Qt Graphics Effects (Graphics Effect) Introduction to __qt/graphics images

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Qgraphicseffect is also a new feature introduced by Qt-4.6. It is easy to give graphical elements Qgraphicsitem programming to add better visual effects.

Let's take a look at some of the effects.

The top of the picture above is not using qgraphicseffect processing of the original image, the following four pictures represent the blur, discoloration, transparency and shadow effects. Corresponds to the use of the Qgraphicseffect 4 subclasses Qgraphicsblureffect, Qgraphicscolorizeeffect, Qgraphicsdropshadoweffect, and Qgraphicsopacityeffect. Introduce them separately below.

Qgraphicsblureffect
This class should produce fuzzy effect, the main function Setblurradius (Qreal Blurradius), used to control the ambiguity of graphic elements, the larger the number of fuzzy. Use this class example as follows

Qgraphicsblureffect *e0 = new Qgraphicsblureffect (this);
E0->setblurradius (0.2);
Item[0]->setgraphicseffect (E1);//item[0] as Qgraphicsitem pointer

Qgraphicscolorizeeffect
This class provides a shading function for the current graphic using another color. The primary functions are SetColor (Qcolor) and setstrength (Qreal strength), which specify the coloring and shading intensities. Use this class example as follows

Qgraphicscolorizeeffect *e1 = new Qgraphicscolorizeeffect (this);
E1->setcolor (Qcolor (0,0,192));
Item[1]->setgraphicseffect (E1);

Qgraphicsdropshadoweffect
This class provides shadow effects for graphical elements to increase the icing on the stereo. The main setup functions are 3, setcolor () is used to set the color of the Shadow, Setblurradius () is used to set the blur of the Shadow, SetOffset (Qreal dx,qreal dy) is used to set the direction in which the shadow effect, if DX is negative, The shadow is on the left side of the graphic element. Use this class example as follows

Qgraphicsdropshadoweffect *e2 = new Qgraphicsdropshadoweffect (this);
E2->setoffset (8,8);
Item[2]->setgraphicseffect (E2);

Qgraphicsopacityeffect
This class is used for transparent effects of graphical elements, and the primary function is setopacity (qreal opacity), which is used to set transparency, with parameter values between 0 and 1.0. You can also set a partial transparency effect, and the function you need to call is Setopacitymask (Qbrush mask). Use this class example as follows

Qgraphicsopacityeffect *e3 = new Qgraphicsopacityeffect (this);
E3->setopacity (0.7);
Item[3]->setgraphicseffect (E3);

Below I am writing the example code and screenshot.

Finally, it is worth mentioning that these effects can be combined with each other. If you can combine these effects with QT's animated animation API, the programs you write are even more beautiful.
$QTSRC/examples/effect Directory There are some examples to refer to below.

From:http://blog.sina.com.cn/s/blog_66e717d70100hare.html