..::mpv cellshade::..

Note from the author: This article was written with 3ds max 5 in mind. Due to software improvements, bug fixes, user interface amendments and added features, some items listed below may not apply to 3ds max after version 5 (note: 3ds max 6's Mental Ray Contours shader should be used instead of Ink 'n' Paint's Inking feature as it yields much better results!!)

With the majority of cartoons now integrating some kind of CG work in their pipeline, just how easy is it to turn 3D to 2D, and does it actually look any good?

Recently, there has been an increase in the amount of 3D media integrated within 2D media mainly in the film industry, going back as far as Beauty and the Beast and as recent as Treasure Planet. Nowadays it doesn’t just have to be film production that benefits from this technology. Design, print and commercial media are now actively using the same methods within 3D software to streamline tasks normally painstakingly undertaken by the 2D artist.

Now included within 3ds max 5 is a material that allows us to shade our objects to make them appear as if they were a 2-dimensional image. Just by utilising it’s basic settings, this “Ink ‘n Paint” material creates effective results, but with it’s array of features and ability to be modified it opens the doors for styles beyond those defaults. Here we will model out a conceptual vehicle for a print advertisement with this new material in mind to get the best from it’s features and avoid it’s limitations…

Should you wish to jump right to the materials and not bother with the model creation, a library of the materials created in this tutorial and small sample scene is included at the bottom of this tutorial.

	Create a box primitive 150x200x300 with 3 length and width segments and 5 Height segments. Right-click the object and collapse to an Editable Poly. Amend the vertex positions to those illustrated and weld the top corner vertices to those below them to create a diagonal edge as illustrated. Also, weld the vertices at the bottom left hand side to create the geometry illustrated.
	Select the bottom inner 3 polygons as illustrated and extrude down twice. Amend the vertex positions in the left viewport as before and weld the vertices on the right hand side of the new extrusion to form a point as shown.
	Select the large front polys and Inset them slightly. Next, extrude backwards to create the windscreen. Perform the same task at the rear, but extrude back more to create a space for an additional object. Extrude back the bottom polygons as show to create additional indentations.
	Extrude out and amend the vertex positions at the bottom of the model to create a curved surface. At the rear, of the model, slice across the middle polygon underneath the new inset and at the rear of the curved surface. Target weld the bottom inset to create a chiselled inset, select the rear 3 polys and extrude by a very slight amount. Pull these new polys outwards..
	Select the new extrude’s vertices and negative scale along the x-axis (using the Selection Center tool) to line them up vertically. Extrude again and pull the top in to create a slight slant. Select the middle end polygons, inset and extrude back as before. Remove any 5-sided (or more) polygons by creating new edges and turning them into 3 and 4 sided polys.
	Inset, extrude and target weld to create a small box sitting on the real extrusion of the model. On the top of the model, select the middle rear 3 polys and extrude up and shape them as shown. Select the middle poly on the front slant and inset, extrude and target weld to create the outset polys. Select the new front poly and inset and extrude back several times to create the indentations.
	Down along one side of the model, select the corner edges around the model (top, front, side and rear) and chamfer them a little to generate the illustrated result. Center the object’s pivot, add a symmetry modifier and set it so the chamfered side of the object is mirrored on the other side.
	Select the two large polygons on the side of the model and inset them a little. Tesselate the inset polys a few times. Target weld the excess vertices to just end up with horizontal polygon rows. Bevel out each polygon row individually to create the desired result.
	As with the sides of the model, select the harsh edges around the top and side of the rear extrusion and chamfer them a little to smooth them out. Target weld and create edges to clean up any 5+ sided geometry and to ensure there aren’t any overlapping polys.
	Collapse the geometry down to an editable poly. Bring in the sides of the curved surface at the bottom of the mesh. Select the windscreen and outer polys as shown and slice them. Target weld the floating vertex next to the new slats to the base of the top slat. Select the inner polygons created by the slice and extrude back a little as shown.
	Select any harsh right-angled edges created by the last extrusion operation and chamfer them slightly. Select the rear corner polygons and inset, extrude back, inset again, extrude out, and chamfer the edges of the outward extrusion. Inset and extrude the rear-facing outwards extrusion as shown.
	Select the top line of polygons running the length of the model, inset and pull the inset polys up. Inset slightly and extrude back down. Target weld the corner vertices to fan out the inset at the front and rear of the roof to form a channel as shown.
	Select the large polys underneath the extruded slats on the side of the model, inset slightly and extrude inwards. Target weld the inner front and rear vertices to the outer front and rear vertices to create an “intake” as shown. Select the top side chamfer, inset and extrude back as illustrated.
	Finish off the roof by target welding the roof extrusion to the front of the roof to create an incline. Also, chamfer any harsh edges around the top of the headlight housing.
	On the bottom end of the rear extrusion, extrude down and across to create a mudflap. Underneath the extrusion, extrude out about 7 times and reposition vertices and weld to form an arm to hold the rear wheel. Insert vertices in the middle of edges in edge sub-object mode and create additional edges using these vertices to extrude the resulting polygons out to create a fin at the rear.
	Create a box 240x240x110 with 3 Length 1 Width and 4 Height segments and position as shown. Collapse to an editable poly. Adjust the vertices in the left viewport to represent those in the screenshot.
	Chamfer the right-angled edges of the mesh and re-form the vertices so the mesh’s sides bulge out as in the screenshot’s front viewport. Select the front and back polys of the mesh, inset and extrude back. Select the large polygons on the side and top, inset, extrude back, inset again, extrude outwards and outline a little to taper the extrusion.
	Create a cylinder with 30 radius, 30 height, 3 height segments and 18 sides. Collapse to an editable poly and position as shown. Extrude the middle polygons back to form an axel. Inset the cap ends to form a rim and extrude back. Extrude outwards again and outline, repeating to form a slight curve. Finally extrude back, inset then extrude outwards again to create an indentation in the centre.
	The front and rear suspension and the rear ventilation geometry was created from a single box with several length iterations. After collapsing to an editable poly, each row of iterations were bevelled independently. The geometry was then repositioned, scaled, tapered and sliced (for the ventilation) and amended to fit it’s place.
	Create a cylinder, radius 50, height 23, 4 height and cap segments and 18 sides. Clone this cylinder and hide it. Scale inwards the outer ring of vertices to curve the outer surface. On both sides, create the outline of the inside of the wheel using new edges, extrude back, delete the unwanted polygons and weld the two inner sides together. Chamfer edges to remove any harsh right-angles.
	Unhide the cylinder and use the primitive’s slice feature to remove the bottom part of the cylinder as shown. Increase it’s radius and height a little so it fits snugly over the wheel. Inset and extrude the underside of the wheelarch for the wheel to disappear into. Also, extrude the front few polygons, inset them and extrude to form a headlight and add any additional detail to the sides of the wheel arch as desired.
	Finish off by refining the geometry further if desired. I’ve created a slight wheel arch for the large front wheel’s axle (a modified cylinder) to enter, and have also created headlights between the wheels and underneath the windscreen, using inset and extrusion techniques as before.
	Create a new Ink ‘n Paint material and label it “Paint Light”. In the material’s Basic Material Extensions rollout, check off 2-Sided (as none of our objects have holes or backfacing polygons). Set the Paint Levels to 4, the Shaded spinner to 50 and check on Highlight
	Set the Lighted colour swatch to RGB 190,220,220. Drag this swatch to the Highlight swatch and copy it. Amend it’s saturation so it’s nearly white. In the Ink controls rollout, set the Ink Quality to 2 and set the Outline, Overlap and Mat ID swatches to white. Check off SmGroup. Assign this material to the wheel arch, main body and solar cell geometry.
	Copy this material and label it “Headlights”. Set the Paint Levels to 2, Lighted swatch to RGB 254,232,133 , shaded spinner to 80 and Highlight to white. Check on SmGroup and set the swatch to white. Clone this material another couple of times labelling them “Rear Lights” and “Glass” and set their Lighted swatches to RGB 177,0,0 and 210,210,255 respectfully.
	Copy the Paint Light material and label it “Suspension”. Amend the Lighted swatch to RGB 238,198,0 and the Highlight swatch to RGB 247,226,131. Set the Shaded spinner to 70 and Glossiness to 20 to create a wider highlight to indicate a matte finish.
	Copy the Suspension material and label it “Ventilation”. Set the Lighted swatch to a mid-grey and it’s highlight to white. Set the glossiness to 50 to indicate a shiny surface. Now you’ve got the knack of how the basics of this material setup works…
	…repeat this material copying procedure and set up the following materials: Tyre Rubber, Rubber (same, but darker), Tyre Metal (gold metal), Tyre Chrome (same but grey colour), Mech Metal (less shiny and slightly darker grey), Paint Dark (as Paint Light but, er, darker!), Solar Cells (shiny blue), and Gold.
	If you don’t want to set up all the materials, load in the ca_cellshade.mat 3ds max material library included on the cover cd. By selecting polygons on our model, we can assign materials to these polygons. As we’ve already assigned the main material to the mesh, all we now need to do is add the detail materials.
	Select the relevant polygons (not using move or rotate incase you translate the polygons by accident) and assign the materials to those as illustrated. The most convenient way to assign materials around indentations (such as the headlights) is to select the headlight polygons, expand the selection, assign the outer material, contact back and assign the other material. Easier than selecting every polygon!
	We can now refine the geometry by adding a Meshsmooth modifier to the wheel and wheel arches and set it’s Surface Parameters to Separate by Materials. This will ensure the materials boundaries will remain intact once the geometry is refined. Instance clone and mirror the front wheel setup to the other side of the vehicle. The same smoothing setup should also be assigned to the single rear wheel.
	Finish off the scene by placing the vehicle in situ. The illo to accompany this tutorial was rendered out in max with one target light to generate shadows and a gradient map set to the environment slot to create the sky. The ground was a single plane with various polygon extrusions to create an interesting an irregular surface pattern.
	Download the cellshade material library

..::additional tips::..

Quality Vs Speed: Even though the solid paint colour renders out quite quickly, even for print-resolution jobs, Ink ‘n Paint’s inking lets it down considerably in matters of speed and quality. In fact, if you are producing a print resolution image, it would be advisable to ditch the inking altogether and simply use the paint shading.

Alternative solutions: As an alternative to Ink ‘n Paint’s slow inking, try using some of the excellent third party renderers out there. Illustrate!, Plasma (whose renderer embeds into 3ds max after installation) and Vectra3D are faster and give better results.

How did we create the illustration? (see gallery section): The illustration to accompany this tutorial was rendered using Plasma’s vector renderer directly from within 3ds max. The render was then trimmed to remove any non-essential information then brought into Photoshop where it was simply colour corrected and had the overlaid text added.

Benefits of Ink ‘n Paint: Due to the fine inking line of the Plasma render hardly being noticeable in this print res image, rendering out using Ink ‘n Paint would generate an almost identical result if it’s inking feature was turned off for every material. Due to it being material and not renderer based, Ink ‘n Paint materials can be utilised in scenes that contain “normal” material setups, creating an interesting mixture of styles. As this material contains many map slots, a great variation of material effects and styles can be created. For example, create a pencil sketch effect by dropping in a screen mapped scan of pencil shading or create nice gradual effects by adding a gradient into the Lighted map slot. Also, interesting inking effects can be designed by dropping maps such as Noise into it’s Ink Width map slot. The sky is the limit!

Initially published: Computer Arts magazine, Issue 82, April 2003.

Copyright © Pete Draper, April 2003. Reproduction without permission prohibited.

www.xenomorphic.co.uk