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imgui_widgets.cpp
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// dear imgui, v1.89 WIP
// (widgets code)
/*
Index of this file:
// [SECTION] Forward Declarations
// [SECTION] Widgets: Text, etc.
// [SECTION] Widgets: Main (Button, Image, Checkbox, RadioButton, ProgressBar, Bullet, etc.)
// [SECTION] Widgets: Low-level Layout helpers (Spacing, Dummy, NewLine, Separator, etc.)
// [SECTION] Widgets: ComboBox
// [SECTION] Data Type and Data Formatting Helpers
// [SECTION] Widgets: DragScalar, DragFloat, DragInt, etc.
// [SECTION] Widgets: SliderScalar, SliderFloat, SliderInt, etc.
// [SECTION] Widgets: InputScalar, InputFloat, InputInt, etc.
// [SECTION] Widgets: InputText, InputTextMultiline
// [SECTION] Widgets: ColorEdit, ColorPicker, ColorButton, etc.
// [SECTION] Widgets: TreeNode, CollapsingHeader, etc.
// [SECTION] Widgets: Selectable
// [SECTION] Widgets: ListBox
// [SECTION] Widgets: PlotLines, PlotHistogram
// [SECTION] Widgets: Value helpers
// [SECTION] Widgets: MenuItem, BeginMenu, EndMenu, etc.
// [SECTION] Widgets: BeginTabBar, EndTabBar, etc.
// [SECTION] Widgets: BeginTabItem, EndTabItem, etc.
// [SECTION] Widgets: Columns, BeginColumns, EndColumns, etc.
*/
#if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_WARNINGS)
#define _CRT_SECURE_NO_WARNINGS
#endif
#include "imgui.h"
#ifndef IMGUI_DISABLE
#ifndef IMGUI_DEFINE_MATH_OPERATORS
#define IMGUI_DEFINE_MATH_OPERATORS
#endif
#include "imgui_internal.h"
// System includes
#if defined(_MSC_VER) && _MSC_VER <= 1500 // MSVC 2008 or earlier
#include <stddef.h> // intptr_t
#else
#include <stdint.h> // intptr_t
#endif
//-------------------------------------------------------------------------
// Warnings
//-------------------------------------------------------------------------
// Visual Studio warnings
#ifdef _MSC_VER
#pragma warning (disable: 4127) // condition expression is constant
#pragma warning (disable: 4996) // 'This function or variable may be unsafe': strcpy, strdup, sprintf, vsnprintf, sscanf, fopen
#if defined(_MSC_VER) && _MSC_VER >= 1922 // MSVC 2019 16.2 or later
#pragma warning (disable: 5054) // operator '|': deprecated between enumerations of different types
#endif
#pragma warning (disable: 26451) // [Static Analyzer] Arithmetic overflow : Using operator 'xxx' on a 4 byte value and then casting the result to a 8 byte value. Cast the value to the wider type before calling operator 'xxx' to avoid overflow(io.2).
#pragma warning (disable: 26812) // [Static Analyzer] The enum type 'xxx' is unscoped. Prefer 'enum class' over 'enum' (Enum.3).
#endif
// Clang/GCC warnings with -Weverything
#if defined(__clang__)
#if __has_warning("-Wunknown-warning-option")
#pragma clang diagnostic ignored "-Wunknown-warning-option" // warning: unknown warning group 'xxx' // not all warnings are known by all Clang versions and they tend to be rename-happy.. so ignoring warnings triggers new warnings on some configuration. Great!
#endif
#pragma clang diagnostic ignored "-Wunknown-pragmas" // warning: unknown warning group 'xxx'
#pragma clang diagnostic ignored "-Wold-style-cast" // warning: use of old-style cast // yes, they are more terse.
#pragma clang diagnostic ignored "-Wfloat-equal" // warning: comparing floating point with == or != is unsafe // storing and comparing against same constants (typically 0.0f) is ok.
#pragma clang diagnostic ignored "-Wformat-nonliteral" // warning: format string is not a string literal // passing non-literal to vsnformat(). yes, user passing incorrect format strings can crash the code.
#pragma clang diagnostic ignored "-Wsign-conversion" // warning: implicit conversion changes signedness
#pragma clang diagnostic ignored "-Wzero-as-null-pointer-constant" // warning: zero as null pointer constant // some standard header variations use #define NULL 0
#pragma clang diagnostic ignored "-Wdouble-promotion" // warning: implicit conversion from 'float' to 'double' when passing argument to function // using printf() is a misery with this as C++ va_arg ellipsis changes float to double.
#pragma clang diagnostic ignored "-Wenum-enum-conversion" // warning: bitwise operation between different enumeration types ('XXXFlags_' and 'XXXFlagsPrivate_')
#pragma clang diagnostic ignored "-Wdeprecated-enum-enum-conversion"// warning: bitwise operation between different enumeration types ('XXXFlags_' and 'XXXFlagsPrivate_') is deprecated
#pragma clang diagnostic ignored "-Wimplicit-int-float-conversion" // warning: implicit conversion from 'xxx' to 'float' may lose precision
#elif defined(__GNUC__)
#pragma GCC diagnostic ignored "-Wpragmas" // warning: unknown option after '#pragma GCC diagnostic' kind
#pragma GCC diagnostic ignored "-Wformat-nonliteral" // warning: format not a string literal, format string not checked
#pragma GCC diagnostic ignored "-Wclass-memaccess" // [__GNUC__ >= 8] warning: 'memset/memcpy' clearing/writing an object of type 'xxxx' with no trivial copy-assignment; use assignment or value-initialization instead
#pragma GCC diagnostic ignored "-Wdeprecated-enum-enum-conversion" // warning: bitwise operation between different enumeration types ('XXXFlags_' and 'XXXFlagsPrivate_') is deprecated
#endif
//-------------------------------------------------------------------------
// Data
//-------------------------------------------------------------------------
// Widgets
static const float DRAGDROP_HOLD_TO_OPEN_TIMER = 0.70f; // Time for drag-hold to activate items accepting the ImGuiButtonFlags_PressedOnDragDropHold button behavior.
static const float DRAG_MOUSE_THRESHOLD_FACTOR = 0.50f; // Multiplier for the default value of io.MouseDragThreshold to make DragFloat/DragInt react faster to mouse drags.
// Those MIN/MAX values are not define because we need to point to them
static const signed char IM_S8_MIN = -128;
static const signed char IM_S8_MAX = 127;
static const unsigned char IM_U8_MIN = 0;
static const unsigned char IM_U8_MAX = 0xFF;
static const signed short IM_S16_MIN = -32768;
static const signed short IM_S16_MAX = 32767;
static const unsigned short IM_U16_MIN = 0;
static const unsigned short IM_U16_MAX = 0xFFFF;
static const ImS32 IM_S32_MIN = INT_MIN; // (-2147483647 - 1), (0x80000000);
static const ImS32 IM_S32_MAX = INT_MAX; // (2147483647), (0x7FFFFFFF)
static const ImU32 IM_U32_MIN = 0;
static const ImU32 IM_U32_MAX = UINT_MAX; // (0xFFFFFFFF)
#ifdef LLONG_MIN
static const ImS64 IM_S64_MIN = LLONG_MIN; // (-9223372036854775807ll - 1ll);
static const ImS64 IM_S64_MAX = LLONG_MAX; // (9223372036854775807ll);
#else
static const ImS64 IM_S64_MIN = -9223372036854775807LL - 1;
static const ImS64 IM_S64_MAX = 9223372036854775807LL;
#endif
static const ImU64 IM_U64_MIN = 0;
#ifdef ULLONG_MAX
static const ImU64 IM_U64_MAX = ULLONG_MAX; // (0xFFFFFFFFFFFFFFFFull);
#else
static const ImU64 IM_U64_MAX = (2ULL * 9223372036854775807LL + 1);
#endif
//-------------------------------------------------------------------------
// [SECTION] Forward Declarations
//-------------------------------------------------------------------------
// For InputTextEx()
static bool InputTextFilterCharacter(unsigned int* p_char, ImGuiInputTextFlags flags, ImGuiInputTextCallback callback, void* user_data, ImGuiInputSource input_source);
static int InputTextCalcTextLenAndLineCount(const char* text_begin, const char** out_text_end);
static ImVec2 InputTextCalcTextSizeW(const ImWchar* text_begin, const ImWchar* text_end, const ImWchar** remaining = NULL, ImVec2* out_offset = NULL, bool stop_on_new_line = false);
//-------------------------------------------------------------------------
// [SECTION] Widgets: Text, etc.
//-------------------------------------------------------------------------
// - TextEx() [Internal]
// - TextUnformatted()
// - Text()
// - TextV()
// - TextColored()
// - TextColoredV()
// - TextDisabled()
// - TextDisabledV()
// - TextWrapped()
// - TextWrappedV()
// - LabelText()
// - LabelTextV()
// - BulletText()
// - BulletTextV()
//-------------------------------------------------------------------------
void ImGui::TextEx(const char* text, const char* text_end, ImGuiTextFlags flags)
{
ImGuiWindow* window = GetCurrentWindow();
if (window->SkipItems)
return;
ImGuiContext& g = *GImGui;
// Accept null ranges
if (text == text_end)
text = text_end = "";
// Calculate length
const char* text_begin = text;
if (text_end == NULL)
text_end = text + strlen(text); // FIXME-OPT
const ImVec2 text_pos(window->DC.CursorPos.x, window->DC.CursorPos.y + window->DC.CurrLineTextBaseOffset);
const float wrap_pos_x = window->DC.TextWrapPos;
const bool wrap_enabled = (wrap_pos_x >= 0.0f);
if (text_end - text <= 2000 || wrap_enabled)
{
// Common case
const float wrap_width = wrap_enabled ? CalcWrapWidthForPos(window->DC.CursorPos, wrap_pos_x) : 0.0f;
const ImVec2 text_size = CalcTextSize(text_begin, text_end, false, wrap_width);
ImRect bb(text_pos, text_pos + text_size);
ItemSize(text_size, 0.0f);
if (!ItemAdd(bb, 0))
return;
// Render (we don't hide text after ## in this end-user function)
RenderTextWrapped(bb.Min, text_begin, text_end, wrap_width);
}
else
{
// Long text!
// Perform manual coarse clipping to optimize for long multi-line text
// - From this point we will only compute the width of lines that are visible. Optimization only available when word-wrapping is disabled.
// - We also don't vertically center the text within the line full height, which is unlikely to matter because we are likely the biggest and only item on the line.
// - We use memchr(), pay attention that well optimized versions of those str/mem functions are much faster than a casually written loop.
const char* line = text;
const float line_height = GetTextLineHeight();
ImVec2 text_size(0, 0);
// Lines to skip (can't skip when logging text)
ImVec2 pos = text_pos;
if (!g.LogEnabled)
{
int lines_skippable = (int)((window->ClipRect.Min.y - text_pos.y) / line_height);
if (lines_skippable > 0)
{
int lines_skipped = 0;
while (line < text_end && lines_skipped < lines_skippable)
{
const char* line_end = (const char*)memchr(line, '\n', text_end - line);
if (!line_end)
line_end = text_end;
if ((flags & ImGuiTextFlags_NoWidthForLargeClippedText) == 0)
text_size.x = ImMax(text_size.x, CalcTextSize(line, line_end).x);
line = line_end + 1;
lines_skipped++;
}
pos.y += lines_skipped * line_height;
}
}
// Lines to render
if (line < text_end)
{
ImRect line_rect(pos, pos + ImVec2(FLT_MAX, line_height));
while (line < text_end)
{
if (IsClippedEx(line_rect, 0))
break;
const char* line_end = (const char*)memchr(line, '\n', text_end - line);
if (!line_end)
line_end = text_end;
text_size.x = ImMax(text_size.x, CalcTextSize(line, line_end).x);
RenderText(pos, line, line_end, false);
line = line_end + 1;
line_rect.Min.y += line_height;
line_rect.Max.y += line_height;
pos.y += line_height;
}
// Count remaining lines
int lines_skipped = 0;
while (line < text_end)
{
const char* line_end = (const char*)memchr(line, '\n', text_end - line);
if (!line_end)
line_end = text_end;
if ((flags & ImGuiTextFlags_NoWidthForLargeClippedText) == 0)
text_size.x = ImMax(text_size.x, CalcTextSize(line, line_end).x);
line = line_end + 1;
lines_skipped++;
}
pos.y += lines_skipped * line_height;
}
text_size.y = (pos - text_pos).y;
ImRect bb(text_pos, text_pos + text_size);
ItemSize(text_size, 0.0f);
ItemAdd(bb, 0);
}
}
void ImGui::TextUnformatted(const char* text, const char* text_end)
{
TextEx(text, text_end, ImGuiTextFlags_NoWidthForLargeClippedText);
}
void ImGui::Text(const char* fmt, ...)
{
va_list args;
va_start(args, fmt);
TextV(fmt, args);
va_end(args);
}
void ImGui::TextV(const char* fmt, va_list args)
{
ImGuiWindow* window = GetCurrentWindow();
if (window->SkipItems)
return;
// FIXME-OPT: Handle the %s shortcut?
const char* text, *text_end;
ImFormatStringToTempBufferV(&text, &text_end, fmt, args);
TextEx(text, text_end, ImGuiTextFlags_NoWidthForLargeClippedText);
}
void ImGui::TextColored(const ImVec4& col, const char* fmt, ...)
{
va_list args;
va_start(args, fmt);
TextColoredV(col, fmt, args);
va_end(args);
}
void ImGui::TextColoredV(const ImVec4& col, const char* fmt, va_list args)
{
PushStyleColor(ImGuiCol_Text, col);
if (fmt[0] == '%' && fmt[1] == 's' && fmt[2] == 0)
TextEx(va_arg(args, const char*), NULL, ImGuiTextFlags_NoWidthForLargeClippedText); // Skip formatting
else
TextV(fmt, args);
PopStyleColor();
}
void ImGui::TextDisabled(const char* fmt, ...)
{
va_list args;
va_start(args, fmt);
TextDisabledV(fmt, args);
va_end(args);
}
void ImGui::TextDisabledV(const char* fmt, va_list args)
{
ImGuiContext& g = *GImGui;
PushStyleColor(ImGuiCol_Text, g.Style.Colors[ImGuiCol_TextDisabled]);
if (fmt[0] == '%' && fmt[1] == 's' && fmt[2] == 0)
TextEx(va_arg(args, const char*), NULL, ImGuiTextFlags_NoWidthForLargeClippedText); // Skip formatting
else
TextV(fmt, args);
PopStyleColor();
}
void ImGui::TextWrapped(const char* fmt, ...)
{
va_list args;
va_start(args, fmt);
TextWrappedV(fmt, args);
va_end(args);
}
void ImGui::TextWrappedV(const char* fmt, va_list args)
{
ImGuiContext& g = *GImGui;
bool need_backup = (g.CurrentWindow->DC.TextWrapPos < 0.0f); // Keep existing wrap position if one is already set
if (need_backup)
PushTextWrapPos(0.0f);
if (fmt[0] == '%' && fmt[1] == 's' && fmt[2] == 0)
TextEx(va_arg(args, const char*), NULL, ImGuiTextFlags_NoWidthForLargeClippedText); // Skip formatting
else
TextV(fmt, args);
if (need_backup)
PopTextWrapPos();
}
void ImGui::LabelText(const char* label, const char* fmt, ...)
{
va_list args;
va_start(args, fmt);
LabelTextV(label, fmt, args);
va_end(args);
}
// Add a label+text combo aligned to other label+value widgets
void ImGui::LabelTextV(const char* label, const char* fmt, va_list args)
{
ImGuiWindow* window = GetCurrentWindow();
if (window->SkipItems)
return;
ImGuiContext& g = *GImGui;
const ImGuiStyle& style = g.Style;
const float w = CalcItemWidth();
const char* value_text_begin, *value_text_end;
ImFormatStringToTempBufferV(&value_text_begin, &value_text_end, fmt, args);
const ImVec2 value_size = CalcTextSize(value_text_begin, value_text_end, false);
const ImVec2 label_size = CalcTextSize(label, NULL, true);
const ImVec2 pos = window->DC.CursorPos;
const ImRect value_bb(pos, pos + ImVec2(w, value_size.y + style.FramePadding.y * 2));
const ImRect total_bb(pos, pos + ImVec2(w + (label_size.x > 0.0f ? style.ItemInnerSpacing.x + label_size.x : 0.0f), ImMax(value_size.y, label_size.y) + style.FramePadding.y * 2));
ItemSize(total_bb, style.FramePadding.y);
if (!ItemAdd(total_bb, 0))
return;
// Render
RenderTextClipped(value_bb.Min + style.FramePadding, value_bb.Max, value_text_begin, value_text_end, &value_size, ImVec2(0.0f, 0.0f));
if (label_size.x > 0.0f)
RenderText(ImVec2(value_bb.Max.x + style.ItemInnerSpacing.x, value_bb.Min.y + style.FramePadding.y), label);
}
void ImGui::BulletText(const char* fmt, ...)
{
va_list args;
va_start(args, fmt);
BulletTextV(fmt, args);
va_end(args);
}
// Text with a little bullet aligned to the typical tree node.
void ImGui::BulletTextV(const char* fmt, va_list args)
{
ImGuiWindow* window = GetCurrentWindow();
if (window->SkipItems)
return;
ImGuiContext& g = *GImGui;
const ImGuiStyle& style = g.Style;
const char* text_begin, *text_end;
ImFormatStringToTempBufferV(&text_begin, &text_end, fmt, args);
const ImVec2 label_size = CalcTextSize(text_begin, text_end, false);
const ImVec2 total_size = ImVec2(g.FontSize + (label_size.x > 0.0f ? (label_size.x + style.FramePadding.x * 2) : 0.0f), label_size.y); // Empty text doesn't add padding
ImVec2 pos = window->DC.CursorPos;
pos.y += window->DC.CurrLineTextBaseOffset;
ItemSize(total_size, 0.0f);
const ImRect bb(pos, pos + total_size);
if (!ItemAdd(bb, 0))
return;
// Render
ImU32 text_col = GetColorU32(ImGuiCol_Text);
RenderBullet(window->DrawList, bb.Min + ImVec2(style.FramePadding.x + g.FontSize * 0.5f, g.FontSize * 0.5f), text_col);
RenderText(bb.Min + ImVec2(g.FontSize + style.FramePadding.x * 2, 0.0f), text_begin, text_end, false);
}
//-------------------------------------------------------------------------
// [SECTION] Widgets: Main
//-------------------------------------------------------------------------
// - ButtonBehavior() [Internal]
// - Button()
// - SmallButton()
// - InvisibleButton()
// - ArrowButton()
// - CloseButton() [Internal]
// - CollapseButton() [Internal]
// - GetWindowScrollbarID() [Internal]
// - GetWindowScrollbarRect() [Internal]
// - Scrollbar() [Internal]
// - ScrollbarEx() [Internal]
// - Image()
// - ImageButton()
// - Checkbox()
// - CheckboxFlagsT() [Internal]
// - CheckboxFlags()
// - RadioButton()
// - ProgressBar()
// - Bullet()
//-------------------------------------------------------------------------
// The ButtonBehavior() function is key to many interactions and used by many/most widgets.
// Because we handle so many cases (keyboard/gamepad navigation, drag and drop) and many specific behavior (via ImGuiButtonFlags_),
// this code is a little complex.
// By far the most common path is interacting with the Mouse using the default ImGuiButtonFlags_PressedOnClickRelease button behavior.
// See the series of events below and the corresponding state reported by dear imgui:
//------------------------------------------------------------------------------------------------------------------------------------------------
// with PressedOnClickRelease: return-value IsItemHovered() IsItemActive() IsItemActivated() IsItemDeactivated() IsItemClicked()
// Frame N+0 (mouse is outside bb) - - - - - -
// Frame N+1 (mouse moves inside bb) - true - - - -
// Frame N+2 (mouse button is down) - true true true - true
// Frame N+3 (mouse button is down) - true true - - -
// Frame N+4 (mouse moves outside bb) - - true - - -
// Frame N+5 (mouse moves inside bb) - true true - - -
// Frame N+6 (mouse button is released) true true - - true -
// Frame N+7 (mouse button is released) - true - - - -
// Frame N+8 (mouse moves outside bb) - - - - - -
//------------------------------------------------------------------------------------------------------------------------------------------------
// with PressedOnClick: return-value IsItemHovered() IsItemActive() IsItemActivated() IsItemDeactivated() IsItemClicked()
// Frame N+2 (mouse button is down) true true true true - true
// Frame N+3 (mouse button is down) - true true - - -
// Frame N+6 (mouse button is released) - true - - true -
// Frame N+7 (mouse button is released) - true - - - -
//------------------------------------------------------------------------------------------------------------------------------------------------
// with PressedOnRelease: return-value IsItemHovered() IsItemActive() IsItemActivated() IsItemDeactivated() IsItemClicked()
// Frame N+2 (mouse button is down) - true - - - true
// Frame N+3 (mouse button is down) - true - - - -
// Frame N+6 (mouse button is released) true true - - - -
// Frame N+7 (mouse button is released) - true - - - -
//------------------------------------------------------------------------------------------------------------------------------------------------
// with PressedOnDoubleClick: return-value IsItemHovered() IsItemActive() IsItemActivated() IsItemDeactivated() IsItemClicked()
// Frame N+0 (mouse button is down) - true - - - true
// Frame N+1 (mouse button is down) - true - - - -
// Frame N+2 (mouse button is released) - true - - - -
// Frame N+3 (mouse button is released) - true - - - -
// Frame N+4 (mouse button is down) true true true true - true
// Frame N+5 (mouse button is down) - true true - - -
// Frame N+6 (mouse button is released) - true - - true -
// Frame N+7 (mouse button is released) - true - - - -
//------------------------------------------------------------------------------------------------------------------------------------------------
// Note that some combinations are supported,
// - PressedOnDragDropHold can generally be associated with any flag.
// - PressedOnDoubleClick can be associated by PressedOnClickRelease/PressedOnRelease, in which case the second release event won't be reported.
//------------------------------------------------------------------------------------------------------------------------------------------------
// The behavior of the return-value changes when ImGuiButtonFlags_Repeat is set:
// Repeat+ Repeat+ Repeat+ Repeat+
// PressedOnClickRelease PressedOnClick PressedOnRelease PressedOnDoubleClick
//-------------------------------------------------------------------------------------------------------------------------------------------------
// Frame N+0 (mouse button is down) - true - true
// ... - - - -
// Frame N + RepeatDelay true true - true
// ... - - - -
// Frame N + RepeatDelay + RepeatRate*N true true - true
//-------------------------------------------------------------------------------------------------------------------------------------------------
bool ImGui::ButtonBehavior(const ImRect& bb, ImGuiID id, bool* out_hovered, bool* out_held, ImGuiButtonFlags flags)
{
ImGuiContext& g = *GImGui;
ImGuiWindow* window = GetCurrentWindow();
// Default only reacts to left mouse button
if ((flags & ImGuiButtonFlags_MouseButtonMask_) == 0)
flags |= ImGuiButtonFlags_MouseButtonDefault_;
// Default behavior requires click + release inside bounding box
if ((flags & ImGuiButtonFlags_PressedOnMask_) == 0)
flags |= ImGuiButtonFlags_PressedOnDefault_;
ImGuiWindow* backup_hovered_window = g.HoveredWindow;
const bool flatten_hovered_children = (flags & ImGuiButtonFlags_FlattenChildren) && g.HoveredWindow && g.HoveredWindow->RootWindow == window;
if (flatten_hovered_children)
g.HoveredWindow = window;
#ifdef IMGUI_ENABLE_TEST_ENGINE
if (id != 0 && g.LastItemData.ID != id)
IMGUI_TEST_ENGINE_ITEM_ADD(bb, id);
#endif
bool pressed = false;
bool hovered = ItemHoverable(bb, id);
// Drag source doesn't report as hovered
if (hovered && g.DragDropActive && g.DragDropPayload.SourceId == id && !(g.DragDropSourceFlags & ImGuiDragDropFlags_SourceNoDisableHover))
hovered = false;
// Special mode for Drag and Drop where holding button pressed for a long time while dragging another item triggers the button
if (g.DragDropActive && (flags & ImGuiButtonFlags_PressedOnDragDropHold) && !(g.DragDropSourceFlags & ImGuiDragDropFlags_SourceNoHoldToOpenOthers))
if (IsItemHovered(ImGuiHoveredFlags_AllowWhenBlockedByActiveItem))
{
hovered = true;
SetHoveredID(id);
if (g.HoveredIdTimer - g.IO.DeltaTime <= DRAGDROP_HOLD_TO_OPEN_TIMER && g.HoveredIdTimer >= DRAGDROP_HOLD_TO_OPEN_TIMER)
{
pressed = true;
g.DragDropHoldJustPressedId = id;
FocusWindow(window);
}
}
if (flatten_hovered_children)
g.HoveredWindow = backup_hovered_window;
// AllowOverlap mode (rarely used) requires previous frame HoveredId to be null or to match. This allows using patterns where a later submitted widget overlaps a previous one.
if (hovered && (flags & ImGuiButtonFlags_AllowItemOverlap) && (g.HoveredIdPreviousFrame != id && g.HoveredIdPreviousFrame != 0))
hovered = false;
// Mouse handling
if (hovered)
{
if (!(flags & ImGuiButtonFlags_NoKeyModifiers) || (!g.IO.KeyCtrl && !g.IO.KeyShift && !g.IO.KeyAlt))
{
// Poll buttons
int mouse_button_clicked = -1;
if ((flags & ImGuiButtonFlags_MouseButtonLeft) && g.IO.MouseClicked[0]) { mouse_button_clicked = 0; }
else if ((flags & ImGuiButtonFlags_MouseButtonRight) && g.IO.MouseClicked[1]) { mouse_button_clicked = 1; }
else if ((flags & ImGuiButtonFlags_MouseButtonMiddle) && g.IO.MouseClicked[2]) { mouse_button_clicked = 2; }
if (mouse_button_clicked != -1 && g.ActiveId != id)
{
if (flags & (ImGuiButtonFlags_PressedOnClickRelease | ImGuiButtonFlags_PressedOnClickReleaseAnywhere))
{
SetActiveID(id, window);
g.ActiveIdMouseButton = mouse_button_clicked;
if (!(flags & ImGuiButtonFlags_NoNavFocus))
SetFocusID(id, window);
FocusWindow(window);
}
if ((flags & ImGuiButtonFlags_PressedOnClick) || ((flags & ImGuiButtonFlags_PressedOnDoubleClick) && g.IO.MouseClickedCount[mouse_button_clicked] == 2))
{
pressed = true;
if (flags & ImGuiButtonFlags_NoHoldingActiveId)
ClearActiveID();
else
SetActiveID(id, window); // Hold on ID
if (!(flags & ImGuiButtonFlags_NoNavFocus))
SetFocusID(id, window);
g.ActiveIdMouseButton = mouse_button_clicked;
FocusWindow(window);
}
}
if (flags & ImGuiButtonFlags_PressedOnRelease)
{
int mouse_button_released = -1;
if ((flags & ImGuiButtonFlags_MouseButtonLeft) && g.IO.MouseReleased[0]) { mouse_button_released = 0; }
else if ((flags & ImGuiButtonFlags_MouseButtonRight) && g.IO.MouseReleased[1]) { mouse_button_released = 1; }
else if ((flags & ImGuiButtonFlags_MouseButtonMiddle) && g.IO.MouseReleased[2]) { mouse_button_released = 2; }
if (mouse_button_released != -1)
{
const bool has_repeated_at_least_once = (flags & ImGuiButtonFlags_Repeat) && g.IO.MouseDownDurationPrev[mouse_button_released] >= g.IO.KeyRepeatDelay; // Repeat mode trumps on release behavior
if (!has_repeated_at_least_once)
pressed = true;
if (!(flags & ImGuiButtonFlags_NoNavFocus))
SetFocusID(id, window);
ClearActiveID();
}
}
// 'Repeat' mode acts when held regardless of _PressedOn flags (see table above).
// Relies on repeat logic of IsMouseClicked() but we may as well do it ourselves if we end up exposing finer RepeatDelay/RepeatRate settings.
if (g.ActiveId == id && (flags & ImGuiButtonFlags_Repeat))
if (g.IO.MouseDownDuration[g.ActiveIdMouseButton] > 0.0f && IsMouseClicked(g.ActiveIdMouseButton, true))
pressed = true;
}
if (pressed)
g.NavDisableHighlight = true;
}
// Gamepad/Keyboard navigation
// We report navigated item as hovered but we don't set g.HoveredId to not interfere with mouse.
if (g.NavId == id && !g.NavDisableHighlight && g.NavDisableMouseHover && (g.ActiveId == 0 || g.ActiveId == id || g.ActiveId == window->MoveId))
if (!(flags & ImGuiButtonFlags_NoHoveredOnFocus))
hovered = true;
if (g.NavActivateDownId == id)
{
bool nav_activated_by_code = (g.NavActivateId == id);
bool nav_activated_by_inputs = (g.NavActivatePressedId == id);
if (!nav_activated_by_inputs && (flags & ImGuiButtonFlags_Repeat))
{
// Avoid pressing both keys from triggering double amount of repeat events
const ImGuiKeyData* key1 = GetKeyData(ImGuiKey_Space);
const ImGuiKeyData* key2 = GetKeyData(ImGuiKey_NavGamepadActivate);
const float t1 = ImMax(key1->DownDuration, key2->DownDuration);
nav_activated_by_inputs = CalcTypematicRepeatAmount(t1 - g.IO.DeltaTime, t1, g.IO.KeyRepeatDelay, g.IO.KeyRepeatRate) > 0;
}
if (nav_activated_by_code || nav_activated_by_inputs)
{
// Set active id so it can be queried by user via IsItemActive(), equivalent of holding the mouse button.
pressed = true;
SetActiveID(id, window);
g.ActiveIdSource = ImGuiInputSource_Nav;
if (!(flags & ImGuiButtonFlags_NoNavFocus))
SetFocusID(id, window);
}
}
// Process while held
bool held = false;
if (g.ActiveId == id)
{
if (g.ActiveIdSource == ImGuiInputSource_Mouse)
{
if (g.ActiveIdIsJustActivated)
g.ActiveIdClickOffset = g.IO.MousePos - bb.Min;
const int mouse_button = g.ActiveIdMouseButton;
IM_ASSERT(mouse_button >= 0 && mouse_button < ImGuiMouseButton_COUNT);
if (g.IO.MouseDown[mouse_button])
{
held = true;
}
else
{
bool release_in = hovered && (flags & ImGuiButtonFlags_PressedOnClickRelease) != 0;
bool release_anywhere = (flags & ImGuiButtonFlags_PressedOnClickReleaseAnywhere) != 0;
if ((release_in || release_anywhere) && !g.DragDropActive)
{
// Report as pressed when releasing the mouse (this is the most common path)
bool is_double_click_release = (flags & ImGuiButtonFlags_PressedOnDoubleClick) && g.IO.MouseReleased[mouse_button] && g.IO.MouseClickedLastCount[mouse_button] == 2;
bool is_repeating_already = (flags & ImGuiButtonFlags_Repeat) && g.IO.MouseDownDurationPrev[mouse_button] >= g.IO.KeyRepeatDelay; // Repeat mode trumps <on release>
if (!is_double_click_release && !is_repeating_already)
pressed = true;
}
ClearActiveID();
}
if (!(flags & ImGuiButtonFlags_NoNavFocus))
g.NavDisableHighlight = true;
}
else if (g.ActiveIdSource == ImGuiInputSource_Nav)
{
// When activated using Nav, we hold on the ActiveID until activation button is released
if (g.NavActivateDownId != id)
ClearActiveID();
}
if (pressed)
g.ActiveIdHasBeenPressedBefore = true;
}
if (out_hovered) *out_hovered = hovered;
if (out_held) *out_held = held;
return pressed;
}
bool ImGui::ButtonEx(const char* label, const ImVec2& size_arg, ImGuiButtonFlags flags)
{
ImGuiWindow* window = GetCurrentWindow();
if (window->SkipItems)
return false;
ImGuiContext& g = *GImGui;
const ImGuiStyle& style = g.Style;
const ImGuiID id = window->GetID(label);
const ImVec2 label_size = CalcTextSize(label, NULL, true);
ImVec2 pos = window->DC.CursorPos;
if ((flags & ImGuiButtonFlags_AlignTextBaseLine) && style.FramePadding.y < window->DC.CurrLineTextBaseOffset) // Try to vertically align buttons that are smaller/have no padding so that text baseline matches (bit hacky, since it shouldn't be a flag)
pos.y += window->DC.CurrLineTextBaseOffset - style.FramePadding.y;
ImVec2 size = CalcItemSize(size_arg, label_size.x + style.FramePadding.x * 2.0f, label_size.y + style.FramePadding.y * 2.0f);
const ImRect bb(pos, pos + size);
ItemSize(size, style.FramePadding.y);
if (!ItemAdd(bb, id))
return false;
if (g.LastItemData.InFlags & ImGuiItemFlags_ButtonRepeat)
flags |= ImGuiButtonFlags_Repeat;
bool hovered, held;
bool pressed = ButtonBehavior(bb, id, &hovered, &held, flags);
// Render
const ImU32 col = GetColorU32((held && hovered) ? ImGuiCol_ButtonActive : hovered ? ImGuiCol_ButtonHovered : ImGuiCol_Button);
RenderNavHighlight(bb, id);
RenderFrame(bb.Min, bb.Max, col, true, style.FrameRounding);
if (g.LogEnabled)
LogSetNextTextDecoration("[", "]");
RenderTextClipped(bb.Min + style.FramePadding, bb.Max - style.FramePadding, label, NULL, &label_size, style.ButtonTextAlign, &bb);
// Automatically close popups
//if (pressed && !(flags & ImGuiButtonFlags_DontClosePopups) && (window->Flags & ImGuiWindowFlags_Popup))
// CloseCurrentPopup();
IMGUI_TEST_ENGINE_ITEM_INFO(id, label, g.LastItemData.StatusFlags);
return pressed;
}
bool ImGui::Button(const char* label, const ImVec2& size_arg)
{
return ButtonEx(label, size_arg, ImGuiButtonFlags_None);
}
// Small buttons fits within text without additional vertical spacing.
bool ImGui::SmallButton(const char* label)
{
ImGuiContext& g = *GImGui;
float backup_padding_y = g.Style.FramePadding.y;
g.Style.FramePadding.y = 0.0f;
bool pressed = ButtonEx(label, ImVec2(0, 0), ImGuiButtonFlags_AlignTextBaseLine);
g.Style.FramePadding.y = backup_padding_y;
return pressed;
}
// Tip: use ImGui::PushID()/PopID() to push indices or pointers in the ID stack.
// Then you can keep 'str_id' empty or the same for all your buttons (instead of creating a string based on a non-string id)
bool ImGui::InvisibleButton(const char* str_id, const ImVec2& size_arg, ImGuiButtonFlags flags)
{
ImGuiContext& g = *GImGui;
ImGuiWindow* window = GetCurrentWindow();
if (window->SkipItems)
return false;
// Cannot use zero-size for InvisibleButton(). Unlike Button() there is not way to fallback using the label size.
IM_ASSERT(size_arg.x != 0.0f && size_arg.y != 0.0f);
const ImGuiID id = window->GetID(str_id);
ImVec2 size = CalcItemSize(size_arg, 0.0f, 0.0f);
const ImRect bb(window->DC.CursorPos, window->DC.CursorPos + size);
ItemSize(size);
if (!ItemAdd(bb, id))
return false;
bool hovered, held;
bool pressed = ButtonBehavior(bb, id, &hovered, &held, flags);
IMGUI_TEST_ENGINE_ITEM_INFO(id, str_id, g.LastItemData.StatusFlags);
return pressed;
}
bool ImGui::ArrowButtonEx(const char* str_id, ImGuiDir dir, ImVec2 size, ImGuiButtonFlags flags)
{
ImGuiContext& g = *GImGui;
ImGuiWindow* window = GetCurrentWindow();
if (window->SkipItems)
return false;
const ImGuiID id = window->GetID(str_id);
const ImRect bb(window->DC.CursorPos, window->DC.CursorPos + size);
const float default_size = GetFrameHeight();
ItemSize(size, (size.y >= default_size) ? g.Style.FramePadding.y : -1.0f);
if (!ItemAdd(bb, id))
return false;
if (g.LastItemData.InFlags & ImGuiItemFlags_ButtonRepeat)
flags |= ImGuiButtonFlags_Repeat;
bool hovered, held;
bool pressed = ButtonBehavior(bb, id, &hovered, &held, flags);
// Render
const ImU32 bg_col = GetColorU32((held && hovered) ? ImGuiCol_ButtonActive : hovered ? ImGuiCol_ButtonHovered : ImGuiCol_Button);
const ImU32 text_col = GetColorU32(ImGuiCol_Text);
RenderNavHighlight(bb, id);
RenderFrame(bb.Min, bb.Max, bg_col, true, g.Style.FrameRounding);
RenderArrow(window->DrawList, bb.Min + ImVec2(ImMax(0.0f, (size.x - g.FontSize) * 0.5f), ImMax(0.0f, (size.y - g.FontSize) * 0.5f)), text_col, dir);
IMGUI_TEST_ENGINE_ITEM_INFO(id, str_id, g.LastItemData.StatusFlags);
return pressed;
}
bool ImGui::ArrowButton(const char* str_id, ImGuiDir dir)
{
float sz = GetFrameHeight();
return ArrowButtonEx(str_id, dir, ImVec2(sz, sz), ImGuiButtonFlags_None);
}
// Button to close a window
bool ImGui::CloseButton(ImGuiID id, const ImVec2& pos)
{
ImGuiContext& g = *GImGui;
ImGuiWindow* window = g.CurrentWindow;
// Tweak 1: Shrink hit-testing area if button covers an abnormally large proportion of the visible region. That's in order to facilitate moving the window away. (#3825)
// This may better be applied as a general hit-rect reduction mechanism for all widgets to ensure the area to move window is always accessible?
const ImRect bb(pos, pos + ImVec2(g.FontSize, g.FontSize) + g.Style.FramePadding * 2.0f);
ImRect bb_interact = bb;
const float area_to_visible_ratio = window->OuterRectClipped.GetArea() / bb.GetArea();
if (area_to_visible_ratio < 1.5f)
bb_interact.Expand(ImFloor(bb_interact.GetSize() * -0.25f));
// Tweak 2: We intentionally allow interaction when clipped so that a mechanical Alt,Right,Activate sequence can always close a window.
// (this isn't the regular behavior of buttons, but it doesn't affect the user much because navigation tends to keep items visible).
bool is_clipped = !ItemAdd(bb_interact, id);
bool hovered, held;
bool pressed = ButtonBehavior(bb_interact, id, &hovered, &held);
if (is_clipped)
return pressed;
// Render
// FIXME: Clarify this mess
ImU32 col = GetColorU32(held ? ImGuiCol_ButtonActive : ImGuiCol_ButtonHovered);
ImVec2 center = bb.GetCenter();
if (hovered)
window->DrawList->AddCircleFilled(center, ImMax(2.0f, g.FontSize * 0.5f + 1.0f), col, 12);
float cross_extent = g.FontSize * 0.5f * 0.7071f - 1.0f;
ImU32 cross_col = GetColorU32(ImGuiCol_Text);
center -= ImVec2(0.5f, 0.5f);
window->DrawList->AddLine(center + ImVec2(+cross_extent, +cross_extent), center + ImVec2(-cross_extent, -cross_extent), cross_col, 1.0f);
window->DrawList->AddLine(center + ImVec2(+cross_extent, -cross_extent), center + ImVec2(-cross_extent, +cross_extent), cross_col, 1.0f);
return pressed;
}
bool ImGui::CollapseButton(ImGuiID id, const ImVec2& pos)
{
ImGuiContext& g = *GImGui;
ImGuiWindow* window = g.CurrentWindow;
ImRect bb(pos, pos + ImVec2(g.FontSize, g.FontSize) + g.Style.FramePadding * 2.0f);
ItemAdd(bb, id);
bool hovered, held;
bool pressed = ButtonBehavior(bb, id, &hovered, &held, ImGuiButtonFlags_None);
// Render
ImU32 bg_col = GetColorU32((held && hovered) ? ImGuiCol_ButtonActive : hovered ? ImGuiCol_ButtonHovered : ImGuiCol_Button);
ImU32 text_col = GetColorU32(ImGuiCol_Text);
if (hovered || held)
window->DrawList->AddCircleFilled(bb.GetCenter()/*+ ImVec2(0.0f, -0.5f)*/, g.FontSize * 0.5f + 1.0f, bg_col, 12);
RenderArrow(window->DrawList, bb.Min + g.Style.FramePadding, text_col, window->Collapsed ? ImGuiDir_Right : ImGuiDir_Down, 1.0f);
// Switch to moving the window after mouse is moved beyond the initial drag threshold
if (IsItemActive() && IsMouseDragging(0))
StartMouseMovingWindow(window);
return pressed;
}
ImGuiID ImGui::GetWindowScrollbarID(ImGuiWindow* window, ImGuiAxis axis)
{
return window->GetID(axis == ImGuiAxis_X ? "#SCROLLX" : "#SCROLLY");
}
// Return scrollbar rectangle, must only be called for corresponding axis if window->ScrollbarX/Y is set.
ImRect ImGui::GetWindowScrollbarRect(ImGuiWindow* window, ImGuiAxis axis)
{
const ImRect outer_rect = window->Rect();
const ImRect inner_rect = window->InnerRect;
const float border_size = window->WindowBorderSize;
const float scrollbar_size = window->ScrollbarSizes[axis ^ 1]; // (ScrollbarSizes.x = width of Y scrollbar; ScrollbarSizes.y = height of X scrollbar)
IM_ASSERT(scrollbar_size > 0.0f);
if (axis == ImGuiAxis_X)
return ImRect(inner_rect.Min.x, ImMax(outer_rect.Min.y, outer_rect.Max.y - border_size - scrollbar_size), inner_rect.Max.x, outer_rect.Max.y);
else
return ImRect(ImMax(outer_rect.Min.x, outer_rect.Max.x - border_size - scrollbar_size), inner_rect.Min.y, outer_rect.Max.x, inner_rect.Max.y);
}
void ImGui::Scrollbar(ImGuiAxis axis)
{
ImGuiContext& g = *GImGui;
ImGuiWindow* window = g.CurrentWindow;
const ImGuiID id = GetWindowScrollbarID(window, axis);
// Calculate scrollbar bounding box
ImRect bb = GetWindowScrollbarRect(window, axis);
ImDrawFlags rounding_corners = ImDrawFlags_RoundCornersNone;
if (axis == ImGuiAxis_X)
{
rounding_corners |= ImDrawFlags_RoundCornersBottomLeft;
if (!window->ScrollbarY)
rounding_corners |= ImDrawFlags_RoundCornersBottomRight;
}
else
{
if ((window->Flags & ImGuiWindowFlags_NoTitleBar) && !(window->Flags & ImGuiWindowFlags_MenuBar))
rounding_corners |= ImDrawFlags_RoundCornersTopRight;
if (!window->ScrollbarX)
rounding_corners |= ImDrawFlags_RoundCornersBottomRight;
}
float size_avail = window->InnerRect.Max[axis] - window->InnerRect.Min[axis];
float size_contents = window->ContentSize[axis] + window->WindowPadding[axis] * 2.0f;
ImS64 scroll = (ImS64)window->Scroll[axis];
ScrollbarEx(bb, id, axis, &scroll, (ImS64)size_avail, (ImS64)size_contents, rounding_corners);
window->Scroll[axis] = (float)scroll;
}
// Vertical/Horizontal scrollbar
// The entire piece of code below is rather confusing because:
// - We handle absolute seeking (when first clicking outside the grab) and relative manipulation (afterward or when clicking inside the grab)
// - We store values as normalized ratio and in a form that allows the window content to change while we are holding on a scrollbar
// - We handle both horizontal and vertical scrollbars, which makes the terminology not ideal.
// Still, the code should probably be made simpler..
bool ImGui::ScrollbarEx(const ImRect& bb_frame, ImGuiID id, ImGuiAxis axis, ImS64* p_scroll_v, ImS64 size_avail_v, ImS64 size_contents_v, ImDrawFlags flags)
{
ImGuiContext& g = *GImGui;
ImGuiWindow* window = g.CurrentWindow;
if (window->SkipItems)
return false;
const float bb_frame_width = bb_frame.GetWidth();
const float bb_frame_height = bb_frame.GetHeight();
if (bb_frame_width <= 0.0f || bb_frame_height <= 0.0f)
return false;
// When we are too small, start hiding and disabling the grab (this reduce visual noise on very small window and facilitate using the window resize grab)
float alpha = 1.0f;
if ((axis == ImGuiAxis_Y) && bb_frame_height < g.FontSize + g.Style.FramePadding.y * 2.0f)
alpha = ImSaturate((bb_frame_height - g.FontSize) / (g.Style.FramePadding.y * 2.0f));
if (alpha <= 0.0f)
return false;
const ImGuiStyle& style = g.Style;
const bool allow_interaction = (alpha >= 1.0f);
ImRect bb = bb_frame;
bb.Expand(ImVec2(-ImClamp(IM_FLOOR((bb_frame_width - 2.0f) * 0.5f), 0.0f, 3.0f), -ImClamp(IM_FLOOR((bb_frame_height - 2.0f) * 0.5f), 0.0f, 3.0f)));
// V denote the main, longer axis of the scrollbar (= height for a vertical scrollbar)
const float scrollbar_size_v = (axis == ImGuiAxis_X) ? bb.GetWidth() : bb.GetHeight();
// Calculate the height of our grabbable box. It generally represent the amount visible (vs the total scrollable amount)
// But we maintain a minimum size in pixel to allow for the user to still aim inside.
IM_ASSERT(ImMax(size_contents_v, size_avail_v) > 0.0f); // Adding this assert to check if the ImMax(XXX,1.0f) is still needed. PLEASE CONTACT ME if this triggers.
const ImS64 win_size_v = ImMax(ImMax(size_contents_v, size_avail_v), (ImS64)1);
const float grab_h_pixels = ImClamp(scrollbar_size_v * ((float)size_avail_v / (float)win_size_v), style.GrabMinSize, scrollbar_size_v);
const float grab_h_norm = grab_h_pixels / scrollbar_size_v;
// Handle input right away. None of the code of Begin() is relying on scrolling position before calling Scrollbar().
bool held = false;
bool hovered = false;
ItemAdd(bb_frame, id, NULL, ImGuiItemFlags_NoNav);
ButtonBehavior(bb, id, &hovered, &held, ImGuiButtonFlags_NoNavFocus);
const ImS64 scroll_max = ImMax((ImS64)1, size_contents_v - size_avail_v);
float scroll_ratio = ImSaturate((float)*p_scroll_v / (float)scroll_max);
float grab_v_norm = scroll_ratio * (scrollbar_size_v - grab_h_pixels) / scrollbar_size_v; // Grab position in normalized space
if (held && allow_interaction && grab_h_norm < 1.0f)
{
const float scrollbar_pos_v = bb.Min[axis];
const float mouse_pos_v = g.IO.MousePos[axis];
// Click position in scrollbar normalized space (0.0f->1.0f)
const float clicked_v_norm = ImSaturate((mouse_pos_v - scrollbar_pos_v) / scrollbar_size_v);
SetHoveredID(id);
bool seek_absolute = false;
if (g.ActiveIdIsJustActivated)
{
// On initial click calculate the distance between mouse and the center of the grab
seek_absolute = (clicked_v_norm < grab_v_norm || clicked_v_norm > grab_v_norm + grab_h_norm);
if (seek_absolute)
g.ScrollbarClickDeltaToGrabCenter = 0.0f;
else
g.ScrollbarClickDeltaToGrabCenter = clicked_v_norm - grab_v_norm - grab_h_norm * 0.5f;
}
// Apply scroll (p_scroll_v will generally point on one member of window->Scroll)
// It is ok to modify Scroll here because we are being called in Begin() after the calculation of ContentSize and before setting up our starting position
const float scroll_v_norm = ImSaturate((clicked_v_norm - g.ScrollbarClickDeltaToGrabCenter - grab_h_norm * 0.5f) / (1.0f - grab_h_norm));
*p_scroll_v = (ImS64)(scroll_v_norm * scroll_max);
// Update values for rendering
scroll_ratio = ImSaturate((float)*p_scroll_v / (float)scroll_max);
grab_v_norm = scroll_ratio * (scrollbar_size_v - grab_h_pixels) / scrollbar_size_v;
// Update distance to grab now that we have seeked and saturated
if (seek_absolute)
g.ScrollbarClickDeltaToGrabCenter = clicked_v_norm - grab_v_norm - grab_h_norm * 0.5f;
}
// Render
const ImU32 bg_col = GetColorU32(ImGuiCol_ScrollbarBg);