Raster Transparency Setter (Selected Layers)

A QGIS plugin that lets you quickly set the transparency (opacity) of all selected raster layers at once.

Instead of changing opacity one layer at a time, you simply select multiple raster layers in the Layers Panel, run the tool, and apply a percentage-based transparency to all of them in a single step.

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Features

• Works on selected layers in the QGIS Layers Panel.
• Automatically filters and applies changes only to raster layers.
• Ignores non-raster layers (vectors, groups, etc.).
• Simple dialog to set transparency between 0–100%.
• Instant map refresh using layer.triggerRepaint().

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Installation

1. Download or clone this repository.

2. Copy the plugin folder into your QGIS user plugins directory:

   • Windows
     C:\Users\<USERNAME>\AppData\Roaming\QGIS\QGIS3\profiles\default\python\plugins\

   • Linux
     ~/.local/share/QGIS/QGIS3\profiles\default\python\plugins\

   • macOS
     ~/Library/Application Support/QGIS/QGIS3/profiles/default/python/plugins/

3. Restart QGIS.

4. Go to Plugins → Manage and Install Plugins…

5. In the Installed tab, find RasterTransparencySetter and check it to enable.

   Usage

   1.Prepare your Data -Select multiple raster Layers. -Non-raster Layers (vector layers,groups etc ) wil be ignored.

   2.Run the Plugin

   • From the menu: Raster Tools → Set Raster Transparency (Selected Layers)
   • Or click the plugin toolbar icon

   3.Set Transparency

   • A dialog box will appear asking:

   Enter transparency (0–100%):

   • Enter a value between 0% (fully opaque) and 100% (fully transparent).
   • Click OK to apply the transparency to all selected raster layers.
   • Click Cancel if you do not want to make any changes.

   4.View Changes

   • All selected raster layers will update immediately.
   • The map canvas refreshes automatically with the new opacity values.

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Messages & Error Handling

The plugin uses QMessageBox to show feedback direcctly in Qgis :

-Info Messages:

• If no layers are seleceted in the Layers Panel:
• “Please select one or more layers first.” -If none of the selected layers are raster layers: -“Please select one or more layers first.”

-Input Dialog: -Uses 'QInputDialog.getInt' to request a ytreansparency value between 0-100%. -If the user click Cancel*, no changes are applied

• Rendering update:
  • After updating opacity, each raster layer is refreshed with:

    layer.triggerRepaint()

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Limitations & Notes

• The plugin currently supports:
• Only raster layers (QgsRasterLayer).
• Any non-raster layers in the selection are ignored.

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License

This plugin is released under the GPL-3.0 license.

Support and Contribution

• Homepage: [https://github.com/Consortis-Geospatial],(https://github.com/Consortis-Geospatial)
• Author: Dimitra Pappa -Consortis Geospatial
• email: pappa@consortis.gr
• Repository: [https://github.com/Consortis-Geospatial/RasterTransparencySetter],(https://github.com/Consortis-Geospatial/RasterTransparencySetter)
• Issues Tracker: [https://github.com/Consortis-Geospatial/RasterTransparencySetter/issues],(https://github.com/Consortis-Geospatial/RasterTransparencySetter/issues)