URCHN Arkipelago Maya to Blender

Maya to Blender

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First Steps

Because Blender just went to a radical new version, a lot of the docs are out of date, here's some hints

  • Go to Blender.org and download blender for your platform
  • Click here for the in progress 2.5 wiki manual.
  • CgCookie has great video tutorials, mostly introductory, mostly free.
  • 4th Edition of the Blender Basics book a highschool? level book, but looks like it has some nice intro stuff in it. And it's free! (to download)
  • Blender for Dummies 2nd Edition is 2.5 based.
  • Download a nice rig ( I reccommend Gilgamesh, or RedNelb from PepeLand ) and play!

Blender Mental Model

Data

If you think of Maya Data at it's basis, as a bunch of nodes living in a scenegraph, Blender Data will make sense in moment: Blender data at its basis is a bunch of datablocks/DNA. These are much more course grained (i.e. 'big') than Maya nodes, and they have types: -Scene : this is a scenegraph- you can have multiple per file -Object: a 'thing' in 3D space, has transformation, visibility, etc. Object datablocks have types (mesh/curve/armature/etc.) and may link to object-data type datablocks, such as:

-Mesh: Mesh data.. vertices, edges, faces and stuff -Curve -Armature: a bunch of bones -Lattice -etc...

there are also: -Material -Texture -World (kind of an environment material)

Data blocks link to each other, in a node graph, i.e. a scene links to an object links to a mesh, links to a material (or more) links to a texture (or more). You can have multiple links, i.e. many objects linking to the same mesh (this would be like instances) etc.

Datablocks have attributes or properties: Loc/Rot/Scale, shapes, vertex positions, etc. These can be animated.

When you animate attributes under a datablock, the animation is stored in an action- you'll see the datablock get's a link to 'animation-data' linking to a named action. this action is a collection of channels, each has a datapath that leads to the property you animated.

'other types' of relationship (than linking) are possible, like constraints, modifiers (all deformers in blender are modifiers, some of them have an object as a target, e.g. armature, lattice, curve deformer, others don't, e.g. wave deformer)

Interface

One way to think of the interface is not to view blender as a simple / single application, but as a desktop environment split into panes (regions or windows) that do not overlap, but you can rearrange, split and merge, etc. each pane has a header, and at the left of the header you can select what kind of 'program' or editor runs in that pane: a 3D view, Graph editor, Properties editor, etc. Each one will have it's own interface, menus, etc. but they will tend to share ui conventions, so they feel cohesive. this is very flexible for ui arrangement. Indeed, ui arangements or 'screens' are datablocks (See above) and can be saved with files or in user defaults. You can have lots per file and switch between them.

User Preferences

File->User Preferences. Here you can change settings/paths, customized keymaps, change interface colors and install addons.

Keymaps

Blender has customizable keymaps:

If you right click on a key or menu item, you can change it's shortcut for your session. To make that change stick, you should (in user preferences) unlock that keymap for editing, and then save user settings

You can change them in user preferences: File->User Preferences-> Input.

But you can also download and install pre-made keymaps. Here's a good one, that modifies the keys for viewport controls and transformations (and keying):

Linky it has the download and also a table to show you what he changed.

  • After downloading it you need to save it to your scripts folder.
    • Launch Blender
    • do help-> system info
    • Open a blender text editor, and click on the little text icon next to the 'New' Button in the header, and open system-info.txt
    • you should see the file path for your scripts folder, among other things.
  • In Explorer/Finder/Nautilus/Dolphin/a terminal/whatever, save the keymap file to that folder.
  • relaunch Blender
  • File->User Preferences->Input
  • click on the middle button that should say Blender by default, and switch it to the new Blender to Maya preset (not the blender default Maya one)
  • click on all the buttons that say 'Edit' that are visible underneath
  • click on Save User Preferences

Blender's keymaps distinguish the Numpad (left of keyboard) keys from the Number keys and symbols near the Letters. If you don't have a numpad (laptop) there's a user preference in Input 'emulate Numpad' that is slightly more convenient. Numpad keys mainly are there for manipulating the view, i.e. Top/Left/Right/Front etc. as well as viewing selected items, etc.

There are also tiny USB numpad you can buy for a numpadless laptop.

FAQ

General

Q How do I find out hotkeys ?

A Your best bet is to look in the menus/buttons. the hotkeys are displayed in the menus, or in tooltips on some buttons (if they have hotkeys). When asked, I'll probably resort to pointing you to the menu, since keymap changes may change the actual key for each user.

Q How do I move around in the timeline?

A Many ways:

  • left/right arrow is frame forward/back
  • up/down arrow is 10 frames forward/back
  • you can jump to next keyframe/ next marker/etc (check the timeline window)
  • if you have maya hotkeys/left mouse select you can right mouse scrub in any time window (timeline/graph editor/dopesheet/etc.) If you have blender defaults, left mouse to scrub.

Q Is there a reference like in maya?

A Yes, we call it Libraries or Linked Libraries. It should be already set up for you guys, but just for reference:

  • You can link datablocks (objects/meshes/groups/scenes/etc. from other files)
  • They are called library links or library data.
  • You can't edit them except in their original file.
  • For groups, you can create a local proxy for an item in the group, and edit that. This is how posing referenced (linked in blenderese) characters works.
  • We have a script in the tube project that automates this called 'reference desk'

Graph Editor

Q Can I used Stepped keys? What type of keyframes does blender support?

A Yes, Stepped keys are called 'Constant' in blenderese. you can change the keyframe interpolation for selected keyframe/s in the graph editor or in the dopesheet/action editor (Look for Interpolation Mode in the Key menu in either editor).

Q So what types of interpolation are there?

A Blender supports Constant (i.e. stepped), Linear and Bezier interpolation

Q Can I change the default interpolation to e.g. stepped/constant?

A Yes, go to File->User Preferences->Editing, and look for New F-Curve Defaults.

Q What are all the Bezier handle types?

A There's Free (a.k.a broken tangents), Aligned (a.k.a. smooth tangents), Vector (like free but the handles point at the previous/next keyframes- causes linear interpolation with bezier handles), Auto (automatic tangents) and Auto Clamped ( similar to Auto but with overshoot prevention)

Q How do I select a key in the graph editor? A The basics of selection:

  • click on a key (left or right depending on your user preferences) to select it.
  • shift select to select multiple keys (or handles)
  • you can rectangle select with the B key, check the Select Menu for many other ways to select.

Q How can i select more them one key?

A You can shift select, or box select, you can also select all the keys on the same frame, or all the keys on the same curve (check the Select menu for how), you can also select all keys after the current frame or before it, for hotkeys, check the select menu

Q How to box select?

A It's called 'Border' in the menu. If you want to select the handles alone, you need 'Border Include Handles'

Q How do I move/transform selected keys?

A check the Key->Transform Menu for the commands (and hotkeys)

Q How can I frame in the curve or selected key in the graph editor?

A View-Selected ( you can see the hotkey here)

Q To smooth the curve after the blocking is done i need to go to key->interpolation mode?

A Yes, it works on selected keys, so make sure you select everything first.

Posing/Keying

Q I get a list of attributes to key when I hit insert keyframe.. what's up?

A These are called keying sets. for a detailed explanation, visit the coder's blog

Q I like to key the entire character at once, can I do that?

A Simple answer: yes. Just pick the entire character keying set.

Q Can i move a controler in all directions at once ?

A Yes, though it's hard for me to tell how if you're using the Maya Keymap :) Go to Object (or Pose) -> Transform and find the hotkey for Grab/Move (or rotate or scale) this will initiate a free move. If you have the Translation widget, clicking and draging in the white circle will initiate a free move. For rotation, it will cause a tumble, but clicking and dragging the outer white circle will cause a screen-space rotation. For scale, it will cause uniform scaling.