StyleDialog - A transparent dialog class with an optional custom frame

// Border.cpp: implementation of the Border class.
//
// Author:  Darren Sessions
//          
//
// Description:
//     Border Draws or Fills rounded rectangles for GDI+.  It was implemented
//	   to overcome the asymmetric issues associated with GDI+ round rectangles
//
// History
//     Version 1.0 - 2008 June 24
//     - Initial public release
//
// License:
//     This software is released under the Code Project Open License (CPOL),
//     which may be found here:  http://www.codeproject.com/info/eula.aspx
//     You are free to use this software in any way you like, except that you 
//     may not sell this source code.
//
//     This software is provided "as is" with no expressed or implied warranty.
//     I accept no liability for any damage or loss of business that this 
//     software may cause.
//
///////////////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "Border.h"

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

Border::Border()
{
}

Border::~Border()
{

}

//=============================================================================
//
// GetPath()
//
// Purpose:     Defines a the appropriate path and places it in the GraphicsPath
//
// Parameters:  pPath		- [out] pointer to GraphicsPath that will recieve the 
//									path data
//				r			- [in]	Rect that defines the round rectangle boundaries
//
// Returns:     None
//
void Border::GetPath(GraphicsPath *pPath, Rect r)
{	
	if(shape == RECTANGLE)
	{
		GetRectPath(pPath, r);
	}
	else
	{
		GetRoundRectPath(pPath, r);
	}
}


//=============================================================================
//
// GetRectPath()
//
// Purpose:     Defines a Rectangle and places it in the GraphicsPath
//
// Parameters:  pPath		- [out] pointer to GraphicsPath that will recieve the 
//									path data
//				r			- [in]	Rect that defines the round rectangle boundaries
//
// Returns:     None
//
void Border::GetRectPath(GraphicsPath *pPath, Rect r)
{
	pPath->Reset();
	pPath->AddRectangle(r);
	pPath->CloseFigure();
}

//=============================================================================
//
// GetRoundRectPath()
//
// Purpose:     Defines a Rounded Rectangle and places it in the GraphicsPath
//
// Parameters:  pPath		- [out] pointer to GraphicsPath that will recieve the 
//									path data
//				r			- [in]	Rect that defines the round rectangle boundaries
//
// Returns:     None
//
void Border::GetRoundRectPath(GraphicsPath *pPath, Rect r)
{
	// set the diameter
	int dia = 2*radius;

	// this isn't a round rect anymore but it 
	// can occur with progress bars
	if( (dia > r.Width) || (dia > r.Height) )
	{
		r.Inflate(0, -(dia/r.Width)); // add other case
		pPath->AddEllipse(r);
		return;
	}

	// define a corner 
	Rect Corner(r.X, r.Y, dia, dia);

	// begin path
	pPath->Reset();

	// top left
	pPath->AddArc(Corner, 180, 90);	

	// tweak needed for radius of 10 (dia of 20)
	if(dia == 20)
	{
		Corner.Width += 1; 
		Corner.Height += 1; 
		r.Width -=1; r.Height -= 1;
	}

	// top right
	Corner.X += (r.Width - dia - 1);
	pPath->AddArc(Corner, 270, 90);	
	
	// bottom right
	Corner.Y += (r.Height - dia - 1);
	pPath->AddArc(Corner,   0, 90);	
	
	// bottom left
	Corner.X -= (r.Width - dia - 1);
	pPath->AddArc(Corner,  90, 90);

	// end path
	pPath->CloseFigure();
}


//=============================================================================
//
// Draw()
//
// Purpose:     Draws a border with a solid pen
//
// Parameters:  pGraphics	- [in]	pointer to the Graphics device
//				r			- [in]	Rect that defines the round rectangle boundaries
//				ulclr		- [in]	Color value for the pen
//				brclr		- [in]  Bottom right pen color (SQUARE border only)
//				width		- [in]  width of the border
//		
// Returns:     None
//
void Border::Draw(Graphics* pGraphics, Rect r,  Color ulclr, Color brclr, int width)
{
	if(shape == RECTANGLE)
	{
		DrawRect(pGraphics, r, ulclr, brclr, width);
	}
	if(shape == ELLIPSE)
	{
		Pen pen(ulclr, 1);
		pen.SetAlignment(PenAlignmentCenter);
		RectF rf((float)r.X-1, (float)r.Y-1, (float)r.Width+1, (float)r.Height+1);
		pGraphics->DrawEllipse(&pen, rf);
	}
	else if(shape == TRANSITION)
	{
		// disable smoothing for the clip fill
		SmoothingMode oldMode = pGraphics->GetSmoothingMode();
		pGraphics->SetSmoothingMode(SmoothingModeNone);

		// fill the transition zone using a clip region
		pGraphics->SetClip(r, CombineModeReplace);

		// fill one pixel width into the round rect if width > 1
		// this supresses any transition antialiasing
		Rect cr(r); if(width > 1) cr.Inflate(-1, -1);

		// use local clip function for round rect
		SetBorderClip(pGraphics, cr, CombineModeExclude);

		// fill with the border color
		SolidBrush sbr(ulclr);
		pGraphics->FillRectangle(&sbr, r);

		// clear the clipping region
		pGraphics->ResetClip();

		// restore any smoothing mode
		pGraphics->SetSmoothingMode(oldMode);

		// now draw the round border
		DrawRoundRect(pGraphics, r, ulclr, width);
	
	}
	else
	{
		DrawRoundRect(pGraphics, r, ulclr, width);
	}
}

//=============================================================================
//
// DrawRect()
//
// Purpose:     Draws a rectangle with a solid pen
//
// Parameters:  pGraphics	- [in]	pointer to the Graphics device
//				r			- [in]	Rect that defines the round rectangle boundaries
//				color		- [in]	Color value for the brush
//				width		- [in]  width of the border
//		
// Returns:     None
//
void Border::DrawRect(Graphics* pGraphics, Rect r,  Color ulclr, Color brclr, int width)
{
	int i, left, top, bottom, right;

	// set to pixel mode
	Unit oldPageUnit = pGraphics->GetPageUnit();
	pGraphics->SetPageUnit(UnitPixel);

	// define the upper left pen
	Pen ulpen(ulclr, 1); ulpen.SetAlignment(PenAlignmentCenter);

	// define the bottom right pen
	Pen brpen(brclr, 1); brpen.SetAlignment(PenAlignmentCenter);

	// not sure why
	Rect rc(r); 

	for(i = 0; i < width; i++)
	{
		left = rc.X; top = rc.Y; bottom = rc.GetBottom()-1; right = rc.GetRight()-1;

		// left
		pGraphics->DrawLine(&ulpen, left, top, left, bottom);

		// top
		pGraphics->DrawLine(&ulpen, left, top, right, top);

		// right
		pGraphics->DrawLine(&brpen, right, top+1, right, bottom);

		// bottom
		pGraphics->DrawLine(&brpen, left+1, bottom, right, bottom);

		rc.Inflate(-1, -1);
	}

	// restore page unit
	pGraphics->SetPageUnit(oldPageUnit);

}

//=============================================================================
//
// DrawRoundRect()
//
// Purpose:     Draws a rounded rectangle with a solid pen
//
// Parameters:  pGraphics	- [in]	pointer to the Graphics device
//				r			- [in]	Rect that defines the round rectangle boundaries
//				color		- [in]	Color value for the brush
//				width		- [in]  width of the border
//		
// Returns:     None
//
void Border::DrawRoundRect(Graphics* pGraphics, Rect r,  Color color, int width)
{
	// set to pixel mode
	Unit oldPageUnit = pGraphics->GetPageUnit();
	pGraphics->SetPageUnit(UnitPixel);

	// define the pen
	Pen pen(color, 1);	
	pen.SetAlignment(PenAlignmentCenter);

	// get the corner path
	GraphicsPath path;

	// get path
	GetRoundRectPath(&path, r);

	// draw the round rect
	pGraphics->DrawPath(&pen, &path);	

	// save smoothing mode
	SmoothingMode oldMode = pGraphics->GetSmoothingMode(); 

	// if width > 1
	for(int i=1; i<width; i++)
	{
		// disable smoothing for brclr lines
		if(i == 1)				pGraphics->SetSmoothingMode(SmoothingModeNone);
		// re enable for last line
		if(i == (width - 1))	pGraphics->SetSmoothingMode(oldMode);

		// left stroke
		r.Inflate(-1, 0);

		// get the path
		GetRoundRectPath(&path, r);
		
		// draw the round rect
		pGraphics->DrawPath(&pen, &path);

		// up stroke
		r.Inflate(0, -1);

		// get the path
		GetRoundRectPath(&path, r);
		
		// draw the round rect
		pGraphics->DrawPath(&pen, &path);
	}

	// restore page unit
	pGraphics->SetPageUnit(oldPageUnit);
}

//=============================================================================
//
// FillRoundRect()
//
// Purpose:     Fills a rounded rectangle with a solid brush.  Draws the border
//				first then fills in the rectangle.
//
// Parameters:  pGraphics	- [in]	pointer to the Graphics device
//				r			- [in]	Rect that defines the round rectangle boundaries
//				color		- [in]	Color value for the brush
//				radius		- [in]  radius of the rounded corner
//		
// Returns:     None
//
void Border::FillRoundRect(Graphics* pGraphics, Rect r,  Color color, int radius)
{
	SolidBrush sbr(color);
	FillRoundRect(pGraphics, &sbr, r, color, radius);
}

//=============================================================================
//
// FillRoundRect()
//
// Purpose:     Fills a rounded rectangle with the passed brush.  Fills the 
//				rectangle then drawst the border.
//
// Parameters:  pGraphics	- [in]	pointer to the Graphics device
//				pBrush		- [in]  pointer to a Brush
//				r			- [in]	Rect that defines the round rectangle boundaries
//				color		- [in]	Color value for the border (needed in case the 
//									brush is a type other than solid)
//				radius		- [in]  radius of the rounded corner
//		
// Returns:     None
//
void Border::FillRoundRect(Graphics* pGraphics, Brush* pBrush, Rect r, Color border, int radius)
{
	int dia	= 2*radius;

	// set to pixel mode
	Unit oldPageUnit = pGraphics->GetPageUnit();
	pGraphics->SetPageUnit(UnitPixel);

	// define the pen
	Pen pen(border, 1);	
	pen.SetAlignment(PenAlignmentCenter);

	// get the corner path
	GraphicsPath path;

	// get path
	GetRoundRectPath(&path, r);

	// fill
	pGraphics->FillPath(pBrush, &path);

	// draw the border last so it will be on top in case the color is different
	pGraphics->DrawPath(&pen, &path);

	// restore page unit
	pGraphics->SetPageUnit(oldPageUnit);
}

//=============================================================================
//
// SetBorderClip()
//
// Purpose:     Sets the clipping region to the inside of and including this border.
//				The SetClip(path) of GDI+ has the same problem that a fill path does 
//				on a round rectangle, so use GDI's function instead
//
// Parameters:  pGraphics	- [in]	pointer to the Graphics device
//		
// Returns:     None
//
void Border::SetBorderClip(Graphics* pGraphics, Rect rc, CombineMode mode)
{
	CRgn frgn; int dia;
	
	dia = 2*radius;

	if(shape == UNDEFINED)
	{
		// the border needs a shape
		ASSERT(FALSE);
	}
	if(shape == RECTANGLE)
	{
		frgn.CreateRectRgn(rc.X, rc.Y, rc.GetRight()+1, rc.GetBottom()+1);
	}
	else if(shape == ELLIPSE)
	{
		frgn.CreateEllipticRgn(rc.X-1, rc.Y-1, rc.GetRight()+2, rc.GetBottom()+2);
	}
	// handle this special case - TODO: add for Height < dia
	else if(rc.Width < dia)
	{
		rc.Width++; rc.Height++;
		Rect lrc(rc); lrc.Width = 2*dia; 
		Rect rrc(rc); rrc.Width = 2*dia; rrc.X = rrc.X - (rrc.Width - rc.Width);
		CRgn lrgn, rrgn;
		lrgn.CreateRoundRectRgn(lrc.X, lrc.Y, lrc.GetRight()+1, lrc.GetBottom()+1, dia+1, dia+1);
		rrgn.CreateRoundRectRgn(rrc.X, rrc.Y, rrc.GetRight()+1, rrc.GetBottom()+1, dia+1, dia+1);
		frgn.CreateRectRgn(0,0,0,0);
		frgn.CombineRgn(&lrgn, &rrgn, RGN_AND);
	}
	else
	{
		frgn.CreateRoundRectRgn(rc.X, rc.Y, rc.GetRight()+1, rc.GetBottom()+1, dia+1, dia+1);
	}

	Region grgn(frgn);

	pGraphics->SetClip(&grgn, mode);

}