k3d/share/shaders/k3d_contacshadow.sl:25:    textureinfo(shadowname, "viewingmatrix", matNl);  
k3d/share/shaders/k3d_contacshadow.sl:30:    textureinfo(shadowname, "projectionmatrix", matNP);  
k3d/share/shaders/k3d_fresnelplastic.sl:19:#define CHKTX(tx) ((tx != "" && textureinfo (tx, "exists", 0) != 0)? 1: 0)
k3d/share/shaders/k3d_softboxes.sl:138:	    textureinfo(boxTexture,"channels",nChans);
