each setting does on the desktop and in the HTML display version: R1.03 source: IM 36K10C50-01EN §2.27 (Trend, Tables 2.27-10…28), §2.29 (Micro Trend); IM 36K10R30-01EN §4.8.7; installed web client code (%TLS_WAP_PATH%\mobileoperator\src\fasttools\ui\components\implementation\charts\); practiced on CI-Eng-Sample (display CIENG_TrendLab) 2026-10-02 status: verified (desktop Operator Interface: every row marked ✅/❌ below; HTML display: §6)

Trend settings (desktop and web)

Example: examples/CI-Eng-Sample/displays/CIENG_TrendLab.xml (deployed by deploy_displays.cmd). Method used: change one XML value in the display, deploy, View > Reload in the client, compare.

1. Before you start

• Data: the trend draws history. TANK1.LEVEL / TANK1.INFLOW are internal items: after a CI Server start they are NOT INIT (value 0) until something writes them, and the trend then shows nothing (or a bold black line at 0 with status drawing). For tests run displays/trend_feed.ps1 (writes sine waves with itmval every 5 s; -Seconds = run time).
• Reload: changes in the display file show after View > Reload. A reload within a few seconds of the deploy can still show the old file — reload again.
• The Trend properties dialog (right-click the trend) and the trend toolbar change the trend only for the session; Save trend as writes a trend definition to %TLS_WAP_PATH%\cfg\charts\<name>.xml (same <chartPanel> format; factory Template1..4.xml). The display file holds the start-up settings under <chart> › <config> › <chartPanel>.

2. Pen source (<pen> › <source uri=…>)

ci:/item/<Section>.<Tag>[?historygroup=<GROUP>[&amp;aggregationperiod=<PERIOD>]][#<ATTR>]

Part	Values	Result (desktop and web the same)
no historygroup	—	works; trend picks the highest-priority storage group (here CIENG_SCAN10S, seen in table mode); legend without [group]
historygroup=CIENG_EVENT / CIENG_SCAN10S	an item storage group	works; legend … [GROUP]
aggregation group without attribute	e.g. CIENG_AGG	❌ WFL-E-HIS_ITMN / ITH-E-NO_ADM_UPD Item not defined in group, or group not specified
aggregation group with aggregationperiod + #MAX	periods 30MIN HOUR SHIFT DAY WEEK MONTH YEAR; attributes MAX MIN AVG INT SDV CNT DFSM	✅ one flat segment per finished period; legend … / AGG_MAX 30MIN [CIENG_AGG]
#H #HH #L #LL #DB	limit / deadband attributes	❌ Record not found unless the limit history is stored
uri=""	—	empty pen

& must be written & in the XML. The Pen attributes > Attribute[n] property of the component is the same attribute (ITEM_VALUE, AGG_MAX…): connecting it to an item by mistake gives Short attribute name () is invalid (ISS-041 history).

3. Pen settings (<pen>)

XML	Values	Desktop result
type	0/1 line, 2 bar (no button in the pen panel), 3 stair-step, 4 scatter (squares); +256 = status drawing: offline / NOT INIT parts drawn bold black (256 = Edit Module default = line + status)	✅
color, stroke width		✅
paint (fill) <paint type="paint"><paint type="colorSet" …/></paint>		✅ filled from 0 up, opaque (covers other pens); legend symbol filled
visible false		✅ line hidden and removed from legend; tick cleared in the pen panel
visibleLegend false / legendText		✅ hidden from / renamed in the legend
scaleRangeType	0 item scale range (item definition), 1 manual minimum/maximum, 2 fit to data (with margin; min/max ignored)	✅
procentual		✅ axis 0–100 % of the range, % label
timeShift	seconds	✅ data drawn later by that time (overlay of older data)
axisVisible		✅ value axis (left); clicking a legend entry also shows that pen's axis and thickens the line (hover thickens)
axisPosition	0 left, 1 right	✅
axisColor, labelColor (<axisColor type="colorSet" r=… g=… b=…/>, @NULL = pen colour)		✅ axis + ticks / numbers
labelRotation	degrees	✅
majorTickVisible + minorTickVisible false		removes the numbers too
title, titlePlacement		❌ nothing shown
majorGridVisible, minorGridVisible, majorGridColor		✅ horizontal grid in pen colour / given colour
lowHighLimitGridVisible, lowLowHighHighLimitGridVisible		✅ lines at the item definition limits
lowLimit…highHighLimit		❌ ignored (item definition limits are used)
lowHighLimitGridAreaVisible		✅ band L…H in pen colour, opaque, drawn over the line
maximumPens (chart level)		✅ only the first n pens are loaded
description		pen panel shows the item description, not this value

4. Chart settings (<chartPanel>)

Group	XML	Desktop result
Time range	<timeRange type="timeRangeLast" count="10"><type type="timeUnit" value="TimeUnitMinute"/></timeRange>; timeRangeCurrent (no count) = current minute/hour/day…; units TimeUnitMinute Hour Day Week Month Year	✅ (Current hour: 12:00–13:00, line up to now)
	updating true	✅ runs live when opened (play grey, stop red)
	updateInterval (s)	✅ shown in Update every (60 → "1 Minutes")
	autoUpdateInterval true	✅ the Update every field disappears
	fillHistory false	✅ empty (all pens red tag) until the first update interval, then filled
	custom range timeRangeSpecific (startTime/endTime)	not tested
Performance	optimised true (default) = sample interval by zoom (cfg\configurations\ChartThresholdTables.xml)	—
	optimised false + useSampleInterval true + sampleInterval 60	✅ one point per 60 s, last value held to now
	useSampleInterval false	✅ all stored samples
	updateFromHistory false (runtime values)	no visible difference
Appearance	plotAreaTransparent false + plotAreaPaint	✅ plot colour (paint has no effect while transparent)
	backgroundPaint	❌ no visible effect
	hairlineVisible, hairlineColor	✅ toolbar hairline button on; click in the plot → line + box with time and pen values
	timeSliderVisible, valueSliderVisible false	✅ sliders removed
	xAxisReversed / yAxisReversed	✅ newest left and time axis moves to the top / 0 at top and value axis moves right
	renderMode Rendering2d, RenderingTable, Rendering3dObl (Rendering3dOrt, RenderingCSS not tested)	✅ table = sample time, value and status per pen (good to see what the server returns); 3D = hatched ribbons
Time axis	timeAxisMajorGridColor, timeAxisLabelRotation, timeAxisTitle	✅ (the time-axis title shows, unlike the pen title)
	timeAxisLongLabelVisible false	✅ date line under the first label removed
	timeAxisMinorTickVisible, timeAxisMinorGridVisible	nothing at a 10-minute range
Header/footer	headerText, footerText	✅ top-left above the plot / bottom-left below the time control
Legend	legendPositionType PositionNorthEast (default, right panel), PositionSouthWest (= full-height panel on the left); also NorthBottom NorthTop NorthWest SouthBottom SouthTop SouthEast East Absolute	✅
	legendTitle, legendColor, legendBackgroundColor, legendTransparancy	✅
Controls	toolbarVisible false, timeRangeControlVisible false	✅ toolbar / date and range boxes removed
Pen panel	penPanelVisible; penPanelLayout columns: 0 visible, 1 colour, 2 source, 3 description, 4 units, 5 hairline value, 6 statistics (min | max | avg of the shown range), 7 legend, 8 min, 9 max, 10 %, 11 scale range, 12 time offset, 13 appearance, 14 axis, 15 grid (default visible 0–4, 8, 9, 11, 13)	✅

Gaps (CI Server stopped): the desktop joined the last and next sample with a straight line, or held a scan-group pen flat (seen once); the web drops to 0.

5. Component property sheet (Edit Module, connectable)

20 pen slots [00]–[19]. Inputs (⇦, item → trend): colours, tooltip, visible, transparency, rotation, zoom. Outputs (⇨): Hairline value[n], Time range begin/end, Update interval, Updating possible. Both (◇): Item name[n], Attribute[n], Color[n], Min/Max[n], Scale type[n], History group[n], Updating, Use history, Item index/name, Configuration file. Connections were listed, not tested.

6. HTML display (web client)

• A trend with fewer than 50 visible pens with an item draws no line in R1.03 (ISS-041): the web code always builds 50 data columns (PEN_COUNT_LIMIT) but labels only the visible pens with an item; console Mismatch between number of labels (…) and number of columns in array (51). The desktop is not affected.
• Workaround (verified 2026-10-02): pad the trend to 50 pens with displays/add_trend_spares.ps1 -Path <display>.xml. Spares copy the first pen's source, are scaled to 1E30–2E30 (clipped), hidden from the legend and get blank unique legend texts in the legend background colour (the web legend ignores Show in legend, ISS-056). Run it again after editing the trend; do not keep hidden real pens: one hidden real pen (49 visible) and nothing draws again (checked). Cost: 50 history requests per trend.
• Web check of the settings (2026-10-02, padded scratch copy of CIENG_TrendLab, checked in the browser; supported-property lists: IM 36K10C50 Table 2.27-28, IM 36K10R30 §4.8.7):

  Works as on the desktop	Ignored on the web	Different on the web
  pen type line / stair-step / scatter, stroke, fill paint, legendText, scale range 0/1/2 (item, manual, fit), axisVisible, axisColor, labelColor; last / current time range, updateInterval, autoUpdateInterval (field hidden), updating true/false, fixed sample interval, timeRangeControlVisible; plotAreaTransparent + plotAreaPaint, header, footer, time-axis grid colour, time-axis label rotation, timeAxisLongLabelVisible, legendVisible, legend text and background colour	pen labelRotation, axisPosition (axis stays left), procentual, major/minor grid, limit lines; timeAxisTitle, legend position and title, pen panel, trend toolbar (no way to add pens in the browser), xAxisReversed, render mode (always 2D), Show in legend (ISS-056)	timeShift: data shifted, then message Illegal start/end time specification. Hairline: shown on hover (not click), box with time, value and status of the nearest pen only. Only one value axis is drawn; pens without an axis are plotted as % of their own range against it (misleading). Gaps (CI Server down) drop to 0.

• Micro Trend (<microTrend>, up to 4 pens, own SVG drawing, no controls; per-pen <property type="componentProperty"><name>itemName[0]</name><value>…</value></property>, scaleMin[n], scaleMax[n]; elements numberOfPens, realTime, fillWithHistory, timeRange (s, default 300), sampleCount (default 300)): drew on desktop and web the first time, then stayed blank on several later opens (ISS-055). Cause: Number of pens resets all pen sources, so fixed item names can be lost during load. Connect microTrend.itemName[n] to the item with attribute ItemName instead (<action type="actionConnectTo">, <direction>1, <itemAttribute>ItemName; sample CIENG_TrendLab): both pens then drew on every open; the history fill still failed once in three opens (only the live part drew; ISS-055 open).