Creating a Demigod

Creating a Demigod: Vampire Lord Erebus

character pipeline document by Matt Dudley

(note: this document was translated and published in Russian in PC Games RU magazine)

The Demigod characters are at the core of the game. The characters all had initial designs created during preproduction.

Common themes established during pre production include: future fantasy (mechanical technology infused with magic, etc.) An epic scale for environments and characters. Environments were to be ancient arenas passed on between civilizations that came and went.

Concept/Visual Design:

The Vampire Lord Erebus design is centered on the idea of a custom suit that recycles and circulates blood to his body.

Image#1 Early concept art by Nate Simpson:

Earlier designs of the Vampire Lord had the character’s proportions much more like a wrestler or football player. In order to add more variety to the look of each character it was decided to exaggerate the proportions toward a thinner silhouette.

The existing design was to be left intact but the proportions were stretched out and exaggerated. Ex: his arms and fingers elongated to give him a more creepy and sinister appearance and his features softened to give him a more androgynous/mysterious vampire look.

Image#2 Orthogonal drawings with revised proportions by Steve Snoey:

Action sketches were done to explore the character’s attitude.

Some show him cackling in the heat of battle as he uses his powers, etc.

Image#3 Action sketches by Steve Snoey:

As the design evolved it was decided that the Vampire Lord should still maintain regality and elegance as a gentleman of substance, even in battle.

The design goal for these changes was for players to be able to tell the difference between the Vampire Lord and Regulus (another hero of similar stature and height) at a glance just from their silhouettes.

Modeling:

The character models for Demigod were planned from the beginning to be highly detailed so as to look cool in game and be useful in marketing pieces and pre rendered movies.

After concept art is approved, orthogonal drawings are made as reference to model from. (see Image#2 orthogonal drawings above.)

This is an important step as it helps to reinforce the design of the silhouette. This also provides another pass at refining and resolving details that may work in the original concept but are problematic in 3d.

Models were created in stages/passes. 1^st pass is very rough with a focus on volume, silhouette and proportions.

Image#4 1^st pass rough model, based on an early version of the concept:

Image#5 Rough geometry with revised proportions:

After the first pass model is complete it is sent to animation for rough rigging and animating.

This is more efficient as animation can begin and the animators can give informed feedback towards the final model.

Animations are focused around having strong easy to read silhouettes for each given movement. With this approach it is easy to block in animations around key poses or moments of a given action. By focusing the animations and the model around the concept of the silhouette it is easier to imagine how to improve both as the work progresses.

The rough character is exported to the game and any changes to proportion for animation or readability in game can be decided on before the final model is completed. (See Image#5 above, this model was sent to animation for export to the game.)

Image#6 Work in progress toward the final model:

For the final geometry there was an emphasis on building enough detail so as to make the model easier to work with in Zbrush.

For example a focus on quad polygons and topology flow, that are less efficient for display in the game, but much more efficient to work with in Zbrush.

Because the Demigod engine has great support for level of detail swapping of models this makes the high detail/high quality approach possible. (See Image#6 above, the face has more detail than appropriate for in game.)

Once the high detail model is complete it can be used in many ways, while a more efficient level of detail model is generated quickly using poly reduction tools in Softimage XSI for better performance in game.

Image#7 Final model:

After the final geometry is complete, UV’s are created. A standalone program called UVlayout is used for this. Even though it is another piece of software; its efficiency is worth the effort up front.

Image#8 Final UV’s created with UVlayout:

UV’s are created to fit one texture per model. This is more efficient for rendering in the Demigod engine. UV pieces/shells are organized to be easier to work with when texturing and editing the normal maps generated by Zbrush.

(see Image#8 UV shells are oriented vertically. Limbs and other symmetrical elements are mirrored in cases where the UV seams will be less obvious. This is easier to work with when editing a normal map.)

Once UV’s are completed the model is exported to Zbrush for sculpting details and generating the normal map.

Image#9 Work in progress in Zbrush:

Texturing:

The normal map is the first texture created. It serves as the basis for the rest of the textures applied to the model.

Image#10 Normal map generated from Zbrush:

After the normal map is generated, the diffuse color map work begins.

The diffuse color map is created in photoshop.

First step: an ambient occlusion texture is generated. (There are many different tools for this, for Demigod a standalone program called FAOgen is used for speed and ease of use.)

Image#11 Ambient Occlusion texture generated from FAOgen:

The ambient occlusion texture is useful as a starting point but it only shows low frequency detail.

For finer high frequency detail a useful trick is copy the blue channel from the normal map texture in Photoshop. Apply it as a multiply layer for referencing finer details when painting the diffuse color map.

Image#12 blue channel of normal map:

A typical diffuse color map has relatively simple colors that are each saved on separate layers in Photoshop. (This makes it easier to refine and change the colors as needed.)

In many areas the colors are applied very quickly and the ambient occlusion and blue channel layers are used as unifying elements.

As the normal map is the main source of texture detail, better results come from a simpler diffuse color map that reinforces details found in the normal map.

Image#13 Final Diffuse color map:

The final texture created for a Demigod will be referred to as the SpecTeam texture.

This texture is composed of four individual grayscale textures that are stored in each channel of a 32bit color texture. Each channel is used as a mask related to four specific rendering attributes.

Ex: Red Green Blue Alpha. The Red channel contains a mask that controls the amount of reflectivity (environment map reflection). The Green channel is a mask that controls the amount of specularity (shiny highlights). The Blue channel masks the amount/intensity of glow that is applied at render time. The Alpha channel masks the amount of player/team color that is displayed on the Character.

Image#14 Mask textures stored in each channel of the SpecTeam texture:

Shaders and Rendering in game:

Rendering Demigods involves using shaders. Shaders define how the various textures are used in order to render the character and other elements in game.

Image#17 WIP sequence of images showing how various textures are used when rendering a Demigod:

Image#18 Vampire Lord Erebus rendered in Demigod engine: