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/*
* This program source code file is part of KiCad, a free EDA CAD application.
*
* Copyright (C) 2013-2016 CERN
* Copyright (C) 2020 KiCad Developers, see AUTHORS.txt for contributors.
*
* @author Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, you may find one here:
* http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
* or you may search the http://www.gnu.org website for the version 2 license,
* or you may write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#ifndef __VIEW_H
#define __VIEW_H
#include <vector>
#include <set>
#include <unordered_map>
#include <memory>
#include <math/box2.h>
#include <gal/definitions.h>
#include <view/view_overlay.h>
#include <view/view.h>
class EDA_ITEM;
namespace KIGFX
{
class PAINTER;
class GAL;
class VIEW_ITEM;
class VIEW_GROUP;
class VIEW_RTREE;
/**
* Hold a (potentially large) number of VIEW_ITEMs and renders them on a graphics device
* provided by the GAL.
*
* VIEWs can exist in two flavors:
* - dynamic - where items can be added, removed or changed anytime, intended for the main
* editing panel. Each VIEW_ITEM can be added to a single dynamic view.
* - static - where items are added once at the startup and are not linked with the VIEW.
* Foreseen for preview windows and printing.
*
* Items in a view are grouped in layers (not to be confused with Kicad's PCB layers). Each
* layer is identified by an integer number. Visibility and rendering order can be set
* individually for each of the layers. Future versions of the VIEW will also allows one to
* assign different layers to different rendering targets, which will be composited at the
* final stage by the GAL. The VIEW class also provides fast methods for finding all visible
* objects that are within a given rectangular area, useful for object selection/hit testing.
*/
class VIEW
{
public:
friend class VIEW_ITEM;
typedef std::pair<VIEW_ITEM*, int> LAYER_ITEM_PAIR;
/**
* @param aIsDynamic decides whether we are creating a static or a dynamic VIEW.
*/
VIEW( bool aIsDynamic = true );
virtual ~VIEW();
/**
* Nasty hack, invoked by the destructor of VIEW_ITEM to auto-remove the item
* from the owning VIEW if there is any.
*
* KiCad relies too much on this mechanism. This is the only linking dependency now
* between #EDA_ITEM and VIEW class. In near future I'll replace it with observers.
*/
static void OnDestroy( VIEW_ITEM* aItem );
/**
* Add a #VIEW_ITEM to the view.
*
* Set \a aDrawPriority to -1 to assign sequential priorities.
*
* @param aItem: item to be added. No ownership is given
* @param aDrawPriority: priority to draw this item on its layer, lowest first.
*/
virtual void Add( VIEW_ITEM* aItem, int aDrawPriority = -1 );
/**
* Remove a #VIEW_ITEM from the view.
*
* @param aItem: item to be removed. Caller must dispose the removed item if necessary
*/
virtual void Remove( VIEW_ITEM* aItem );
/**
* Find all visible items that touch or are within the rectangle \a aRect.
*
* @param aRect area to search for items
* @param aResult result of the search, containing VIEW_ITEMs associated with their layers.
* Sorted according to the rendering order (items that are on top of the
* rendering stack as first).
* @return Number of found items.
*/
virtual int Query( const BOX2I& aRect, std::vector<LAYER_ITEM_PAIR>& aResult ) const;
/**
* Set the item visibility.
*
* @param aItem: the item to modify.
* @param aIsVisible: whether the item is visible (on all layers), or not.
*/
void SetVisible( VIEW_ITEM* aItem, bool aIsVisible = true );
/**
* Temporarily hide the item in the view (e.g. for overlaying).
*
* @param aItem: the item to modify.
* @param aHide: whether the item is hidden (on all layers), or not.
*/
void Hide( VIEW_ITEM* aItem, bool aHide = true );
/**
* Return information if the item is visible (or not).
*
* @param aItem: the item to test.
* @return when true, the item is visible (i.e. to be displayed, not visible in the
* *current* viewport)
*/
bool IsVisible( const VIEW_ITEM* aItem ) const;
/**
* For dynamic VIEWs, inform the associated VIEW that the graphical representation of
* this item has changed. For static views calling has no effect.
*
* @param aItem: the item to update.
* @param aUpdateFlags: how much the object has changed.
*/
virtual void Update( const VIEW_ITEM* aItem, int aUpdateFlags ) const;
virtual void Update( const VIEW_ITEM* aItem ) const;
/**
* Mark the \a aRequiredId layer as required for the aLayerId layer. In order to display the
* layer, all of its required layers have to be enabled.
*
* @param aLayerId is the id of the layer for which we enable/disable the required layer.
* @param aRequiredId is the id of the required layer.
* @param aRequired tells if the required layer should be added or removed from the list.
*/
void SetRequired( int aLayerId, int aRequiredId, bool aRequired = true );
/**
* Copy layers and visibility settings from another view.
*
* @param aOtherView: view from which settings will be copied.
*/
void CopySettings( const VIEW* aOtherView );
/*
* Convenience wrappers for adding multiple items
* template <class T> void AddItems( const T& aItems );
* template <class T> void RemoveItems( const T& aItems );
*/
/**
* Assign a rendering device for the VIEW.
*
* @param aGal: pointer to the GAL output device.
*/
void SetGAL( GAL* aGal );
/**
* Return the #GAL this view is using to draw graphical primitives.
*
* @return Pointer to the currently used GAL instance.
*/
inline GAL* GetGAL() const
{
return m_gal;
}
/**
* Set the painter object used by the view for drawing #VIEW_ITEMS.
*/
inline void SetPainter( PAINTER* aPainter )
{
m_painter = aPainter;
}
/**
* Return the painter object used by the view for drawing #VIEW_ITEMS.
*
* @return Pointer to the currently used Painter instance.
*/
inline PAINTER* GetPainter() const
{
return m_painter;
}
/**
* Set the visible area of the VIEW.
*
* @param aViewport: desired visible area, in world space coordinates.
*/
void SetViewport( const BOX2D& aViewport );
/**
* Return the current viewport visible area rectangle.
*
* @return Current viewport rectangle.
*/
BOX2D GetViewport() const;
/**
* Control the mirroring of the VIEW.
*
* @param aMirrorX: when true, the X axis is mirrored.
* @param aMirrorY: when true, the Y axis is mirrored.
*/
void SetMirror( bool aMirrorX, bool aMirrorY );
/**
* Return true if view is flipped across the X axis.
*/
bool IsMirroredX() const
{
return m_mirrorX;
}
/**
* Return true if view is flipped across the Y axis.
*/
bool IsMirroredY() const
{
return m_mirrorY;
}
/**
* Set the scaling factor, zooming around a given anchor point.
*
* (depending on correct GAL unit length & DPI settings).
*
* @param aAnchor is the zooming anchor point.
* @param aScale is the scale factor.
*/
virtual void SetScale( double aScale, VECTOR2D aAnchor = { 0, 0 } );
/**
* @return Current scale factor of this VIEW.
*/
inline double GetScale() const
{
return m_scale;
}
/**
* Set limits for view area.
*
* @param aBoundary is the box that limits view area.
*/
inline void SetBoundary( const BOX2D& aBoundary )
{
m_boundary = aBoundary;
}
/**
* Set limits for view area.
*
* @param aBoundary is the box that limits view area.
*/
inline void SetBoundary( const BOX2I& aBoundary )
{
m_boundary.SetOrigin( aBoundary.GetOrigin() );
m_boundary.SetEnd( aBoundary.GetEnd() );
}
/**
* @return Current view area boundary.
*/
inline const BOX2D& GetBoundary() const
{
return m_boundary;
}
/**
* Set minimum and maximum values for scale.
*
* @param aMaximum is the maximum value for scale.
* @param aMinimum is the minimum value for scale.
*/
void SetScaleLimits( double aMaximum, double aMinimum )
{
wxASSERT_MSG( aMaximum > aMinimum, wxT( "I guess you passed parameters in wrong order" ) );
m_minScale = aMinimum;
m_maxScale = aMaximum;
}
/**
* Set the center point of the VIEW (i.e. the point in world space that will be drawn in
* the middle of the screen).
*
* @param aCenter: the new center point, in world space coordinates.
*/
void SetCenter( const VECTOR2D& aCenter );
/**
* Set the center point of the VIEW, attempting to avoid \a occultingScreenRect (for
* instance, the screen rect of a modeless dialog in front of the VIEW).
*
* @param aCenter: the new center point, in world space coordinates.
* @param occultingScreenRect: the occulting rect, in screen space coordinates.
*/
void SetCenter( const VECTOR2D& aCenter, const BOX2D& occultingScreenRect );
/**
* Return the center point of this VIEW (in world space coordinates).
*
* @return center point of the view
*/
const VECTOR2D& GetCenter() const
{
return m_center;
}
/**
* Converts a screen space point/vector to a point/vector in world space coordinates.
*
* @param aCoord is the point/vector to be converted.
* @param aAbsolute when true aCoord is treated as a point, otherwise as a direction (vector).
*/
VECTOR2D ToWorld( const VECTOR2D& aCoord, bool aAbsolute = true ) const;
/**
* Converts a screen space one dimensional size to a one dimensional size in world
* space coordinates.
*
* @param aSize is the size to be converted.
*/
double ToWorld( double aSize ) const;
/**
* Convert a world space point/vector to a point/vector in screen space coordinates.
*
* @param aCoord is the point/vector to be converted.
* @param aAbsolute when true aCoord is treated as a point, otherwise as a direction (vector).
*/
VECTOR2D ToScreen( const VECTOR2D& aCoord, bool aAbsolute = true ) const;
/**
* Convert a world space one dimensional size to a one dimensional size in screen space.
*
* @param aSize: the size to be transformed.
*/
double ToScreen( double aSize ) const;
/**
* Return the size of the our rendering area in pixels.
*
* @return viewport screen size.
*/
const VECTOR2I& GetScreenPixelSize() const;
/**
* Remove all items from the view.
*/
void Clear();
/**
* Control the visibility of a particular layer.
*
* @param aLayer is the layer to show/hide.
* @param aVisible is the layer visibility state.
*/
inline void SetLayerVisible( int aLayer, bool aVisible = true )
{
wxCHECK( aLayer < (int) m_layers.size(), /*void*/ );
if( m_layers[aLayer].visible != aVisible )
{
// Target has to be redrawn after changing its visibility
MarkTargetDirty( m_layers[aLayer].target );
m_layers[aLayer].visible = aVisible;
}
}
/**
* Return information about visibility of a particular layer.
*
* @param aLayer true if the layer is visible, false otherwise.
*/
inline bool IsLayerVisible( int aLayer ) const
{
wxCHECK( aLayer >= 0, false);
wxCHECK( aLayer < (int) m_layers.size(), false );
return m_layers.at( aLayer ).visible;
}
/**
* Set the whether the layer should drawn differentially.
*
* @param aLayer is the layer to set to be draw differentially
* @param aDiff is the layer diff'ing state.
*/
inline void SetLayerDiff( int aLayer, bool aDiff = true )
{
wxCHECK( aLayer < (int) m_layers.size(), /*void*/ );
if( m_layers[aLayer].diffLayer != aDiff )
{
// Target has to be redrawn after changing its layers' diff status
MarkTargetDirty( m_layers[aLayer].target );
m_layers[aLayer].diffLayer = aDiff;
}
}
/**
* Set the status of negatives presense in a particular layer.
*
* @param aLayer is the layer to set as containing negatives (or not).
* @param aNegatives is the layer negatives state.
*/
inline void SetLayerHasNegatives( int aLayer, bool aNegatives = true )
{
wxCHECK( aLayer < (int) m_layers.size(), /*void*/ );
if( m_layers[aLayer].hasNegatives != aNegatives )
{
// Target has to be redrawn after changing a layers' negatives
MarkTargetDirty( m_layers[aLayer].target );
m_layers[aLayer].hasNegatives = aNegatives;
}
}
inline void SetLayerDisplayOnly( int aLayer, bool aDisplayOnly = true )
{
wxCHECK( aLayer < (int) m_layers.size(), /*void*/ );
m_layers[aLayer].displayOnly = aDisplayOnly;
}
/**
* Change the rendering target for a particular layer.
*
* @param aLayer is the layer.
* @param aTarget is the rendering target.
*/
inline void SetLayerTarget( int aLayer, RENDER_TARGET aTarget )
{
wxCHECK( aLayer < (int) m_layers.size(), /*void*/ );
m_layers[aLayer].target = aTarget;
}
/**
* Set rendering order of a particular layer. Lower values are rendered first.
*
* @param aLayer is the layer.
* @param aRenderingOrder is an arbitrary number denoting the rendering order.
*/
void SetLayerOrder( int aLayer, int aRenderingOrder );
/**
* Return rendering order of a particular layer. Lower values are rendered first.
*
* @param aLayer is the layer.
* @return Rendering order of a particular layer.
*/
int GetLayerOrder( int aLayer ) const;
/**
* Change the order of given layer ids, so after sorting the order corresponds to layers
* rendering order (descending, ie. order in which layers should be drawn - from the bottom to
* the top).
*
* @param aLayers stores id of layers to be sorted.
* @param aCount stores the number of layers.
*/
void SortLayers( int aLayers[], int& aCount ) const;
/**
* Remap the data between layer ids without invalidating that data.
*
* Used by GerbView for the "Sort by X2" functionality.
*
* @param aReorderMap is a mapping of old to new layer ids.
*/
void ReorderLayerData( std::unordered_map<int, int> aReorderMap );
/**
* Apply the new coloring scheme held by RENDER_SETTINGS in case that it has changed.
*
* @param aLayer is a number of the layer to be updated.
* @see RENDER_SETTINGS
*/
void UpdateLayerColor( int aLayer );
/**
* Apply the new coloring scheme to all layers. The used scheme is held by #RENDER_SETTINGS.
*
* @see RENDER_SETTINGS
*/
void UpdateAllLayersColor();
/**
* Set given layer to be displayed on the top or sets back the default order of layers.
*
* @param aEnabled = true to display aLayer on the top.
* @param aLayer is the layer or -1 in case when no particular layer should be displayed
* on the top.
*/
virtual void SetTopLayer( int aLayer, bool aEnabled = true );
/**
* Enable or disable display of the top layer.
*
* When disabled, layers are rendered as usual with no influence from SetTopLayer
* function. Otherwise on the top there is displayed the layer set previously with
* SetTopLayer function.
*
* @param aEnable whether to enable or disable display of the top layer.
*/
virtual void EnableTopLayer( bool aEnable );
virtual int GetTopLayer() const;
/**
* Remove all layers from the on-the-top set (they are no longer displayed over the rest of
* layers).
*/
void ClearTopLayers();
/**
* Do everything that is needed to apply the rendering order of layers.
*
* It has to be called after modification of renderingOrder field of LAYER.
*/
void UpdateAllLayersOrder();
/**
* Clear targets that are marked as dirty.
*/
void ClearTargets();
/**
* Immediately redraws the whole view.
*/
virtual void Redraw();
/**
* Rebuild GAL display lists.
*/
void RecacheAllItems();
/**
* Tell if the VIEW is dynamic (ie. can be changed, for example displaying PCBs in a window)
* or static (that cannot be modified, eg. displaying image/PDF).
*/
bool IsDynamic() const
{
return m_dynamic;
}
/**
* Return true if any of the VIEW layers needs to be refreshened.
*
* @return True in case if any of layers is marked as dirty.
*/
bool IsDirty() const
{
for( int i = 0; i < TARGETS_NUMBER; ++i )
{
if( IsTargetDirty( i ) )
return true;
}
return false;
}
/**
* Return true if any of layers belonging to the target or the target itself should be
* redrawn.
*
* @return True if the above condition is fulfilled.
*/
bool IsTargetDirty( int aTarget ) const
{
wxCHECK( aTarget < TARGETS_NUMBER, false );
return m_dirtyTargets[aTarget];
}
/**
* Set or clear target 'dirty' flag.
*
* @param aTarget is the target to set.
*/
inline void MarkTargetDirty( int aTarget )
{
wxCHECK( aTarget < TARGETS_NUMBER, /* void */ );
m_dirtyTargets[aTarget] = true;
}
/// Return true if the layer is cached.
inline bool IsCached( int aLayer ) const
{
wxCHECK( aLayer < (int) m_layers.size(), false );
try
{
return m_layers.at( aLayer ).target == TARGET_CACHED;
}
catch( const std::out_of_range& )
{
return false;
}
}
/**
* Force redraw of view on the next rendering.
*/
void MarkDirty()
{
for( int i = 0; i < TARGETS_NUMBER; ++i )
m_dirtyTargets[i] = true;
}
/**
* Force redraw of view on the next rendering.
*/
void MarkClean()
{
for( int i = 0; i < TARGETS_NUMBER; ++i )
m_dirtyTargets[i] = false;
}
/**
* Add an item to a list of items that are going to be refreshed upon the next frame rendering.
*
* @param aItem is the item to be refreshed.
*/
void MarkForUpdate( VIEW_ITEM* aItem );
/**
* Iterate through the list of items that asked for updating and updates them.
*/
void UpdateItems();
/**
* Update all items in the view according to the given flags.
*
* @param aUpdateFlags is is according to KIGFX::VIEW_UPDATE_FLAGS
*/
void UpdateAllItems( int aUpdateFlags );
/**
* Update items in the view according to the given flags and condition.
*
* @param aUpdateFlags is is according to KIGFX::VIEW_UPDATE_FLAGS.
* @param aCondition is a function returning true if the item should be updated.
*/
void UpdateAllItemsConditionally( int aUpdateFlags,
std::function<bool( VIEW_ITEM* )> aCondition );
/**
* @return true if draw priority is being respected while redrawing.
*/
bool IsUsingDrawPriority() const
{
return m_useDrawPriority;
}
/**
* @param aFlag is true if draw priority should be respected while redrawing.
*/
void UseDrawPriority( bool aFlag )
{
m_useDrawPriority = aFlag;
}
/**
* @return true if draw order is reversed
*/
bool IsDrawOrderReversed() const
{
return m_reverseDrawOrder;
}
/**
* Only takes effect if UseDrawPriority is true.
*
* @param aFlag is true if draw order should be reversed
*/
void ReverseDrawOrder( bool aFlag )
{
m_reverseDrawOrder = aFlag;
}
std::shared_ptr<VIEW_OVERLAY> MakeOverlay();
void InitPreview();
void ClearPreview();
void AddToPreview( EDA_ITEM* aItem, bool aTakeOwnership = true );
void ShowPreview( bool aShow = true );
/**
* Return a new VIEW object that shares the same set of VIEW_ITEMs and LAYERs.
*
* GAL, PAINTER and other properties are left uninitialized.
*/
std::unique_ptr<VIEW> DataReference() const;
static constexpr int VIEW_MAX_LAYERS = 512; ///< maximum number of layers that may be shown
protected:
struct VIEW_LAYER
{
bool visible; ///< Is the layer to be rendered?
bool displayOnly; ///< Is the layer display only?
bool diffLayer; ///< Layer should be drawn differentially over lower layers
bool hasNegatives; ///< Layer should be drawn separately to not delete lower layers
std::shared_ptr<VIEW_RTREE> items; ///< R-tree indexing all items on this layer.
int renderingOrder; ///< Rendering order of this layer.
int id; ///< Layer ID.
RENDER_TARGET target; ///< Where the layer should be rendered.
std::set<int> requiredLayers; ///< Layers that have to be enabled to show
///< the layer.
};
VIEW( const VIEW& ) = delete;
///* Redraws contents within rect aRect
void redrawRect( const BOX2I& aRect );
inline void markTargetClean( int aTarget )
{
wxCHECK( aTarget < TARGETS_NUMBER, /* void */ );
m_dirtyTargets[aTarget] = false;
}
/**
* Draw an item, but on a specified layers.
*
* It has to be marked that some of drawing settings are based on the layer on which
* an item is drawn.
*
* @param aItem is the item to be drawn.
* @param aLayer is the layer which should be drawn.
* @param aImmediate dictates the way of drawing - it allows one to force immediate
* drawing mode for cached items.
*/
void draw( VIEW_ITEM* aItem, int aLayer, bool aImmediate = false );
/**
* Draw an item on all layers that the item uses.
*
* @param aItem is the item to be drawn.
* @param aImmediate dictates the way of drawing - it allows one to force immediate
* drawing mode for cached items.
*/
void draw( VIEW_ITEM* aItem, bool aImmediate = false );
/**
* Draw a group of items on all layers that those items use.
*
* @param aGroup is the group to be drawn.
* @param aImmediate dictates the way of drawing - it allows one to force immediate
* drawing mode for cached items.
*/
void draw( VIEW_GROUP* aGroup, bool aImmediate = false );
///< Sort m_orderedLayers when layer rendering order has changed
void sortLayers();
///< Clear cached GAL group numbers (*ONLY* numbers stored in VIEW_ITEMs, not group objects
///< used by GAL)
void clearGroupCache();
/**
* Manage dirty flags & redraw queuing when updating an item.
*
* @param aItem is the item to be updated.
* @param aUpdateFlags determines the way an item is refreshed.
*/
void invalidateItem( VIEW_ITEM* aItem, int aUpdateFlags );
///< Update colors that are used for an item to be drawn
void updateItemColor( VIEW_ITEM* aItem, int aLayer );
///< Update all information needed to draw an item
void updateItemGeometry( VIEW_ITEM* aItem, int aLayer );
///< Update bounding box of an item
void updateBbox( VIEW_ITEM* aItem );
///< Update set of layers that an item occupies
void updateLayers( VIEW_ITEM* aItem );
///< Determine rendering order of layers. Used in display order sorting function.
static bool compareRenderingOrder( VIEW_LAYER* aI, VIEW_LAYER* aJ )
{
return aI->renderingOrder > aJ->renderingOrder;
}
///< Check if every layer required by the aLayerId layer is enabled.
bool areRequiredLayersEnabled( int aLayerId ) const;
// Function objects that need to access VIEW/VIEW_ITEM private/protected members
struct CLEAR_LAYER_CACHE_VISITOR;
struct RECACHE_ITEM_VISITOR;
struct DRAW_ITEM_VISITOR;
struct UPDATE_COLOR_VISITOR;
struct UPDATE_DEPTH_VISITOR;
std::unique_ptr<KIGFX::VIEW_GROUP> m_preview;
std::vector<EDA_ITEM *> m_ownedItems;
///< Whether to use rendering order modifier or not.
bool m_enableOrderModifier;
///< The set of possible displayed layers and its properties.
std::vector<VIEW_LAYER> m_layers;
///< Sorted list of pointers to members of m_layers.
std::vector<VIEW_LAYER*> m_orderedLayers;
///< Flat list of all items.
std::shared_ptr<std::vector<VIEW_ITEM*>> m_allItems;
///< The set of layers that are displayed on the top.
std::set<unsigned int> m_topLayers;
///< Center point of the VIEW (the point at which we are looking at).
VECTOR2D m_center;
///< Scale of displayed VIEW_ITEMs.
double m_scale;
///< View boundaries.
BOX2D m_boundary;
///< Scale lower limit.
double m_minScale;
///< Scale upper limit.
double m_maxScale;
///< Horizontal flip flag.
bool m_mirrorX;
///< Vertical flip flag.
bool m_mirrorY;
///< PAINTER contains information how do draw items.
PAINTER* m_painter;
///< Interface to #PAINTER that is used to draw items.
GAL* m_gal;
///< Dynamic VIEW (eg. display PCB in window) allows changes once it is built,
///< static (eg. image/PDF) - does not.
bool m_dynamic;
///< Flag to mark targets as dirty so they have to be redrawn on the next refresh event.
bool m_dirtyTargets[TARGETS_NUMBER];
///< Rendering order modifier for layers that are marked as top layers.
static const int TOP_LAYER_MODIFIER;
///< Flag to respect draw priority when drawing items.
bool m_useDrawPriority;
///< The next sequential drawing priority.
int m_nextDrawPriority;
///< Flag to reverse the draw order when using draw priority.
bool m_reverseDrawOrder;
};
} // namespace KIGFX
#endif
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