SWMM5 Delphi GUI Dpattern.pas Summary

 Below is an overview of Dpattern.pas, a Delphi unit from SWMM 5.2 that provides a dialog (TPatternForm) to create or edit time patterns in SWMM. These time patterns (monthly, daily, or hourly) are typically used to modify inflow or pollutant concentrations on a varying schedule.

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1. Purpose and Context

SWMM supports time patterns to represent how certain parameters (e.g., DWF inflow, treatment removal efficiencies, etc.) vary over months, days, or hours. The TPatternForm dialog lets users enter the name and type of a pattern and specify its multiplier values in a grid. These multipliers scale a base value by a time-dependent factor.

A time pattern has:

• Pattern Type:

  1. Monthly (12 multipliers, one per month)
  2. Daily (7 multipliers, one per day of week)
  3. Hourly (24 multipliers, one per hour of the day)

• Name: A unique identifier for the pattern.

• Comment: An optional description (e.g., “Summer irrigation pattern”).

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2. Main Form: TPatternForm

2.1 Visual Components

1. NameEdit (TNumEdit): A field to set or edit the pattern's ID/name.
2. CommentEdit (TEdit): A single-line text field for an optional comment/description.
3. PatternTypeCombo (TComboBox): A dropdown to pick the pattern type (Monthly, Daily, Hourly).
4. GridEdit1 (TGridEditFrame):
   • Houses a TStringGrid to display two columns:
     • Label column (month names, day names, or hour labels).
     • Multiplier column (where the user enters numeric multipliers).
5. OK/Cancel/Help Buttons.
6. EditBtn (TBitBtn): Launches a more comprehensive text editor for the comment if desired (via Uedit.EditComment).

2.2 Variables and Constants

• PatternIndex: The index of the pattern in SWMM’s project data (or -1 if new).
• MonthlyLabels, DailyLabels, HourlyLabels: Arrays of strings used to label the grid's first column.
• AM, PM: Additional strings for labeling hours in 12-hour format.

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3. Data Flow

3.1 SetData

1. Takes an Index (the pattern’s position in Project.Lists[PATTERN]) and a TPattern object (aPattern).
2. If the index >= 0, loads the pattern's name from Project.Lists[PATTERN].Strings[Index] into NameEdit.
3. Sets PatternTypeCombo.ItemIndex := aPattern.PatternType, which triggers PatternTypeComboClick.
4. Copies the comment (aPattern.Comment) into CommentEdit.
5. Copies the multipliers from aPattern.Data[] into the second column of GridEdit1.Grid.

3.2 PatternTypeComboClick

• Adjusts the GridEdit1.Grid.RowCount and the first column’s labels depending on the selected pattern type:
  • 12 rows for Monthly (Jan…Dec).
  • 7 rows for Daily (Sun…Sat).
  • 24 rows for Hourly (12 AM…11 PM).
• Ensures any empty multiplier cells are set to "1.0".

3.3 GetData

1. Outputs the pattern's Name (NameEdit.Text) to the calling variable S.
2. Writes PatternTypeCombo.ItemIndex to aPattern.PatternType.
3. Writes CommentEdit.Text to aPattern.Comment.
4. Reads each row of GridEdit1.Grid.Cells[1, row] into aPattern.Data[row].

3.4 OKBtnClick and ValidateData

• ValidateData checks:
  1. If NameEdit.Text is non-empty.
  2. If the name is unique (i.e., not used by another pattern).
  3. If all multiplier cells parse as valid floats.
• If valid, ModalResult := mrOK, otherwise an error message is shown.

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4. Additional Details

1. NameEditKeyPress: Blocks [ from being the first character.
2. EditBtnClick: Opens a comment editor for multiline/extended text.
3. HelpBtnClick: Launches the SWMM help topic for patterns.
4. The grid uses two columns: The first for a descriptive label (not editable), and the second for the multiplier.

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5. Typical Usage

1. The user picks an existing pattern from a SWMM interface and chooses Edit (or Add for a new one).
2. SetData populates TPatternForm with the pattern’s type, name, comment, and multipliers.
3. The user modifies the type or modifies the multipliers in GridEdit1.
4. On OK, ValidateData ensures the pattern is valid.
5. GetData finalizes changes back into SWMM’s Project.Lists[PATTERN][Index].

This approach seamlessly manages the variety of pattern types (monthly, daily, hourly) and ensures the user has a convenient, tabular way to enter multipliers while giving them a textual comment field for extra context.