bhaveshpandey Posted February 14, 2009 Share Posted February 14, 2009 hi..i'm working on a scene where there's a few things falling into a pretty bug hole in the street.. i'm past the basic setup and now am struggling with shading and textures for the same.. since i have only covered little portion of the road with the cg plane, i have now mix the textures and materials such that they mix... i want to sort of mix the shadow which is extracted by Shadow matte material and a texture i have put up on the road. i tried implementing this with VEX, but could not figure out how i could make shadow matte sort of material in vex.. looking out for some help Quote Link to comment Share on other sites More sharing options...
stevenong Posted February 14, 2009 Share Posted February 14, 2009 Usually, the way I use the shadow matte is as a matte channel for a Colour Correct COP to darken the element or plate. I haven't seen this tutorial but maybe it will help. Hope the above helps! Cheers! steven Quote Link to comment Share on other sites More sharing options...
bhaveshpandey Posted February 15, 2009 Author Share Posted February 15, 2009 hey Steven, the link is more for basically setting up an environment and a bit of PBR.. i need a way to mix a shadow matte material and another material (for eg. something like VEX layered material) through VEX. had these (shadow matte and VEX layed materials) been available at VEX level i could simply plug those to a color mix node and control the mixing of each material.. the issue is these arent available at VEX context, so i gotta figure out how to sort of roughly set each of these 2 materials in VEX. (which for me is pretty daunting as a beginner..but i do know its gonna be a great learning experience thiugh) if lets say we were to set up a shadow matte material in VEX which wont be a lot CPU intensive i.e like it would probably follow depth mapped shadows rather than raytracing (although even raytrace would do for now, atleast i'll understand something out of it ) , then how would we go about it?? thanks again hoping to get some way around this cheers Quote Link to comment Share on other sites More sharing options...
bhaveshpandey Posted February 17, 2009 Author Share Posted February 17, 2009 i found a node named shadow matte in vex.. since i did not know about the usage i checked out the help docs for the same.. but i'm still as clueless as i was before, so as to how to use this in VEX context to extract a shadow matte.. could anyone please shed more light on the usage of the shadow matte node in vex.. (it also mentioned something about illumination loop..i'm really lost now. could someone also tell me more about this please) thanks a ton Quote Link to comment Share on other sites More sharing options...
bhaveshpandey Posted February 18, 2009 Author Share Posted February 18, 2009 (edited) i have had bit of a luck trying to sort out the issues.. i'm almost there..BUT not quite here's a screen grab of the simple VEX network i have put up..its still incomplete and i want to know if i have missed out on something.. http://www.flickr.com/photos/27793702@N02/3290733086/ now i need to figure out how to plugin an image as a mask in the matte node in VEX shop context.. PS: please excuse the fact that i could not post the pic, instead i have posted a link ( could not figure out how to post the pic tried putting up from my flickr account but its not accepting it Edited February 18, 2009 by bhaveshpandey Quote Link to comment Share on other sites More sharing options...
bhaveshpandey Posted February 23, 2009 Author Share Posted February 23, 2009 hey stuck real bad in a situation i finally managed to put together a shader which i was looking out for, but when I render the frame, there's no shadow on the ground what i believe is that the shadow is being matted out because when you see the alpha of the rendered output, there's not even a slightest indication of the objects' shadow on the ground here's an image. (if you cant see the image pls follow this link: http://4.bp.blogspot.com/_VHjD5bX033E/SaLo...noShadAlpha.jpg ) i tried a few things in the VEX network but its not happening (at least for now) I have attached the scene which has the setup for the shader. could anyone please check it out and point me to the right direction regards, crater.rar Quote Link to comment Share on other sites More sharing options...
storyteller Posted February 24, 2009 Share Posted February 24, 2009 (edited) I'm not sure if I got your problem but just look into your shader. I used a ShadowMatte and added it's results to the alpha and opacity values. Now there is a shadow and a proper alpha mask for it. Hope that helps. But why don't you use a separate shadow render pass. It would be more easy to tweak the shadows in the composite step. It would be nice if you could use $HIP/filename.ext instead of absolute path names Chris crater2.rar Edited February 24, 2009 by storyteller Quote Link to comment Share on other sites More sharing options...
bhaveshpandey Posted February 24, 2009 Author Share Posted February 24, 2009 thanks a lot for the reply Chris.. I'm gonna look up the test results and update you on this. PS: what you say makes sense. i tried setting up an Occlusion pass using light template but, it dint work too well..dint really try a shadow pass alone. all this mess makes suffer from Amnesia thanks again Quote Link to comment Share on other sites More sharing options...
storyteller Posted February 24, 2009 Share Posted February 24, 2009 There is a very good paper on render passes: http://www.sidefx.com/index.php?option=com...&Itemid=263 Chris Quote Link to comment Share on other sites More sharing options...
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