Adding visual detail using a bump-map
If you want to "play along" with this example, load MonkeyCandle.lwo into Modeler You will also need these images: | |
MonkeyCandleTopTexture.tga | |
MonkeyCandleTopTexture.tga | |
Select the polygons that make up the Candelholder and the hand holding it. The easiest way to do this is in the Front or back view in Wireframe View, using the lasso (right click). Selecting polygons this way in Shaded View of Hidden Line only selects directly visible polygons, not the ones behind them. With SHIFT-A you can center the view on this selection |
Create a new UV map by activating the Map tab and choosing New UV map. Give the new texture cordinates a name at Texture Name Choose Map Type: Cylindrical - Axis: Y - Setings: Automatic. The automatic settings choose the Center and Size settings automatically to fit the selection The next step is to use this newly created texture space to stick an image on the surface which will be used as bumpmap. I will first apply it to the color channel in order to be able to see it in the Modeler's viewports and intercatively fine-tune the texture placement. |
In the Surface Editor (F5) select the Monkey material
In the color channel, add Image Texture layer In order to see what you are doing, switch the perspective view to Texture Wire mode. In one of the other viewports, choose UV-Texture as view, and next to the viewport selection, select the texture image you just applied. This will now appear in the backdrop of that viewport. |
Select Modify - Transform - Stretch by hitting h. In the UV-Texture viewport, scale the UV-map so the image nicely fits, and is repeated four times horizontally. When scaling the UV-map vertically, you see a copy of the image showing up at the bottom and top. We do not want the image to be repeated vertically. To fix this, goto the Surfafe Editor (F5) and in the texture for the color channel set the Height Tile to Reset To nicely fade the image out towards the top and the bottom, we have to apply a second image texture layer to the color channel |
Add a new image layer to the color channel and give it the same settings as the one already there, but load the MonkeyCandleTopTexture.tga image into this one. The other difference is that the Blending Mode is now set to Aplha. This will make the luminance value of the new image act as a mask for the image layer directly below it. This will fade out the top and bottom of the image. The image is now properly placed. However, I want to use it as a bump map, not an color map. on the left you see the object rendered with the image applied as a color map
In the Texture Editor for the color channel, on the top left choose Copy - Copy All Layers. By unchecking the boxes in front of the texture layer names, you can turn them off on the color channel Open the Texture Editor for the bump channel. On the top left choose Paste - replace All Layers. The image layers are now copied to the bump map. |
Bump maps do not show up until they are rendered, so we need to get our model into Layout (UV-Maps are always created in Modeler). Before we do that we want to save the model. Then, on the top right of the modeler, we can choose Send Object to Layout. When you render the object you will see that the bump is not quite strong enough. You have to push the bump channel up to 250% to get the result shown on the right |