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Using TRasterLab

TRasterLab is a flexible component for displaying texts in form of dot-matrix displays. It has been designed to provide a flicker-free scrollable display. The utilization of TRasterLab is straightforward. Put it on the form where you want it to be and set up the properties as you need them.


The appearance of TRasterLab can be influenced by a number of properties which control the colors, the size of the dots, the font, and its dynamic behavior. The colors of the dot-matrix display are controlled by the properties ColorLabBakg, ColorDotOn, and ColorDotOff, which influence the color of the background, and the color of active and inactive dots, respectively. The size of the dots can be set by the property DotSize (in pixels), their spacing by DotSpacing. Please note that the visual appearance of the dot-matrix characters is also affected by the property CharBlockMode.

By default, TRasterLab uses an internal default font, which is not available as a standard Windows font. However, you can assign any Windows font to the dot-matrix display by using either the method CreateBitFont, or, even simpler, by setting the Font property. In addition to the style of the font, you may use either a fixed-width font or a proportional font by setting the property Proportional accordingly. If you want to have total control over the character set, you could design your own font by using the property CharMatrix.

The relative position of the text within the dot-matrix display can be controlled by the properties PosX, and PosY. If the property AutoCenter is TRUE the text on the display is centered by adjusting the property PosX accordingly.

As an alternative, you may activate automatic scrolling by setting the property ScrollMode to a value other than rdsmOff. The scroll speed can be controlled by the properties ScrollIncrement and ScrollInterval. You can force the display to scroll the text in a loop by setting the property ScrollLoop to TRUE. Scrolling triggers two events: OnScrollTimer and OnScrollLoopRestart, which give you the opportunity to influence the features of the display during scrolling (e.g. to change the color during scrolling).

Last Update: 2023-Feb-06