3D for Zappar

Coordinate system

Zappar's coordinate system is based on the center of the scene being the center of the target image.

The top of the image is Y = 1 and the bottom is Y = -1. The X coordinates of the left and right sides of the image will then naturally depend on the aspect ratio of the target image, and can extend as far or as little as required by the size and shape of the target.

The Z axis points up, out of the image.In other words, the target image should be placed on a plane in Maya/3DMax, centered at the origin and scaled so that the top is at Y=1 & the bottom is at Y=-1.

(Images Above: Center of the target image)

Any objects & animations built using this background plane as reference can then be exported and placed directly into Zappar without any further positioning or scaling.

Textures

Textures need to sized at ^2 sizes – 16, 32, 64, 128, 256 px etc.

Textures sizes 256 x 256, 512 x 512, 1024 x 1024. Textures don't have to be square however – e.g. 512 x 256 or 128 x 1024would be allowable.

Zappar will not recognise procedural textures from Maya/3D Max, All shaders must be linked to image files.

(Note that Zappar also does not accept or create any dynamic lighting or shading, so all lighting & Metals should be baked into the texture. e.g Diffuse map, OC map, Normal map & Spec Map.)

Zappar supports Only 1 set of UV coordinates per vertex, It also only supports 1 texture per mesh.

(Images Above: Left side Correct UV layout for zappar, Right side Incorrect UV layout)

If you have multiple submeshes with different textures the POD exporter will split these into separate meshes which will be rendered separately in Zappar. Although this will look correct it should be avoided for optimal performance.

Use .jpgs for solid images and .pngs for any images using alpha.( Note Try not to use to much alpha Maps on one scene this will slow down performance)

(Images Above: Example of a baked texture map & Alpha Maps)

Rigging

Skeleton rigs for Zappar need to have a maximum of 3 influences per vertex.

Also ensure that bones extend to all extremities of the skin(e.g. fingers should finish with a joint at the fingertips and not at the last knuckle).

(Images Above: Example of Rig)

The number of bones is one of the most important factors for performance, so try to keep this as low as possible.

(Images Above: Example of Full Body Rigg)

Zappar does not support Blend shaps (faces ect need to be rigged with bones) Driven keys support on Zappar & Also help to speed up Animations times for face rigg.

Before skinning, Delete all history & None Deforme-type-history on the skin mesh & freeze transformations (If not, the animation of the skin may be lost during export)

(Images Above: Example of wait map issuse)

Also, problems occur with large numbers of skin clusters. So, if you have many separate meshes, do not combine them all into one object. It's best to skin them separately, or at least ensure you don't have large numbers of meshes combined.

Animation

Animations Can be built at 20 FPS, 24 FPS & 25 FPS.

When animating skinned meshes the first frame of the animation should be set to the bind pose of the rig for the animation to look correct in Zappar.

At the scene side it is possible for Zappar to only display a subset of the animation to the user, so the bind pose will not be displayed to the user unless required.

Zappar will accept :

Scaling keys Motion parthsTranslation keysRotation keysGroup node animation keysParent/Child relationshipsConstraints (e.g. the forearm planes in the guitar animation are point-constrained to the hand planes)

Zappar does not currently accept:

Visibility keys:If required, plane opacity can be controlled and faded by code at the build stage (e.g. the hands in the guitar anim fade in and out as they appear and disappear from the scene).

(Images Above: Alpha 3D Rigg & Animation)

Alternatively, sudden appearance of planes can be effectively faked by translating planes from far outside the viewable area to within the space of the target image across a single frame.Vertex animationUV animationSplinesBlend shapes

If using images with alpha, make sure the objects closest to the camera in 3D space are also above the lower objects in the scene list/outliner. This ensures Zappar will draw these first and avoid any unwanted alpha overlay artefacts.

Exporting

Zappar currently requires animations to be exported as .pod files. You will need the PVRGeoPOD plugin to export .pod files.

The plugin for Maya/3DSMax can be downloaded from:http://www.imgtec.com/powervr/insider/powervr-pvrgeopod.asp

(Registration required).

Read the Documentation that comes with this plug-in to install it to your 3D application.

Once this is installed, follow these steps to export:

Select all the objects for export and select File>Export Selection (don't include the background reference plane or any other reference props)

Note that many or all objects from a scene can be included in a single .pod file – individual .pods for each object are not required unless the objects are moving or reacting independently of the main animation.

In file type, select POWERVR Exporter and click Apply.

(Images Above: Maya Export Selection)

Enter the name of the pod file including the .pod extension (this is not automatically generated).

Locate the .pod file in the same folder as your 512x512 JPG textures when you load the pod file, it sources textures from the same folder

In the export options box, the default options should be fine. Make sure Export Skin Modifiers is ticked. Hit Apply to start the export.

(Images Above: Stranded export settings)

Exsporting animations: In transformations only select Exsport animations.( this option will export your animations with out adding intertwines frames)

(Images Above: Stranded Animation export settings)

If select Index animation data & exsport transformations as matrices.( this option will add Frames to your animations)

Testing

Pod file viewer is available from:

http://www.imgtec.com/powervr/insider/powervr-pvrshaman.asp

This can be used to check your pods before submitting them.

(Images Above: PVRShaman viewer)

Unfortunately the previewer applies default shading to the scene which will not appear in Zappar builds however the geometry, animations and texture files can all be checked for errors.

This stage is also useful for checking if unwanted pieces of geometry have been accidentally included in the .pod (e.g. the reference background plane).