The Complete Guide to Blender Graphics

Supplement-10

2D Character Animation using Armatures

In explaining how to animate 2D Drawings using Armatures the method will be the main focus rather than the detail. The work flow will be basic and the drawing will be very crude.

In this demonstration an image will be loaded into the Blender file as a template for tracing a character to animate. You may use any image as a template or you can draw something original.

The following images have been scanned from a magazine and give a clue to the procedure.

What you see in Figure 10.1 are components of the character drawn as individual items. In setting up an animation each component will be drawn on a separate Layer and left in situe within the profile of the character. An Armature will be introduced and the individual Bones making up the Armature will be assigned to a Layer. By manipulating Bones (Posing), Layers are manipulated, Keyframes inserted and an Animation is created.

Easy peasey , as the man said. Work through the following exercise to see how.

Open your Screen arrangement file GP_Animation.blend created in Supplement 08. Rename the file and save it (e.g. 2D_Character_Animation.blend).

To simplify this demonstration not all the components shown in Figure 10.1 will be created or animated.

Recap on the components of the Blender Screen in your 2D_Characte_Animation.blend file. You have the Tools Panel, Grease pencil tab at the far left of 3D window. Adjacent to the Tool Panel you have the Properties Panel (Not the Properties window) containing the Grease Pencil Layers and Grease Pencil Colors tabs. The main part of the 3D window is in Camera View. At the far right of the Screen the Outliner and Properties windows are parked to the side. The Timeline window is displayed across the bottom of the Screen.

Components CharacterFigure 10.1

Image as a Template

You may use any image saved on your computer as a template for drawing components of a character.

In the Properties Panel, Background Images tab check (tick) Background Images (Figure 10.2). Click Add Image to expand the panel then click Open. Navigate in your File System, select and open the image you wish to use.

In Figure 10.2 the image is a Screen Capture of the character in Figure 10.1.

When the image is loaded in Camera View it may be distorted (Figure 10.3).

The Properties Panel, Background Images tab has expanded further. Click in Fit to get the image back in shape (Figure 10.4).

Draw Components

You draw the components of your character, that you wish to animate, by drawing Strokes on separate Layers.

Remember: Overlap components. You can organise which component is in front or behind another by adjusting the Layer order in the Layer stack.

Draw the Hat

In this example start with the Hat. In the Grease Pencil Layers tab change the default GP_Layer name to Hat (Figure 10.5).

In drawing Strokes the Data Source will be Scene and the Stroke Placement will be Cursor. This will be the same for all Strokes.

Figure 10.2

Figure 10.3

Figure 10.4

Figure 10.5

The Strokes for the Hat will be drawn on the Layer named Hat.

In the grease Pencil Colors tab you can change the name Color to Hat.

Naming Layers and Colors will help when the parts of the interface grow and become involved.

The Hat is black, the Stroke color is by default black but the Fill color is white. Leave the Fill as white for the moment.

Draw the Stroke (Figure 10.6). Increase the Opacity value to show the white color than change the Fill to black.

Draw the Head

Add a new Layer and name it Head (Figure 10.8).

Add a new Color channel and name it Head (Figure 10.9).

Figure 10.5

Figure 10.6 Figure 10.7

Stroke: Black Fill: White with Opacity 1.000 Fill: Black with Opacity 1.000

Figure 10.8

Click to add a new Layer

Click to add a new Color Channel

In the new Color Chanel named Head, leave the Stroke color black but change the Fill color to resemble the template image.

Figure 10.9

Trace the Head profile overlapping the Hat (Figure 10.10).

Remember: The Mouth, Hair and Eye are all drawn on the same Layer as the Head (Figure 10.11).

Note: In Figure 10.11 the Mouth is drawn using the Hair Color Channel. If you don't want the Fill showing add a new Color Channel with Stroke: Black and Fill: White and leave the Fill Opacity at 0.000.

Figure 10.10

Overlap the Hat.

Draw the Stroke, tracing the profile of the Head with the Opacity value at a minimum. Increase the Opacity to check the Head.

Figure 10.11

Figure 10.12

Figure 10.13

Figure 10.12 shows the Color Channels used for Figure 10.13.

As you see the Color Palette can grow to a considerable size, therefore, naming colors to match the components of a figure is beneficial.

Note: The Hat overlaps the Head. Body overlaps Head. Arm overlaps Body. Skirt and Boots overlap Body.

Reduce the Opacity for the Fill color, then trace the Mouth, Hair and Eye creating new Color Channels as required. The Eye consists of three separate components; The Eye, the black Eyeball and the white highlight.

Draw other Components

Continue by drawing the remainder of the components on new Layers overlapping as required (Figure 10.13).

To have a component move independently in the final animation, draw it on a New Layer. Where yo want components to move with other components draw them on the same Layer.

In this exercise the Arm, Hand, Star and the Wand Handle are all on the Same Layer. The Wand handle is drawn as four separate Strokes.

Organise the Layer Stack

With all components drawn on their Layers, rearrange the Layer Stack to have the components overlap in the correct order (Figure 10.14).

To move a Layer up or down in the Stack, select the Layer (highlight blue) then click on the arrows.

Remember: Layers at the top of the Stack are behind layers below. For example the Skirt Layer at the top of the Stack is behind the Body Layer. The Hat is in front of the Head.

Final Color Palette

Figure 10.15 shows the final Color Palette for the figure.

Layers Before Arranging

Layers After Arranging

Figure 10.14

Figure 10.15

Wand Handle – Four separate Strokes

Animation using Armatures

Animating the Layers will make it appear as though the components of the character are moving. Armatures will be employed in this process which facilitate F-Curves which can then be modified to control the movement.

To start the process, in the 3D window (in Camera View) add an Armature – Single Bone. The Armature is placed at the location of the 3d window cursor which in your GP_Animation.blend file is located just outside camera View at the bottom of the Screen. In Drawing Strokes the Stroke Placement type has been Cursor which means all Layers have been created in the same plane as the 3D window cursor and in placing the Armature it is also in the same plane (Figure 10.17).

Have the Armature – Single Bone selected. Position, scale and extrude to create the Multi Bone Armature shown in Figure 10.18.

The size and location of Bones does not have to be exact. The important thing to remember is; a Bone will be rotated about the center of its base, therefore, the component on its Layer will also rotate about that point.For example the characters arm, hand and wand will all rotate from the base of the Bone (Figure 10.18).

Figure 10.17

3D window in Right Orthographic View.

Stroke Layers

Armature – Single Bone

Figure 10.16

Remember the Properties window and the Outliner window have been parked at the RH side of the Screen. Drag the edge to display these.

In the Properties window, Data buttons (Armature selected), Display tab, check X-Ray (Figure 10.16).

Armature – Single BoneScaled and Repositioned

Armature – Multi BoneExtruded from Base and Tip

Figure 10.18

Rotation point for the Arm

In the Outliner window under Armature you will see all the Bones listed (click the + next to Armature and all its sub entries) (Figure 10.19).

With a Bone selected in Pose Mode you will see the Bone in the Outliner window indicated by a little circle preceding the name. This is to be a very useful way of selecting a Bone.

To animate the Layers containing the components of the character you Parent the Layer to the Bone. You then Pose the Bone at different Frames in the Timeline window and insert Keyframes.

Start with the Layer containing the Arm, hand and Wand.

You have already named the Layers indicating which components are on a Layer.

Parent Layers to Bones

Select Layer – Arm from the Grease Pencil Layers tab (Figure 10.20).

Figure 10.19

Figure 10.20

Click and select Armature from the menu to enter Armature,

Click

Click Object and select Bone

Have the Arm Bone selected in Pose Made. You will the highlighted circle in the Outliner window next to Bone.004. Cick the panel with the Bone icon in the Grease Pencil Layers tab and select Bone.004.

Bone.004 is entered in the panel.

This procedure has Parented the Layer – Arm to Bone.004

Repeat the procedure Parenting the remaining Layers to the appropriate Bones.

Posing and Inserting Keyframes

In the Timeline window be at Frame 1.

Have the Armature selected in Pose Mode. Go through the Armatures selecting in turn any Bone that you intend to Pose by Rotating. With each Bone selected, go to the Properties Panel, Transform tab and change Quaternion (WXYZ) Rotation Mode to XYZ Euler (Figure 10.21).

Changing Quaternion to Euler will allow you to apply Cyclic Extrapolation to the F-Curves produced when animating Bones by inserting Keyframes.

Having changed the Rotation Mode for all Bones, select the entire Armature and with the cursor in the 3D window press the I key and select Insert Keyframe - LocRot from the menu.

A Location and Rotation Keyframe is entered for each Bone in the Armature at Frame 1 in the Animation.

Move the Timeline window cursor to another frame (Frame 10). Select individual Bone (in Pose Mode) and rotate to create a different Pose. Select all Bones and insert a second Keyframe.

Repeat the process for a number of poses at different Frames in the Timeline window (Figure 10.22).

You may press the Play button in the Timeline window header and see your Witch twitch. She only twitches for the number of Frames at which you have inserted Keyframes. In Figure 10.22 this from Frame 1 to Frame 40. The animation plays through to Frame 250 (the End Frame) with no further movement then repeats.

To extend the animation, without the laborious process of inserting more Keyframes; one method is to apply Cyclic Extrapolation.

Extrapolation

Divide the 3D window in two and make one part the Graph Editor window (Figure 10.23)

In F-Curve mode you will see all the F-Curves for the Animation Keyframes.

Figure 10.21

Figure 10.22

Keyframes

Figure 10.23

F-Curve Mode

F-Curves

Hone in on one single Armature Bone. In the 3D window. Deselect the Armature and select one Bone. Select the Hat Bone ( Bone.003). The Graph Editor window will display the the single F-Curve for Bone.003 for the Keyframes (Frames 1 to 40) (Figure 10.24).

Remember: The Rotation Mode for the Bones in the Armature has been changed to Euler Rotation.

To apply Extrapolation; With the Mouse cursor in the Graph Editor window, press the N key to display a Graph Control Panel at the RH side of the Graph Editor window. In the panel click on the Modifier tab, click Add Modifier and select Cycles from the menu (Figure 10.25). The F-Curve for Bone.003 is repeated before Frame 1 and after Frame 40 to infinity (Figure 10.26).

Figure 10.24

Frames 1 to 40

F-Curve for Bone.003

Figure 10.25

Figure 10.26

Repeat the procedure for each Bone that has been animated.

With all F-Curves having Cycles Extrapolation applied, playing the animation will show your Witch Twitching performing a merry dance. You may render the animation and introduce a sound file for music to enhance the visual effect.

Computer Screen

Figure 10.27

Figure 10.28Final Computer Screen Arrangement