OpZoom Class Reference

This operation can perform zooms in and out of the current DocView, either by an immediate call to the ZoomIn/ZoomOut/ZoomInOnRect/ZoomAtPoint functions, or by a call to the DoDrag function, which starts a mouse drag to define a zoom box. More...

#include <zoomops.h>

Inheritance diagram for OpZoom:

List of all members.

Public Member Functions
	OpZoom ()
	Default constructor. To run a zoom drag, call the DoDrag() function.
virtual void	Do (OpDescriptor *)
	Performs the zoom operation.
BOOL	DoDrag (Spread *pStartSpread, const DocCoord &dcStartPos, ClickModifiers cmods)
	Starts an auto-scroll drag operation at the given mouse position. Note that this function hides the base-class DoDrag() function.
virtual BOOL	SnappingDrag ()
void	ZoomOut (const WorkCoord &wcZoom, BOOL fEndOp=TRUE)
	Zooms out of the current DocView by one step. By default this function will call the End() function for this operation afterwards.
void	ZoomOut (Spread *pZoomSpread, const DocCoord &dcZoomPos, BOOL fEndOp=TRUE)
	Zooms out of the current DocView by one step. By default this function will call the End() function for this operation afterwards.
void	ZoomIn (const WorkCoord &wcZoom, BOOL fEndOp=TRUE)
	Zooms into the current DocView by one step. By default this function will call the End() function for this operation afterwards.
void	ZoomIn (Spread *pZoomSpread, const DocCoord &dcZoomPos, BOOL fEndOp=TRUE)
	Zooms in on the current DocView by one step. By default this function will call the End() function for this operation afterwards.
void	ZoomTo (const WorkCoord &wcZoom, INT32 Percent, BOOL fEndOp=TRUE)
	Zooms into the current DocView by one step. By default this function will call the End() function for this operation afterwards.
void	ZoomInOnRect (const WorkRect &wrZoom, BOOL fEndOp=TRUE)
	Zooms so that the given work rectangle completely fills the current DocView view extents. By default this function will call the End() function for this operation afterwards.
void	ZoomInOnRect (Spread *pZoomSpread, const DocRect &dcZoomRect, BOOL fEndOp=TRUE)
	Zooms so that the given spread rectangle completely fills the current DocView view extents. By default this function will call the End() function for this operation afterwards.
void	ZoomAtPoint (const WorkCoord &wcZoom, FIXED16 fxNewScaleFactor, BOOL fEndOp=TRUE)
	Sets the current DocView to show the given point at the given scale factor. By default this function will call the End() function for this operation afterwards.
void	ZoomAtPoint (Spread *pZoomSpread, const DocCoord &dcZoomPos, FIXED16 fxNewScaleFactor, BOOL fEndOp=TRUE)
void	MouseWheelZoomAtPoint (const WorkCoord &wcZoom, FIXED16 fxNewScalePercent, BOOL fEndOp=TRUE)
	Sets the current DocView to show the given point at the given scale factor. By default this function will call the End() function for this operation afterwards.
Static Public Member Functions
static void	SpreadToWork (Spread *pspdIn, const DocCoord &dcIn, WorkCoord *pwcOut)
static void	SpreadToWork (Spread *pspdIn, const DocRect &drIn, WorkRect *pwrOut)
static INT32	GetPresetZoomPercent (INT32 nPreset)
static FIXED16	GetPresetZoomScale (INT32 nPreset)
static BOOL	Declare ()
	"Registers" the zoom operation's OpDescriptors, loads preferences, and makes sure the zoom-in and zoom-out cursors are valid.
Private Member Functions
BOOL	OnDragStarted (Spread *, const DocCoord &, ClickModifiers)
	Called by OpZoom's base class, OpDragBox, when a drag has been started. Sets the status line text to a helpful comment.
BOOL	OnPointerMoved (Spread *, const DocRect &, ClickModifiers)
	If this function is called then a drag has definitely started, so update the status bar. We don't do this on a button-down event.
BOOL	OnDragEnded (Spread *pBoxSpread, const DocRect &drDragBox, ClickModifiers cmods, BOOL fDragOK)
DocRect	CalcDragBox (const DocCoord &dcStartPos, const DocCoord &dcMousePos) const
	Overrides the default OpDragBox method to allow the drag box to be drawn from the centre (start of drag) to the corner (current mouse position), if the 'ZoomDragOnCentre' preference allows. If it doesn't the default method is called instead.
BOOL	GetStatusLineText (String_256 *ptext, Spread *, DocCoord, ClickModifiers)
	get status line help for zoom drag op
	CC_DECLARE_DYNCREATE (OpZoom)
Private Attributes
Cursor	m_csrZoomIn
Cursor	m_csrZoomOut
Cursor	m_csrZoomDrag
INT32	m_ncsrSaveDrag
WorkCoord	m_wcStartPos
BOOL	m_fStatusTextShown
Static Private Attributes
static INT32	ZoomTable [cZoomTableSize]
static BOOL	m_fRadialZoomDragBox = FALSE
	Determines how the zoom drag operation invokes by the zoom tool will draw its drag box. If FALSE (the default) then the tool will draw the box from one corner to its opposite. This is similar to the selector's drag box. If TRUE then the tool will draw its centre box centred on the point where the drag started and extending to the current mouse position. The effect is to centre the zoom on the first clicked point.
static BOOL	m_fFixZoomClickPoint = FALSE
	When zooming in or out with a mouse click, this determines whether to fix the clicked point in the resulting zoomed view at the same screen-relative position, or to centre the zoomed view on the clicked point. By default this is FALSE (don't fix, do centre).
static UINT32	m_nfShowZoomCursors = 0
	Determines whether to flash a "zooming-in" or "zooming-out" cursor when a zoom is being calculated, and a special drag cursor when dragging in the zoom tool.

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Detailed Description

This operation can perform zooms in and out of the current DocView, either by an immediate call to the ZoomIn/ZoomOut/ZoomInOnRect/ZoomAtPoint functions, or by a call to the DoDrag function, which starts a mouse drag to define a zoom box.

Author:

Justin_Flude (Xara Group Ltd) <camelotdev@xara.com>

Date:

23/4/95

Definition at line 166 of file zoomops.h.

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Constructor & Destructor Documentation

OpZoom::OpZoom (   )

Default constructor. To run a zoom drag, call the DoDrag() function. Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Date: 23/4/95 Definition at line 249 of file zoomops.cpp. : m_csrZoomIn((Tool_v1*)NULL, _R(IDCSR_ZOOM_IN)), // we only need these cursors when an OpZoom m_csrZoomOut((Tool_v1*)NULL, _R(IDCSR_ZOOM_OUT)), m_csrZoomDrag((Tool_v1*)NULL, _R(IDCSR_ZOOM_DRAG)) // is going to be run { // ERROR3IF(!m_csrZoomIn.IsValid() || !m_csrZoomOut.IsValid() || !m_csrZoomDrag.IsValid(), // "Failed to load cursor(s) in OpZoom::OpZoom"); }

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Member Function Documentation

DocRect OpZoom::CalcDragBox (  const DocCoord &  dcStartPos, const DocCoord &  dcMousePos )  const [private, virtual]

Overrides the default OpDragBox method to allow the drag box to be drawn from the centre (start of drag) to the corner (current mouse position), if the 'ZoomDragOnCentre' preference allows. If it doesn't the default method is called instead. Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Date: 23/4/95 Parameters: dcStartPos  the position where the drag was started [INPUTS] dcMousePos the current position of the mouse Returns: A document (spread) rectangle the is the current bounds of the drag box. See also: OpDragBox::CalcDragBox Reimplemented from OpCentredDragBox. Definition at line 571 of file zoomops.cpp. { // Do what the preferences say. return (m_fRadialZoomDragBox) ? OpCentredDragBox::CalcDragBox(dcStartPos, dcMousePos) : OpDragBox::CalcDragBox(dcStartPos, dcMousePos); }

OpZoom::CC_DECLARE_DYNCREATE (  OpZoom   )  [private]

BOOL OpZoom::Declare (   )  [static]

"Registers" the zoom operation's OpDescriptors, loads preferences, and makes sure the zoom-in and zoom-out cursors are valid. Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Date: 23/4/95 Returns: TRUE if everything went OK, FALSE otherwise See also: class OpZoomComboDescriptor; class OpZoomPrevZoomDescriptor; class OpZoomFitSpreadDescriptor; class OpZoomFitDrawingDescriptor Definition at line 1044 of file zoomops.cpp. { // Try to create OpDescriptors for each zoom gadget. ERRORIF(!new OpZoomComboDescriptor || !new OpZoomPrevZoomDescriptor || !new OpZoomFitSpreadDescriptor || !new OpZoomFitDrawingDescriptor || !new OpZoomFitSelectedDescriptor || !new OpZoomFitRectDescriptor || !OpZoomTo100::Init() || !OpZoomTo200::Init() || !OpZoomTo300::Init() || !OpZoomTo400::Init(), _R(IDE_NOMORE_MEMORY), FALSE); #if !defined(EXCLUDE_FROM_RALPH) // Try to load preferences. ERRORIF(!GetApplication()->DeclareSection(TEXT("Zoom Tool"), 5) || !GetApplication()->DeclarePref(TEXT("Zoom Tool"), TEXT("FixZoomClickPoint"), &m_fFixZoomClickPoint, FALSE, TRUE) || !GetApplication()->DeclarePref(TEXT("Zoom Tool"), TEXT("RadialZoomDragBox"), &m_fRadialZoomDragBox, FALSE, TRUE) || !GetApplication()->DeclarePref(TEXT("Zoom Tool"), TEXT("ShowZoomCursors"), &m_nfShowZoomCursors, 0, 1), _R(IDE_BAD_INI_FILE), FALSE); #endif // Success. return TRUE; }

void OpZoom::Do (  OpDescriptor *  pOpDesc  )  [virtual]

Performs the zoom operation. Author: Neville_Humphrys (Xara Group Ltd) <camelotdev@xara.com> Date: 20/9/95 Parameters: pointer  to the OpZoomDescriptor being invoked [INPUTS] See also: OpZoomDescriptor::FakeInvoke; Reimplemented from Operation. Reimplemented in OpZoomIn, OpZoomOut, OpZoomTo100, OpZoomTo200, OpZoomTo300, and OpZoomTo400. Definition at line 270 of file zoomops.cpp. { // Do what FakeInvoke does but call the DoZoom function instead of HandleButtonMsg for // the zoom descriptor. OpZoomDescriptor* pZoomOpDesc = (OpZoomDescriptor*) pOpDesc; if (pZoomOpDesc != 0 && pZoomOpDesc->IsAvailable()) { // DoZoom function must End the operation. pZoomOpDesc->DoZoom(this); } }

BOOL OpZoom::DoDrag (  Spread *  pStartSpread, const DocCoord &  dcStartPos, ClickModifiers  cmods )

Starts an auto-scroll drag operation at the given mouse position. Note that this function hides the base-class DoDrag() function. Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Date: 23/4/95 Parameters: pStartSpread  the spread containing the initial mouse postion [INPUTS] dcStartPos the initial mosue position, ie, where the drag started cmods the state of the mouse modifier keys See also: OpDragBox::DoDrag Definition at line 391 of file zoomops.cpp. { return OpDragBox::DoDrag(DRAGTYPE_AUTOSCROLL, pStartSpread, dcStartPos, cmods); }

INT32 OpZoom::GetPresetZoomPercent (  INT32  nPreset  )  [static]

Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Date: 24/4/95 Parameters: nPreset  which preset zoom factor, with 0 the highest and [INPUTS] cZoomTableSize-1 the lowest. Returns: A standard preset zoom factor, as a percentage. Definition at line 347 of file zoomops.cpp. { ERROR3IF(nPreset < 0 || nPreset >= cZoomTableSize, "Bad preset in OpZoom::GetPresetZoomPercent"); return ZoomTable[nPreset]; }

FIXED16 OpZoom::GetPresetZoomScale (  INT32  nPreset  )  [static]

Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Date: 24/4/95 Parameters: nPreset  which preset zoom factor, with 0 the highest and [INPUTS] cZoomTableSize-1 the lowest. Returns: A standard preset zoom factor, as a scale factor. Definition at line 367 of file zoomops.cpp. { ERROR3IF(nPreset < 0 || nPreset >= cZoomTableSize, "Bad preset in OpZoom::GetPresetZoomScale"); return ((FIXED16) ZoomTable[nPreset]) / 100; }

BOOL OpZoom::GetStatusLineText (  String_256 *  pText, Spread *  , DocCoord  , ClickModifiers  )  [private, virtual]

get status line help for zoom drag op Author: Ed_Cornes (Xara Group Ltd) <camelotdev@xara.com> Date: 26/1/95 Parameters: Spread*,DocCoord,ClickModifiers  - not used [INPUTS] pText  - [OUTPUTS] Returns: TRUE if returning valid text Errors: this==0 Reimplemented from Operation. Definition at line 1023 of file zoomops.cpp. { ERROR2IF(this == 0, FALSE, "OpZoom::GetStatusLineText() - this == 0"); ERROR2IF(pText == 0, FALSE, "OpZoom::GetStatusLineText() - pText == 0"); return pText->Load(_R(IDS_ZOOMOP_STATUSHELP)); }

void OpZoom::MouseWheelZoomAtPoint (  const WorkCoord &  wcZoom, FIXED16  fxNewScaleFactor, BOOL  fEndOp = TRUE )

Sets the current DocView to show the given point at the given scale factor. By default this function will call the End() function for this operation afterwards. Author: Priestley (Xara Group Ltd) <camelotdev@xara.com> (BLATANTLY ripped from JustinF & Rik) Date: 17/11/2000 Parameters: wcZoom  the point within the current view to zoom at, [INPUTS] in work coordinates. fxNewScaleFactor the required scale factor fEndOp whether to end this operation after this zoom Definition at line 1094 of file zoomops.cpp. { // Get the current view. DocView* pDocView = DocView::GetCurrent(); ERROR3IF(pDocView == 0, "No current DocView in OpZoom::ZoomAtPoint"); // Save the view's current zoom and find out current scaling factor. OpZoomPrevZoomDescriptor::SaveZoom(pDocView); FIXED16 fxOldScaleFactor = pDocView->GetViewScale(); // Push the zoom-in or zoom-out cursor, depending on whether we are zooming in or // out. INT32 ncsrOldID=0; if (ZoomTool::IsSelectedTool() && m_nfShowZoomCursors) { ncsrOldID = CursorStack::GPush((fxNewScaleFactor > fxOldScaleFactor) ? &m_csrZoomIn : &m_csrZoomOut); } // Find the current view size in 64-bit work coordinates. WorkRect wrView = pDocView->GetViewRect(); // Work out the ratio of the new and old scale factors. double fpLineRatio = fxOldScaleFactor.MakeDouble() / fxNewScaleFactor.MakeDouble(); // We either centre the clicked point or keep it fixed, depending on the preferences. // Calculate the new position of the top-left of the view accordingly. WorkCoord wcNewTopCorner = wcZoom; // if (!m_fFixZoomClickPoint) // { // Find the vector from the click point to the top corner of the window, and // from this work out the new position of the top-left corner of the view. wcNewTopCorner.x += XLONG(fpLineRatio * (wrView.lo.x - wcZoom.x)); wcNewTopCorner.y += XLONG(fpLineRatio * (wrView.hi.y - wcZoom.y)); // } // else // { // // Find the vector from the centre of the view to the top-left corner, scaled by // // the line-ratio. Add this vector to the click point to work out the new position // // of the top-left corner of the view. // wcNewTopCorner.x -= MakeXLong(fpLineRatio * (wrView.Width().MakeDouble() / 2)); // wcNewTopCorner.y += MakeXLong(fpLineRatio * (wrView.Height().MakeDouble() / 2)); // } // Scale the value to the correct number of pixels. We convert to doubles as the // fixed-point numbers can lose precision at high zooms. double fpPixRatio = fxNewScaleFactor.MakeDouble() / fxOldScaleFactor.MakeDouble(); wcNewTopCorner.x = XLONG(fpPixRatio * wcNewTopCorner.x); wcNewTopCorner.y = XLONG(fpPixRatio * wcNewTopCorner.y); // Set the new scale factor in the view. pDocView->SetViewScale(fxNewScaleFactor); // Make sure that the new scroll offset is within workspace bounds and set it. if (wcNewTopCorner.x < 0) wcNewTopCorner.x = 0; if (wcNewTopCorner.y > 0) wcNewTopCorner.y = 0; pDocView->SetScrollOffsets(wcNewTopCorner, FALSE); #ifndef RALPH // Update the combo-box containing scale factors. OpZoomComboDescriptor::Update(); #endif // Finally redraw the whole window, reset the cursor, and end the operation. pDocView->ForceRedraw(TRUE); if (ZoomTool::IsSelectedTool() && m_nfShowZoomCursors) CursorStack::GPop(ncsrOldID); if (fEndOp) End(); // tell people things have changed on screen TRACEUSER( "Diccon", _T("ZoomAtPoint\n")); BROADCAST_TO_ALL(ScreenChangeMsg(TRUE)); }

BOOL OpZoom::OnDragEnded (  Spread *  pBoxSpread, const DocRect &  drDragBox, ClickModifiers  cmods, BOOL  fDragOK )  [private, virtual]

Reimplemented from OpDragBox. Definition at line 477 of file zoomops.cpp. { // Pop the cursor we possibly pushed in OnStartDrag. if (m_nfShowZoomCursors) CursorStack::GPop(m_ncsrSaveDrag); // If the drag didn't happen we do nothing. We don't want FailAndExecute() called // though, so return TRUE. if (!fDragOK) return TRUE; // This could take a while . . . // BeginSlowJob(); // Get the current view. DocView* pDocView = DocView::GetCurrent(); ERROR3IF(pDocView == 0, "No current DocView in OpZoom::OnDragEnded"); // Find the half of the absolute width and height of the drag box. WorkCoord wcLast = pDocView->GetClickWorkCoord(); WorkRect wrZoom; if (m_fRadialZoomDragBox) { XLONG nWidth2 = m_wcStartPos.x - wcLast.x; if (nWidth2 < 0) nWidth2 = -nWidth2; XLONG nHeight2 = m_wcStartPos.y - wcLast.y; if (nHeight2 < 0) nHeight2 = -nHeight2; // Make a rectangle of this width and height, centred on the click point. wrZoom = WorkRect(m_wcStartPos.x - nWidth2, m_wcStartPos.y - nHeight2, m_wcStartPos.x + nWidth2, m_wcStartPos.y + nHeight2); } else { #undef MIN #undef MAX #define MIN(a,b) (((a)<(b))?(a):(b)) #define MAX(a,b) (((a)>(b))?(a):(b)) wrZoom = WorkRect(MIN(m_wcStartPos.x, wcLast.x), MIN(m_wcStartPos.y, wcLast.y), MAX(m_wcStartPos.x, wcLast.x), MAX(m_wcStartPos.y, wcLast.y)); } // We must first check if we have a significant drag box. If the size of the box // is less than the Camelot "click radius" we will ignore the drag and treat the // operation as a single-click "zoom in" action by the user. // Graeme (11/11/99): The comparison is now done against a constant value // (ZOOM_MIN_DRAG), which is defined in zoomops.h. dDragDistance gives an absolute // value, rather than testing against separate x and y values. // Zoom in bug fixed by Chris Snook/Graeme (14/12/99) .... double dDragDistance = sqrt ( ( (double) wrZoom.Width () * (double) wrZoom.Width () ) + ( (double) wrZoom.Height () * (double) wrZoom.Height () ) ); if ( dDragDistance < ZOOM_MIN_DRAG || wrZoom.Width() <= 0 || wrZoom.Height() <= 0 ) { // Drag is insignificant so zoom in instead. ZoomIn(m_wcStartPos, FALSE); // OpDragBox will end this op } else { // Do a proper mouse-drag zoom. ZoomInOnRect(wrZoom, FALSE); // OpDragBox will end this op } // tell people things have changed on screen TRACEUSER( "Diccon", _T("OnDragEnded\n")); BROADCAST_TO_ALL(ScreenChangeMsg(TRUE)); // Remove the hour-glass and return the success code. // EndSlowJob(); return TRUE; }

BOOL OpZoom::OnDragStarted (  Spread *  , const DocCoord &  , ClickModifiers  )  [private, virtual]

Called by OpZoom's base class, OpDragBox, when a drag has been started. Sets the status line text to a helpful comment. Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Date: 23/4/95 Parameters: (not  used) [INPUTS] Returns: TRUE (always) Reimplemented from OpDragBox. Definition at line 409 of file zoomops.cpp. { // Remember where the drag started. We have to "bodge" this as it is apparently too // difficult to translate document coordinates to work coordinates during a drag, so // we can't use the mouse position info passed to us by the OpDragBox base-class. DocView* pDocView = DocView::GetCurrent(); ERROR3IF(pDocView == 0, "No current DocView in OpZoom::OnDragStarted"); m_wcStartPos = pDocView->GetClickWorkCoord(); // Reset this flag. m_fStatusTextShown = FALSE; // Possibly set the zoom-cursor, saving the old one, and return success. if (m_nfShowZoomCursors) m_ncsrSaveDrag = CursorStack::GPush(&m_csrZoomDrag); return TRUE; }

BOOL OpZoom::OnPointerMoved (  Spread *  , const DocRect &  , ClickModifiers  )  [private, virtual]

If this function is called then a drag has definitely started, so update the status bar. We don't do this on a button-down event. Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Date: 24/6/95 Parameters: (not  used) [INPUTS] Returns: TRUE, meaning continue dragging. Reimplemented from OpDragBox. Definition at line 439 of file zoomops.cpp. { #if !defined(EXCLUDE_FROM_RALPH) // The first time through this function set the status-line text. We don't really // want to do this on a button-down event as not all such events lead to drags. if (!m_fStatusTextShown) { // Set the status line text. If we manage to do it then don't bother doing it // again until another drag really begins. String_256 str(_R(IDS_ZOOMOP_STATUSHELP)); m_fStatusTextShown = GetApplication()->UpdateStatusBarText(&str); } #endif // All fine, continue dragging. return TRUE; }

virtual BOOL OpZoom::SnappingDrag (   )  [inline, virtual]

Reimplemented from Operation. Definition at line 187 of file zoomops.h. { return FALSE; }

void OpZoom::SpreadToWork (  Spread *  pspdIn, const DocRect &  drIn, WorkRect *  pwrOut )  [static]

Definition at line 327 of file zoomops.cpp. { // Convert low and high corners of the rectangle. SpreadToWork(pspdIn, drIn.lo, &pwrOut->lo); SpreadToWork(pspdIn, drIn.hi, &pwrOut->hi); }

void OpZoom::SpreadToWork (  Spread *  pspdIn, const DocCoord &  dcIn, WorkCoord *  pwcOut )  [static]

Definition at line 297 of file zoomops.cpp. { // Caller must provide a location to store the converted coordinate. ERROR3IF(pwcOut == 0, "No output in OpZoom::SpreadToWork"); // Find the current DocView. DocView* pDocView = DocView::GetCurrent(); ERROR3IF(pDocView == 0, "No current DocView in OpZoom::SpreadToWork"); // Convert. if (pDocView && pwcOut) *pwcOut = ((DocCoord&) dcIn).ToWork(pspdIn, pDocView); }

void OpZoom::ZoomAtPoint (  Spread *  pZoomSpread, const DocCoord &  dcZoomPos, FIXED16  fxNewScaleFactor, BOOL  fEndOp = TRUE )

Definition at line 1000 of file zoomops.cpp. { // Now we can just pass to the WorkCoord version of this function. WorkCoord wcZoom; SpreadToWork(pZoomSpread, dcZoomPos, &wcZoom); ZoomAtPoint(wcZoom, fxNewScaleFactor, fEndOp); }

void OpZoom::ZoomAtPoint (  const WorkCoord &  wcZoom, FIXED16  fxNewScaleFactor, BOOL  fEndOp = TRUE )

Sets the current DocView to show the given point at the given scale factor. By default this function will call the End() function for this operation afterwards. Technical notes: What the zoom does. This routine finds out the current scroll offsets and makes a vector from the clicked point to the top corner of the window (ie the scroll offsets). It knows the ratio of the old scale factor and the new scale factor and uses this to calculate a new point from the click point along the vector. For example, if the ratio of the old and new zooms is one half then the new top corner of the window will be a point on the vector, half way between the click point and the old top corner of the window. Since the document will be changing size and since the scroll offsets are measured in pixels, these will be changing after the zoom has happened, so we have to compensate for that as well. All that remains to do after that is check that the offsets are valid and then set them. Definition at line 908 of file zoomops.cpp. { // Get the current view. DocView* pDocView = DocView::GetCurrent(); ERROR3IF(pDocView == 0, "No current DocView in OpZoom::ZoomAtPoint"); // Save the view's current zoom and find out current scaling factor. OpZoomPrevZoomDescriptor::SaveZoom(pDocView); FIXED16 fxOldScaleFactor = pDocView->GetViewScale(); // Push the zoom-in or zoom-out cursor, depending on whether we are zooming in or // out. INT32 ncsrOldID=0; if (ZoomTool::IsSelectedTool() && m_nfShowZoomCursors) { ncsrOldID = CursorStack::GPush((fxNewScaleFactor > fxOldScaleFactor) ? &m_csrZoomIn : &m_csrZoomOut); } // Find the current view size in 64-bit work coordinates. WorkRect wrView = pDocView->GetViewRect(); // Work out the ratio of the new and old scale factors. double fpLineRatio = fxOldScaleFactor.MakeDouble() / fxNewScaleFactor.MakeDouble(); // We either centre the clicked point or keep it fixed, depending on the preferences. // Calculate the new position of the top-left of the view accordingly. WorkCoord wcNewTopCorner = wcZoom; if (m_fFixZoomClickPoint) { // Find the vector from the click point to the top corner of the window, and // from this work out the new position of the top-left corner of the view. wcNewTopCorner.x += XLONG(fpLineRatio * (wrView.lo.x - wcZoom.x)); wcNewTopCorner.y += XLONG(fpLineRatio * (wrView.hi.y - wcZoom.y)); } else { // Find the vector from the centre of the view to the top-left corner, scaled by // the line-ratio. Add this vector to the click point to work out the new position // of the top-left corner of the view. wcNewTopCorner.x -= XLONG(fpLineRatio * wrView.Width ()/2); wcNewTopCorner.y += XLONG(fpLineRatio * wrView.Height()/2); } // Scale the value to the correct number of pixels. We convert to doubles as the // fixed-point numbers can lose precision at high zooms. double fpPixRatio = fxNewScaleFactor.MakeDouble() / fxOldScaleFactor.MakeDouble(); wcNewTopCorner.x = XLONG(fpPixRatio * wcNewTopCorner.x); wcNewTopCorner.y = XLONG(fpPixRatio * wcNewTopCorner.y); // Set the new scale factor in the view. pDocView->SetViewScale(fxNewScaleFactor); // Make sure that the new scroll offset is within workspace bounds and set it. if (wcNewTopCorner.x < 0) wcNewTopCorner.x = 0; if (wcNewTopCorner.y > 0) wcNewTopCorner.y = 0; pDocView->SetScrollOffsets(wcNewTopCorner, FALSE); #ifndef RALPH // Update the combo-box containing scale factors. OpZoomComboDescriptor::Update(); #endif // Finally redraw the whole window, reset the cursor, and end the operation. pDocView->ForceRedraw(TRUE); if (ZoomTool::IsSelectedTool() && m_nfShowZoomCursors) CursorStack::GPop(ncsrOldID); if (fEndOp) End(); // tell people things have changed on screen TRACEUSER( "Diccon", _T("ZoomAtPoint\n")); BROADCAST_TO_ALL(ScreenChangeMsg(TRUE)); }

void OpZoom::ZoomIn (  Spread *  pZoomSpread, const DocCoord &  dcZoomPos, BOOL  fEndOp = TRUE )

Zooms in on the current DocView by one step. By default this function will call the End() function for this operation afterwards. Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Date: 23/4/95 Parameters: pZoomSpread  the spread containing the point to zoom in at [INPUTS] dcZoomPos the point to zoom in at fEndOp whether to end this operation after this zoom Definition at line 733 of file zoomops.cpp. { WorkCoord wcZoom; SpreadToWork(pZoomSpread, dcZoomPos, &wcZoom); ZoomIn(wcZoom, fEndOp); }

void OpZoom::ZoomIn (  const WorkCoord &  wcZoom, BOOL  fEndOp = TRUE )

Zooms into the current DocView by one step. By default this function will call the End() function for this operation afterwards. Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Date: 23/4/95 Parameters: wcZoom  the point to zoom in at [INPUTS] fEndOp whether to end this operation after this zoom Definition at line 688 of file zoomops.cpp. { // Find out the current view. DocView* pDocView = DocView::GetCurrent(); ERROR3IF(pDocView == 0, "No current DocView in OpZoom::ZoomIn"); if (pDocView) { // Find the current view's scaling factor. By converting this to a percentage // and rounding we improve the accuracy of the comparison below. INT32 nOldScalePercent = ((pDocView->GetViewScale() * 100) + FIXED16_DBL(0.5)).MakeInt(); // Search backwards until we find a higher zoom, or the end of the table (meaning that // there is no higher zoom). for (INT32 i = cZoomTableSize - 1; i >= 0; i--) { // Found a higher zoom? If so, set it, remember it's position and return. if (nOldScalePercent < GetPresetZoomPercent(i)) { // Do the zoom. We will (optionally) end the operation. pDocView->SetZoomTableIndex(i); ZoomAtPoint(wcZoom, GetPresetZoomScale(i), FALSE); break; } } } // End the operation if the caller wants us to. if (fEndOp) End(); }

void OpZoom::ZoomInOnRect (  Spread *  pZoomSpread, const DocRect &  drZoomRect, BOOL  fEndOp = TRUE )

Zooms so that the given spread rectangle completely fills the current DocView view extents. By default this function will call the End() function for this operation afterwards. Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Date: 23/4/95 Parameters: pZoomSpread  the spread containing the rectangle to zoom in on [INPUTS] drZoomRect the rectangle to zoom in on. fEndOp whether to end this operation after this zoom Definition at line 867 of file zoomops.cpp. { // Call the WorkRect version of this function to do the zoom. WorkRect wrZoom; SpreadToWork(pZoomSpread, drZoomRect, &wrZoom); ZoomInOnRect(wrZoom, fEndOp); }

void OpZoom::ZoomInOnRect (  const WorkRect &  wrZoom, BOOL  fEndOp = TRUE )

Zooms so that the given work rectangle completely fills the current DocView view extents. By default this function will call the End() function for this operation afterwards. Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Date: 23/4/95 Parameters: wrZoom  the rectangle to zoom in on. [INPUTS] fEndOp whether to end this operation after this zoom Definition at line 754 of file zoomops.cpp. { // Make sure the zoom rectangle isn't empty, or we'll divide by zero later on. if (wrZoom.IsEmpty()) { ERROR3("Empty zoom rectangle passed to OpZoom::ZoomInOnRect"); return; } // Find out the current view and save its scale factor and scroll offsets. DocView* pDocView = DocView::GetCurrent(); ERROR3IF(pDocView == 0, "No current DocView in OpZoom::ZoomInOnRect"); // Get out now if view 0 otherwise we will access violate later on if (pDocView == 0) return; OpZoomPrevZoomDescriptor::SaveZoom(pDocView); // Find out the size of the window and the given zoom rectangle in work coordinates. WorkRect wrView = pDocView->GetViewRect(); // Get the current scale factor. double fpOldScaleFactor = pDocView->GetViewScale().MakeDouble(); // Find out the ratios of the width and height (zoom rect to view rect). We know // that the divisors are not zero, or we would not have entered this function. double fpWidthFactor = (double)wrView.Width ()/wrZoom.Width (); double fpHeightFactor = (double)wrView.Height()/wrZoom.Height(); double fpMinFactor = (fpWidthFactor < fpHeightFactor) ? fpWidthFactor : fpHeightFactor; // The new zoom factor is proportional to the above double fpNewScaleFactor = fpOldScaleFactor * fpMinFactor; // Push the zoom-in or zoom-out cursor, depending on whether we are zooming in or // out and the state of the preference. INT32 ncsrOldID=0; if (ZoomTool::IsSelectedTool() && m_nfShowZoomCursors) { ncsrOldID = CursorStack::GPush((fpNewScaleFactor > fpOldScaleFactor) ? &m_csrZoomIn : &m_csrZoomOut); } // Convert the new scale factor to a percentage and check that it's in bounds. If it // isn't adjust it to the lowest/highest zoom factors. INT32 nZoomPercent = (INT32) (fpNewScaleFactor * 100); if (nZoomPercent < GetPresetZoomPercent(cZoomTableSize - 1)) { fpNewScaleFactor = GetPresetZoomScale(cZoomTableSize - 1).MakeDouble(); } else if (nZoomPercent > GetPresetZoomPercent(0)) { fpNewScaleFactor = GetPresetZoomScale(0).MakeDouble(); } // Set the scroll offsets to the middle of the box. WorkCoord wcScrollOffset; wcScrollOffset.x = (wrZoom.lo.x + wrZoom.hi.x) / 2; wcScrollOffset.y = (wrZoom.lo.y + wrZoom.hi.y) / 2; // Scale the value to the correct number of pixels. double fpRatio = fpNewScaleFactor / fpOldScaleFactor; wcScrollOffset.x = XLONG(wcScrollOffset.x*fpRatio); wcScrollOffset.y = XLONG(wcScrollOffset.y*fpRatio); // Offset it by half the size of the window. WHY? AND WHY THE MakeLong() CALL? wcScrollOffset.x = wcScrollOffset.x - (wrView.Width() / 2); wcScrollOffset.y += wrView.Height() / 2; // Check the scroll offsets bounds as we can't have scroll offsets anywhere. if (wcScrollOffset.x < 0) wcScrollOffset.x = 0; if (wcScrollOffset.y > 0) wcScrollOffset.y = 0; // Set the scale. This must be done before the scroll offset is set or // strangeness will follow . . . pDocView->SetViewScale((FIXED16) fpNewScaleFactor); pDocView->SetScrollOffsets(wcScrollOffset, FALSE); // Update the combo-box containing scale factors. pDocView->SetZoomTableIndex(cFractionalZoomIndex); #ifndef RALPH OpZoomComboDescriptor::Update(); #endif // We have to force a redraw as the zoom has changed, reset the cursor, and end the // operation. pDocView->ForceRedraw(TRUE); if (ZoomTool::IsSelectedTool() && m_nfShowZoomCursors) CursorStack::GPop(ncsrOldID); if (fEndOp) End(); // tell people things have changed on screen TRACEUSER( "Diccon", _T("ZoomInOnRect\n")); BROADCAST_TO_ALL(ScreenChangeMsg(TRUE)); }

void OpZoom::ZoomOut (  Spread *  pZoomSpread, const DocCoord &  dcZoomPos, BOOL  fEndOp = TRUE )

Zooms out of the current DocView by one step. By default this function will call the End() function for this operation afterwards. Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Date: 23/4/95 Parameters: pZoomSpread  the spread containing the point to zoom out at [INPUTS] dcZoomPos the point to zoom out at fEndOp whether to end this operation after this zoom Definition at line 640 of file zoomops.cpp. { WorkCoord wcZoom; SpreadToWork(pZoomSpread, dcZoomPos, &wcZoom); ZoomOut(wcZoom, fEndOp); }

void OpZoom::ZoomOut (  const WorkCoord &  wcZoom, BOOL  fEndOp = TRUE )

Zooms out of the current DocView by one step. By default this function will call the End() function for this operation afterwards. Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Date: 23/4/95 Parameters: wcZoom  the point to zoom out at [INPUTS] fEndOp whether to end this operation after this zoom Definition at line 591 of file zoomops.cpp. { // Find out the current view. DocView* pDocView = DocView::GetCurrent(); ERROR3IF(pDocView == 0, "No selected DocView in OpZoom::ZoomOut"); if (pDocView) { // Get the current view's scaling factor as a rounded precentage. INT32 nOldScalePercent = ((pDocView->GetViewScale() * 100) + FIXED16_DBL(0.5)).MakeInt(); // Search forwards through the zoom table until we find a lower zoom factor, or // until we hit the end of the table, meaning no lower zoom factor exists. for (INT32 i = 0; i < cZoomTableSize; i++) { // Found a lower zoom? If so, set it, remember it's position in the zoom table // and return. if (nOldScalePercent > GetPresetZoomPercent(i)) { // Do the zoom. We will (optionally) end the operation. pDocView->SetZoomTableIndex(i); ZoomAtPoint(wcZoom, GetPresetZoomScale(i), FALSE); break; } } } // We must correctly end the operation. if (fEndOp) End(); // tell people things have changed on screen TRACEUSER( "Diccon", _T("ZoomOut\n")); BROADCAST_TO_ALL(ScreenChangeMsg(TRUE)); }

void OpZoom::ZoomTo (  const WorkCoord &  wcZoom, INT32  nPercent, BOOL  fEndOp = TRUE )

Zooms into the current DocView by one step. By default this function will call the End() function for this operation afterwards. Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Date: 23/4/95 Parameters: wcZoom  the point to zoom in at [INPUTS] fEndOp whether to end this operation after this zoom Definition at line 659 of file zoomops.cpp. { // Find out the current view. DocView* pDocView = DocView::GetCurrent(); ERROR3IF(pDocView == 0, "No current DocView in OpZoom::ZoomIn"); if (pDocView) { // Do the zoom. We will (optionally) end the operation. FIXED16 f16Scale = FIXED16(nPercent) / 100; ZoomAtPoint(wcZoom, f16Scale, FALSE); } // End the operation if the caller wants us to. if (fEndOp) End(); }

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Member Data Documentation

Cursor OpZoom::m_csrZoomDrag [private]

Definition at line 232 of file zoomops.h.

Cursor OpZoom::m_csrZoomIn [private]

Definition at line 230 of file zoomops.h.

Cursor OpZoom::m_csrZoomOut [private]

Definition at line 231 of file zoomops.h.

BOOL OpZoom::m_fFixZoomClickPoint = FALSE [static, private]

When zooming in or out with a mouse click, this determines whether to fix the clicked point in the resulting zoomed view at the same screen-relative position, or to centre the zoomed view on the clicked point. By default this is FALSE (don't fix, do centre). Preference: FixZoomClickPoint Section: Zoom Tool Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Range: FALSE or TRUE Definition at line 242 of file zoomops.h.

BOOL OpZoom::m_fRadialZoomDragBox = FALSE [static, private]

Determines how the zoom drag operation invokes by the zoom tool will draw its drag box. If FALSE (the default) then the tool will draw the box from one corner to its opposite. This is similar to the selector's drag box. If TRUE then the tool will draw its centre box centred on the point where the drag started and extending to the current mouse position. The effect is to centre the zoom on the first clicked point. Preference: RadialZoomDragBox Section: Zoom Tool Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Range: FALSE or TRUE Definition at line 241 of file zoomops.h.

BOOL OpZoom::m_fStatusTextShown [private]

Definition at line 235 of file zoomops.h.

INT32 OpZoom::m_ncsrSaveDrag [private]

Definition at line 233 of file zoomops.h.

UINT32 OpZoom::m_nfShowZoomCursors = 0 [static, private]

Determines whether to flash a "zooming-in" or "zooming-out" cursor when a zoom is being calculated, and a special drag cursor when dragging in the zoom tool. Preference: ShowZoomInOutCursors Section: Zoom Tool Author: Justin_Flude (Xara Group Ltd) <camelotdev@xara.com> Range: 0 ... 1 Some people think this adds a groovy, polished feel to the program. Others don't, which is why this preference is 0 by default (ie. no special zoom cursors). Definition at line 243 of file zoomops.h.

WorkCoord OpZoom::m_wcStartPos [private]

Definition at line 234 of file zoomops.h.

INT32 OpZoom::ZoomTable [static, private]

Initial value: { 25601, 16000, 8000, 4000, 2000, 1000, 500, 200, 100, 75, 50, 25, 10, } Definition at line 238 of file zoomops.h.

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The documentation for this class was generated from the following files:

• tools/zoomops.h (r1785/r1771)
• tools/zoomops.cpp (r1785/r1771)

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