GDIplus - brightness

[Edwin Knoppert]

Yes i seen it, only thing is that the scale/scope differs from the gdiplus effects -1/1 vs -255/255
I have the feeling that a float can not reach the same potential this way (?)

[Patrice Terrier]

Contrast

Code Select Expand


   // factor > 1.0f increases the contrast
   // 0.0f < factor < 1,0f decreases the contrast
   REAL factorT = 0.5f * (1.0f - factor);
   
   ColorMatrix colorMatrix =
   {
      factor,  0.0f,    0.0f,    0.0f, 0.0f,
      0.0f,    factor,  0.0f,    0.0f, 0.0f,
      0.0f,    0.0f,    factor,  0.0f, 0.0f,
      0.0f,    0.0f,    0.0f,    1.0f, 0.0f,
      factorT, factorT, factorT, 0.0f, 1.0f
   };


[Edwin Knoppert]

Somewhere this week i'll continue on this.
I have some other projects interfering

Thanks,

[Edwin Knoppert]

Btw, i was using a trackbar but does not seem to accept negative ranges (-1 <> 1)
I shifted it to positive values but the tracking tooltip shows those values as well.
I wonder if i can use negative values or customly set the value in the tooltip.

Last resort would be to prepare a tracking tooltip from scratch.