io.MouseDown[0]=g_MousePressed[0]||(mouse_buttons&SDL_BUTTON(SDL_BUTTON_LEFT))!=0;// If a mouse press event came, always pass it as "mouse held this frame", so we don't miss click-release events that are shorter than 1 frame.
// This code supports multiple OS Windows mapped into different ImGui viewports,
// So it is a little more complicated than your typical single-viewport binding code (which only needs to set io.MousePos from the WM_MOUSEMOVE handler)
// This is what imgui needs from the back-end to support multiple windows:
// - io.MousePos = mouse position in absolute coordinate (e.g. io.MousePos == ImVec2(0,0) when it is on the upper-left of the primary monitor)
// - io.MousePosViewport = viewport which mouse position is based from (generally the focused/active/capturing viewport)
// - io.MouseHoveredWindow = viewport which mouse is hovering, **regardless of it being the active/focused window**, **regardless of another window holding mouse captured**. [Optional]
// Because of that, it is a little more complicated than your typical single-viewport binding code.
// A) In Single-viewport mode imgui needs:
// - io.MousePos ............... mouse position, in client window coordinates (what you'd get from GetCursorPos+ScreenToClient() or from WM_MOUSEMOVE)
// io.MousePos is (0,0) when the mouse is on the upper-left corner of the application window.
// B) In Multi-viewport mode imgui needs: (when ImGuiConfigFlags_ViewportsEnable is set)
// - io.MousePos ............... mouse position, in OS absolute coordinates (what you'd get from GetCursorPos(), or from WM_MOUSEMOVE+viewport->Pos).
// io.MousePos is (0,0) when the mouse is on the upper-left of the primary monitor.
// - io.MousePosViewport ....... viewport which mouse position is based from (generally the focused/active/capturing viewport)
// - io.MouseHoveredViewport ... [optional] viewport which mouse is hovering, with _very_ specific/strict conditions (Read comments next to io.MouseHoveredViewport. This is _NOT_ easy to provide in many high-level engine because of how we handle the ImGuiViewportFlags_NoInputs flag)
// This function overwrite the value of io.MousePos normally updated by the WM_MOUSEMOVE handler.
// We keep the WM_MOUSEMOVE handling code so that WndProc function can be copied as-in in applications which do not need multiple OS windows support.
// We keep the WM_MOUSEMOVE handling code so that WndProc function can be copied as-in in applications which do not need multi-viewport support.
staticvoidImGui_ImplWin32_UpdateMousePos()
{
ImGuiIO&io=ImGui::GetIO();
// Set OS mouse position if requested (rarely used, only when ImGuiConfigFlags_NavEnableSetMousePos is enabled by user)
// (When multi-viewports are enabled, all imgui positions are same as OS positions.)
// (Note that ScreenToClient() and adding +viewport->Pos are mutually cancelling each others when we have multi-viewport enabled. In single-viewport mode, viewport->Pos will be zero)
POINTpos;
if(!::GetCursorPos(&pos))
return;
// Our back-end can tell which window is under the mouse cursor (not every back-end can), so pass that info to imgui
// Start the frame. This call will update the io.WantCaptureMouse, io.WantCaptureKeyboard flag that you can use to dispatch inputs (or not) to your application.
omar
7 years ago