minning.de - Stefan Minning: CG Artist and Developer

With the char­ac­ters and story roughly laid out in our minds and on paper, our next step towards the real­iza­tion of this project was cre­at­ing sto­ry­boards. You might say we “cheated” a bit in this phase, as we did not actu­ally draw most of the sto­ry­board sheets at all — instead, since we hap­pened to already have some early mod­els of the char­ac­ters and envi­ron­ments under­way, we used these to cre­ate mock sto­ry­boards in 3D. This of course ben­e­fited us immensely, as we are def­i­nitely bet­ter 3D artists than drafts­men and this way had more options and patience for exper­i­ment­ing with the scenes’ lay­outs and get­ting per­spec­tives to work just right. Fur­ther­more we could keep work­ing in these ini­tial scenes over the course of the project and con­tin­u­ously updated them to include our lat­est improve­ments in mod­el­ing, tex­tur­ing and ani­ma­tion. This work­flow stream­lined our task of man­ag­ing the huge num­ber of dig­i­tal assets a 3D film pro­duc­tion invari­ably entails.

3D char­ac­ter model

The char­ac­ter mod­els in this film con­sist of very basic meshes with a poly­gon count closer to last gen­er­a­tion video games than most mod­ern film pro­duc­tions. We opted for this route because it is well suited for our sim­ple char­ac­ter designs. Their bold fea­tures helped us to focus on cre­at­ing strong sil­hou­ettes that are eas­ily read and not hav­ing to worry so much about get­ting the rig messed up or fac­ing other tech­ni­cal annoyances.

The rig itself is quite ele­men­tary and based on one we had cre­ated for an ear­lier ani­mated short film, Now That Takes The Bis­cuit, which was sim­i­lar in style to this film. There­fore the rig lends itself well to car­toony ani­ma­tion and fea­tures sup­port for stretchy limbs and basic squash and stretch effects but does not offer much in the way of fancy automa­tion or dynam­ics.

Clara’s facial fea­tures where ren­dered in 2D

While Belze’s face was rigged the tra­di­tional way using blend shapes, we decided for a totally dif­fer­ent approach for Clara; her flat and car­toony expres­sions would have been imprac­ti­cal to model, tex­ture and ani­mate in 3D, so we devel­oped a pro­pri­etary plug-​​in for Adobe After Effects that projects the facial fea­tures onto her face in 2D. For this to work we needed to ren­der out UV– and ID-​​passes of her head so that our plug-​​in would know where to place the eyes, mouth and nose. As these facial fea­tures were hand-​​drawn and ani­mated in 2D, it was easy for us to cre­ate cus­tom expres­sions depend­ing on each scene’s spe­cific needs and to time and ani­mate them accordingly.

At one point dur­ing the pro­duc­tion we were con­sid­er­ing using motion cap­ture tech­nol­ogy for our char­ac­ter ani­ma­tion but even­tu­ally came to the con­clu­sion that it would be cost-​​prohibitive and would also most likely work against the car­toon look we had estab­lished for this film.
So every­thing ended up being ani­mated by hand the tra­di­tional 3D way. The biggest chal­lenge here was in prop­erly emu­lat­ing the car­toon ani­ma­tion style we had used as our ref­er­ence. We soon learned that the way squash and stretch ani­ma­tion works in 2D may look great but is unfor­tu­nately phys­i­cally inac­cu­rate and there­fore hard to trans­late into our metic­u­lous world of three-​​dimensional space and move­ment.
Our solu­tion was to ani­mate as far as pos­si­ble in 3D and to after­wards empha­size the ani­ma­tion and squash and stretch effects using 2D tools such as the liquify fil­ter in Pho­to­shop on a frame-​​by-​​frame basis.

All char­ac­ters were shaded and lit using our 2D in-​​house tool Normality

This method became fea­si­ble only due to our par­tic­u­lar approach to shad­ing and light­ing. Unlike most pro­duc­tions where shad­ing and light­ing are applied in a 3D appli­ca­tion on actual 3D mod­els, we used an in-​​house solu­tion to avoid this often frus­trat­ing and painstak­ing task. In this project the shad­ing and light­ing was done in 2D in Adobe After Effects using our pro­pri­etary plug-​​ins Nor­mal­ity and Celu­light. This real-​​time re-​​lighting solu­tion enables us to inter­ac­tively shade and light on ani­ma­tion sequences that were ren­dered as normal-​​passes from a 3D pro­gram before­hand.
We found sev­eral advan­tages in this method: All changes are applied in real-​​time mak­ing the process feel far more intu­itive and cre­ative than hit­ting “re-​​render” time and time again in a 3D pro­gram. As there is no appre­cia­ble delay involved this work­flow lends itself well to cre­ative exper­i­men­ta­tion. And best of all, we could view the char­ac­ter ani­ma­tions within the con­text of the final back­grounds in a color-​​corrected, com­pos­ited envi­ron­ment, mak­ing it easy to judge the qual­ity and appear­ance of our final shots.

Nor­mal­ity offers a vast array of tools and controls

To use Nor­mal­ity a num­ber of sim­ple passes are extracted from a 3D ren­derer which con­tain for exam­ple infor­ma­tion about an object’s sur­face nor­mals and the scene depth encoded in a 2D image for­mat. These passes ren­der in mere sec­onds and require no tweak­ing, mak­ing it a totally fail-​​safe process.
This image sequence is then imported into After Effects, where Nor­mal­ity is applied to the nor­mal pass. Once a light is added to the scene, Nor­mal­ity cal­cu­lates the shad­ing right there in the com­posit­ing envi­ron­ment; any changes to the lights and shaders are made vis­i­ble imme­di­ately and interactively.