/* ==========================================================================
CDiagramLine
Author : Johan Rosengren, Abstrakt Mekanik AB
Date : 2004-03-30
Purpose : Encapsulates a line object. Other line objects can be
derived from this class.
Description : First of all, we do not want constraints to the line
size (as we can't move the end points freely if that
is the case), so one SetRect must be modified. Second,
we need a non-rectangular body area for hit testing, a
line in this case. Third, we need only a subset of the
selection markers. All this is implemented in this
class, to serve as a model or base class for other line
objects.
Usage : Use as a model for line objects.
========================================================================*/
#include "stdafx.h"
#include "DiagramLine.h"
#include "Tokenizer.h"
#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif
VOID CALLBACK HitTest( int X, int Y, LPARAM data )
/* ============================================================
Function : HitTest
Description : Checks if the coordinate in the hitParams
struct falls within +/- 1 of the x, y
coordinates of this point of the line.
Return : nothing
Parameters : int X - Current x coordinate
int Y - Current y coordinate
LPARAM data - Pointer to a hitParams
struct containing the x,y
coordinates to check. The
hit element will be set to
TRUE if the condition is
met.
Usage : LineDDA callback function. Called for each
point of the line
============================================================*/
{
hitParams* obj = ( hitParams* ) data;
if( obj->x >= X - 1 && obj->x <= X + 1 && obj->y >= Y - 1 && obj->y <= Y + 1 )
obj->hit = TRUE;
}
VOID CALLBACK HitTestRect( int X, int Y, LPARAM data )
/* ============================================================
Function : HitTestRect
Description : Checks if the x, y coordinates of the line
falls withing the hitParamsRect rectangle.
Return : nothing
Parameters : int X - Current x coordinate
int Y - Current y coordinate
LPARAM data - Pointer to a hitParamsRect
struct containing the rect
to check. The hit element
will be set to TRUE if the
condition is met.
Usage : LineDDA callback function. Called for each
point of the line.
============================================================*/
{
hitParamsRect* obj = ( hitParamsRect* ) data;
CPoint pt( X, Y );
if( obj->rect.PtInRect( pt ) )
obj->hit = TRUE;
}
/////////////////////////////////////////////////////////////////////////////
// CDiagramLine
//
CDiagramLine::CDiagramLine()
/* ============================================================
Function : CDiagramLine::CDiagramLine
Description : constructor
Return : void
Parameters : none
Usage :
============================================================*/
{
SetMinimumSize( CSize( -1, -1 ) );
SetType( _T( "line" ) );
}
CDiagramLine::~CDiagramLine()
/* ============================================================
Function : CDiagramLine::~CDiagramLine
Description : destructor
Return : void
Parameters : none
Usage :
============================================================*/
{
}
CDiagramEntity* CDiagramLine::Clone()
/* ============================================================
Function : CDiagramLine::Clone
Description : Clones this object and returns a new one.
Return : CDiagramEntity* - The resulting clone
Parameters : none
Usage :
============================================================*/
{
CDiagramLine* obj = new CDiagramLine;
obj->Copy( this );
return obj;
}
void CDiagramLine::SetRect( CRect rect )
/* ============================================================
Function : CDiagramLine::SetRect
Description : Sets the rect of the object.
Return : void
Parameters : CRect rect -
Usage : Overriden to avoid normalization.
============================================================*/
{
SetLeft( rect.left );
SetTop( rect.top );
SetRight( rect.right );
SetBottom( rect.bottom );
}
BOOL CDiagramLine::BodyInRect( CRect rect ) const
/* ============================================================
Function : CDiagramLine::BodyInRect
Description : Checks if some part of the body of this
object lies inside the rectangle rect.
Return : BOOL - TRUE if any part of the
object lies inside rect.
Parameters : CRect rect - The rect to test.
Usage : Shows one way to test a non-rectangular
object body - in this case a line.
============================================================*/
{
BOOL result = FALSE;
hitParamsRect hit;
hit.rect = rect;
hit.hit = FALSE;
LineDDA( ( int ) GetLeft(),
( int ) GetTop(),
( int ) GetRight(),
( int ) GetBottom(),
HitTestRect,
( LPARAM ) &hit );
if( hit.hit )
result = TRUE;
return result;
}
int CDiagramLine::GetHitCode( CPoint point ) const
/* ============================================================
Function : CDiagramLine::GetHitCode
Description : Returns the hit point constant (DEHT_,
defined in DiagramEntity.h) for point.
Return : int - The resulting hit point
constant, DEHT_NONE if
none.
Parameters : CPoint point - The point to test.
Usage : Shows one way to hit point test a non-
rectangular area.
============================================================*/
{
int result = DEHT_NONE;
CRect rect = GetRect();
hitParams hit;
hit.hit = FALSE;
hit.x = point.x;
hit.y = point.y;
LineDDA( ( int ) GetLeft(),
( int ) GetTop(),
( int ) GetRight(),
( int ) GetBottom(),
HitTest,
(LPARAM) &hit );
if( hit.hit )
result = DEHT_BODY;
CRect rectTest;
rectTest = GetSelectionMarkerRect( DEHT_TOPLEFT, rect );
if( rectTest.PtInRect( point ) )
result = DEHT_TOPLEFT;
rectTest = GetSelectionMarkerRect( DEHT_BOTTOMRIGHT, rect );
if( rectTest.PtInRect( point ) )
result = DEHT_BOTTOMRIGHT;
return result;
}
void CDiagramLine::Draw( CDC* dc, CRect rect )
/* ============================================================
Function : CDiagramLine::Draw
Description : Draws the object.
Return : void
Parameters : CDC* dc - CDC to draw to
CRect rect - True (zoomed) rectangle to
draw to.
Usage :
============================================================*/
{
dc->SelectStockObject( BLACK_PEN );
dc->MoveTo( rect.TopLeft() );
dc->LineTo( rect.BottomRight() );
}
HCURSOR CDiagramLine::GetCursor( int hit ) const
/* ============================================================
Function : CDiagramLine::GetCursor
Description : Returns the cursor for a specific hit
point.
Return : HCURSOR - The cursor to display, or NULL
if default.
Parameters : int hit - The hit point constant (DEHT_,
defined in DiagramEntity.h) to
show a cursor for.
Usage : Shows the cursor for a subset of the hit
points. Will also show cursors different
from the standard ones.
============================================================*/
{
HCURSOR cursor = NULL;
switch( hit )
{
case DEHT_BODY:
cursor = LoadCursor( NULL, IDC_SIZEALL );
break;
case DEHT_TOPLEFT:
cursor = LoadCursor( NULL, IDC_SIZEALL );
break;
case DEHT_BOTTOMRIGHT:
cursor = LoadCursor( NULL, IDC_SIZEALL );
break;
}
return cursor;
}
void CDiagramLine::DrawSelectionMarkers( CDC* dc, CRect rect ) const
/* ============================================================
Function : CDiagramLine::DrawSelectionMarkers
Description : Draws selection markers for this object.
Return : void
Parameters : CDC* dc - CDC to draw to.
CRect rect - True object rectangle.
Usage : Draws a subset of the standard selection
markers.
============================================================*/
{
// Draw selection markers
CRect rectSelect;
dc->SelectStockObject( BLACK_BRUSH );
rectSelect = GetSelectionMarkerRect( DEHT_TOPLEFT, rect );
dc->Rectangle( rectSelect );
rectSelect = GetSelectionMarkerRect( DEHT_BOTTOMRIGHT, rect );
dc->Rectangle( rectSelect );
}
CDiagramEntity* CDiagramLine::CreateFromString( const CString& str )
/* ============================================================
Function : CDiagramLine::CreateFromString
Description : Static factory function to create a
CDiagramLine object from str.
Return : CDiagramEntity* - Resulting object,
NULL if str is not
a representation of
a CDiagramLine.
Parameters : const CString& str - String representation
to decode.
Usage : One proposed mechanism for loading/creating
CDiagramEntity-derived objects from a text
stream.
============================================================*/
{
CDiagramLine* obj = new CDiagramLine;
if(!obj->FromString( str ) )
{
delete obj;
obj = NULL;
}
return obj;
}
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