This animation is deliberately longer and separate from the idle animation. This animation is meant to be played in a loop and is responsible for subtle breathing movements, wiggling of the tail feathers, as well as the bending of the branch and leaves to simulate wind. The down, up, left, and right animations are single frame animations, each representing an extreme pose to be additively blended with the other animations at runtime based on user input, for example based on the mouse cursor position like in the demo at the top of this page. The owl animations are designed to be played at the same time on different tracks and to use additive animation blending.
By giving each leaf its own bone, they can be easily animated to simulate a gentle breeze bending them. The leaf bones are parented to the branch bone closest to them. This allows smoother bending around the joints while retaining a rigid shape everywhere else.Įach leaf on the branch consists of a bone and image attachment. The branch has few vertices, except near the joints of the bones. The branch features a long mesh called wood which is weighted to a chain of bones, branch-1 through branch-6. While the feet of course belong to the owl, they are located outside the owl hierarchy and are parented to the branch-2 bone. The owl's tail consists of 3 images, feather-1, feather-2, and feather-3, which are parented to the tail-feathers bone, which itself is parented to the owl-base bone. The body-top-control bone is parented to the head bone, and owl-base is parented to branch-2. The body is composed of 3 meshes, body, L_wing, and R_wing, which are weighted to the body-top-control and owl-base bones. The body of the owl connects the head to the branch. The beak is composed of two attachments, beak and beak-down, and generally follows a similar setup as the eyes to simulate depth. To simulate the owl gazing at the control bone, the L_eye-pupil and R_eye-pupil images are parented to the bone control so that they follow it completely. All attachments except the pupils are weighted to the bones head and control letting the eyes contribute to the 2.5D effect without distortion, and moving proportionally to the control bones. The eyes are composed of a number of attachments: L_eye-iris, R_eye-iris, L_eye-closed, R_eye-closed, L_eye-pupil, R_eye-pupil, L_eye-light, and R_eye-light. Similarly, the external edge vertices were weighted to the control-back bone so that the feathers in the back move in the opposite direction of the rest of the face, giving the illusion of depth.
The middle of the mesh was then painted using weight painting in additive mode to become influenced by the control bone. As it is easier to start from a neutral state of weights, all the weights were initially set to be 100% influenced by the bone head. These vertices are bound to the 3 bones head, control, and control-back.
#Esoteric software spine full series#
Starting from the external edge, a series of concentric vertices were created to give the illusion of spherical head. The largest mesh, head-base, is used as a reference when weighting all the smaller meshes relative to it. The depth effect is added by weighting a mesh to these two opposite bones, as illustrated in the Cube tip. This results in the target control-back bone moving in the opposite direction of the control bone: The effect is accomplished using a transform constraint that lets the control-back bone follow the control bone with a translation mix set to -100. The other two bones, control and control-back, are used to create the 2.5D effect. The head bone controls the owl's head and can be used to easily translate, rotate, and scale the entire head. The head is composed of several images that are connected to 3 bones. The skeleton contains only a handful of images so focusing on the setup of the 3D effect and poses becomes easier. The project also employs techniques to give the skeleton a 3D look. Additive animation blending lets you create effects such as blending multiple facial expressions, such as 25% angry, 25% sad, and 50% happy. The Owl project shows one way to take advantage of additive animation blending.