TurboControls LCL Library

Copyright (c) 2025-2026 Turborium
github.com/turborium/TurboControls
Telegram: @turborium

TurboControls is a LCL component library providing UI controls for Lazarus/Free Pascal.
At the moment, the library mainly contains controls for working with color.
The package does not use any non-standard units, only standard LCL/FPC units.
All components work correctly with High-DPI and have full support for input focus.

License

You can choose one of two licenses:

• Turborium Modified MIT License
• GPL v3

See LICENSE.txt for the full license text of the Turborium Modified MIT License.

Users may obtain a commercial version of this software without the requirement to display the "About" notice in their application. Such commercial license is available directly from Turborium under separate terms and conditions.

Overview

• Linear pickers (horizontal/vertical) for single components: HSL, HSV, RGB, Alpha.
• 2D axis pickers for selecting two components at once (for example: Hue * Saturation or Red * Green).
• A color cell control for showing or picking a single color with alpha preview support.

Installation

Quick steps to install and use TurboControls in Lazarus:

• Open TurboControlsPackage.lpk in Lazarus.
• Click Compile button in "Package" window.
• Click Use->Install button.
• Choose "Yes" button in "Rebuild Lazarus" dialog.
• Wait...
• Done.

After installation, the components will appear in the TurboControls palette group.

Samples

ColorControls sample - This sample demonstrates TurboControls color picker components and how they work together.

Controls

TTurboColorCell

A visual color cell that displays a color (with alpha preview). Can be used as an interactive color swatch for display or selection.

Main properties:

• Value: The displayed color value.
• AlphaPreview: Alpha preview opacity used when rendering transparency preview.
• Background: Appearance settings for checkerboard/transparent settings.
• Interactive: Enable interactive behavior (responds to clicks and focus); when enabled the control can act as a clickable color swatch.
• Selected: Visual selection state; used by container controls or selection logic to indicate the cell is selected.
• Selection: Appearance settings for the selection frame (colors, opacity and pressed/hover states).

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TTurboAlphaLinePicker

A linear picker for the alpha channel (0..255) with transparent background preview.

Main properties:

• Alpha: Alpha value controlled by the picker (0..255).
• Min: Minimum value of the picker range.
• Max: Maximum value of the picker range.
• Reverse: Invert the value-to-position mapping.
• ColorPreview: Base color used when previewing alpha.
• ColorModulation: Enable color modulation in the range preview.
• RangeBackground: Appearance settings for checkerboard/transparent settings.
• PreviewStyle: Preview visualization style (gradient/lines) without color modulation.
• Orientation: Control orientation (Horizontal, Vertical).
• Layout: Visual arrangement of the thumb(s) and arrows (ExternalArrows, InternalArrows, CenterArrows, OverlapBox, InsideBox).
• ThumbLayout: Which thumbs are visible (First, Second, Both).
• ThumbSize: Thumb size settings (Width/Height or Auto).
• PositionLineVisible: Show a position indicator line on the range.
• ForceRepaint: Force immediate repaint when the picker or its range changes.

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TTurboRgbLinePicker

A linear RGB picker used to edit a single channel (Red, Green, Blue).

Main properties:

• Red, Green, Blue: Channel values (0..255) shown/edited by the picker.
• Kind: Selected channel (Red, Green, Blue).
• Min: Minimum value of the picker range.
• Max: Maximum value of the picker range.
• Reverse: Invert the value-to-position mapping.
• CurrentColor: Helper property to get/set the combined RGB color.
• ColorModulation: Enable color modulation in the range preview.
• AlphaPreview: Alpha preview opacity used in range rendering.
• RangeBackground: Appearance settings for checkerboard/transparent settings.
• PreviewStyle: Preview visualization style (gradient/lines) without color modulation.
• Orientation: Control orientation (Horizontal, Vertical).
• Layout: Visual arrangement of the thumb(s) and arrows (ExternalArrows, InternalArrows, CenterArrows, OverlapBox, InsideBox).
• ThumbLayout: Which thumbs are visible (First, Second, Both).
• ThumbSize: Thumb size settings (Width/Height or Auto).
• PositionLineVisible: Show a position indicator line on the range.
• ForceRepaint: Force immediate repaint when the picker or its range changes.

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TTurboRgbAxisPicker

A 2D RGB axis picker for selecting two color channels at once (for example: Red * Green).

Main properties:

• HorizontalKind: Which channel maps to the horizontal axis (Red, Green, Blue).
• VerticalKind: Which channel maps to the vertical axis (Red, Green, Blue).
• Red, Green, Blue: Channel values (0..255) shown/edited by the picker.
• HorizontalReverse: Invert horizontal axis direction (left <-> right).
• VerticalReverse: Invert vertical axis direction (top <-> bottom).
• HorizontalMin, HorizontalMax: Minimum and maximum values for the horizontal axis.
• VerticalMin, VerticalMax: Minimum and maximum values for the vertical axis.
• CurrentColor: Helper property to get/set the combined RGB color.
• AlphaPreview: Alpha preview opacity used in range rendering.
• RangeBackground: Appearance settings for checkerboard/transparent settings.
• Layout: Visual layout for the axis picker (OverlapThumb, InsideThumb).
• ThumbKind: Thumb kind (Circle, Cross).
• ThumbStyle: Thumb rendering style (Color, Invert, Mixed).
• ThumbSize: Thumb size or auto behavior.
• PositionLineVisible: Show a position indicator line on the 2D range.

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TTurboHslLinePicker

A linear picker for HSL components: Hue, Saturation, Lightness.

Main properties:

• Hue, Saturation, Lightness: HSL component values (0..1) edited by the control.
• Kind: Selected component (Hue, Saturation, Lightness).
• Min: Minimum value of the picker range.
• Max: Maximum value of the picker range.
• Reverse: Invert the value-to-position mapping.
• CurrentColor: Helper property to get/set the combined RGB color.
• ColorModulation: Enable color modulation in the range preview.
• AlphaPreview: Alpha preview opacity used in range rendering.
• RangeBackground: Appearance settings for checkerboard/transparent settings.
• PreviewStyle: Preview visualization style (gradient/lines) without color modulation.
• Orientation: Control orientation (Horizontal, Vertical).
• Layout: Visual arrangement of the thumb(s) and arrows (ExternalArrows, InternalArrows, CenterArrows, OverlapBox, InsideBox).
• ThumbLayout: Which thumbs are visible (First, Second, Both).
• ThumbSize: Thumb size settings (Width/Height or Auto).
• PositionLineVisible: Show a position indicator line on the range.
• ForceRepaint: Force immediate repaint when the picker or its range changes.

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TTurboHslAxisPicker

A 2D HSL axis picker for selecting two color components at once (for example: Saturation * Lightness).

Main properties:

• HorizontalKind: Which channel maps to the horizontal axis (Hue, Saturation, Lightness).
• VerticalKind: Which channel maps to the vertical axis (Hue, Saturation, Lightness).
• Hue, Saturation, Lightness: Component values (0..1) shown/edited by the picker.
• HorizontalReverse: Invert horizontal axis direction (left <-> right).
• VerticalReverse: Invert vertical axis direction (top <-> bottom).
• HorizontalMin, HorizontalMax: Minimum and maximum values for the horizontal axis.
• VerticalMin, VerticalMax: Minimum and maximum values for the vertical axis.
• CurrentColor: Helper property to get/set the combined RGB color.
• AlphaPreview: Alpha preview opacity used in range rendering.
• RangeBackground: Appearance settings for checkerboard/transparent settings.
• Layout: Visual layout for the axis picker (OverlapThumb, InsideThumb).
• ThumbKind: Thumb kind (Circle, Cross).
• ThumbStyle: Thumb rendering style (Color, Invert, Mixed).
• ThumbSize: Thumb size or auto behavior.
• PositionLineVisible: Show a position indicator line on the 2D range.

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TTurboHsvLinePicker

A linear picker for HSV components: Hue, Saturation, Value.

Main properties:

• Hue, Saturation, Value: HSV component values (0..1) edited by the control.
• Kind: Selected component (Hue, Saturation, Value).
• Min: Minimum value of the picker range.
• Max: Maximum value of the picker range.
• Reverse: Invert the value-to-position mapping.
• CurrentColor: Helper property to get/set the combined RGB color.
• ColorModulation: Enable color