Internals: Cleanup FindBestPopupWindowPos() to be more digestible, since we are bounds to rework the logic there. No functional changes intended

7 years ago · 8959c64b33
parent abe5ad3c7a
commit 8959c64b33
2 changed files with 27 additions and 15 deletions
--- a/imgui.cpp
+++ b/imgui.cpp
@ -656,7 +656,7 @@ static ImRect           GetVisibleRect();
 static void             CloseInactivePopups(ImGuiWindow* ref_window);
 static void             ClosePopupToLevel(int remaining);
 static ImGuiWindow*     GetFrontMostModalRootWindow();
-static ImVec2           FindBestPopupWindowPos(const ImVec2& base_pos, const ImVec2& size, int* last_dir, const ImRect& rect_to_avoid);
+static ImVec2           FindBestPopupWindowPos(const ImVec2& base_pos, const ImVec2& size, ImGuiDir* last_dir, const ImRect& rect_to_avoid);

 static bool             InputTextFilterCharacter(unsigned int* p_char, ImGuiInputTextFlags flags, ImGuiTextEditCallback callback, void* user_data);
 static int              InputTextCalcTextLenAndLineCount(const char* text_begin, const char** out_text_end);
@ -1845,7 +1845,7 @@ ImGuiWindow::ImGuiWindow(const char* name)
    AutoFitFramesX = AutoFitFramesY = -1;
    AutoFitOnlyGrows = false;
    AutoFitChildAxises = 0x00;
-    AutoPosLastDirection = -1;
+    AutoPosLastDirection = ImGuiDir_None;
    HiddenFrames = 0;
    SetWindowPosAllowFlags = SetWindowSizeAllowFlags = SetWindowCollapsedAllowFlags = ImGuiCond_Always | ImGuiCond_Once | ImGuiCond_FirstUseEver | ImGuiCond_Appearing;
    SetWindowPosVal = SetWindowPosPivot = ImVec2(FLT_MAX, FLT_MAX);
@ -4017,28 +4017,39 @@ static void CheckStacksSize(ImGuiWindow* window, bool write)
    IM_ASSERT(p_backup == window->DC.StackSizesBackup + IM_ARRAYSIZE(window->DC.StackSizesBackup));
 }

-static ImVec2 FindBestPopupWindowPos(const ImVec2& base_pos, const ImVec2& size, int* last_dir, const ImRect& r_inner)
+static ImVec2 FindBestPopupWindowPos(const ImVec2& base_pos, const ImVec2& size, ImGuiDir* last_dir, const ImRect& r_avoid)
 {
    const ImGuiStyle& style = GImGui->Style;

-    // Clamp into visible area while not overlapping the cursor. Safety padding is optional if our popup size won't fit without it.
+    // r_avoid = the rectangle to avoid (e.g. for tooltip it is a rectangle around the mouse cursor which we want to avoid. for popups it's a small point around the cursor.)
+    // r_outer = the visible area rectangle, minus safe area padding. If our popup size won't fit because of safe area padding we ignore it.
    ImVec2 safe_padding = style.DisplaySafeAreaPadding;
    ImRect r_outer(GetVisibleRect());
    r_outer.Expand(ImVec2((size.x - r_outer.GetWidth() > safe_padding.x*2) ? -safe_padding.x : 0.0f, (size.y - r_outer.GetHeight() > safe_padding.y*2) ? -safe_padding.y : 0.0f));
    ImVec2 base_pos_clamped = ImClamp(base_pos, r_outer.Min, r_outer.Max - size);
+    //GImGui->OverlayDrawList.AddRect(r_avoid.Min, r_avoid.Max, IM_COL32(255,0,0,255));
+    //GImGui->OverlayDrawList.AddRect(r_outer.Min, r_outer.Max, IM_COL32(0,255,0,255));

-    for (int n = (*last_dir != -1) ? -1 : 0; n < 4; n++)   // Last, Right, down, up, left. (Favor last used direction).
+    const ImGuiDir dir_prefered_order[ImGuiDir_Count_] = { ImGuiDir_Right, ImGuiDir_Down, ImGuiDir_Up, ImGuiDir_Left };
+    for (int n = (*last_dir != ImGuiDir_None) ? -1 : 0; n < ImGuiDir_Count_; n++)
    {
-        const int dir = (n == -1) ? *last_dir : n;
-        ImRect rect(dir == 0 ? r_inner.Max.x : r_outer.Min.x, dir == 1 ? r_inner.Max.y : r_outer.Min.y, dir == 3 ? r_inner.Min.x : r_outer.Max.x, dir == 2 ? r_inner.Min.y : r_outer.Max.y);
-        if (rect.GetWidth() < size.x || rect.GetHeight() < size.y)
+        const ImGuiDir dir = (n == -1) ? *last_dir : dir_prefered_order[n];
+        float avail_w = (dir == ImGuiDir_Left ? r_avoid.Min.x : r_outer.Max.x) - (dir == ImGuiDir_Right ? r_avoid.Max.x : r_outer.Min.x);
+        if (avail_w < size.x)
            continue;
+        float avail_h = (dir == ImGuiDir_Down ? r_avoid.Min.y : r_outer.Max.y) - (dir == ImGuiDir_Down ? r_avoid.Max.y : r_outer.Min.y);
+        if (avail_h < size.y)
+            continue;
+
+        ImVec2 pos;
+        pos.x = (dir == ImGuiDir_Left) ? r_avoid.Min.x - size.x : (dir == ImGuiDir_Right) ? r_avoid.Max.x : base_pos_clamped.x;
+        pos.y = (dir == ImGuiDir_Up)   ? r_avoid.Min.y - size.y : (dir == ImGuiDir_Down)  ? r_avoid.Max.y : base_pos_clamped.y;
        *last_dir = dir;
-        return ImVec2(dir == 0 ? r_inner.Max.x : dir == 3 ? r_inner.Min.x - size.x : base_pos_clamped.x, dir == 1 ? r_inner.Max.y : dir == 2 ? r_inner.Min.y - size.y : base_pos_clamped.y);
+        return pos;
    }

    // Fallback, try to keep within display
-    *last_dir = -1;
+    *last_dir = ImGuiDir_None;
    ImVec2 pos = base_pos;
    pos.x = ImMax(ImMin(pos.x + size.x, r_outer.Max.x) - size.x, r_outer.Min.x);
    pos.y = ImMax(ImMin(pos.y + size.y, r_outer.Max.y) - size.y, r_outer.Min.y);
@ -4382,7 +4393,7 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
        if (window_just_activated_by_user)
        {
            // Popup first latch mouse position, will position itself when it appears next frame
-            window->AutoPosLastDirection = -1;
+            window->AutoPosLastDirection = ImGuiDir_None;
            if ((flags & ImGuiWindowFlags_Popup) != 0 && !window_pos_set_by_api)
                window->PosFloat = g.IO.MousePos;
        }
@ -4523,9 +4534,9 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
        if ((flags & ImGuiWindowFlags_Tooltip) != 0 && !window_pos_set_by_api)
        {
            ImVec2 ref_pos = g.IO.MousePos;
-            ImRect rect_to_avoid(ref_pos.x - 16, ref_pos.y - 8, ref_pos.x + 24, ref_pos.y + 24); // FIXME: Completely hard-coded. Perhaps center on cursor hit-point instead?
+            ImRect rect_to_avoid(ref_pos.x - 16, ref_pos.y - 8, ref_pos.x + 24, ref_pos.y + 24); // FIXME: Completely hard-coded. Store boxes in mouse cursor data? Scale? Center on cursor hit-point?
            window->PosFloat = FindBestPopupWindowPos(ref_pos, window->Size, &window->AutoPosLastDirection, rect_to_avoid);
-            if (window->AutoPosLastDirection == -1)
+            if (window->AutoPosLastDirection == ImGuiDir_None)
                window->PosFloat = ref_pos + ImVec2(2,2); // If there's not enough room, for tooltip we prefer avoiding the cursor at all cost even if it means that part of the tooltip won't be visible.
        }

--- a/imgui_internal.h
+++ b/imgui_internal.h
@ -248,7 +248,8 @@ enum ImGuiDir
    ImGuiDir_Left    = 0,
    ImGuiDir_Right   = 1,
    ImGuiDir_Up      = 2,
-    ImGuiDir_Down    = 3
+    ImGuiDir_Down    = 3,
+    ImGuiDir_Count_
 };

 // 2D axis aligned bounding-box
@ -726,7 +727,7 @@ struct IMGUI_API ImGuiWindow
    int                     AutoFitFramesX, AutoFitFramesY;
    bool                    AutoFitOnlyGrows;
    int                     AutoFitChildAxises;
-    int                     AutoPosLastDirection;
+    ImGuiDir                AutoPosLastDirection;
    int                     HiddenFrames;
    ImGuiCond               SetWindowPosAllowFlags;             // store condition flags for next SetWindowPos() call.
    ImGuiCond               SetWindowSizeAllowFlags;            // store condition flags for next SetWindowSize() call.