ah so it was that simple. thanks for that.
About the bump mapping… i didn’t know you needed a high res lightmap for it to be
noticable, i’m still learning about this stuff.
Is it the same with phong shading… higher lightmap res = better results?
nope
phong lighting works by smoothing the light between two places not on the same orientation. in other words where you have an angle on the terrain. the terrain is still drawn in the same way and shape but the smooth lighting hides the edges and seams on the angles between the brushes so the terrain looks smoother and more like its one whole lump of earth rather then made up of smaller triangles
on current lightmaps ull find the resolution of the lightmap is much smaller then the resolution of the image its going over. if it was the same you would need to save a light pixel for every pixel of texture in the map. this is clearly overkill and you would end up with too much lightmap data
bump mapping is where light is effected accross one surface. if you imagine a bump in a surface then the side of the bump facing the light source is might brighter and the side facing away is much darker. this information could be saved into the lightmaps but because they are such low resolution you dont have the presision to save the information. you could increase the lightmap of a particualr surface and bumpmap it since you would be limiting the increase in lightmaps. although the benefi of bumpmaping just one surface is questionable and you run the risk of this surface looking out of place in comparison to the rest of the map
for modern engine like doom3 lighting is not pre porcesed into lightmap but generated in real time per pixel meaning you can bumpmap pretty much everything since you dont need to store massise of high res lightmaps
afaik some have made modifications to quake3/quake2 engine that stores the direction light is hitting a surface as well as the lightmaps on the surface. meaning surfaces can be bumpmaped but the highs/lows in the lughting will be created at run time rather then pre procesed. but its unlikly that you will be developing for one of these engines
:???: