Mapping Textures 3ds max Mapping bitmap image files


Select that and then click Open and that image is loaded onto that bitmap node. And I’ve got Follow Current Selection enabled for my preview sample here and so whatever I select will be displayed there. Let’s double click on that bitmap node and in its parameters rename it call it base color. And then just connect its output to the base color map input on the physical material. Now the wood paneling material is currently assigned to the interior wall of the office here but as we saw in the last movie maps are not displayed in View Ports by default. To display a single map such as this base color select that map node and then go to the Material Editor Toolbar and enable Show Shaded Material in View Port. And the map node displays a red stripe indicating that it will be displayed in the View and now we can see some color over here on the wall but there’s discernible pattern like we see in the sample. The issue here is that there are currently no UV coordinates on the wall. Another way of saying that is that there are no instructions on how to apply that 2D bitmap onto this 3D surface. We’ll take a look at how to add UV coordinates in the following movie, but just to finish up the bitmap exercise let’s also create a Bump map.

The Bump map will create the illusion of small indentations in the surface that will make the rendering look more believable. I’ll duplicate this bitmap node here, hold down the Shift key and drag out to create a clone and then double click on that new clone to load its parameters and rename it Bump. And then in those bitmap parameters click on the big button which is labeled Bitmap and the Select Bitmap Image File dialogue appears again so that we can choose a disk file. But before we can do that there’s one kind of obscure but somewhat important thing we should do. At the bottom left of this dialogue is a section labeled Gamma. Gamma is the contrast curve of an image. Now this is a deep subject but I’ll try to make this brief. The way the physical material works is that it expects linear gamma. Another way of saying that is that the material expects all incoming maps to have a gamma of one point zero. Well eight bits per channel files such a PNG image generally have two point two gamma correction embedded in them to correspond to the way human perception works. High dynamic range files such as an EXR image generally have linear gamma to correspond to how CGI linear lighting works.

So this means that PNG files need to be corrected and a linear file such as EXR does not and the 3ds Max bitmap node tries to anticipate the gamma of the incoming file so that it is correct for the physical material. If Automatic Gamma is enabled, then for an eight bit file such as a PNG 3ds Max will apply an inverse gamma correction so that the final output of the bitmap node has a gamma of one point oh and that is exactly what we want for a color map such as the base color. But for any map parameter that is not a color such as Bump the file should generally be interpreted as linear data without any embedded gamma correction. So in this case we want to switch the gamma mode over here to Override with a default value of one point zero. And now the system will not over correct the file map and the detail on the Bump should show up correctly. Once we’ve chosen our Gamma option then we can choose the bitmap file. And here once again in Scene Assets Images we see wood_panels_thin_bump_2048x2048.png