Inputs: Add optional support for untranslated key codes for backends

ocornut · Dec 13, 2021 · e6d69b6 · e6d69b6
1 parent c7ba4d6
commit e6d69b6
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Showing 3 changed files with 23 additions and 2 deletions.
diff --git a/imgui.cpp b/imgui.cpp
@@ -1095,6 +1095,8 @@ ImGuiIO::ImGuiIO()
     MouseDoubleClickMaxDist = 6.0f;
     for (int i = 0; i < ImGuiKey_COUNT; i++)
         KeyMap[i] = -1;
+    for (int i = 0; i < ImGuiKey_COUNT; i++)
+        ScancodeMap[i] = -1;
     KeyRepeatDelay = 0.275f;
     KeyRepeatRate = 0.050f;
     UserData = NULL;
@@ -4786,6 +4788,21 @@ int ImGui::GetKeyIndex(ImGuiKey imgui_key)
     return g.IO.KeyMap[imgui_key];
 }
 
+int ImGui::GetUntranslatedKeyIndex(ImGuiKey imgui_key)
+{
+    IM_ASSERT(imgui_key >= 0 && imgui_key < ImGuiKey_COUNT);
+    ImGuiContext& g = *GImGui;
+
+    if (g.IO.BackendFlags & ImGuiBackednFlags_HasUntranslatedKeys)
+    {
+        int key_index = g.IO.ScancodeMap[imgui_key];
+        if (key_index >= 0)
+            return key_index;
+    }
+
+    return g.IO.KeyMap[imgui_key];
+}
+
 const char* ImGui::GetKeyName(ImGuiKey imgui_key)
 {
     static const char* const key_names[] =

diff --git a/imgui.h b/imgui.h
@@ -886,6 +886,7 @@ namespace ImGui
     // - For 'int user_key_index' you can use your own indices/enums according to how your backend/engine stored them in io.KeysDown[].
     // - We don't know the meaning of those value. You can use GetKeyIndex() to map a ImGuiKey_ value into the user index.
     IMGUI_API int           GetKeyIndex(ImGuiKey imgui_key);                                    // map ImGuiKey_* values into user's key index. == io.KeyMap[key]
+    IMGUI_API int           GetUntranslatedKeyIndex(ImGuiKey imgui_key);                        // map ImGuiKey_* values into user's key index == io.ScancodeMap[key] if supported, otherwise act like GetKeyIndex
     IMGUI_API const char*   GetKeyName(ImGuiKey imgui_key);                                     // returns English name of the key
     IMGUI_API int           FindImGuiKey(int user_key_index);                                   // finds ImGuiKey_* associated to specified user_key_index. Returns ImGuiKey_None if not found.
     IMGUI_API bool          IsKeyDown(int user_key_index);                                      // is key being held. == io.KeysDown[user_key_index].
@@ -1544,7 +1545,8 @@ enum ImGuiBackendFlags_
     ImGuiBackendFlags_HasGamepad            = 1 << 0,   // Backend Platform supports gamepad and currently has one connected.
     ImGuiBackendFlags_HasMouseCursors       = 1 << 1,   // Backend Platform supports honoring GetMouseCursor() value to change the OS cursor shape.
     ImGuiBackendFlags_HasSetMousePos        = 1 << 2,   // Backend Platform supports io.WantSetMousePos requests to reposition the OS mouse position (only used if ImGuiConfigFlags_NavEnableSetMousePos is set).
-    ImGuiBackendFlags_RendererHasVtxOffset  = 1 << 3    // Backend Renderer supports ImDrawCmd::VtxOffset. This enables output of large meshes (64K+ vertices) while still using 16-bit indices.
+    ImGuiBackendFlags_RendererHasVtxOffset  = 1 << 3,   // Backend Renderer supports ImDrawCmd::VtxOffset. This enables output of large meshes (64K+ vertices) while still using 16-bit indices.
+    ImGuiBackednFlags_HasUntranslatedKeys   = 1 << 4,   // Backend Platform supports physical keyboard layout mapping to ImGuiKey_XXX.
 };
 
 // Enumeration for PushStyleColor() / PopStyleColor()
@@ -1932,7 +1934,8 @@ struct ImGuiIO
     float       MouseDoubleClickTime;           // = 0.30f          // Time for a double-click, in seconds.
     float       MouseDoubleClickMaxDist;        // = 6.0f           // Distance threshold to stay in to validate a double-click, in pixels.
     float       MouseDragThreshold;             // = 6.0f           // Distance threshold before considering we are dragging.
-    int         KeyMap[ImGuiKey_COUNT];         // <unset>          // Map of indices into the KeysDown[512] entries array which represent your "native" keyboard state.
+    int         KeyMap[ImGuiKey_COUNT];         // <unset>          // Map of logical ImGuiKey_XXX key indices into the KeysDown[512] entries array which represent your "native" keyboard state.
+    int         ScancodeMap[ImGuiKey_COUNT];    // <unset>          // Map of physical ImGuiKey_XXXX key indices into the KeysDown[512] entries array which represent your "native" keyboard state.
     float       KeyRepeatDelay;                 // = 0.250f         // When holding a key/button, time before it starts repeating, in seconds (for buttons in Repeat mode, etc.).
     float       KeyRepeatRate;                  // = 0.050f         // When holding a key/button, rate at which it repeats, in seconds.
     void*       UserData;                       // = NULL           // Store your own data for retrieval by callbacks.

diff --git a/imgui_demo.cpp b/imgui_demo.cpp
@@ -486,6 +486,7 @@ void ImGui::ShowDemoWindow(bool* p_open)
             ImGui::CheckboxFlags("io.BackendFlags: HasMouseCursors",      &backend_flags, ImGuiBackendFlags_HasMouseCursors);
             ImGui::CheckboxFlags("io.BackendFlags: HasSetMousePos",       &backend_flags, ImGuiBackendFlags_HasSetMousePos);
             ImGui::CheckboxFlags("io.BackendFlags: RendererHasVtxOffset", &backend_flags, ImGuiBackendFlags_RendererHasVtxOffset);
+            ImGui::CheckboxFlags("io.BackendFlags: HasUntranslatedKeys",  &backend_flags, ImGuiBackednFlags_HasUntranslatedKeys);
             ImGui::TreePop();
             ImGui::Separator();
         }