DemoGL::About::The startup dialog

The startup dialog.

DemoGL provides true resolution/bitdepth/screendepth/soundhardware independance for the developer. This way the developer just programs for one resolution (using floating point coordinates instead of pixel oriented int coordinates) and bitdepth (32bpp), and the end user can select the settings that fits his/her system best. DemoGL powered applications by default start with the startup dialog (a developer can provide his own startup dialog, see for more information DEMOGL_AppRun in the DemoGL Reference manual on a discussion about runtypes). The startup dialog provides the user to set all kinds of runtime settings, like windowed or full screen execution, window resolution, bitdepth for textures, bitdepth for the framebuffer, soundsystem related options like EAX/A3D support, playback quality etc. The developer can customize this default startup dialog by supplying a bitmap as resource in the application. The bitmap should have a size of 91x433 pixels (width X height). The resource should have ID symbol 140.

A typical startup dialog looks like this:

A typical startup dialog

The default settings of the different controls on the startup dialog are retrieved from the registry and if the registry doesn't contain any settings for the particular application, DemoGL fill use the supplied settings in the SStartupDat structure, passed to DEMOGL_AppRun when the application execution was started. When an application is ran for the first time on a machine, the registry will not contain any settings for the application. When the user selects the option 'Save settings in registry' on the startup dialog, DemoGL will save all control's settings to the registry key: HKCU/Software/DemoGL/Application/Application title/AppData. When the application is ran again, DemoGL will read these settings and will overrule any setting set in the SStartupDat structure passed to DEMOGL_AppRun.

A developer can block certain settings in the startup dialog. When the developer doesn't want any rescaling of texturedata, this feature can be blocked by setting the variable DGL_VF_NEVERRESCALETEXTURES using DEMOGL_SetVariable. When the application doesn't use any sound, it's recommended to block the enable sound option in the startup dialog. This can be done by setting the SStartupDat member m_bSound to false.

Screensavers
When the application is a screensaver, DemoGL will not start with the startup dialog, because a screensaver should start immediately. Instead, DemoGL will show the startup dialog when the user presses 'Settings' on the screensaver tab in 'display properties' in Windows. This is default behaviour which can be overruled by providing an own dialog for 'configurating' the screensaver properties. See DEMOGL_AppRun in the DemoGL Reference manual for details.


Last changed on 11-mar-2001

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