Fix various typos. (#3161)

(found by Debian's lintian on a package that uses imgui.)
(found by codespell.)
diff --git a/imgui.cpp b/imgui.cpp
index 8e66bbe..8ce0761 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -900,7 +900,7 @@
 // Window resizing from edges (when io.ConfigWindowsResizeFromEdges = true and ImGuiBackendFlags_HasMouseCursors is set in io.BackendFlags by back-end)
 static const float WINDOWS_RESIZE_FROM_EDGES_HALF_THICKNESS = 4.0f;     // Extend outside and inside windows. Affect FindHoveredWindow().
 static const float WINDOWS_RESIZE_FROM_EDGES_FEEDBACK_TIMER = 0.04f;    // Reduce visual noise by only highlighting the border after a certain time.
-static const float WINDOWS_MOUSE_WHEEL_SCROLL_LOCK_TIMER    = 2.00f;    // Lock scrolled window (so it doesn't pick child windows that are scrolling through) for a certaint time, unless mouse moved.
+static const float WINDOWS_MOUSE_WHEEL_SCROLL_LOCK_TIMER    = 2.00f;    // Lock scrolled window (so it doesn't pick child windows that are scrolling through) for a certain time, unless mouse moved.
 
 //-------------------------------------------------------------------------
 // [SECTION] FORWARD DECLARATIONS
@@ -4231,7 +4231,7 @@
     UpdateMouseMovingWindowEndFrame();
 
     // Sort the window list so that all child windows are after their parent
-    // We cannot do that on FocusWindow() because childs may not exist yet
+    // We cannot do that on FocusWindow() because children may not exist yet
     g.WindowsTempSortBuffer.resize(0);
     g.WindowsTempSortBuffer.reserve(g.Windows.Size);
     for (int i = 0; i != g.Windows.Size; i++)
@@ -4331,7 +4331,7 @@
 }
 
 // Find window given position, search front-to-back
-// FIXME: Note that we have an inconsequential lag here: OuterRectClipped is updated in Begin(), so windows moved programatically
+// FIXME: Note that we have an inconsequential lag here: OuterRectClipped is updated in Begin(), so windows moved programmatically
 // with SetWindowPos() and not SetNextWindowPos() will have that rectangle lagging by a frame at the time FindHoveredWindow() is
 // called, aka before the next Begin(). Moving window isn't affected.
 static void FindHoveredWindow()
@@ -6360,7 +6360,7 @@
 }
 
 // Can we focus this window with CTRL+TAB (or PadMenu + PadFocusPrev/PadFocusNext)
-// Note that NoNavFocus makes the window not reachable with CTRL+TAB but it can still be focused with mouse or programmaticaly.
+// Note that NoNavFocus makes the window not reachable with CTRL+TAB but it can still be focused with mouse or programmatically.
 // If you want a window to never be focused, you may use the e.g. NoInputs flag.
 bool ImGui::IsWindowNavFocusable(ImGuiWindow* window)
 {
@@ -6814,7 +6814,7 @@
 {
     ImGuiContext& g = *GImGui;
 
-    // Verify that io.KeyXXX fields haven't been tampered with. Key mods shoudl not be modified between NewFrame() and EndFrame()
+    // Verify that io.KeyXXX fields haven't been tampered with. Key mods should not be modified between NewFrame() and EndFrame()
     const ImGuiKeyModFlags expected_key_mod_flags = GetMergedKeyModFlags();
     IM_ASSERT(g.IO.KeyMods == expected_key_mod_flags && "Mismatching io.KeyCtrl/io.KeyShift/io.KeyAlt/io.KeySuper vs io.KeyMods");
     IM_UNUSED(expected_key_mod_flags);
@@ -7811,7 +7811,7 @@
     // Make all menus and popups wrap around for now, may need to expose that policy.
     NavMoveRequestTryWrapping(window, ImGuiNavMoveFlags_LoopY);
 
-    // Child-popups don't need to be layed out
+    // Child-popups don't need to be laid out
     IM_ASSERT(g.WithinEndChild == false);
     if (window->Flags & ImGuiWindowFlags_ChildWindow)
         g.WithinEndChild = true;
diff --git a/imgui.h b/imgui.h
index 5420ac5..3dfdc39 100644
--- a/imgui.h
+++ b/imgui.h
@@ -371,7 +371,7 @@
     // Cursor / Layout
     // - By "cursor" we mean the current output position.
     // - The typical widget behavior is to output themselves at the current cursor position, then move the cursor one line down.
-    // - You can call SameLine() between widgets to undo the last carriage return and output at the right of the preceeding widget.
+    // - You can call SameLine() between widgets to undo the last carriage return and output at the right of the preceding widget.
     // - Attention! We currently have inconsistencies between window-local and absolute positions we will aim to fix with future API:
     //    Window-local coordinates:   SameLine(), GetCursorPos(), SetCursorPos(), GetCursorStartPos(), GetContentRegionMax(), GetWindowContentRegion*(), PushTextWrapPos()
     //    Absolute coordinate:        GetCursorScreenPos(), SetCursorScreenPos(), all ImDrawList:: functions.
@@ -2299,7 +2299,7 @@
     float                       Scale;              // 4     // in  // = 1.f      // Base font scale, multiplied by the per-window font scale which you can adjust with SetWindowFontScale()
     float                       Ascent, Descent;    // 4+4   // out //            // Ascent: distance from top to bottom of e.g. 'A' [0..FontSize]
     int                         MetricsTotalSurface;// 4     // out //            // Total surface in pixels to get an idea of the font rasterization/texture cost (not exact, we approximate the cost of padding between glyphs)
-    ImU8                        Used4kPagesMap[(IM_UNICODE_CODEPOINT_MAX+1)/4096/8]; // 2 bytes if ImWchar=ImWchar16, 34 bytes if ImWchar==ImWchar32. Store 1-bit for each block of 4K codepoints that has one active glyph. This is mainly used to facilitate iterations accross all used codepoints.
+    ImU8                        Used4kPagesMap[(IM_UNICODE_CODEPOINT_MAX+1)/4096/8]; // 2 bytes if ImWchar=ImWchar16, 34 bytes if ImWchar==ImWchar32. Store 1-bit for each block of 4K codepoints that has one active glyph. This is mainly used to facilitate iterations across all used codepoints.
 
     // Methods
     IMGUI_API ImFont();
diff --git a/imgui_demo.cpp b/imgui_demo.cpp
index e9652ef..a052205 100644
--- a/imgui_demo.cpp
+++ b/imgui_demo.cpp
@@ -644,7 +644,7 @@
             static bool test_drag_and_drop = false;
             ImGui::CheckboxFlags("ImGuiTreeNodeFlags_OpenOnArrow", (unsigned int*)&base_flags, ImGuiTreeNodeFlags_OpenOnArrow);
             ImGui::CheckboxFlags("ImGuiTreeNodeFlags_OpenOnDoubleClick", (unsigned int*)&base_flags, ImGuiTreeNodeFlags_OpenOnDoubleClick);
-            ImGui::CheckboxFlags("ImGuiTreeNodeFlags_SpanAvailWidth", (unsigned int*)&base_flags, ImGuiTreeNodeFlags_SpanAvailWidth); ImGui::SameLine(); HelpMarker("Extend hit area to all available width instead of allowing more items to be layed out after the node.");
+            ImGui::CheckboxFlags("ImGuiTreeNodeFlags_SpanAvailWidth", (unsigned int*)&base_flags, ImGuiTreeNodeFlags_SpanAvailWidth); ImGui::SameLine(); HelpMarker("Extend hit area to all available width instead of allowing more items to be laid out after the node.");
             ImGui::CheckboxFlags("ImGuiTreeNodeFlags_SpanFullWidth", (unsigned int*)&base_flags, ImGuiTreeNodeFlags_SpanFullWidth);
             ImGui::Checkbox("Align label with current X position", &align_label_with_current_x_position);
             ImGui::Checkbox("Test tree node as drag source", &test_drag_and_drop);
@@ -994,7 +994,7 @@
         }
         if (ImGui::TreeNode("Alignment"))
         {
-            HelpMarker("By default, Selectables uses style.SelectableTextAlign but it can be overriden on a per-item basis using PushStyleVar(). You'll probably want to always keep your default situation to left-align otherwise it becomes difficult to layout multiple items on a same line");
+            HelpMarker("By default, Selectables uses style.SelectableTextAlign but it can be overridden on a per-item basis using PushStyleVar(). You'll probably want to always keep your default situation to left-align otherwise it becomes difficult to layout multiple items on a same line");
             static bool selected[3*3] = { true, false, true, false, true, false, true, false, true };
             for (int y = 0; y < 3; y++)
             {
@@ -1065,7 +1065,7 @@
         if (ImGui::TreeNode("Resize Callback"))
         {
             // To wire InputText() with std::string or any other custom string type,
-            // you can use the ImGuiInputTextFlags_CallbackResize flag + create a custom ImGui::InputText() wrapper using your prefered type.
+            // you can use the ImGuiInputTextFlags_CallbackResize flag + create a custom ImGui::InputText() wrapper using your preferred type.
             // See misc/cpp/imgui_stdlib.h for an implementation of this using std::string.
             HelpMarker("Demonstrate using ImGuiInputTextFlags_CallbackResize to wire your resizable string type to InputText().\n\nSee misc/cpp/imgui_stdlib.h for an implementation of this for std::string.");
             struct Funcs
@@ -1082,7 +1082,7 @@
                     return 0;
                 }
 
-                // Tip: Because ImGui:: is a namespace you would typicall add your own function into the namespace in your own source files.
+                // Tip: Because ImGui:: is a namespace you would typically add your own function into the namespace in your own source files.
                 // For example, you may add a function called ImGui::InputText(const char* label, MyString* my_str).
                 static bool MyInputTextMultiline(const char* label, ImVector<char>* my_str, const ImVec2& size = ImVec2(0, 0), ImGuiInputTextFlags flags = 0)
                 {
@@ -3865,7 +3865,7 @@
             AddLog("Unknown command: '%s'\n", command_line);
         }
 
-        // On commad input, we scroll to bottom even if AutoScroll==false
+        // On command input, we scroll to bottom even if AutoScroll==false
         ScrollToBottom = true;
     }
 
diff --git a/imgui_draw.cpp b/imgui_draw.cpp
index 909949d..954c553 100644
--- a/imgui_draw.cpp
+++ b/imgui_draw.cpp
@@ -615,7 +615,7 @@
     _IdxWritePtr += 6;
 }
 
-// On AddPolyline() and AddConvexPolyFilled() we intentionally avoid using ImVec2 and superflous function calls to optimize debug/non-inlined builds.
+// On AddPolyline() and AddConvexPolyFilled() we intentionally avoid using ImVec2 and superfluous function calls to optimize debug/non-inlined builds.
 // Those macros expects l-values.
 #define IM_NORMALIZE2F_OVER_ZERO(VX,VY)     do { float d2 = VX*VX + VY*VY; if (d2 > 0.0f) { float inv_len = 1.0f / ImSqrt(d2); VX *= inv_len; VY *= inv_len; } } while (0)
 #define IM_FIXNORMAL2F(VX,VY)               do { float d2 = VX*VX + VY*VY; if (d2 < 0.5f) d2 = 0.5f; float inv_lensq = 1.0f / d2; VX *= inv_lensq; VY *= inv_lensq; } while (0)
@@ -684,7 +684,7 @@
                 dm_x *= AA_SIZE;
                 dm_y *= AA_SIZE;
 
-                // Add temporary vertexes
+                // Add temporary vertices
                 ImVec2* out_vtx = &temp_points[i2*2];
                 out_vtx[0].x = points[i2].x + dm_x;
                 out_vtx[0].y = points[i2].y + dm_y;
@@ -701,7 +701,7 @@
                 idx1 = idx2;
             }
 
-            // Add vertexes
+            // Add vertices
             for (int i = 0; i < points_count; i++)
             {
                 _VtxWritePtr[0].pos = points[i];          _VtxWritePtr[0].uv = uv; _VtxWritePtr[0].col = col;
@@ -741,7 +741,7 @@
                 float dm_in_x = dm_x * half_inner_thickness;
                 float dm_in_y = dm_y * half_inner_thickness;
 
-                // Add temporary vertexes
+                // Add temporary vertices
                 ImVec2* out_vtx = &temp_points[i2*4];
                 out_vtx[0].x = points[i2].x + dm_out_x;
                 out_vtx[0].y = points[i2].y + dm_out_y;
@@ -764,7 +764,7 @@
                 idx1 = idx2;
             }
 
-            // Add vertexes
+            // Add vertices
             for (int i = 0; i < points_count; i++)
             {
                 _VtxWritePtr[0].pos = temp_points[i*4+0]; _VtxWritePtr[0].uv = uv; _VtxWritePtr[0].col = col_trans;
@@ -2307,7 +2307,7 @@
 
     // Ellipsis character is required for rendering elided text. We prefer using U+2026 (horizontal ellipsis).
     // However some old fonts may contain ellipsis at U+0085. Here we auto-detect most suitable ellipsis character.
-    // FIXME: Also note that 0x2026 is currently seldomly included in our font ranges. Because of this we are more likely to use three individual dots.
+    // FIXME: Also note that 0x2026 is currently seldom included in our font ranges. Because of this we are more likely to use three individual dots.
     for (int i = 0; i < atlas->Fonts.size(); i++)
     {
         ImFont* font = atlas->Fonts[i];
@@ -3329,7 +3329,7 @@
 
 // Helper for ColorPicker4()
 // NB: This is rather brittle and will show artifact when rounding this enabled if rounded corners overlap multiple cells. Caller currently responsible for avoiding that.
-// Spent a non reasonable amount of time trying to getting this right for ColorButton with rounding+anti-aliasing+ImGuiColorEditFlags_HalfAlphaPreview flag + various grid sizes and offsets, and eventually gave up... probably more reasonable to disable rounding alltogether.
+// Spent a non reasonable amount of time trying to getting this right for ColorButton with rounding+anti-aliasing+ImGuiColorEditFlags_HalfAlphaPreview flag + various grid sizes and offsets, and eventually gave up... probably more reasonable to disable rounding altogether.
 // FIXME: uses ImGui::GetColorU32
 void ImGui::RenderColorRectWithAlphaCheckerboard(ImDrawList* draw_list, ImVec2 p_min, ImVec2 p_max, ImU32 col, float grid_step, ImVec2 grid_off, float rounding, int rounding_corners_flags)
 {
diff --git a/imgui_widgets.cpp b/imgui_widgets.cpp
index 02ac3cd..e58c8ae 100644
--- a/imgui_widgets.cpp
+++ b/imgui_widgets.cpp
@@ -2345,7 +2345,7 @@
     return (float)((FLOATTYPE)(v_clamped - v_min) / (FLOATTYPE)(v_max - v_min));
 }
 
-// FIXME: Move some of the code into SliderBehavior(). Current responsability is larger than what the equivalent DragBehaviorT<> does, we also do some rendering, etc.
+// FIXME: Move some of the code into SliderBehavior(). Current responsibility is larger than what the equivalent DragBehaviorT<> does, we also do some rendering, etc.
 template<typename TYPE, typename SIGNEDTYPE, typename FLOATTYPE>
 bool ImGui::SliderBehaviorT(const ImRect& bb, ImGuiID id, ImGuiDataType data_type, TYPE* v, const TYPE v_min, const TYPE v_max, const char* format, float power, ImGuiSliderFlags flags, ImRect* out_grab_bb)
 {
@@ -2942,7 +2942,7 @@
     if ((flags & (ImGuiInputTextFlags_CharsHexadecimal | ImGuiInputTextFlags_CharsScientific)) == 0)
         flags |= ImGuiInputTextFlags_CharsDecimal;
     flags |= ImGuiInputTextFlags_AutoSelectAll;
-    flags |= ImGuiInputTextFlags_NoMarkEdited;  // We call MarkItemEdited() ourselve by comparing the actual data rather than the string.
+    flags |= ImGuiInputTextFlags_NoMarkEdited;  // We call MarkItemEdited() ourselves by comparing the actual data rather than the string.
 
     if (p_step != NULL)
     {
@@ -3360,7 +3360,7 @@
         if (!is_resizable)
             return;
 
-        // Contrary to STB_TEXTEDIT_INSERTCHARS() this is working in the UTF8 buffer, hence the midly similar code (until we remove the U16 buffer alltogether!)
+        // Contrary to STB_TEXTEDIT_INSERTCHARS() this is working in the UTF8 buffer, hence the mildly similar code (until we remove the U16 buffer altogether!)
         ImGuiContext& g = *GImGui;
         ImGuiInputTextState* edit_state = &g.InputTextState;
         IM_ASSERT(edit_state->ID != 0 && g.ActiveId == edit_state->ID);
@@ -4745,7 +4745,7 @@
         if (flags & ImGuiColorEditFlags_DisplayRGB || (flags & ImGuiColorEditFlags__DisplayMask) == 0)
             if (ColorEdit4("##rgb", col, sub_flags | ImGuiColorEditFlags_DisplayRGB))
             {
-                // FIXME: Hackily differenciating using the DragInt (ActiveId != 0 && !ActiveIdAllowOverlap) vs. using the InputText or DropTarget.
+                // FIXME: Hackily differentiating using the DragInt (ActiveId != 0 && !ActiveIdAllowOverlap) vs. using the InputText or DropTarget.
                 // For the later we don't want to run the hue-wrap canceling code. If you are well versed in HSV picker please provide your input! (See #2050)
                 value_changed_fix_hue_wrap = (g.ActiveId != 0 && !g.ActiveIdAllowOverlap);
                 value_changed = true;
@@ -6249,7 +6249,7 @@
         g.NavWindow = window;  // Odd hack to allow hovering across menus of a same menu-set (otherwise we wouldn't be able to hover parent)
 
     // The reference position stored in popup_pos will be used by Begin() to find a suitable position for the child menu,
-    // However the final position is going to be different! It is choosen by FindBestWindowPosForPopup().
+    // However the final position is going to be different! It is chosen by FindBestWindowPosForPopup().
     // e.g. Menus tend to overlap each other horizontally to amplify relative Z-ordering.
     ImVec2 popup_pos, pos = window->DC.CursorPos;
     if (window->DC.LayoutType == ImGuiLayoutType_Horizontal)