Line Merge

Bluebeam now enables the creation of line merged PDF files. An example of the resulting PDF with the Line Merge option selected is shown below:

By selecting Line Merge, solid colored lines will appear transparent when overlapping other colored lines. Likewise, text underneath shaded areas will be visible.

Blend Modes

There are a number of blend modes that can be used to control the line merge setting. Click Advanced to display the Advanced Conversion Settings, which can be used to select the desired blend mode settings:

There are a total of 12 blend modes which can be used for controlling the transparency settings with line merge enabled. The PDF Reference Manual, Table 7.3 describes the 12 modes in detail. The modes are summarized below:

• Normal: Selects the source color, ignoring the backdrop.
• Multiply: Multiplies the backdrop and source color values.
• Screen: Multiplies the complements of the backdrop and the source color values, then complements the result.
• Overlay: Multiplies or screens the colors, depending on the backdrop color.
• Darken (default): Selects the darker of the backdrop and source colors.
• Lighten: Selects the lighter of the backdrop and source colors.
• ColorDodge: Brightens the backdrop color to reflect the source color.
• ColorBurn: Darkens the backdrop color to reflect the source color.
• HardLight: Multiplies or screens the colors, depending on the source color.
• SoftLight: Darkens or lightens the colors, depending on the source color value.
• Difference: Subtracts the darker of the two constituent colors.

Note that some PDF readers (such as Acrobat prior to 6.0) may not display line-merged images correctly.