Internals: RenderCollapseTriangle() -> RenderTriangle(), takes a ImGuiDir

imgui.cpp

@@ -3058,31 +3058,39 @@ void ImGui::RenderFrameBorder(ImVec2 p_min, ImVec2 p_max, float rounding)
 }
 
 // Render a triangle to denote expanded/collapsed state
-void ImGui::RenderCollapseTriangle(ImVec2 p_min, bool is_open, float scale)
+void ImGui::RenderTriangle(ImVec2 p_min, ImGuiDir dir, float scale)
 {
     ImGuiContext& g = *GImGui;
     ImGuiWindow* window = g.CurrentWindow;
 
     const float h = g.FontSize * 1.00f;
-    const float r = h * 0.40f * scale;
-    ImVec2 center = p_min + ImVec2(h*0.50f, h*0.50f*scale);
+    float r = h * 0.40f * scale;
+    ImVec2 center = p_min + ImVec2(h * 0.50f, h * 0.50f * scale);
 
     ImVec2 a, b, c;
-    if (is_open)
-    {
-        center.y -= r*0.25f;
-        a = center + ImVec2(0,1)*r;
-        b = center + ImVec2(-0.866f,-0.5f)*r;
-        c = center + ImVec2(0.866f,-0.5f)*r;
-    }
-    else
-    {
-        a = center + ImVec2(1,0)*r;
-        b = center + ImVec2(-0.500f,0.866f)*r;
-        c = center + ImVec2(-0.500f,-0.866f)*r;
+    switch (dir)
+    {
+    case ImGuiDir_Up:
+        r = -r; // ...fall through, no break!
+    case ImGuiDir_Down:
+        center.y -= r * 0.25f;
+        a = ImVec2(0,1) * r;
+        b = ImVec2(-0.866f,-0.5f) * r;
+        c = ImVec2(+0.866f,-0.5f) * r;
+        break;
+    case ImGuiDir_Left:
+        r = -r; // ...fall through, no break!
+    case ImGuiDir_Right:
+        a = ImVec2(1,0) * r;
+        b = ImVec2(-0.500f,+0.866f) * r;
+        c = ImVec2(-0.500f,-0.866f) * r;
+        break;
+    default:
+        IM_ASSERT(0);
+        break;
     }
 
-    window->DrawList->AddTriangleFilled(a, b, c, GetColorU32(ImGuiCol_Text));
+    window->DrawList->AddTriangleFilled(center + a, center + b, center + c, GetColorU32(ImGuiCol_Text));
 }
 
 void ImGui::RenderBullet(ImVec2 pos)
@@ -4486,7 +4494,7 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
             // Collapse button
             if (!(flags & ImGuiWindowFlags_NoCollapse))
             {
-                RenderCollapseTriangle(window->Pos + style.FramePadding, !window->Collapsed, 1.0f);
+                RenderTriangle(window->Pos + style.FramePadding, window->Collapsed ? ImGuiDir_Right : ImGuiDir_Down, 1.0f);
             }
 
             // Close button
@@ -6211,7 +6219,7 @@ bool ImGui::TreeNodeBehavior(ImGuiID id, ImGuiTreeNodeFlags flags, const char* l
     {
         // Framed type
         RenderFrame(bb.Min, bb.Max, col, true, style.FrameRounding);
-        RenderCollapseTriangle(bb.Min + ImVec2(padding.x, text_base_offset_y), is_open, 1.0f);
+        RenderTriangle(bb.Min + ImVec2(padding.x, text_base_offset_y), is_open ? ImGuiDir_Down : ImGuiDir_Right, 1.0f);
         if (g.LogEnabled)
         {
             // NB: '##' is normally used to hide text (as a library-wide feature), so we need to specify the text range to make sure the ## aren't stripped out here.
@@ -6235,7 +6243,7 @@ bool ImGui::TreeNodeBehavior(ImGuiID id, ImGuiTreeNodeFlags flags, const char* l
         if (flags & ImGuiTreeNodeFlags_Bullet)
             RenderBullet(bb.Min + ImVec2(text_offset_x * 0.5f, g.FontSize*0.50f + text_base_offset_y));
         else if (!(flags & ImGuiTreeNodeFlags_Leaf))
-            RenderCollapseTriangle(bb.Min + ImVec2(padding.x, g.FontSize*0.15f + text_base_offset_y), is_open, 0.70f);
+            RenderTriangle(bb.Min + ImVec2(padding.x, g.FontSize*0.15f + text_base_offset_y), is_open ? ImGuiDir_Down : ImGuiDir_Right, 0.70f);
         if (g.LogEnabled)
             LogRenderedText(&text_pos, ">");
         RenderText(text_pos, label, label_end, false);
@@ -8714,7 +8722,7 @@ bool ImGui::BeginCombo(const char* label, const char* preview_value, ImVec2 popu
     const ImRect value_bb(frame_bb.Min, frame_bb.Max - ImVec2(arrow_size, 0.0f));
     RenderFrame(frame_bb.Min, frame_bb.Max, GetColorU32(ImGuiCol_FrameBg), true, style.FrameRounding);
     RenderFrame(ImVec2(frame_bb.Max.x-arrow_size, frame_bb.Min.y), frame_bb.Max, GetColorU32(popup_open || hovered ? ImGuiCol_ButtonHovered : ImGuiCol_Button), true, style.FrameRounding); // FIXME-ROUNDING
-    RenderCollapseTriangle(ImVec2(frame_bb.Max.x - arrow_size + style.FramePadding.y, frame_bb.Min.y + style.FramePadding.y), true);
+    RenderTriangle(ImVec2(frame_bb.Max.x - arrow_size + style.FramePadding.y, frame_bb.Min.y + style.FramePadding.y), ImGuiDir_Down);
 
     if (preview_value != NULL)
         RenderTextClipped(frame_bb.Min + style.FramePadding, value_bb.Max, preview_value, NULL, NULL, ImVec2(0.0f,0.0f));
@@ -9134,7 +9142,7 @@ bool ImGui::BeginMenu(const char* label, bool enabled)
         float extra_w = ImMax(0.0f, GetContentRegionAvail().x - w);
         pressed = Selectable(label, menu_is_open, ImGuiSelectableFlags_Menu | ImGuiSelectableFlags_DontClosePopups | ImGuiSelectableFlags_DrawFillAvailWidth | (!enabled ? ImGuiSelectableFlags_Disabled : 0), ImVec2(w, 0.0f));
         if (!enabled) PushStyleColor(ImGuiCol_Text, g.Style.Colors[ImGuiCol_TextDisabled]);
-        RenderCollapseTriangle(pos + ImVec2(window->MenuColumns.Pos[2] + extra_w + g.FontSize * 0.20f, 0.0f), false);
+        RenderTriangle(pos + ImVec2(window->MenuColumns.Pos[2] + extra_w + g.FontSize * 0.20f, 0.0f), ImGuiDir_Right);
         if (!enabled) PopStyleColor();
     }
 

imgui_internal.h

@@ -823,7 +823,7 @@ namespace ImGui
     IMGUI_API void          RenderFrame(ImVec2 p_min, ImVec2 p_max, ImU32 fill_col, bool border = true, float rounding = 0.0f);
     IMGUI_API void          RenderFrameBorder(ImVec2 p_min, ImVec2 p_max, float rounding = 0.0f);
     IMGUI_API void          RenderColorRectWithAlphaCheckerboard(ImVec2 p_min, ImVec2 p_max, ImU32 fill_col, float grid_step, ImVec2 grid_off, float rounding = 0.0f, int rounding_corners_flags = ~0);
-    IMGUI_API void          RenderCollapseTriangle(ImVec2 pos, bool is_open, float scale = 1.0f);
+    IMGUI_API void          RenderTriangle(ImVec2 pos, ImGuiDir dir, float scale = 1.0f);
     IMGUI_API void          RenderBullet(ImVec2 pos);
     IMGUI_API void          RenderCheckMark(ImVec2 pos, ImU32 col, float sz);
     IMGUI_API void          RenderRectFilledRangeH(ImDrawList* draw_list, const ImRect& rect, ImU32 col, float x_start_norm, float x_end_norm, float rounding);