so. now we have the point where you are wrong. and its in fact the topic
you are RIGHT with your idea how to get a value that helps to adjust the exposurefactor. i never stated thats a bad idea. i never stated thats a bad idea to sum up what you see, because thats how the eye does it.
you’re not right as well that i did not provided you a solution to the problem. i gave you a solution, you just don’t believe its one. but it works, i’ve tested this, nutty tested this. we used it for glowing / blurring of the screen. but all you need to know is, you can with recursive scaling down the texture get the average color. and this average color is a very good starting point to get your exposure-factor. for the rest, i’ll suggest you take a piece of paper and a pen and draw some curves of exposurefunctions and try to find a way how to adjust the constant factor of it. how to do that i don’t know, we can discuss this if you want (i bet you want to ).
the suggestion of the other, summing up the specular visible objects, is good as well. in fact, what he suggests is doing the same i suggested, but doing it offline, in your scene, instead from your screen. why this? because a) you have floatingpoint there and b) well, thats about it…
the suggestion of the other has the problem that it is not a perfect solution but more of a stochastical approach. a) he suggests to only use the bright objects, the specular hightighs in fact, b) you normally don’t know exactly what is on your screen, and how big the speculars are, so how bright in the end they are…
problem of my approach is once again, old hardware. because you render the colordata wich gets yet clamped, you’ll **** your result up, if you have too much values clamped down to 1. but you could a) use this as a feature, not as a bug or b) search another way…
how to use it as a feature:
say your sum-up is more than .5, that means half or your pixels will be 1 (possibly!). that means, about half of your pixels could be clamped. so dark the image a bit down. next time you do the same etc… that way your eye needs time to adjust for big changes… means the sum is say bigger.5 you make it darker, if its lower .1 make it more bright. that is a statistical approach wich, i bet, fits very good to the eye, because that don’t know the values as well, just oh ****, there are a lot of cells on the max-brightness => close the lense. oh ****, most of the cells are not used at all =>open the lense. without knowing how much…
thats more text than i wanted to write