k3d/share/shaders/k3d_texblender.sl:121:float BlendFloat(string mode; float K, newf, oldf)
k3d/share/shaders/k3d_texblender.sl:125: if (mode=="m") res=(res+K*newf)/(1+K);
k3d/share/shaders/k3d_texblender.sl:126: if (mode=="f") res*= ((1-K)+K*newf);
