;;<br>Parameters<br>hdev <br>Handle to the device. This parameter is the GDI handle received by the driver's DrvCompletePDEV function. <br>devAttr <br>Specifies the attribute for which GDI should return information. This parameter must be QDA_ACCELERATION_LEVEL, which queries the driver accelerations that GDI currently allows. <br>pvIn <br>Reserved for system use. This parameter is currently ignored by GDI. <br>ulInSize <br>Reserved for system use. This parameter is currently ignored by GDI. <br>pvOut <br>Pointer to a buffer of ulOutSize bytes in which GDI writes information about the attribute being queried. When devAttr is QDA_ACCELERATION_LEVEL, GDI writes in the buffer a DWORD value from 0 through 5 that indicates the current acceleration level. See Display Driver Testing Tools for a description of the acceleration levels. <br>ulOutSize <br>Specifies the size, in bytes, of the buffer to which pvOut points. <br>Return Value<br>EngQueryDeviceAttribute returns TRUE upon success; otherwise, it returns FALSE.<br><br>Headers<br>Declared in winddi.h. Include winddi.h.<br><br>Comments<br>The video card's acceleration level can be dynamically set through the Display program in Control Panel. EngQueryDeviceAttribute allows the driver to determine the acceleration level currently set.<br><br><br><br>When devAttr is QDA_ACCELERATION_LEVEL, GDI writes in the buffer a DWORD value from 0 through 5 that indicates the current acceleration level.<br>当devAttr 是QDA_ACCELERATION_LEVEL,GDI一个0到5的DWORD到这个BUFFER中,这个值标明当前的加速级别.