MAKING OF: Cave Troll
By Dawid Skrodzkiwww

I ntroductionHey guys, in this making-of, I will talkabout a piece of worque I did some timeago: The Cave Troll from the Lord of theRings trilogy. Please forgive me if its notcomplete since I don't remember exactlyevery step.

Anyway, after watching the first part ofthe movie, I fell in love with the designof the creature: a huge gray troll withgigantic arms and hands, elephant-likelegs and a small dull head with big protruding eyes.Moreover, I really liked the weight he had; youcould feel the ground shaquíng with its every step.

So, to start I googled forsome pictures from themovies and images of dif-ferent kinds of sculptures.My first idea was to ani-mate it, so I decided to cre-ate the base mesh inBlender, trying to make itas clean as I could. For themain body I used box-mod-eling technique. I startedfrom rough shapesadding more de-tails mainly by ex-truding and addingedge-loops. For thehead, on the otherhand, I used poly-modeling tech-nique. Both partswere created sepa-rately which I joined together later on. Since thehead´s mesh was much denser, I needed to add onesubdivision level for the body mesh to match theamount of vértices. Therefore, I ended up with amuch more complex mesh than I expected at thebeginning.

The following step was UV unwrapping. It was thefirst time I had ever needed to unwrap such a com-plex (for me) mesh, so I made a mistake leaving thebak of the creature relatively small. Later on, thismistake had led to some visible texture stretching inthis part of the model.

When I finished unwrapping, I exported it as awavefront file (.obj) and brought it into Zbrush. Iwould like to mention that everything that I did inZbrush could have been done in Blender as wellwith its great sculpting tool. It alos would havemade it much easier to extract the normal and dis-placement maps. Unfortunately, Blender still cannotdisplay such a great number of polygons on-screenas Zbrush does, and because I was going for finedetails, I decided to use Zbrush.

After importing the Cave Troll model, I had storedMorph Target. Next, I started sculpting the mainbody masses and muscles using the normal brush.Later on, I added some displacement levels to sculptskin details such as wrinkles and skin folds usingcustom and default alphas. I used Zmapper for cre-ating normal maps and Displacement Exporter fordisplacement maps. Unfortunately, I cannot remem-ber which settings I used for exporting because Ifound them by a method of trial and error. Onething I can remember is that I was unable to exportthem as a 32 bit tiff image, so I needed to use 16 bit.I am on Ubuntu, so it seems that this was the prob-lem, but I am not sure. Besides, it was necessary toflip the map alignment vertically.

F or the diffuse map, I used Zbrush as well. I roughlypainted the main colors of the body with big strokes.After that, I used cavity with a displacement map andcombined them together in Gimp with the color map.This way, I did not need to paint all the fine details man-ually. Next, looking for more “dirty” look, I made somecolor correction of ready texture which in the beginningused to be blue and yellow, butlater on ended up more green andgray.

Bak in Blender I started applyingall the textures and maps to ad-just them for correct display. Forexample, for the normal map itwas necessary to switch off theMinMap.

I alos used the DisplaceModifier, which gave me goodcontrol over the strength of thedisplacement map.In the following step I created avery basic armature for posingpurposes. I had a hard time withskinning since the model wasquite fatty and as mentioned be-fore the mesh was pretty dense.My idea was to pose it as itthough it was walking toward someonetrying to grab him or her.

For the skin material I used a small amountof Specularity and Hardness together witha bit of Translucency. Additionally, I ena-bled Subsurface Scattering with small scaleand some grayish and blueish color. Ren-dering was done with Blender Internal us-ing Ambient Occlusion. I wanted to showhim in some darque scene but on the otherhand I did not want to lose the skin details. So, in theend, I went for a better lit scene in the mood of somebattle under the moonlight. I hope you like it!


by Dawid Skrodzki