Updated ImGui.

3rdparty/dear-imgui/imgui.cpp

@@ -11335,23 +11335,51 @@ void ImGui::EndCombo()
     EndPopup();
 }
 
+// Getter for the old Combo() API: const char*[]
+static bool Items_ArrayGetter(void* data, int idx, const char** out_text)
+{
+    const char* const* items = (const char* const*)data;
+    if (out_text)
+        *out_text = items[idx];
+    return true;
+}
+
+// Getter for the old Combo() API: "item1\0item2\0item3\0"
+static bool Items_SingleStringGetter(void* data, int idx, const char** out_text)
+{
+    // FIXME-OPT: we could pre-compute the indices to fasten this. But only 1 active combo means the waste is limited.
+    const char* items_separated_by_zeros = (const char*)data;
+    int items_count = 0;
+    const char* p = items_separated_by_zeros;
+    while (*p)
+    {
+        if (idx == items_count)
+            break;
+        p += strlen(p) + 1;
+        items_count++;
+    }
+    if (!*p)
+        return false;
+    if (out_text)
+        *out_text = p;
+    return true;
+}
+
 // Old API, prefer using BeginCombo() nowadays if you can.
 bool ImGui::Combo(const char* label, int* current_item, bool (*items_getter)(void*, int, const char**), void* data, int items_count, int popup_max_height_in_items)
 {
     ImGuiContext& g = *GImGui;
 
-    const char* preview_text = NULL;
+    // Call the getter to obtain the preview string which is a parameter to BeginCombo()
+    const char* preview_value = NULL;
     if (*current_item >= 0 && *current_item < items_count)
-        items_getter(data, *current_item, &preview_text);
+        items_getter(data, *current_item, &preview_value);
 
-    // The old Combo() API exposed "popup_max_height_in_items". The new more general BeginCombo() API doesn't, so we emulate it here.
+    // The old Combo() API exposed "popup_max_height_in_items". The new more general BeginCombo() API doesn't have/need it, but we emulate it here.
     if (popup_max_height_in_items != -1 && !g.NextWindowData.SizeConstraintCond)
-    {
-        float popup_max_height = CalcMaxPopupHeightFromItemCount(popup_max_height_in_items);
-        SetNextWindowSizeConstraints(ImVec2(0,0), ImVec2(FLT_MAX, popup_max_height));
-    }
+        SetNextWindowSizeConstraints(ImVec2(0,0), ImVec2(FLT_MAX, CalcMaxPopupHeightFromItemCount(popup_max_height_in_items)));
 
-    if (!BeginCombo(label, preview_text, 0))
+    if (!BeginCombo(label, preview_value, ImGuiComboFlags_None))
         return false;
 
     // Display items
@@ -11378,34 +11406,6 @@ bool ImGui::Combo(const char* label, int* current_item, bool (*items_getter)(voi
     return value_changed;
 }
 
-static bool Items_ArrayGetter(void* data, int idx, const char** out_text)
-{
-    const char* const* items = (const char* const*)data;
-    if (out_text)
-        *out_text = items[idx];
-    return true;
-}
-
-static bool Items_SingleStringGetter(void* data, int idx, const char** out_text)
-{
-    // FIXME-OPT: we could pre-compute the indices to fasten this. But only 1 active combo means the waste is limited.
-    const char* items_separated_by_zeros = (const char*)data;
-    int items_count = 0;
-    const char* p = items_separated_by_zeros;
-    while (*p)
-    {
-        if (idx == items_count)
-            break;
-        p += strlen(p) + 1;
-        items_count++;
-    }
-    if (!*p)
-        return false;
-    if (out_text)
-        *out_text = p;
-    return true;
-}
-
 // Combo box helper allowing to pass an array of strings.
 bool ImGui::Combo(const char* label, int* current_item, const char* const items[], int items_count, int height_in_items)
 {
@@ -11413,7 +11413,7 @@ bool ImGui::Combo(const char* label, int* current_item, const char* const items[
     return value_changed;
 }
 
-// Combo box helper allowing to pass all items in a single string.
+// Combo box helper allowing to pass all items in a single string literal holding multiple zero-terminated items "item1\0item2\0" 
 bool ImGui::Combo(const char* label, int* current_item, const char* items_separated_by_zeros, int height_in_items)
 {
     int items_count = 0;
@@ -11428,7 +11428,7 @@ bool ImGui::Combo(const char* label, int* current_item, const char* items_separa
 }
 
 // Tip: pass an empty label (e.g. "##dummy") then you can use the space to draw other text or image.
-// But you need to make sure the ID is unique, e.g. enclose calls in PushID/PopID.
+// But you need to make sure the ID is unique, e.g. enclose calls in PushID/PopID or use ##unique_id.
 bool ImGui::Selectable(const char* label, bool selected, ImGuiSelectableFlags flags, const ImVec2& size_arg)
 {
     ImGuiWindow* window = GetCurrentWindow();

3rdparty/dear-imgui/imgui.h

@@ -339,7 +339,7 @@ namespace ImGui
     IMGUI_API void          Bullet();                                                       // draw a small circle and keep the cursor on the same line. advance cursor x position by GetTreeNodeToLabelSpacing(), same distance that TreeNode() uses
 
     // Widgets: Combo Box
-    // The new BeginCombo()/EndCombo() api allows you to manage your contents and selection state however you want it.
+    // The new BeginCombo()/EndCombo() api allows you to manage your contents and selection state however you want it, by creating e.g. Selectable() items.
     // The old Combo() api are helpers over BeginCombo()/EndCombo() which are kept available for convenience purpose.
     IMGUI_API bool          BeginCombo(const char* label, const char* preview_value, ImGuiComboFlags flags = 0);
     IMGUI_API void          EndCombo(); // only call EndCombo() if BeginCombo() returns true!

3rdparty/dear-imgui/imgui_draw.cpp

@@ -19,13 +19,13 @@
 
 #include <stdio.h>      // vsnprintf, sscanf, printf
 #if !defined(alloca)
-#ifdef _WIN32
+#if defined(__GLIBC__) || defined(__sun) || defined(__CYGWIN__)
+#include <alloca.h>     // alloca (glibc uses <alloca.h>. Note that Cygwin may have _WIN32 defined, so the order matters here)
+#elif defined(_WIN32)
 #include <malloc.h>     // alloca
 #if !defined(alloca)
 #define alloca _alloca  // for clang with MS Codegen
 #endif
-#elif defined(__GLIBC__) || defined(__sun)
-#include <alloca.h>     // alloca
 #else
 #include <stdlib.h>     // alloca
 #endif