[Qt-interest] Changin the pen width for QGLWidget

[Sujan Dasmahapatra]

when I am trying to setPen it crashes.

QPen pen(Qt::blue,8);
paintEngine()->painter()->setPen(pen);
Program received signal SIGSEGV, Segmentation fault.
0x00000000006f895b in QPainter::setPen ()
whats going wrong in this.
On Fri, Dec 4, 2009 at 11:40 AM, 程梁 <chengliang.soft at gmail.com> wrote:

> Because QPainter::pen() function returns const QPen &, so you cannot change
> its attributes using QPainter::pen()'s return.
> You should use QPainter::setPen() with a new QPen instance instead.
>
> 2009/12/4 Sujan Dasmahapatra <sujan.dasmahapatra at gmail.com>
>
>>   Dear Friends
>> I am trying to change the width of the pen which is currently used by the
>> paintEngine() in QGLWidget. For a particular object being drawn I want to
>> increase the width.But it gives error see below.
>> ////////////////////////////////////////////////
>> paintEngine()->painter()->pen().setWidth(8);
>> paintEngine()->painter()->pen().setColor(trolltechPurple);
>> //errors
>> rc/graphicsview_mesh.cpp:852: error: passing `const QPen' as `this'
>> argument of `void QPen::setWidth(int)' discards qualifiers
>> src/graphicsview_mesh.cpp:853: error: passing `const QPen' as `this'
>> argument of `void QPen::setColor(const QColor&)' discards qualifiers
>> Please someone tell what am I doing wrong.
>> I want to increase the width and color for a particular object and after
>> drawing that object I want the width and color to be normal.
>>
>> How can I achieve this. Any help would be appreciated.
>>
>> --
>> Thanks & Regards
>> S. Dasmahapatra
>> B.E. (Aeronautics-Aerodynamics)
>> Software programmer
>> Bangalore, India
>> Ph:91-9900839788
>> Office:91-80-66470248
>> mail id : sujan.dasmahapatra at gmail.com
>>
>> _______________________________________________
>> Qt-interest mailing list
>> Qt-interest at trolltech.com
>> http://lists.trolltech.com/mailman/listinfo/qt-interest
>>
>>
>
>
> --
> Cheng Liang
> from: chengliang.soft at gmail.com
>



-- 
Thanks & Regards
S. Dasmahapatra
B.E. (Aeronautics-Aerodynamics)
Software programmer
Bangalore, India
Ph:91-9900839788
Office:91-80-66470248
mail id : sujan.dasmahapatra at gmail.com
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