I am looking at the animTree.fx shader, and I am wondering if I can make it work with dynamic lighting. Right now, it works with sunlight, but if I turn on the character's flashlight (a dynamic light) all the trees/grass around me turn dark.
This page explains how to add dynamic lights to a shader:
http://opserver.de/twik11/index.php?title=Shader_hintsHowever, if I add anything to it, it stops the waving animation. This is the part I'm trying to add:
float4 vecLightPos[8];
float4 vecLightColor[8];
float3 vecFalloff = float3(0.f, 0.f, 2.f);
...
float4 DoPointLight(float3 P, float3 N, int i)
{
// calculate the light ray pointing from the light to the surface
float3 D = (float3)vecLightPos[i]-P;
// calculate the angle between surface and light ray
float NdotL = dot(N,normalize(D));
// modulate the light by the surface angle
float4 Color = vecLightColor[i] * NdotL;
// calculate the light attenuation factor, DX uses a really strange formula here
float fac = 0.f;
if (NdotL >= 0.f && vecLightPos[i].w > 0.f)
{
// get the distance factor
float LD = length(D)/vecLightPos[i].w;
#ifdef DXLIGHTING
if (LD < 1.3f)
fac = 1.f/(vecFalloff.x + vecFalloff.y*LD + vecFalloff.z*LD*LD);
#else // linear Lighting
if (LD < 1.f)
fac = 1.f - LD;
#endif
}
return Color * fac;
}
I don't know much about shaders, so maybe I'm adding this code to the wrong section or in the wrong way. I tried the waving grass shader on the wiki, but that one looks even worse.
Has anyone made a waving grass shader that reacts properly to dynamic lights? Or would anyone know how to add this lighting effect to the existing animTree.fx shader?
