GFA-BASIC 16 (for Windows 3.1) offered the command Dlg 3D On. to get more appealing 3D effects for dialog boxes and controls. This command was invoked before a dialog box was defined and/or created, which was the same thing in GB16. Usually the command Dlg 3D On was placed at the start of the program so that all dialogs would benefit from the 3D effect. In the background the 16-bit system CTL3D.DLL was loaded, was responsible for the painting.
What is CTL3D?
The 16-bit CTL3D.DLL hooks into dialog creation and control creation and "subclasses" the standard windows controls to give them a more appealing 3D effect. To draw 3D effects the background of the dialog boxes was painted gray, or more precisely, painted using the COLOR_BTNFACE color. That made the 3D effects possible in the first place.
This technique was first used by Microsoft Excel version 4.0. The Excel team shared the technology with the rest of the industry. Since then, the use of CTL3D has become a de facto standard and is commonly used by professional Windows applications. GFA-BASIC 16 supported the use of this DLL directly using Dlg 3D On/Off.
Still present in GB32
Starting with Windows 95 a much more pleasing 3D look is provided by default. This made CTL3D unnecessary. Despite its absence in Windows 32-bits GFA-BASIC 32 still supports the the Dlg 3D command, for backwards compatibility. However, its implementation is quite different now. The 3D effect is not accomplished through a system DLL, but by setting the default background color of the dialog box to COLOR_BTNFACE.
Dlg 3D On only works for Dlg form Ocx objects, these are the forms created using the Dialog # / End Dialog commands and accessed with the object variable name Dlg_n, where n is an ordinal value between 0 and 31.
Starting with GB32 most attributes of windows and controls are managed through OCX properties and methods. Internally, all window management is routed through the COM wrappers of the system OCX controls. This is also true for the creation of Dialog # forms. The runtime runs exactly the same code as when you create an Ocx Form. Other (16-bits compatible) window commands like OpenW, ChildW, and ParentW are created by this code as well. However when a Form is created using the Dialog command, the runtime code converts the Dlg 3D and DlgBase Xxx commands to the appropriate Form-Properties.
Dialog # id, x, y, w, h, tit$ [,flag [,height,font$] ]
The attributes of a dialog form may be set beforehand using the following commands:
|Dlg 3D On||Fills and sets background with COLOR_BTNFACE|
|Dlg 3D Off||Use default Form background-color (default)|
|DlgBase Pixel||Use x, y, w, h as pixels (default)|
|DlgBase Unit||Use x, y, w, h as dialog base units|
|DlgBase InSide||Use x, y, w, h as client size|
|DlgBase OutSide||Use x, y, w, h as window outside (default)|
|DlgBase Font font$||Use font$ for all controls|
|DlgBase Bold||Use a Bold version of font$|
|DlgBase Bold Off||Use a Normal version of font$|
|Dlg Fill||Fills and sets new background color|
The font$ parameter overrules the DlgBase Font setting.
Afterwards the background color can be changed by using properties or by using the Dlg Fill command.
These Dlg commands are used in conjunction with Dialogs only.