DDraceNetwork - developer

@Jupstar ✪ wanted to figure out how the camera width/height is calculated from the aspect ratio. is CRenderTools::CalcScreenParams the correct function, and WMax/32 and HMax32 are the amounts of tiles horizontally/vertically?

01:24

if so, what is Amount supposed to be and what is f with that weird calculation

Patiga

@Jupstar ✪ wanted to figure out how the camera width/height is calculated from the aspect ratio. is CRenderTools::CalcScreenParams the correct function, and WMax/32 and HMax32 are the amounts of tiles horizontally/vertically?

Amount is clear I guess. You want resolution independent scaling. The backend's screen mapping will scale down all variables so we have normalized values across all resolutions, so that you end up in a NDC. Basically how pretty much all projection matrices would also do it. Now sqrt(Amount) is the length of one side of the new resolution. I guess this is clear too? Pretty basic geometric math. Now lets do some math. Imagine we subsitute the Amount at the very last step, even if it breaks math. But we want to transform into a different resolution anyway.. in the resolution of Amount:

x * y = x * y | / y
(x * y) / y = x | * x
(x * y) * (x / y) = x^2 | sqrt
sqrt(x * y) * sqrt(x / y) = x

At this point it's clear where our journey ends xd x / y is the Aspect ratio.. The function takes the Aspect ratio as parameter so our new x is:

x = sqrt(Amount) * sqrt(AspectRatio) 
and y is
y = sqrt(Amount) / sqrt(AspectRatio)
now look at the original formular

float f = sqrtf(Amount) / sqrtf(Aspect);
*w = f * Aspect;
*h = f;

its the exact same. f is basically = y
and we go from y to x by multipling AspectRatio
And AspectRatio / sqrt(AspectRatio) = sqrt(AspectRatio)

You can think about this geometrically too, but I cannot explain it. Draw it on your paper or watch some videos about geometrical mean of sqrt. About WMax and HMax. Basically disallow zooming. And yes / 32 is to get the tile count at normal zoom

There is Patigas twmap which can turn maps into json and back. Do you can track json files in git. (@cauldron)

cauldron

git for map editor when

Maybe a tip for imagination: You want make the new resolution (Amount) fit into our aspect ration So side_length * sqrt(Aspect) and sqrt bcs the AspectRatio is on the "full" old resolution. But you only do the ratio multiplikation on one side of the new resolution not on the full length. E.g. lets say you take 1920x1080 thats the full mass.. EVERYTHING XD if you only want the amount of everything that was created by the width u basicall do (1920×1080) × 16/9 now you have a new mass, the mass of the width do now get the side length of that new mass u simply put a sqrt around it sqrt((1920×1080) × 16/9) and tada. You are back to 1920 See hard to explain but kinda makes sense if u imagine it somehow

06:32

thus the name Aspect Ratio It is the Ratio between the two sides

06:32

xd

06:32

ok i stop now

chillerdragon

There is Patigas twmap which can turn maps into json and back. Do you can track json files in git. (@cauldron)

well you could even track binary files with git, couldn't you? i was thinking of managing soundpacks for ddnet with git, to just checkout another branch and have another soundpack

08:56

but json converter could make building a ddnet map history feature "natively" without git easy

we had an undo manager before just saving the map, its simply very slow

08:57

calculating the diff is not much faster

08:58

would be cleaner to seperate all changes on a map from the editor and do undo events there

what do you mean very slow

08:59

even if its super slow i would use it

as said there was one it was made async bcs it was too slow probs

just saving would be slow, right?