¶AdnGlue

AdnGlue is a Maya node that can be used to attach multiple muscles together. This solver uses as input a series of simulated muscles and allows the user to define glue connections between those muscles by using a maximum glue distance value and painted maps.

There are two differentiated modes that this solver can run in:

• Static. The solver ingests the input geometry data at each simulated frame and computes the glue connections, as well as the distance, shape and volume constraints directly over the point positions of that input geometry data. There is no influence of gravity nor inertia propagated from one frame to the next one.
• Dynamic. The solver behaves as a standard time-dependent simulation solver where the external forces (i.e. gravity) are integrated to introduce inertia to the system. The input geometries become a target geometry used by the solver to compute soft constraints against. Glue, distance, shape and volume constraints are computed too. By default, the AdnGlue runs in static mode, but there is a boolean attribute exposed to allow switching to dynamic mode.

The maps required to control the AdnGlue solver can be painted using the standard Maya Paint tool.

¶How To Use

The AdnGlue node can be applied to any set of geometries. For each geometry, their mesh at each frame is gathered and simulated to ensure the original distance between the neighboring geometries. This is achieved by creating attachments between each vertex of a geometry and the closest point on the surface of one of the other geometries (the closest one). More aspects are then computed to ensure that the simulated output preserves the original shape and edge-lengths of the simulated meshes. The output of the node is a mesh that combines all the input geometries together and adds the results of the solver.

To create an AdnGlue node within a Maya scene, the following inputs must be provided:

• Input Geometries (IG): List of geometries to be simulated and attached together by the glue solver.

The process to create an AdnGlue node is:

1. Select the Input Geometries.
2. Press in the AdonisFX shelf or the Glue action in the AdonisFX’s Solvers menu, under the Create section.
3. A message in the terminal will notify you that AdnGlue has been created properly, meaning that it is ready to simulate with default settings. Check the next section to customize their configuration.

¶Attributes

¶Solver Attributes

¶Time Attributes

¶Scale Attributes

¶Gravity

¶Advanced Settings

Override Constraint Stiffness

Mass Properties

Dynamic Properties

Self Collisions Properties

¶Maps

¶Node Attributes

¶Debug Attributes

¶Attribute Editor Template

¶Paintable Weights

In order to provide more artistic control, some key parameters of the AdnGlue solver are exposed as paintable attributes in the node. The Maya paint tool must be used to paint those parameters to ensure that the values satisfy the solver requirements.

¶Debugger

In order to better visualize node constraints and attributes in the Maya viewport there is the option to enable the debugger, found in the dropdown menu labeled Debug in the Attribute Editor.

To enable the debugger the Debug checkbox must be marked. To select the specific feature you would like to visualize, choose it from the list provided in Features. The features that can be visualized with the debugger in the AdnGlue node are:

• Distance Constraints: For each pair of vertices forming a constraint a line will be drawn. If the Triangulate Mesh option is disabled the debugged lines will align with the edges of the mesh polygons. If the Triangulate Mesh option is enabled the debugged lines will align with the edges of the underlying triangulation of the mesh.
• Glue Constraint: A line will be drawn for every vertex to the closest point on the closest neighbor surface.
• Self Collisions Volume: For each vertex, a sphere will be drawn representing the volume that will collide if its Self Collision Point Radius Multiplier weight and the Point Radius Scale are greater than 0.0.
• Shape Preservation: For each vertex with a shape preservation weight greater than 0.0, a line will be drawn from each adjacent vertex to the opposite adjacent vertex.
• Soft Constraints: For each vertex, a line will be drawn from the simulated mesh vertex to the corresponding point on the target mesh if its Soft Constraints weight is greater than 0.0.
• Acceleration Structure: For each level in the acceleration structure used to solve self-collisions, display a box representing the bounding box encapsulating all the collision primitives in that level. If the value of Debug Level Acceleration Structure is -1, then all levels are displayed. Otherwise, only the specified level is displayed. If the value is greater than the number of levels, then no levels are displayed.
• Rest Self Collisions: For each triangle intersecting with the mesh at rest, the 3 edges of the triangle are displayed.

¶Advanced

¶Inputs

Once the AdnGlue node is created, it is possible to add new inputs and remove currently connected ones.

• Add inputs:
  1. Select one or more mesh nodes to be assigned as inputs to the AdnGlue.
  2. Select the AdnGlue output mesh.
  3. Press Add Inputs in the AdonisFX menu from the Edit Glue submenu.
• Remove inputs:
  1. Select one or more mesh nodes that are assigned as inputs to the AdnGlue.
  2. Select the AdnGlue output mesh.
  3. Press Remove Inputs in the AdonisFX menu from the Edit Glue submenu.
  4. Alternatively, if only the AdnGlue output mesh is selected, when pressing the Remove Inputs button, all inputs will be removed.

¶Limitations

After creating the AdnGlue node, it may be possible to smoothen out the resulting geometry (generally called AdnGlue1_GEO). This can be done using an AdnRelax node or any other deformer to reduce artifacts (like deltaMush). In such cases, painting the AdnGlue weights on the output geometry using Maya's paint tool may not be possible. Here is a workaround to enable painting AdnGlue weights again:

1. Create a cube from the Poly Modelling shelf (remove the polyCube node and keep only pCubeShape1).
2. Using a script or the node editor, connect AdnGlue1.outputMesh to pCubeShape1.inMesh
3. Using a script or the node editor, connect pCubeShape1.outMesh to AdnGlue1_GEOShapeOrig.inMesh (the original mesh created by Maya after applying AdnRelax, for example).
4. To paint AdnGlue weights, select the pCube and follow the standard Maya procedure for painting weights. To paint AdnRelax weights, select the AdnGlue1_GEO and follow the same procedure.