Hello Josh, hello everybody,
I come back on a well-known topic: texture baking (or lightmap)
Well, I posted one or two years ago on that topic, and someone (very kind) proposed me a shader, which multiplied the diffuse texture with the baked one.
Here is an extract of the _mesh.frag related to this shader, inserted in the Bloom shader:
//Bloom
#ifdef LW_BLOOM
vec4 bloomcolor = texture2D(LW_BLOOM,texcoord) * fragcolor;
gl_FragData[3] = bloomcolor;
gl_FragData[3].w = 0;
#else
#ifdef LW_GIMAP
vec4 gicolor = texture2D(LW_GIMAP,vec2(texcoord1.x,texcoord1.y));
gicolor *= diffuse;
gicolor.w = 1.0;
gl_FragData[3] = gicolor;
#else
The issue with that algo, is that we do not have exactly the same result with the real-time engine as the “non-realtime”rendering engine (for example mental ray,…).
I searched a lot by myself, and on the Internet. The fact is, when you combine linearly both maps, you will never get the exact result (Example: if you try diffuse*Baked or diffuse+baked, or diffuse*Baked+y*diffuse, etc…)
Here is an example of this, with some pictures (based on a forum post on the game engine “Nova”):
With the “classic algo” Diffuse Map*BakedMap (too dark result):
cf doc file attached...
With the algo Diffuse Map+BakedMap (too bright result):
cf doc file attached...
What we would like:
cf doc file attached...
The proposed algo, which is only an approximation of the wanted result, is the following:
1) For each pixel of Baked Map, convert the value RGB as HSL, and test the V value.
2) If V > 0,5 (in fact, this value can be modified…), perform DiffuseMap+BakedMap for that pixel
3) If V < 0,5 (in fact, this value can be modified…), perform DiffuseMap*BakedMap for that pixel
Well, as I know nothing about shader coding, I hope that someone could help me to code this shader, which will be probably very useful for many people.
Thanks in advance
PS: And for those who will ask "why don't you use deferred rendering ?", I will say "try to dvelop a video game, with IA, Navmesh,...And you will know why ;-)..TO SAVE FRAMES PER SECONDS !!!
Baking_00.doc
