by nishanth raj on May 6, 2011 at 2:36:24 pm
i want to show a iron rod coming out of a induction heating machine. my problem is i want to show the iron rod's one side (which is just coming out from the induction heater) almost yellow. the other side of the rod is getting cooled slowly therefore this side should be darker (like a normal iron rod). and this iron rod is continuously coming out of the machine.
like setting different texture in Pflow using age test.
i don't know how to explain that. :)
i need one side very bright and glowing yellow / orange and the second side should be textured with a bitmap.
The way I would do it would be to output two different versions of the same iron rod - one completely cool (black), and one completely hot (red).
It would then be a simple matter to bring it into After Effects (or any compositing software) and, using a feathered mask, control the exact timing of the cooling. In this way, if the client wants a slightly different timing on it, for example they want it to look exactly the way it looks in reality, you can shift your mask.
While a gradient map should work, I think that shifting it along the length of the rod to show the cooling process could be much more difficult than the above process. Good luck!
Re: gradient texturing by Tiago Ribeiro on May 7, 2011 at 2:14:44 pm
I guess that you need to blend between three settings:
1) the rod is cold (and black)
2) transition to hot (rod gets red)
3) rod is hot (that yellowish texture)
if you just blend between the texture and the black rod, you won't get any red in the transition zone
i'll give you two solutions. both the mix and composite maps can be found in Maps/Standard in the Material/Map browser.
you can do this using a "Mix" map in your diffuse slot.
In this material you have two slot (material 1 and material 2), and then another slot for the mask. If you put a gradient map in the mask slot, then your materials will get blended using that gradient.
you can then even animate the gradient so that you have your desired effect
of course, to blend three materials, what i would do would be to use one mix between hot and transition, mixing with the cold rod material
hierarchically it should be something like this: #Mix
-Mask: Cold-to-hot gradient
-Material1: Cold Rod material
-Mask: Red-to-hot-texture gradient
-Material1: Red Transition material
-Material2: Yellowish really hot material
you can also use a composite map to yous diffuse slot.
in this map you get slots that act as layers, and each layer has its own alpha mask, and blend mode, so that you can control the way they sum up
do whatever you feel more comfortable with, search for some tutorials on the Mix and Composite maps, so you'll understand how they work
Re: gradient texturing by nishanth raj on May 9, 2011 at 6:49:42 am
thanks Joseph W. Bourke & Tiago Ribeiro. i almost got it.
in fact, i have the texture. but the problem is at start iron rod must be completely yellowish (through out iron rod). until two to three meter it should remain completely yellow. because the coolant will be applied only after one to two meters. after that it should become normal iron textured gradually.
now my problem is how to set a time for this change.
I believe you have two options - animate the material by applying keyframes to the actual textures, or, as I described in the earlier answer, create two versions and transition them in After Effects, or another compositing program.
Another thought. If your texture map is a gradient map, I believe you can animate the points where the gradient transitions, and that might do the trick.