game developers and in some case animators usually first make their models high poly to add details and then because game engine can't handle too much polys they have to use normal map to transfer the detail to a low poly mesh

here is some example from hitman :






















back then because they had to release the game on consoles too they had to first program the game for those system and then for PC and because old gen consoles had rubbish hardware they had to do this stuff


so on to the next part lads

i'm going to make something like hitman game object that you saw to show you how you can do it as well

now if you going to follow me it dose not matter what shape you make but everything else should be the same


1- first create your shape i did this model :



















2- then duplicate the same model using SHIFT+D and then right click
2-1 rename them one low poly and one high poly just like the photo so you don't mess up later


3- now click on high-poly and hide the low-poly we dont need it new


4- after that you can re-mesh it or subdivide it so you can add the broken part on it
NOTE : more poly better result

1- well this one is easy go to sculpt tab

2- this is the result

1- now get back to the low poly version this time hide the other one



2- select the low poly one and uv unwrap it














3- add new window by doing this










4- open shader editor and hit new







5- press SHIFT+A on empty space

6- from the search bar search for normal map and add it on the shader editor then attach it to the normal on
















7- do the same thing again this time search for image texture and attach it to the color like this

7.5- also add a new image like this if you want your normal map to be higher then 2k like 4k or 8k
add the value to the hight and lengt
NOTE : more value means better depth














8- on normal map node change the color space to non-color

1- open new window for image editor








2- add our normal map to the image editor like this










3- new this part is important go to cycels render engine (aka F-14 start-up code)

1- first select high poly model then select low poly one (this is important)
























2- then find bake option like the photo























3- change the bake type to normal

















4- also enable the selected to active

















5- now you can bake it click on bake and wait until its done

6- after you done you can save it for later

new look at this photo :





this things are called artifacts

how can we get rid of them ?

look at the bake option you find something called EXTURUSION

if the value is set to anything other then 0 it will set a un-visible gap for rays

if the details that you made on high poly model is coming out of low poly model
you have to Measure them and then put the value on exturusion section
there is a ruler on blender on left side use that


but for now you can experiment with exturusion to get the result that you happy with



this is after i set value to 0.001 its fixed now

as you can see on this photo the left on is the low poly and the right one is the high poly one

the one on the left has 14 face and one on the right has 2000 face

if you want to get better depth you have to bake it to a 6k or 8k image texture


enjoy and have great day.

i made another guide about maps that can help you :

https://gtm.you1.cn/sharedfiles/filedetails/?id=2902039824