com.trolltech.qt.gui
Class QGraphicsView.OptimizationFlag

java.lang.Object
  java.lang.Enum
      com.trolltech.qt.gui.QGraphicsView.OptimizationFlag

All Implemented Interfaces:

QtEnumerator, java.io.Serializable, java.lang.Comparable

Enclosing class:

QGraphicsView

public static final class QGraphicsView.OptimizationFlag
extends java.lang.Enum
implements QtEnumerator

This enum describes flags that you can enable to improve rendering performance in QGraphicsView. By default, none of these flags are set. Note that setting a flag usually imposes a side effect, and this effect can vary between paint devices and platforms.

See Also:

Serialized Form

Field Summary

static QGraphicsView.OptimizationFlag	DontAdjustForAntialiasing Disables QGraphicsView's antialiasing auto-adjustment of exposed areas.
static QGraphicsView.OptimizationFlag	DontClipPainter QGraphicsView sometimes clips the painter when rendering the scene contents.
static QGraphicsView.OptimizationFlag	DontSavePainterState When rendering, QGraphicsView protects the painter state (see QPainter::save()) when rendering the background or foreground, and when rendering each item.

Method Summary

static QGraphicsView.OptimizationFlags	createQFlags(QGraphicsView.OptimizationFlag[] values) This function creates a com.trolltech.qt.gui.QGraphicsView$OptimizationFlags with the specified com.trolltech.qt.gui.QGraphicsView$OptimizationFlag[] QGraphicsView$OptimizationFlag values set.
static QGraphicsView.OptimizationFlag	resolve(int value) Returns the QGraphicsView$OptimizationFlag constant with the specified int.
int	value() This function should return an integer value for the enum values of the enumeration that implements this interface.
static QGraphicsView.OptimizationFlag	valueOf(java.lang.String name)
static QGraphicsView.OptimizationFlag[]	values()

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Field Detail

DontClipPainter

public static final QGraphicsView.OptimizationFlag DontClipPainter

QGraphicsView sometimes clips the painter when rendering the scene contents. This can generally improve performance (e.g., rendering only small parts of a large pixmap), and protects against rendering mistakes (e.g., drawing outside bounding rectangles, or outside the exposed area). In some situations, however, the painter clip can slow down rendering; especially when all painting is restricted to inside exposed areas. By enabling this flag, QGraphicsView will completely disable its implicit clipping. Note that rendering artifacts from using a semi-transparent foreground or background brush can occur if clipping is disabled.

DontSavePainterState

public static final QGraphicsView.OptimizationFlag DontSavePainterState

When rendering, QGraphicsView protects the painter state (see QPainter::save()) when rendering the background or foreground, and when rendering each item. This allows you to leave the painter in an altered state (i.e., you can call QPainter::setPen() or QPainter::setBrush() without restoring the state after painting). However, if the items consistently do restore the state, you should enable this flag to prevent QGraphicsView from doing the same.

DontAdjustForAntialiasing

public static final QGraphicsView.OptimizationFlag DontAdjustForAntialiasing

Disables QGraphicsView's antialiasing auto-adjustment of exposed areas. Items that render antialiased lines on the boundaries of their QGraphicsItem::boundingRect() can end up rendering parts of the line outside. To prevent rendering artifacts, QGraphicsView expands all exposed regions by 2 pixels in all directions. If you enable this flag, QGraphicsView will no longer perform these adjustments, minimizing the areas that require redrawing, which improves performance. A common side effect is that items that do draw with antialiasing can leave painting traces behind on the scene as they are moved.

Method Detail

values

public static QGraphicsView.OptimizationFlag[] values()

valueOf

public static QGraphicsView.OptimizationFlag valueOf(java.lang.String name)

value

public int value()

This function should return an integer value for the enum values of the enumeration that implements this interface.

Specified by:

value in interface QtEnumerator

createQFlags

public static QGraphicsView.OptimizationFlags createQFlags(QGraphicsView.OptimizationFlag[] values)

This function creates a com.trolltech.qt.gui.QGraphicsView$OptimizationFlags with the specified com.trolltech.qt.gui.QGraphicsView$OptimizationFlag[] QGraphicsView$OptimizationFlag values set.

resolve

public static QGraphicsView.OptimizationFlag resolve(int value)

Returns the QGraphicsView$OptimizationFlag constant with the specified int.