// ImGui library
// See .cpp file for commentary.
// See ImGui::ShowTestWindow() for sample code.
// Read 'Programmer guide' in .cpp for notes on how to setup ImGui in your codebase.
// Get latest version at https://github.com/ocornut/imgui

#pragma once

struct ImDrawList;
struct ImBitmapFont;
struct ImGuiAabb;
struct ImGuiIO;
struct ImGuiStorage;
struct ImGuiStyle;
struct ImGuiWindow;

#include "imconfig.h"
#include <float.h>			// FLT_MAX
#include <stdarg.h>			// va_list
#include <stdlib.h>			// NULL

#ifndef IM_ASSERT
#include <assert.h>
#define IM_ASSERT(_EXPR)	assert(_EXPR)
#endif

typedef unsigned int ImU32;
typedef ImU32 ImGuiID;
typedef int ImGuiCol;				// enum ImGuiCol_
typedef int ImGuiKey;				// enum ImGuiKey_
typedef int ImGuiColorEditMode;		// enum ImGuiColorEditMode_
typedef int ImGuiWindowFlags;		// enum ImGuiWindowFlags_
typedef int ImGuiInputTextFlags;	// enum ImGuiInputTextFlags_
typedef ImBitmapFont* ImFont;

struct ImVec2
{
	float x, y;
	ImVec2() {}
	ImVec2(float _x, float _y) { x = _x; y = _y; }

#ifdef IM_VEC2_CLASS_EXTRA
	IM_VEC2_CLASS_EXTRA
#endif
};

struct ImVec4
{
	float x, y, z, w;
	ImVec4() {}
	ImVec4(float _x, float _y, float _z, float _w) { x = _x; y = _y; z = _z; w = _w; }

#ifdef IM_VEC4_CLASS_EXTRA
	IM_VEC4_CLASS_EXTRA
#endif
};

// std::vector<> like class to avoid dragging dependencies (also: windows implementation of STL with debug enabled is absurdly slow, so let's bypass it so our code runs fast in debug). 
// this implementation does NOT call c++ constructors! we don't need them! also only provide the minimum functionalities we need.
#ifndef ImVector
template<typename T>
class ImVector
{
private:
	size_t						Size;
	size_t						Capacity;
	T*							Data;

public:
	typedef T					value_type;
	typedef value_type*			iterator;
	typedef const value_type*	const_iterator;

	ImVector()					{ Size = Capacity = 0; Data = NULL; }
	~ImVector()					{ if (Data) free(Data); }

	inline bool					empty() const					{ return Size == 0; }
	inline size_t				size() const					{ return Size; }
	inline size_t				capacity() const				{ return Capacity; }

    inline value_type&			at(size_t i)					{ IM_ASSERT(i < Size); return Data[i]; }
    inline const value_type&	at(size_t i) const				{ IM_ASSERT(i < Size); return Data[i]; }
    inline value_type&			operator[](size_t i)			{ IM_ASSERT(i < Size); return Data[i]; }
    inline const value_type&	operator[](size_t i) const		{ IM_ASSERT(i < Size); return Data[i]; }

	inline void					clear()							{ if (Data) { Size = Capacity = 0; free(Data); Data = NULL; } }
	inline iterator				begin()							{ return Data; }
	inline const_iterator		begin() const					{ return Data; }
	inline iterator				end()							{ return Data + Size; }
	inline const_iterator		end() const						{ return Data + Size; }
	inline value_type&			front()							{ return at(0); }
	inline const value_type&	front() const					{ return at(0); }
	inline value_type&			back()							{ IM_ASSERT(Size > 0); return at(Size-1); }
	inline const value_type&	back() const					{ IM_ASSERT(Size > 0); return at(Size-1); }
	inline void					swap(ImVector<T>& rhs)			{ const size_t rhs_size = rhs.Size; rhs.Size = Size; Size = rhs_size; const size_t rhs_cap = rhs.Capacity; rhs.Capacity = Capacity; Capacity = rhs_cap; value_type* rhs_data = rhs.Data; rhs.Data = Data; Data = rhs_data; }

	inline void					reserve(size_t new_capacity)	{ Data = (value_type*)realloc(Data, new_capacity * sizeof(value_type)); Capacity = new_capacity; }
	inline void					resize(size_t new_size)			{ if (new_size > Capacity) reserve(new_size); Size = new_size; }

	inline void					push_back(const value_type& v)	{ if (Size == Capacity) reserve(Capacity ? Capacity * 2 : 4); Data[Size++] = v; }
	inline void					pop_back()						{ IM_ASSERT(Size > 0); Size--; }

	inline iterator				erase(const_iterator it)		{ IM_ASSERT(it >= begin() && it < end()); const int off = it - begin(); memmove(Data + off, Data + off + 1, (Size - off - 1) * sizeof(value_type)); Size--; return Data + off; }
	inline void					insert(const_iterator it, const value_type& v)	{ IM_ASSERT(it >= begin() && it <= end()); const int off = it - begin(); if (Size == Capacity) reserve(Capacity ? Capacity * 2 : 4); if (off < (int)Size) memmove(Data + off + 1, Data + off, (Size - off) * sizeof(value_type)); Data[off] = v; Size++; }
};
#endif // #ifndef ImVector

// Helpers at bottom of the file:
// - if (IMGUI_ONCE_UPON_A_FRAME)		// Execute a block of code once per frame only
// - struct ImGuiTextFilter				// Parse and apply text filter. In format "aaaaa[,bbbb][,ccccc]"
// - struct ImGuiTextBuffer				// Text buffer for logging/accumulating text
// - struct ImGuiStorage				// Custom key value storage (if you need to alter open/close states manually)
// - struct ImDrawList					// Draw command list
// - struct ImBitmapFont				// Bitmap font loader

// ImGui End-user API
// In a namespace so that user can add extra functions (e.g. Value() helpers for your vector or common types)
namespace ImGui
{
	// Main
	ImGuiIO&	GetIO();
	ImGuiStyle&	GetStyle();
	void		NewFrame();
	void		Render();
	void		Shutdown();
	void		ShowUserGuide();
	void		ShowStyleEditor(ImGuiStyle* ref = NULL);
	void		ShowTestWindow(bool* open = NULL);

	// Window
	bool		Begin(const char* name = "Debug", bool* open = NULL, ImVec2 size = ImVec2(0,0), float fill_alpha = -1.0f, ImGuiWindowFlags flags = 0);
	void		End();
	void		BeginChild(const char* str_id, ImVec2 size = ImVec2(0,0), bool border = false, ImGuiWindowFlags extra_flags = 0);
	void		EndChild();
	bool		GetWindowIsFocused();
	float		GetWindowWidth();
	ImVec2		GetWindowPos();														// you should rarely need/care about the window position, but it can be useful if you want to use your own drawing
	void		SetWindowPos(const ImVec2& pos);									// set current window pos
	ImVec2		GetWindowSize();
	ImVec2		GetWindowContentRegionMin();
	ImVec2		GetWindowContentRegionMax();
	ImDrawList*	GetWindowDrawList();
	void		SetFontScale(float scale);
	void		SetScrollPosHere();
	void		SetTreeStateStorage(ImGuiStorage* tree);
	ImGuiStorage* GetTreeStateStorage();
	void		PushItemWidth(float item_width);
	void		PopItemWidth();
	float		GetItemWidth();
	void		PushAllowKeyboardFocus(bool v);
	void		PopAllowKeyboardFocus();
	void		PushStyleColor(ImGuiCol idx, const ImVec4& col);
	void		PopStyleColor();

	// Tooltip
	void		SetTooltip(const char* fmt, ...);									// set tooltip under mouse-cursor, typically use with ImGui::IsHovered(). last call wins.
	void		BeginTooltip();														// use to create full-featured tooltip windows that aren't just text. 
	void		EndTooltip();

	// Layout
	void		Separator();														// horizontal line
	void		SameLine(int column_x = 0, int spacing_w = -1);						// call between widgets to layout them horizontally
	void		Spacing();
	void		Columns(int count = 1, const char* id = NULL, bool border=true);	// setup number of columns
	void		NextColumn();														// next column
	float		GetColumnOffset(int column_index = -1);
	void		SetColumnOffset(int column_index, float offset);
	float		GetColumnWidth(int column_index = -1);
	ImVec2		GetCursorPos();														// cursor position is relative to window position
	void		SetCursorPos(const ImVec2& pos);									// "
	void		AlignFirstTextHeightToWidgets();									// call once if the first item on the line is a Text() item and you want to vertically lower it to match higher widgets.
	float		GetTextLineSpacing();
	float		GetTextLineHeight();

	// ID scopes
	void		PushID(const char* str_id);
	void		PushID(const void* ptr_id);
	void		PushID(const int int_id);
	void		PopID();

	// Widgets
	void		Text(const char* fmt, ...);
	void		TextV(const char* fmt, va_list args);
	void		TextColored(const ImVec4& col, const char* fmt, ...);				// shortcut to doing PushStyleColor(ImGuiCol_Text, col); Text(fmt, ...); PopStyleColor();
	void		TextUnformatted(const char* text, const char* text_end = NULL);		// doesn't require null terminated string if 'text_end' is specified. no copy done to any bounded stack buffer, better for long chunks of text.
	void		LabelText(const char* label, const char* fmt, ...);
	void		BulletText(const char* fmt, ...);
	bool		Button(const char* label, ImVec2 size = ImVec2(0,0), bool repeat_when_held = false);
	bool		SmallButton(const char* label);
	bool		CollapsingHeader(const char* label, const char* str_id = NULL, const bool display_frame = true, const bool default_open = false);
	bool		SliderFloat(const char* label, float* v, float v_min, float v_max, const char* display_format = "%.3f", float power = 1.0f);
	bool		SliderFloat2(const char* label, float v[2], float v_min, float v_max, const char* display_format = "%.3f", float power = 1.0f);
	bool		SliderFloat3(const char* label, float v[3], float v_min, float v_max, const char* display_format = "%.3f", float power = 1.0f);
	bool		SliderFloat4(const char* label, float v[3], float v_min, float v_max, const char* display_format = "%.3f", float power = 1.0f);
	bool		SliderAngle(const char* label, float* v, float v_degrees_min = -360.0f, float v_degrees_max = +360.0f);		// *v in radians
	bool		SliderInt(const char* label, int* v, int v_min, int v_max, const char* display_format = "%.0f");
	void		PlotLines(const char* label, const float* values, int values_count, int values_offset = 0, const char* overlay_text = NULL, float scale_min = FLT_MAX, float scale_max = FLT_MAX, ImVec2 graph_size = ImVec2(0,0), size_t stride = sizeof(float));
	void		PlotHistogram(const char* label, const float* values, int values_count, int values_offset = 0, const char* overlay_text = NULL, float scale_min = FLT_MAX, float scale_max = FLT_MAX, ImVec2 graph_size = ImVec2(0,0), size_t stride = sizeof(float));
	void		Checkbox(const char* label, bool* v);
	void		CheckboxFlags(const char* label, unsigned int* flags, unsigned int flags_value);
	bool		RadioButton(const char* label, bool active);
	bool		RadioButton(const char* label, int* v, int v_button);
	bool		InputFloat(const char* label, float* v, float step = 0.0f, float step_fast = 0.0f, int decimal_precision = -1);
	bool		InputFloat2(const char* label, float v[2], int decimal_precision = -1);
	bool		InputFloat3(const char* label, float v[3], int decimal_precision = -1);
	bool		InputFloat4(const char* label, float v[4], int decimal_precision = -1);
	bool		InputInt(const char* label, int* v, int step = 1, int step_fast = 100);
	bool		InputText(const char* label, char* buf, size_t buf_size, ImGuiInputTextFlags flags = 0);
	bool		Combo(const char* label, int* current_item, const char** items, int items_count, int popup_height_items = 7);
	bool		Combo(const char* label, int* current_item, const char* items_separated_by_zeros, int popup_height_items = 7);		// Separate items with \0, end item-list with \0\0
	bool		Combo(const char* label, int* current_item, bool (*items_getter)(void* data, int idx, const char** out_text), void* data, int items_count, int popup_height_items = 7);
	bool		ColorButton(const ImVec4& col, bool small_height = false, bool outline_border = true);
	bool		ColorEdit3(const char* label, float col[3]);
	bool		ColorEdit4(const char* label, float col[4], bool show_alpha = true);
	void		ColorEditMode(ImGuiColorEditMode mode);
	bool		TreeNode(const char* str_label_id);									// if returning 'true' the user is responsible for calling TreePop
	bool		TreeNode(const char* str_id, const char* fmt, ...);					// "
	bool		TreeNode(const void* ptr_id, const char* fmt, ...);					// "
	void		TreePush(const char* str_id = NULL);								// already called by TreeNode(), but you can call Push/Pop yourself for layout purpose
	void		TreePush(const void* ptr_id = NULL);								// "
	void		TreePop();
	void		OpenNextNode(bool open);											// force open/close the next TreeNode or CollapsingHeader

	// Value helper output "name: value"
	// Freely declare your own in the ImGui namespace.
	void		Value(const char* prefix, bool b);
	void		Value(const char* prefix, int v);
	void		Value(const char* prefix, unsigned int v);
	void		Value(const char* prefix, float v, const char* float_format = NULL);
	void		Color(const char* prefix, const ImVec4& v);
	void		Color(const char* prefix, unsigned int v);

	// Logging
	void		LogButtons();
	void		LogToTTY(int max_depth = -1);
	void		LogToFile(int max_depth = -1, const char* filename = NULL);
	void		LogToClipboard(int max_depth = -1);

	// Utilities
	void		SetNewWindowDefaultPos(const ImVec2& pos);							// set position of window that do
	bool		IsHovered();														// was the last item active area hovered by mouse?
	ImVec2		GetItemBoxMin();													// get bounding box of last item
	ImVec2		GetItemBoxMax();													// get bounding box of last item
	bool		IsClipped(const ImVec2& item_size);									// to perform coarse clipping on user's side (as an optimisation)
	bool		IsKeyPressed(int key_index, bool repeat = true);					// key_index into the keys_down[512] array, imgui doesn't know the semantic of each entry
	bool		IsMouseClicked(int button, bool repeat = false);
	bool		IsMouseDoubleClicked(int button);
	bool		IsMouseHoveringBox(const ImVec2& box_min, const ImVec2& box_max);
	ImVec2		GetMousePos();
	float		GetTime();
	int			GetFrameCount();
	const char*	GetStyleColorName(ImGuiCol idx);
	void		GetDefaultFontData(const void** fnt_data, unsigned int* fnt_size, const void** png_data, unsigned int* png_size);

}; // namespace ImGui

// Flags for ImGui::Begin()
enum ImGuiWindowFlags_
{
	// Default: 0
	ImGuiWindowFlags_ShowBorders			= 1 << 0,
	ImGuiWindowFlags_NoTitleBar				= 1 << 1,
	ImGuiWindowFlags_NoResize				= 1 << 2,
	ImGuiWindowFlags_NoMove					= 1 << 3,
	ImGuiWindowFlags_NoScrollbar			= 1 << 4,
	ImGuiWindowFlags_ChildWindow			= 1 << 5,	// For internal use by BeginChild()
	ImGuiWindowFlags_ChildWindowAutoFitX	= 1 << 6,	// For internal use by BeginChild()
	ImGuiWindowFlags_ChildWindowAutoFitY	= 1 << 7,	// For internal use by BeginChild()
	ImGuiWindowFlags_ComboBox				= 1 << 8,	// For internal use by ComboBox()
	ImGuiWindowFlags_Tooltip				= 1 << 9,	// For internal use by Render() when using Tooltip
};

// Flags for ImGui::InputText()
enum ImGuiInputTextFlags_
{
	// Default: 0
	ImGuiInputTextFlags_CharsDecimal		= 1 << 0,
	ImGuiInputTextFlags_CharsHexadecimal	= 1 << 1,
	ImGuiInputTextFlags_AutoSelectAll		= 1 << 2,
	ImGuiInputTextFlags_AlignCenter			= 1 << 3,
};

// User fill ImGuiIO.KeyMap[] array with indices into the ImGuiIO.KeysDown[512] array
enum ImGuiKey_
{
	ImGuiKey_Tab,
	ImGuiKey_LeftArrow,
	ImGuiKey_RightArrow,
	ImGuiKey_UpArrow,
	ImGuiKey_DownArrow,
	ImGuiKey_Home,
	ImGuiKey_End,
	ImGuiKey_Delete,
	ImGuiKey_Backspace,
	ImGuiKey_Enter,
	ImGuiKey_Escape,
	ImGuiKey_A,			// for CTRL+A: select all
	ImGuiKey_C,			// for CTRL+C: copy
	ImGuiKey_V,			// for CTRL+V: paste
	ImGuiKey_X,			// for CTRL+X: cut
	ImGuiKey_Y,			// for CTRL+Y: redo
	ImGuiKey_Z,			// for CTRL+Z: undo
	ImGuiKey_COUNT,
};

enum ImGuiCol_
{
	ImGuiCol_Text,
	ImGuiCol_WindowBg,
	ImGuiCol_Border,
	ImGuiCol_BorderShadow,
	ImGuiCol_FrameBg,				// Background of checkbox, radio button, plot, slider, text input
	ImGuiCol_TitleBg,
	ImGuiCol_TitleBgCollapsed,
	ImGuiCol_ScrollbarBg,
	ImGuiCol_ScrollbarGrab,
	ImGuiCol_ScrollbarGrabHovered,
	ImGuiCol_ScrollbarGrabActive,
	ImGuiCol_ComboBg,
	ImGuiCol_CheckHovered,
	ImGuiCol_CheckActive,
	ImGuiCol_SliderGrab,
	ImGuiCol_SliderGrabActive,
	ImGuiCol_Button,
	ImGuiCol_ButtonHovered,
	ImGuiCol_ButtonActive,
	ImGuiCol_Header,
	ImGuiCol_HeaderHovered,
	ImGuiCol_HeaderActive,
	ImGuiCol_Column,
	ImGuiCol_ColumnHovered,
	ImGuiCol_ColumnActive,
	ImGuiCol_ResizeGrip,
	ImGuiCol_ResizeGripHovered,
	ImGuiCol_ResizeGripActive,
	ImGuiCol_CloseButton,
	ImGuiCol_CloseButtonHovered,
	ImGuiCol_CloseButtonActive,
	ImGuiCol_PlotLines,
	ImGuiCol_PlotLinesHovered,
	ImGuiCol_PlotHistogram,
	ImGuiCol_PlotHistogramHovered,
	ImGuiCol_TextSelectedBg,
	ImGuiCol_TooltipBg,
	ImGuiCol_COUNT,
};

enum ImGuiColorEditMode_
{
	ImGuiColorEditMode_UserSelect = -1,
	ImGuiColorEditMode_RGB = 0,
	ImGuiColorEditMode_HSV = 1,
	ImGuiColorEditMode_HEX = 2,
};

struct ImGuiStyle
{
	float		Alpha;						// Global alpha applies to everything in ImGui
	ImVec2		WindowPadding;				// Padding within a window
	ImVec2		WindowMinSize;				// Minimum window size
	ImVec2		FramePadding;				// Padding within a framed rectangle (used by most widgets)
	ImVec2		ItemSpacing;				// Horizontal and vertical spacing between widgets/lines
	ImVec2		ItemInnerSpacing;			// Horizontal and vertical spacing between within elements of a composed widget (e.g. a slider and its label)
	ImVec2		TouchExtraPadding;			// Expand bounding box for touch-based system where touch position is not accurate enough (unnecessary for mouse inputs). Unfortunately we don't sort widgets so priority on overlap will always be given to the first widget running. So dont grow this too much!
	ImVec2		AutoFitPadding;				// Extra space after auto-fit (double-clicking on resize grip)
	float		WindowFillAlphaDefault;		// Default alpha of window background, if not specified in ImGui::Begin()
	float		WindowRounding;				// Radius of window corners rounding. Set to 0.0f to have rectangular windows
	float		TreeNodeSpacing;			// Horizontal spacing when entering a tree node
	float		ColumnsMinSpacing;			// Minimum horizontal spacing between two columns
	float		ScrollBarWidth;				// Width of the vertical scroll bar
	ImVec4		Colors[ImGuiCol_COUNT];

	ImGuiStyle();
};

// This is where your app communicate with ImGui. Call ImGui::GetIO() to access.
// Read 'Programmer guide' section in .cpp file for general usage.
struct ImGuiIO
{
	// Settings (fill once)					// Default value:
	ImVec2		DisplaySize;				// <unset>					// Display size, in pixels. For clamping windows positions.
	float		DeltaTime;					// = 1.0f/60.0f				// Time elapsed since last frame, in seconds.
	float		IniSavingRate;				// = 5.0f					// Maximum time between saving .ini file, in seconds. Set to a negative value to disable .ini saving.
	const char* IniFilename;				// = "imgui.ini"			// Absolute path to .ini file.
	const char*	LogFilename;				// = "imgui_log.txt"		// Absolute path to .log file.
	float		MouseDoubleClickTime;		// = 0.30f					// Time for a double-click, in seconds.
	float		MouseDoubleClickMaxDist;	// = 6.0f					// Distance threshold to stay in to validate a double-click, in pixels.
	int			KeyMap[ImGuiKey_COUNT];		// <unset>					// Map of indices into the KeysDown[512] entries array
	ImFont		Font;						// <auto>					// Gets passed to text functions. Typedef ImFont to the type you want (ImBitmapFont* or your own font).
	float		FontHeight;					// <auto>					// Default font height, must be the vertical distance between two lines of text, aka == CalcTextSize(" ").y
	bool		FontAllowScaling;			// = false					// Set to allow scaling text with CTRL+Wheel.
	float		PixelCenterOffset;			// = 0.5f					// Set to 0.0f for DirectX <= 9, 0.5f for Direct3D >= 10 and OpenGL.

	// Settings - Rendering function (REQUIRED)
	// See example code if you are unsure of how to implement this.
	void		(*RenderDrawListsFn)(ImDrawList** const draw_lists, int count);

	// Settings - Clipboard Support
	// Override to provide your clipboard handlers.
	// On Windows architecture, defaults to use the native Win32 clipboard, otherwise default to use a ImGui private clipboard. 
	// NB- for SetClipboardTextFn, the string is *NOT* zero-terminated at 'text_end'
	const char*	(*GetClipboardTextFn)();										
	void		(*SetClipboardTextFn)(const char* text, const char* text_end);

	// Input - Fill before calling NewFrame()
	ImVec2		MousePos;					// Mouse position, in pixels (set to -1,-1 if no mouse / on another screen, etc.)
	bool		MouseDown[5];				// Mouse buttons. ImGui itself only uses button 0 (left button) but you can use others as storage for convenience.
	int			MouseWheel;					// Mouse wheel: -1,0,+1
	bool		KeyCtrl;					// Keyboard modifier pressed: Control
	bool		KeyShift;					// Keyboard modifier pressed: Shift
	bool		KeysDown[512];				// Keyboard keys that are pressed (in whatever order user naturally has access to keyboard data)
	char		InputCharacters[16];		// List of characters input (translated by user from keypress+keyboard state). Fill using AddInputCharacter() helper.

	// Output - Retrieve after calling NewFrame(), you can use them to discard inputs or hide them from the rest of your application
	bool		WantCaptureMouse;			// ImGui is using your mouse input (= window is being hovered or widget is active).
	bool		WantCaptureKeyboard;		// imGui is using your keyboard input (= widget is active).

	// Function
	void		AddInputCharacter(char c);	// Helper to add a new character into InputCharacters[]

	// [Internal] ImGui will maintain those fields for you
	ImVec2		MousePosPrev;
	ImVec2		MouseDelta;
	bool		MouseClicked[5];
	ImVec2		MouseClickedPos[5];
	float		MouseClickedTime[5];
	bool		MouseDoubleClicked[5];
	float		MouseDownTime[5];
	float		KeysDownTime[512];

	ImGuiIO();
};

//-----------------------------------------------------------------------------
// Helpers
//-----------------------------------------------------------------------------

// Helper: execute a block of code once a frame only
// Usage: if (IMGUI_ONCE_UPON_A_FRAME) {/*do something once a frame*/)
#define IMGUI_ONCE_UPON_A_FRAME			static ImGuiOncePerFrame im = ImGuiOncePerFrame()
struct ImGuiOncePerFrame
{
	ImGuiOncePerFrame() : LastFrame(-1) {}
	operator bool() const { return TryIsNewFrame(); }
private:
	mutable int LastFrame;
	bool		TryIsNewFrame() const	{ const int current_frame = ImGui::GetFrameCount(); if (LastFrame == current_frame) return false; LastFrame = current_frame; return true; }
};

// Helper: Parse and apply text filter. In format "aaaaa[,bbbb][,ccccc]"
struct ImGuiTextFilter
{
	struct TextRange 
	{ 
		const char* b; 
		const char* e;

		TextRange() { b = e = NULL; }
		TextRange(const char* _b, const char* _e) { b = _b; e = _e; }
		const char* begin() const { return b; }
		const char* end() const { return e; }
		bool empty() const { return b == e; }
		char front() const { return *b; }
		static bool isblank(char c) { return c == ' ' && c == '\t'; } 
		void trim_blanks() { while (b < e && isblank(*b)) b++; while (e > b && isblank(*(e-1))) e--; }
		void split(char separator, ImVector<TextRange>& out);
	};

	char				InputBuf[256];
	ImVector<TextRange>	Filters;
	int					CountGrep;

	ImGuiTextFilter();
	void Clear() { InputBuf[0] = 0; Build(); }
	void Draw(const char* label = "Filter (inc,-exc)", float width = -1.0f);	// Helper calling InputText+Build
	bool PassFilter(const char* val) const;
	bool IsActive() const { return !Filters.empty(); }
	void Build();
};

// Helper: Text buffer for logging/accumulating text
struct ImGuiTextBuffer
{
	ImVector<char>		Buf;

	ImGuiTextBuffer()	{ Buf.push_back(0); }
	const char*			begin() const { return Buf.begin(); }
	const char*			end() const { return Buf.end()-1; }
	size_t				size() const { return Buf.size()-1; }
	bool				empty() { return Buf.empty(); }
	void				clear() { Buf.clear(); Buf.push_back(0); }
	void				append(const char* fmt, ...);
};

// Helper: Key->value storage
// - Store collapse state for a tree
// - Store color edit options, etc.
// Typically you don't have to worry about this since a storage is held within each Window.
// Declare your own storage if you want to manipulate the open/close state of a particular sub-tree in your interface.
struct ImGuiStorage
{
	struct Pair { ImU32 key; int val; };
	ImVector<Pair>	Data;

	void	Clear();
	int		GetInt(ImU32 key, int default_val = 0);
	void	SetInt(ImU32 key, int val);
	void	SetAllInt(int val);

	int*	Find(ImU32 key);
	void	Insert(ImU32 key, int val);
};

//-----------------------------------------------------------------------------
// Draw List
// Hold a series of drawing commands. The user provide a renderer for ImDrawList
//-----------------------------------------------------------------------------

struct ImDrawCmd
{
	unsigned int	vtx_count;
	ImVec4			clip_rect;
};

#ifndef IMGUI_FONT_TEX_UV_FOR_WHITE
#define IMGUI_FONT_TEX_UV_FOR_WHITE	ImVec2(0.f,0.f)
#endif

// sizeof() == 20
struct ImDrawVert
{
	ImVec2	pos;
	ImVec2  uv;
	ImU32	col;
};

// Draw command list
// User is responsible for providing a renderer for this in ImGuiIO::RenderDrawListFn
struct ImDrawList
{
	// This is what you have to render
	ImVector<ImDrawCmd>		commands;			// commands
	ImVector<ImDrawVert>	vtx_buffer;			// each command consume ImDrawCmd::vtx_count of those

	// [Internal to ImGui]
	ImVector<ImVec4>		clip_rect_stack;	// [internal] clip rect stack while building the command-list (so text command can perform clipping early on)
	ImDrawVert*				vtx_write;			// [internal] point within vtx_buffer after each add command (to avoid using the ImVector<> operators too much)

	ImDrawList() { Clear(); }

	void Clear();
	void PushClipRect(const ImVec4& clip_rect);
	void PopClipRect();
	void ReserveVertices(unsigned int vtx_count);
	void AddVtx(const ImVec2& pos, ImU32 col);
	void AddVtxLine(const ImVec2& a, const ImVec2& b, ImU32 col);

	// Primitives
	void AddLine(const ImVec2& a, const ImVec2& b, ImU32 col);
	void AddRect(const ImVec2& a, const ImVec2& b, ImU32 col, float rounding = 0.0f, int rounding_corners=0x0F);
	void AddRectFilled(const ImVec2& a, const ImVec2& b, ImU32 col, float rounding = 0.0f, int rounding_corners=0x0F);
	void AddTriangleFilled(const ImVec2& a, const ImVec2& b, const ImVec2& c, ImU32 col);
	void AddCircle(const ImVec2& centre, float radius, ImU32 col, int num_segments = 12);
	void AddCircleFilled(const ImVec2& centre, float radius, ImU32 col, int num_segments = 12);
	void AddArc(const ImVec2& center, float rad, ImU32 col, int a_min, int a_max, bool tris=false, const ImVec2& third_point_offset = ImVec2(0,0));
	void AddText(ImFont font, float font_size, const ImVec2& pos, ImU32 col, const char* text_begin, const char* text_end);
};

// Optional bitmap font data loader & renderer into vertices
//	#define ImFont to ImBitmapFont to use
// Using the .fnt format exported by BMFont
//  - tool: http://www.angelcode.com/products/bmfont
//  - file-format: http://www.angelcode.com/products/bmfont/doc/file_format.html
// Assume valid file data (won't handle invalid/malicious data)
// Handle a subset of parameters.
//  - kerning pair are not supported (because ImGui code does per-character CalcTextSize calls, need to turn it into something more stateful to allow kerning)
struct ImBitmapFont
{
#pragma pack(push, 1)
	struct FntInfo
	{
		signed short	FontSize;
		unsigned char	BitField;		// bit 0: smooth, bit 1: unicode, bit 2: italic, bit 3: bold, bit 4: fixedHeight, bits 5-7: reserved
		unsigned char	CharSet;
		unsigned short	StretchH;
		unsigned char	AA;
		unsigned char	PaddingUp, PaddingRight, PaddingDown, PaddingLeft;
		unsigned char	SpacingHoriz, SpacingVert;
		unsigned char	Outline;
		//char			FontName[];
	};

	struct FntCommon
	{
		unsigned short	LineHeight;
		unsigned short	Base;
		unsigned short	ScaleW, ScaleH;
		unsigned short	Pages;
		unsigned char	BitField;
		unsigned char	Channels[4];
	};

	struct FntGlyph
	{
		unsigned int	Id;
		unsigned short	X, Y;
		unsigned short	Width, Height;
		signed short	XOffset, YOffset;
		signed short	XAdvance;
		unsigned char	Page;
		unsigned char	Channel;
	};

	struct FntKerning
	{
		unsigned int	IdFirst;
		unsigned int	IdSecond;
		signed short	Amount;
	};
#pragma pack(pop)

	unsigned char*			Data;				// Raw data, content of .fnt file
	int						DataSize;			//
	bool					DataOwned;			// 
	const FntInfo*			Info;				// (point into raw data)
	const FntCommon*		Common;				// (point into raw data)
	const FntGlyph*			Glyphs;				// (point into raw data)
	size_t					GlyphsCount;		//
	const FntKerning*		Kerning;			// (point into raw data)
	size_t					KerningCount;		//
	int						TabCount;			// FIXME: mishandled (add fixed amount instead of aligning to column)
	ImVector<const char*>	Filenames;			// (point into raw data)
	ImVector<int>			IndexLookup;		// (built)

	ImBitmapFont();
	~ImBitmapFont() { Clear(); }

	bool					LoadFromMemory(const void* data, int data_size);
	bool					LoadFromFile(const char* filename);
	void					Clear();
	void					BuildLookupTable();
	const FntGlyph *		FindGlyph(unsigned short c) const;
	float					GetFontSize() const	{ return (float)Info->FontSize; }

	ImVec2					CalcTextSize(float size, float max_width, const char* text_begin, const char* text_end, const char** remaining = NULL) const;
	void					RenderText(float size, ImVec2 pos, ImU32 col, const ImVec4& clip_rect, const char* text_begin, const char* text_end, ImDrawVert*& out_vertices) const;
};