[Qt-interest] How to render text on Image with different color???

[Robert Hairgrove]

trinathpujari wrote:
> Hi All,
> 
>          I have text drawn on QImage. Now i want to change back ground 
> color as black and text as some other color(selected).I am checking each 
> pixel color and updating the pixel color. But text is becoming distorted.
>     Alternative to this i did invert pixel at that time text is coming 
> properly but Back ground is different(Not black which i wanted).
>          Please help me to resolve this.

Wouldn't it be easier (and possibly faster) to just erase the entire 
background and redraw the text?

The default behaviour for drawing text with QPainter is with 
antialiasing on. Antialiasing blends the edges of the text with the 
background color to provide a smoother perception (i.e. less jagged 
edges). If you need to change the image pixel by pixel, you will 
probably want to turn this off by setting the appropriate property of 
the QFont object before drawing the text (see documentation for the 
QPainter class for details).