From 77fad80e9f367c37cf308cf3d12aaeb7ac91eb4b Mon Sep 17 00:00:00 2001
From: ocornut <omarcornut@gmail.com>
Date: Thu, 2 Jul 2015 09:10:31 -0600
Subject: [PATCH] Added CaptureInputsFromApp() to manually enforce e.g.
 keyboard capturing

---
 imgui.cpp | 18 ++++++++++++++++--
 imgui.h   |  3 ++-
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/imgui.cpp b/imgui.cpp
index ce7add0d..59992268 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -1333,6 +1333,8 @@ struct ImGuiState
     float                   FramerateSecPerFrame[120];          // calculate estimate of framerate for user
     int                     FramerateSecPerFrameIdx;
     float                   FramerateSecPerFrameAccum;
+    bool                    CaptureMouseNextFrame;              // explicit capture via CaptureInputs() sets those flags
+    bool                    CaptureKeyboardNextFrame;
     char                    TempBuffer[1024*3+1];               // temporary text buffer
 
     ImGuiState()
@@ -1394,6 +1396,7 @@ struct ImGuiState
         memset(FramerateSecPerFrame, 0, sizeof(FramerateSecPerFrame));
         FramerateSecPerFrameIdx = 0;
         FramerateSecPerFrameAccum = 0.0f;
+        CaptureMouseNextFrame = CaptureKeyboardNextFrame = false;
     }
 };
 
@@ -2189,9 +2192,10 @@ void ImGui::NewFrame()
                 mouse_earliest_button_down = i;
     }
     bool mouse_owned_by_application = mouse_earliest_button_down != -1 && !g.IO.MouseDownOwned[mouse_earliest_button_down];
-    g.IO.WantCaptureMouse = (!mouse_owned_by_application && g.HoveredWindow != NULL) || (!mouse_owned_by_application && mouse_any_down) || (g.ActiveId != 0) || (!g.OpenedPopupStack.empty());
-    g.IO.WantCaptureKeyboard = (g.ActiveId != 0);
+    g.IO.WantCaptureMouse = (!mouse_owned_by_application && g.HoveredWindow != NULL) || (!mouse_owned_by_application && mouse_any_down) || (g.ActiveId != 0) || (!g.OpenedPopupStack.empty()) || (g.CaptureMouseNextFrame);
+    g.IO.WantCaptureKeyboard = (g.ActiveId != 0) || (g.CaptureKeyboardNextFrame);
     g.MouseCursor = ImGuiMouseCursor_Arrow;
+    g.CaptureMouseNextFrame = g.CaptureKeyboardNextFrame = false;
 
     // If mouse was first clicked outside of ImGui bounds we also cancel out hovering.
     if (mouse_owned_by_application)
@@ -3003,6 +3007,12 @@ void ImGui::SetMouseCursor(ImGuiMouseCursor cursor_type)
     GImGui->MouseCursor = cursor_type;
 }
 
+void ImGui::CaptureInputsFromApp(bool capture_mouse, bool capture_keyboard)
+{
+    GImGui->CaptureMouseNextFrame |= capture_mouse;
+    GImGui->CaptureKeyboardNextFrame |= capture_keyboard;
+}
+
 bool ImGui::IsItemHovered()
 {
     ImGuiWindow* window = GetCurrentWindow();
@@ -11857,6 +11867,10 @@ void ImGui::ShowTestWindow(bool* opened)
             ImGui::Text("WantCaptureMouse: %s", io.WantCaptureMouse ? "true" : "false");
             ImGui::Text("WantCaptureKeyboard: %s", io.WantCaptureKeyboard ? "true" : "false");
 
+            ImGui::Button("Hover me\nto enforce\ninputs capture");
+            if (ImGui::IsItemHovered())
+                ImGui::CaptureInputsFromApp();
+
             ImGui::TreePop();
         }
 
diff --git a/imgui.h b/imgui.h
index 9c27dd6e..52255db0 100644
--- a/imgui.h
+++ b/imgui.h
@@ -382,9 +382,10 @@ namespace ImGui
     IMGUI_API bool          IsMouseDragging(int button = 0, float lock_threshold = -1.0f);      // is mouse dragging. if lock_threshold < -1.0f uses io.MouseDraggingThreshold
     IMGUI_API ImVec2        GetMousePos();                                                      // shortcut to ImGui::GetIO().MousePos provided by user, to be consistent with other calls
     IMGUI_API ImVec2        GetMouseDragDelta(int button = 0, float lock_threshold = -1.0f);    // dragging amount since clicking, also see: GetItemActiveDragDelta(). if lock_threshold < -1.0f uses io.MouseDraggingThreshold
-    IMGUI_API void          ResetMouseDragDelta(int button = 0);
+    IMGUI_API void          ResetMouseDragDelta(int button = 0);                                // 
     IMGUI_API ImGuiMouseCursor GetMouseCursor();                                                // get desired cursor type, reset in ImGui::NewFrame(), this updated during the frame. valid before Render(). If you use software rendering by setting io.MouseDrawCursor ImGui will render those for you
     IMGUI_API void          SetMouseCursor(ImGuiMouseCursor type);                              // set desired cursor type
+    IMGUI_API void          CaptureInputsFromApp(bool mouse = true, bool keyboard = true);      // manually enforce imgui setting the io.WantCaptureMouse / io.WantCaptureKeyboard flags next frame (your application needs to handle them). e.g. capture keyboard when your widget is being hovered.
 
     // Helpers functions to access the MemAllocFn/MemFreeFn pointers in ImGui::GetIO()
     IMGUI_API void*         MemAlloc(size_t sz);