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Qt Image on label

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  • G Offline
    G Offline
    Gayathri
    wrote on last edited by
    #5

    Yes it is a QLabel with pixmap and then i use painter and drawText for the dialog . I set the font size

    const QPixmap *orig_bg = canvas_bg_img->pixmap();
    QImage orig_bg_img = orig_bg->toImage();

    QPainter p(&orig_bg_img);
    
    QRect rect(0,350,640,200);
    p.drawRect(rect);
    p.fillRect(rect, QBrush(QColor(0, 0, 0, 128)));
    
    p.setPen(QColor(200,200,180));
    
    
    QRect rect1(50,350, 800, 300);
    QFont font1 = p.font() ;
    font1.setPointSize(12);
    /* set the modified font to the painter */
    p.setFont(font1);
    p.drawText(rect1,Qt::TextWordWrap,narrator);
    
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    • mrjjM Offline
      mrjjM Offline
      mrjj
      Lifetime Qt Champion
      wrote on last edited by
      #6

      ok. thank you for code.
      So even with this code, it sometimes is way bigger than 12 points?

      I wonder if some of the images makes setPointSize scale.
      Can you try with
      void QFont::setPixelSize(int pixelSize)
      and see if it still makes big text sometimes.
      Then we know why it happens.

      G 1 Reply Last reply
      1
      • G Offline
        G Offline
        Gayathri
        wrote on last edited by
        #7

        Ok i will try that

        1 Reply Last reply
        0
        • mrjjM Offline
          mrjjM Offline
          mrjj
          Lifetime Qt Champion
          wrote on last edited by
          #8

          oh I forgot to ask.
          Can you make it draw big text each time if u use the image that does it?
          I mean, is it repeatable ?

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          0
          • G Offline
            G Offline
            Gayathri
            wrote on last edited by
            #9

            yes every time i use that background pic ..it is big !

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            • G Offline
              G Offline
              Gayathri
              wrote on last edited by
              #10

              Hi. SetPixel size worked !!!!!! Could you explain to me why is that so ?

              mrjjM 1 Reply Last reply
              0
              • mrjjM mrjj

                ok. thank you for code.
                So even with this code, it sometimes is way bigger than 12 points?

                I wonder if some of the images makes setPointSize scale.
                Can you try with
                void QFont::setPixelSize(int pixelSize)
                and see if it still makes big text sometimes.
                Then we know why it happens.

                G Offline
                G Offline
                Gayathri
                wrote on last edited by
                #11

                @mrjj

                Setpixel size worked ! ... Could u explain as to why this worked

                Also i have another question.

                Now i have textwrap for my text in drawtext. But it does go out of view. Is it possible to change font to fit the size of the space i have ???? . Changing font dynamically depending on the size of the dialogue and the space

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                • G Gayathri

                  Hi. SetPixel size worked !!!!!! Could you explain to me why is that so ?

                  mrjjM Offline
                  mrjjM Offline
                  mrjj
                  Lifetime Qt Champion
                  wrote on last edited by mrjj
                  #12

                  @Gayathri
                  Super.
                  Well setPointSize is relative to resolution of the device/surface.
                  so when you say 12. it will try to make that look like 12 across many different
                  screens. Its call device independent.

                  setPixelSizeon the other hand just use the value you give it so
                  on other screen, it might look much smaller.

                  so I think setPointSize somehow thinks that your big image is much higher res
                  and then try to help you scale the font.

                  ++ change font to fit the size
                  Well you can code it yes.
                  using
                  QFontMetrics fm(myFont);
                  int width=fm.width(str);
                  you can get size info about what you draw
                  so you can check if it fits inside the rect you have.
                  if NOT, then you can reduce font size and try again
                  until it fits.

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                  • G Offline
                    G Offline
                    Gayathri
                    wrote on last edited by
                    #13

                    Thanks a lot @mrjj. You were of great help !

                    mrjjM 1 Reply Last reply
                    0
                    • G Gayathri

                      Thanks a lot @mrjj. You were of great help !

                      mrjjM Offline
                      mrjjM Offline
                      mrjj
                      Lifetime Qt Champion
                      wrote on last edited by
                      #14

                      @Gayathri
                      Super. Please mark as solved if possible.

                      Final note:
                      if you make a loop to find font size then make sure
                      to make a counter guard to exit if looping too many times.
                      while ( TestSize(FontSize,str)==false & count++ < 100) {
                      FontSize--;
                      }
                      So you dont hang your app if u ever get a text that just cannot fit :)

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                      • G Offline
                        G Offline
                        Gayathri
                        wrote on last edited by
                        #15

                        sure i will ...thanks mrjj

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