![]() Applications that wish to respond to fifth actions must retrieve information specific to the pointer type to determine if the second extended mouse (XButton2) button is pressed.īecause the pointer may make contact with the device over a non-trivial area, this point location may be a simplification of a more complex pointer area. IS_POINTER_FIFTHBUTTON_WPARAM(wParam): a flag that indicates whether the specified pointer took fifth action. Applications that wish to respond to fourth actions must retrieve information specific to the pointer type to determine if the first extended mouse (XButton1) button is pressed. IS_POINTER_FOURTHBUTTON_WPARAM(wParam): a flag that indicates whether the specified pointer took fourth action. For example, an application can determine the buttons states of a pen by calling GetPointerPenInfo and examining the flags that specify button states. IS_POINTER_THIRDBUTTON_WPARAM(wParam): a flag that indicates whether there are one or more tertiary actions based on the pointer type applications that wish to respond to tertiary actions must retrieve information specific to the pointer type to determine which tertiary buttons are pressed. A pen pointer will have this set when it is in contact with the digitizer surface with the pen barrel button pressed. ![]() ![]() This is analogous to a mouse right button down.IS_POINTER_SECONDBUTTON_WPARAM(wParam): a flag that indicates whether there is a secondary action. A pen pointer will have this set when it is in contact with the digitizer surface with no buttons pressed.A touch pointer will have this set when it is in contact with the digitizer surface.This is analogous to a mouse left button down.IS_POINTER_FIRSTBUTTON_WPARAM(wParam): a flag that indicates whether there is a primary action. IS_POINTER_PRIMARY_WPARAM(wParam): indicates that this pointer has been designated as primary. This flag is not set on messages that indicate a hovering pointer. IS_POINTER_INCONTACT_WPARAM(wParam): a flag that indicates whether this message was generated by a pointer that is in contact with the window surface. This flag is not set on messages that indicate that the pointer has left detection range IS_POINTER_INRANGE_WPARAM(wParam): a flag that indicates whether this message was generated by a pointer during its lifetime. IS_POINTER_NEW_WPARAM(wParam): a flag that indicates whether this message represents the first input generated by a new pointer. GET_POINTERID_WPARAM(wParam): the pointer identifier. Use the following macros to retrieve information from the wParam parameter. #define WM_POINTERDOWN 0x0246Ĭontains information about the pointer. For more information, see Writing High-DPI Win32 Applications. DPI virtualization provides automatic scaling support to applications that are not DPI aware and is active by default (users can turn it off). If your app is not DPI aware, screen coordinates contained in pointer messages and related structures might appear inaccurate due to DPI virtualization. This input message targets the window over which the pointer makes contact, and the pointer is implicitly captured to the window so that the window continues to receive input for the pointer until it breaks contact.Ī window receives this message through its WindowProc function.ĭesktop apps should be DPI aware. ![]() In my experience, though, as long as you're using this hook on smaller components that don't have a big DOM impact, you should be just fine.Posted when a pointer makes contact over the client area of a window. Use this hook in the small “leaf node” components near the bottom of the tree.įor maximum performance, you can use a library like React Spring or Framer Motion, which will allow you to update values without triggering React renders. It shouldn't be used in a top-level component like App or Homepage, since that will cause a huge chunk of your React tree to re-render very often. That said, you do still need to be a bit careful where you use this hook. No matter how hard I tried, I couldn't come up with a contrived scenario where the throttle actually improved performance (while still updating often enough for smooth animations). In testing, though, it seemed to make performance worse. Originally, this hook included “throttle” functionality, which would limit the updates to a user-specified interval. This can be dozens and dozens of times a second. This component will re-render whenever the user moves the mouse.
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