Hi, I’m still pretty much a ROOT newbie, so any direction is appreciated.
I have a program which displays a large jpeg and then uses putpixel to draw user defined arrays over the image. This works fine, although if I use img->Draw(), then draw more pixels, I can’t get the pad to update correctly unless I Unzoom with my mouse or resize the canvas. Also, if I clear and/or update the pad and/or canvas, then use img->Draw(), I get the same results. It seems like the img itself is stored in a buffer somewhere that doesn’t get updated until an event like UnZoom occurs, but I can’t figure out exactly why.
Ultimately, I’m trying to make an event display which can display arbitrary shapes (events) over this image which can be clicked on, as well as the ability to update them as well. I’m not sure TGImageMap can do what I need, largely because I need the ability to zoom as well, so that’s why I’m doing it this way. Also, the image is very large, 3500x3000 pixels.