gbLayout - Online Help

This page provides the latest online Help information for gbLayout. gbLayout provides an extremely easy-to-use method of optimizing the placement of items into a defined area. 2D and 3D visualization of the results are supported.

Overview	Toolbars	Parts List
Parts Library	Layout/Border Size	Part Placement
2D Image	3D Image	Results Summary

A special Multi-Chip Module (MCM) Edition of gbLayout is also available. The MCM-specific features of gbLayout are covered here.

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Overview

gbLayout consists of a single screen on which the list of items (parts) is defined and the placement results are displayed. Operation generally takes places in two modes. 2D mode is used for entering parts and generating a parts placement. 3D mode is used to view the resulting parts placement as a 3D image.

On the left of the screen is where user inputs are made, where the parts library is listed, and where the text summary of the placement results are shown. These controls can be removed to provide more space to display the layout images.

On the right of the screen is where the layout images are shown.

Here are images of gbLayout in its 2D and 3D modes of operation. The part list is created and placement completed in 2D mode (left image). The 3D image is viewed in 3D mode (right image).

Note that the lower toolbar contains buttons specific to the current mode.

The various controls on the left side of the screen can be hidden to provide more room to display the 2D and 3D images, as these screen shots show:

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Toolbars

All features are provided via two toolbars. The top toolbar provides general file management features. The second toolbar provides 2D and 3D display control. Content of the second toolbar varies, depending on the mode selected.

Here is the top toolbar and a description of each button. This toolbar is displayed at all times.

New	Create a new design file
Open	Open an existing design file
Save	Save current design to currently opened file
Save As	Save current design to user-specified file
Copy	Copy 2D/3D image to clipboard
Export	Save design to specified file format (STL, DXF)
Controls	Display information controls (parts list, library, results)
3D	Display 3D toolbar
Update	Check for online update
Email	Send email to gbLayout author
Help	Open browser to gbLayout Online Help page

Here is the bottom toolbar and a description of each button. This is the default content of the lower toolbar, corresponding to 2D mode of operation.

Std	Perform placement with parts ordered as specified in parts list
Sort	Sort items by size, then perform placement
Rnd	Randomly sort items, then perform placement
Opt	Randomly sort itmes, but perform placement over a all h/w combinations
Stop	Stop placement iterations
Gap	Fill layout gaps
Rot	Allow part rotation when filling gaps
Index	Display part index
Keepout	Display keepouts
Border	Display border
2D	Select colors (border,parts,keepout,text,background)
Auto	Sort items by size, then perform placement
Zoom+	Randomly sort items, then perform placement
Zoom-	Randomly sort itmes, but perform placement over a all h/w combinations
Reset	Stop placement iterations
Keepout	Modify keepout for all parts

Here is the bottom toolbar and a description of each button. This is the 3D content of the lower toolbar, corresponding to 3D mode of operation. This toolbar is shown when the "3D" button on the top toolbar is pressed.

Rotate	Automatically rotate image
X	Allow rotation about X axis
Y	Allow rotation about Y axis
Z	Allow rotation about Z axis
Reset	Return to starting position
Step	Single rotation
Grad	Display in blue-to-red colors according to z position
Mono	Display in single color
Std	Display using part library colors
3D	Select colors (lines, triangles, floor, background)
Line	Display/remove lines

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Parts List

To use gbLayout, a parts list must first be defined. There are several ways in which a part may be added to the parts list for the current design.

Libary Parts
To add a part from the library, simply double-click on a part from the parts library listing (see next paragraph) to add that part to the design parts list. Double-clicking adds a new part to the top of the parts list (see line 1 in the image to the left).

You can also manually type in the name of the library part.

To make it easier to enter multiple parts, you can follow the name of the parts with a quantity (see line 2 in the image to the left).

Non-Library Parts
To add a part not found in the parts library, simply type in the xy size of the part, followed by its quantity and description. The description must be preceded by a apostrophe (see line 3 in the example to the left).

For purposes of generating a 3D image, an optional part color may also be specified. Place the color name before the part name, preceded by an apostrophe (see line 4 in the example to the left).

A more complete description of a non-library part can also be entered by entering the following part properties on a single line - x, y, qty, xkeepout, ykeepout, z, description (see line 5 in the example to the left).

See the Parts Library discussion below for a listing and description of all supported part properties.

As before, an optional color name may also be specified with a part (see line 6 in the example to the left).

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Parts Library

The parts library used by gbLayout is simply a text file ("parts.txt"), with one line per part containing the following the following information. Separate part properties with a comma.

Here's a description of the properties for each part in the library.

Description	text description, used for finding a part within the part library (20 character limit)
x	left-right width of the part
y	top-bottom dimension of the part
z	thickness of the part (extending out of the screen)
xKeepout	area unavailable for parts placement on both left and right sides of the part
yKeepout	area unavailable for parts placement at the top and bottom of the part
Color	Color used to display the part (color name or hexadecimal format)

To edit the parts library, click on the "Parts Library" label to open the file in Notepad. Make any changes/additions required and then save the file.

Lines which begin with an apostrophe are ignored.

You must restart gbLayout for the changes to be reflected in the Parts Library list of gbLayout.

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User Inputs - Layout/Border Size

The placement routines require that the user specify the allowable size of the layout area. The size can be specified in two ways - as a maximum width (variable height) or as a fixed height/width. The "Max Size" textbox is used to enter both options.

To fix the width of the layout area, enter a Max Size like this, where a single dimension is entered:

To fix both the width and height of the layout area, enter a Max Size like this, where both the width and height are given, separated by an "x".

   400x400

If both the width and height are fixed, the layout area will be drawn to match the fixed dimensions - even if the parts will not fit into the specified dimensions. The parts will be shown, even if they lap over the layout border

The border size is specified by entering a single value into the "Border" textbox. The value entered is used on all four sides of the layout:

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Results

Once a placement has been completed properties of the layout and a list of parts is placed in the "Results" textbox.

Layout properties with and without the border are provided.

The list of parts is shown in the order in which they appear in the layout, along with the index number that is (optionally) displayed in the layout.

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Layout Display (2D)

Once a placement has been completed, a drawing of the part is shown, along with the border as specified by the user.

The borders are drawn around the layout, enclosing the area needed to place the parts.

The width of the border may be specified, plus it may be filled or unfilled, as specified by the user.

Within the layout drawing, display of the part index and keepout zones is optional.

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Part Placement

Several different placement options are available within gbLayout. The order of parts can be specified (as entered in the parts list), the parts can be sorted by size, the size of the layout area can be fixed, the aspect ratio of the resulting layout area can be constrained, and multiple placement iterations can be performed to search for the most efficient layout.

Once the order of parts has been specified (more on that below), the first part in the parts list is placed in the top/left of the layout area. Parts are then placed left-to-right, until the maximum specified width (x-dimension) is reached/exceeded. Then placement continues starting at the left edge below the lowest point (including keepout) of the previous line of parts.

Placement continues left-to-right, moving downward (y-dimension) until all parts are placed.

When the next part to be placed will not fit on the current row (too wide, thus leaving a gap), the user has the option to direct gbLayout to attempt to fill the gap with the next available part whose width does not exceed the gap, provided that the part does not extend below the lowest point of the current line of parts.

Additionally, the user has the option to rotate parts (90 degrees clockwise) in order to fill the gap. A rotated part will be used to fill the gap if it does not extend below the lowest point of the current line of parts.

Both the gap filling and part rotation capabilities are optional and may be set using the appropriate toolbar buttons.

There are five toolbar buttons available for selecting the available placement options.

Std	Place the parts in the order in which they are entered into the Parts textbox.
Sort	Sort the parts by width before performing placement
Rnd	Randomly order the parts before performing placement
Opt	Randomly order the parts + vary the layout area dimensions
Stop	Stop any placement iteration in progress

In the case of #3 and #4, the random ordering of parts may also include random rotation of the parts.

Part Placement Iterations
In additional to performing a single placement of parts, gbLayout allows the user to perform up to one thousand placements - then display the placement that resulted in the least required layout area. Two different placement iteration approaches are provided:

Fixed Layout Size
Use the existing layout size for all iterations
Variable Layout Size
Vary the layout size - from all parts aligned vertically (the width of the widest component) to all parts aligned horizontally in the layout.

Setting Iteration Options
The number of placement iterations performed and the maximum aspect ratio of the resulting layout can be specified by the user.

The down arrow next to the Rnd toolbar button is used to select the number of iterations.

The down arrow next to the Opt toolbar button is used to select the maximum aspect ratio the user want to evaluate.

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Layout Display - 3D

The 2D layout can be converted to a 3D display pressing the 3D toolbar option. This displays a third toolbar which provides several options for manipulating the 3D image. The 3D image can be automatically rotated or resized. The lines that frame the triangles of the images can be removed. Display colors can also be selected.

Here's an example of a 3D image of a layout.

And here is the 3D toolbar that is added (repeat of information provided above):

Rotate	Automatically rotate image
X	Allow rotation about X axis
Y	Allow rotation about Y axis
Z	Allow rotation about Z axis
Reset	Return to starting position
Step	Single rotation
Grad	Display in blue-to-red colors according to z position
Mono	Display in single color
Std	Display using part library colors
3D	Select colors (lines, triangles, floor, background)
Line	Display/remove lines