The tySelect modifier allows you to create procedural selections of mesh sub-objects (vertices, triangles, polygons or elements), using various customizable criteria.
This modifier is meant to replace 3ds Max’s default “Volume Select” modifier, which is out-dated and lacking a lot of important features.
Sub-object level: this controls what type of sub-object the tySelect modifier will select.
Selection list: this is the list of selectors that will be evaluated from top to bottom.
The tySelect modifier has its own selection list (similar to 3ds Max’s modifier stack) which can be filled with selectors, each of which can have its own selection method and settings. The selection list is evaluated from top to bottom, and its purpose is to keep the tySelect modifier compact within 3ds Max’s modifier stack. So if you need to create a selection with various criteria (adding and subtracting sub-objects based on different selection methods), you’ll only need 1 tySelect modifier in the modifier stack to do it, which keeps the modifier stack tidy in cases where complex selections are generated.
Select at specific frame: when enabled, the input mesh will be evaluated at the specified frame, rather than the current frame.
Frame: the specified frame at which to evaulate the input mesh.
“Select at specific frame” allows you to perform deformation-independent selections on a deforming mesh. So, for example, if a particular selection would occur at frame 0, but not frame 20, you can replicate frame 0’s selection at frame 20 by enabling this setting and setting the selection frame to 0.
Assign to vertex colors: the resulting vertex selection values will be converted into color values and assigned to the mesh’s vertex color map channel.
Channel: the channel to assign vertex colors to.
The default vertex color channel is 0, but technically any channel can take vertex color values.
The additive selection parameters allow you to accumulate selections over time. The frames in the defined range will be evaluated and added together in succession, with their selections potentially decaying/fading as time progresses, depending on the temporal effect settings.
Start/End: the start and end frame of the additive selection interval.
Steps/frame: the number of time steps to sample/evaluate between frames during additive selection calculations.
The more steps per frame, the more accurate the overall selection will be (temporally). Increasing the steps parameter is most useful for increasing accuracy when selections are generated from fast-moving objects.
Decay: selection values will be decayed at this rate, over time.
Age curve: selection values will be interpolated along a curve by their age relative to a total lifespan value.
Decay multiplier: the multiplier applied to selection values over time.
Lifespan: the maximum lifespan of selection values.
Bake additive selections: computes the additive selections over the chosen frame range and stores them in memory.
Auto update: additive selections will automatically be computed when changes to the input geometry or tySelect settings are detected.
The profiler rollout shows info related to the total calculation time for each step of the tySelect selection process.
Selection Method: controls the way in which mesh sub-objects will be selected for the selected selector in the selection list.
Coverage (window/crossing): when window coverage is selected, all parts of a sub-object must be selected in order for the sub-object to be selected (for example, all vertices must be selected in order for a face to be selected, and all faces must be selected in order for an element to be selected). When crossing is selected, any parts of a sub-object can be selected in order for the sub-object to be selected.
Grow/Shrink: controls how must to grow or shrink a selection with adjacent sub-objects (grow with positive values, shrink with negative values).
Grow through edges: face selection will grow through edges that connect faces, rather than through vertices (this mode is only available when sub-object type set to triangles).
Ignore non-manifold edges: when face selection is set to grow through edges, selections will only be grown through edges that are manifold (edges that are connected to exactly 2 faces). Edges connected to 3 or more faces will bound the selection growth.
Set: sets the sub-object selection to the result of the selector.
Add: adds the result of the selector to the current selection.
Subtract: subtracts the result of the selector to the current selection.
Multiply: multiplies the result of the selector to the current selection.
Invert: inverts the result of the selector.
Changing the exponent setting from the default value of 1.0 is an easy way to crunch or inflate the influence amount of individual soft selection values.
Certain operations can produce vertex selection values outside the range of [0-1]. Sometimes this can be intentional, but other times it can be an unintentional consequence of the selector’s operation type. The clamp settings allow you to force resulting vertex selection values to be stay within a certain range.
Min: the minimum allowable vertex selection value after the selector’s operation has completed.
Max: the maximum allowable vertex selection value after the selector’s operation has completed.
Set keyframes on the activation parameter to animate a selector’s activation state over time.
Soft selections are only available in vertex sub-object mode, and emanate outwards from fully-selected vertices. Enabling soft selections will override any soft vertex selection values assigned directly by selectors.
Use Soft Selection: enables soft-selection value calculations.
Override existing: when enabled, existing soft-selections (selection values on vertices less than 1) will be overriden by the soft-selection algorithm, meaning that all soft-selections will derive from vertex selections equal to 1. When disabled, all vertex selection values greater than 0 will contribute to soft-selections. Disable this setting if you want soft-selections to extend from all vertex selection values, not just values equal to 1.
Linear distance: soft selection values will be computed as the distance from a vertex to the nearest fully-selected vertex, in worldspace.
Edge distance: soft selection values will be computed as the distance from a vertex to the nearest fully-selected vertex, along connected surface edges.
When soft-selecting in “edge distance” mode, any vertices that have no direct connection along surface edges to fully-selected vertices will always receive a soft-selection value of 0.
Include hidden: when enabled, the edge distance algorithm will traverse hidden edges. When disabled, it will skip them.
Distance: the distance value used to compute soft-selection ratios.
Curve: the curve used to interpolate soft-selection ratios along the distance, resulting in the final soft-selection value.
The bounds ratio selector computes selections by checking the ratio between each mesh element/triangle’s longest OOBB (object-oriented bounding box) axis and second longest OOBB axis. If the ratio between the longest OOBB axis and the second longest OOBB axis is greater than the threshold, the element/triangles’s face(s)/vertices will be selected. This computation allows you to identify select elongated mesh elements/triangles.
Element bounds: when selected, bounds of entire mesh elements will be measured.
Triangle bounds: when selected, bounds of individual mesh triangles will be measured.
Threshold: the length ratio threshold between the longest OOBB axis and the second longest OOBB axis.
The camera frustum selector computes selections by checking whether or not vertices/faces are visible within a camera’s field-of-view (FOV).
Camera node: the scene camera to use.
Expand: the amount of expand the camera’s FOV. Values larger than zero will select vertices/faces outside of the camera’s FOV.
The current selection selector imports the current selection stack as its selection. An example usage of this modifier, is if you want to re-compute soft selection values on a particular selection stack, in a way that is independent from the soft-selection methods previously computed. For example, the Mesh selector computes soft-selections by calculating surface proximities. This may not be ideal in situations where you want a soft-selection that is not relative to surface distances. So in that instance, you would use this selector to import the selection values of the Mesh selector, and re-compute the soft-selection.
Min: the minimum selection value to import.
Max: the maximum selection value to import.
Values less than 1 are soft-selection values.
The coincident faces selector computes selections by checking whether or not faces within a certain proximity to each other are overlapping.
Dist thresh: the maximum distance between two faces in order for them to perform an overlap test.
Thin face cull: faces with an angle between two edges smaller than this value will be ignored.
Very thin faces can return false-positive results in the overlap test. Culling thin faces like this will prevent them from being erroneously selected.
Check all faces: all faces will be compared to each other.
Check if same element: only faces of the same element will be compared to each other.
Check if different element: only faces of different elements will be compared to each other.
The curvature selector computes selections by measuring the angle between adjacent faces and comparing the result to user-defined threshold parameters.
Min/Max angle: faces whose adjacency angle is between these values will be fully selected.
Falloff: faces whose adjacency angle is outside of the min/max threshold but within this falloff threshold will have their vertices partially selected, depending on how close their angle is to the min/max threshold.
The deformation selector computes selections by comparing the input mesh to a reference mesh at a certain point in time. The greater the distance between mesh vertices, the stronger the selection. For example, it can be used to compute selections for stretched or creased areas of an animated mesh.
Ref frame: the frame at which the reference mesh will be analyzed.
Self: the reference mesh will be an internal snapshot of the current mesh evaluated at the reference frame.
Mesh: the reference mesh will be the mesh of an external object evaluated at the reference frame.
Deformations can only be computed on meshes with identical topology. If the meshes do not have identical vertex counts, the deformation selection cannot be performed.
Vertex distance: the selection will be computed by comparing distances between vertices of the reference/input meshes.
Edge bend: the selection will be computed by comparing angles between edges of the reference/input meshes.
Edge length: the selection will be computed by comparing differences between the lengths of edges in the reference/input meshes.
Face area: the selection will be computed by comparing differences between face areas in the reference/input meshes.
Threshold: the type-dependent selection threshold. For example, it is used as an angle threshold in “edge bend” mode, and a length threshold in “edge length” mode. For face area mode it is used as a ratio (for example, a threshold of “2” means input faces with twice the area of their counterpart in the reference mesh will be selected).
Absolute/relative: controls whether the measured differences will be absolute values in the selected spatial coordinates, or values relative to adjacent vertex neighbors.
Local/space: controls whether differences will be measured in local (mesh) space coordinates, or world space.
Selection strength values are available in “edge length” mode.
Stretch: a multiplier which controls the amount that stretched edges will contribute to the selection.
Compress: a multiplier which controls the amount that compressed edges will contribute to the selection.
The edge count selector selects sub-objects based on how many adjacent edges they are connected to.
Threshold: a soft-selection will be generated based on the number of adjacent edges compared to a threshold value.
Min/Max: elements with an adjacent-edge count within the min/max range will be selected.
The edge loop selector recursively selects edges adjacant to existing edge selections based on their angle of divergence.
Threshold: the maximum amount of divergence an edge can have from a selected edge in order to be included in a selection loop.
Visible edges only: when enabled, hidden edges will not be added to selection loops.
Allow branching: when enabled, all adjacent edges that diverge less than the threshold value will be added to the selection. When disabled, only the edge with the least amount of divergence will be added.
The edge length selector selects sub-objects based on the length of their adjacent edges.
Less than/greater than: the length condition.
Length: the length threshold.
The element triangle count selector selects sub-objects based on how many triangles are in the sub-object’s mesh element. A mesh element is a contiguous set of triangles.
Min: counts equal to the min value and above will be fully selected.
Max: counts equal to the max value and below will be fully selected.
Range: counts equal to the min value and above, or equal to the max value and below will be fully selected.
Soft vertex selection: elements with counts that didn’t qualify for a full selection will be soft-selected based on the ratio between their count and the count criteria.
The element size selector selects sub-objects based on the size of their mesh element. A mesh element is a contiguous set of triangles.
Surface Area/Volume: the element size type.
Min: sizes equal to the min value and above will be fully selected.
Max: sizes equal to the max value and below will be fully selected.
Range: sizes equal to the min value and above, or equal to the max value and below will be fully selected.
Soft vertex selection: elements with sizes that didn’t qualify for a full selection will be soft-selected based on the ratio between their size and the size criteria.
The every nth selector selects sub-objects based on repeating patterns. For example, an nth value of “2” will select every other sub-object. An nth value of “3” will select every third sub-object, etc.
Nth: the pattern value to use.
Offset: the offset to apply to the input sub-object index, prior to pattern matching.
The every nth selector uses the modulus operator to compute pattern matches. The selection condition equation is: (([sub-object index] + offset) % nth) == 0
The face angles selector computes selections based on the angles between the edges of mesh faces. If all three pairs of adjacent edges within the same face have an angle within the defined min/max thresholds, the face will be selected.
Min: the minimum angle between face edges in order for a face to be a candidate for selection.
Max: the maximum angle between face edges in order for a face to be a candidate for selection.
The face area selector selects sub-objects based on the area of mesh faces.
Min: areas equal to the min value and above will be fully selected.
Max: areas equal to the max value and below will be fully selected.
Range: areas equal to the min value and above, or equal to the max value and below will be fully selected.
Soft vertex selection: faces with areas that didn’t qualify for a full selection will be soft-selected based on the ratio between their area and the area criteria.
The gizmo selector selects sub-objects using a gizmo sub-object. Sub-objects encompassed by the gizmo sub-object will be fully selected.
The material ID selector selects sub-objects using face material ID values.
The mesh selector selects sub-objects using the meshes of external scene objects.
Enable “use soft selection” in the soft selection rollout in order to interpolate mesh proximity values as vertex soft-selection values.
Select if inside: vertices inside the input meshes will be fully selected.
Split elements: when enabled, mesh elements will be tested individually (leading to more consistent results when using complex/non-manifold meshes as the selection source).
Accuracy: the accuracy of the inside test. Increase this value for meshes that are self-intersecting or have holes in them.
Multiply by UVW values: when enabled, the selection result will be further multiplied by the specified UVW component of the specified map channel at the nearest point on the input mesh.
Average/U/V/W: controls which component of a mapping value the selection multiplier will be taken from.
Map channel: the map channel from which to derive the UVW values.
The noise settings allow you to offset the way in which vertex positions are measured during the distance/volume tests.
The normals selector selects sub-objects based on the direction of mesh face normals.
Gizmo direction: the direction vector of the gizmo sub-object determines which face normals will be selected.
Closest normal on surface: the closest normal on the selected surface to the center of the source face will determine which face normals will be selected.
Absolute X/Y/Z: the vector defined by the X/Y/Z spinners will determine which face normals will be selected.
Towards/Away/Both: controls the manner in which face normals must align to the test vector in order to be selected.
Threshold: faces with normals which align to the test vector within this threshold will be selected. The greater the threshold value, the less exact an alignment must be in order for a face to be considered a selection candidate.
The noise settings allow you to offset the way in which normals are measured by the normals selector.
The occluded elements selector selects sub-objects based on whether or not all vertices of a mesh element are occluded by other parts of the mesh.
This selector makes it easy to select mesh elements that are inside of other mesh elements, or mesh elements whose normals are flipped inside-out. An example usage would be selecting all interior faces/elements of a blobmesh created by a tyMesher.
The occlusion test is performed by casting rays out from vertices of the mesh. If a vertex doesn’t hit a face, it is deemed un-occluded by the mesh. Increasing the accuracy parameter increases the number of rays cast from each vertex, which increases the probability that a vertex which is not completely occluded by parts of the mesh will have rays which escape without hitting a face.
The “single ray per element” test is very fast, but only works on meshes with elements that are not intersecting. For more complex meshes (self-intersecting, non-manifold, etc), this test won’t return accurate results.
Occlusion %: the minimum percent of vertices within a mesh element that must be occluded by parts of the overall mesh, in order for the element to be selected.
Accuracy: the number of rays to cast from each vertex, to test for occlusion.
The occluded faces selector selects sub-objects based on whether or not all vertices of a face are occluded by other parts of the mesh.
This selector makes it easy to select mesh faces that are inside of mesh elements. An example usage would be selecting all interior faces of a blobmesh created by a tyMesher.
The occlusion test is performed by casting rays out from every vertex of the mesh. If a vertex doesn’t hit a face, it is deemed un-occluded by the mesh. Increasing the accuracy parameter increases the number of rays cast from each vertex, which increases the probability that a vertex which is not completely occluded by parts of the mesh will have rays which escape without hitting a face.
In general, a ray cast outward from inside of a closed mesh will only ever penetrate an odd number of faces in order to escape the mesh volume - this is why regular occlusion (not ‘any hit’ occlusion) only considers oddly-numbered hit counts as occluded.
Occlusion %: the minimum percent of vertices within a face that must be occluded by parts of the overall mesh, in order for the face to be selected.
Accuracy: the number of rays to cast from each vertex, to test for occlusion.
The open edges selector selects sub-objects based on whether or not they are touching an open edge. An open edge is an edge with only one adjacent face. This selector has no settings.
The particles selector selects sub-objects using the particles of external particle systems.
Absolute radius: sub-objects within an absolute radius to particles will be selected.
Radius: the absolute radius value to use.
Particle radius: sub-objects within each particle’s radius will be selected.
Multiplier: a multiplier to apply to each particle’s radius.
Multiply by density: when enabled, the strength of the selection will depend on how dense the particle cloud around a particular vertex is, based on the specified threshold.
Threshold: the number of particles that must be in proximity to a particular mesh vertex, to result in a full vertex selection. Vertices with particle densities below this threshold will be softly selected.
Multiply by age: when enabled, the strength of the selection will depend on how old each proximite particle is.
Age caching must be enabled on the input tyFlow particle system for this feature to work.
Threshold: the minimum age a proximate particle needs to be, to result in a full vertex selection.
Invert: inverts the effect of the “multiply by age” setting, so that older particles contribute less of an effect on selections.
The pinched vertices selector selects vertices that are connected to three or more open edges.
Pinched vertices most often occur where two isolated triangles are welded by a single vertex.
The polygon vertices selector selects a certain number of each polygon’s vertices.
Count: the number of vertices in each polygon to select.
Seed: the seed value which controls the variation.
The random % selector selects a random percentage of sub-objects.
%: the random percentage of sub-objects to select.
Seed: the seed value which controls the randomness.
The raycast selector selects sub-objects based on whether or not faces are hit with rays emanating from a gizmo sub-object.
The relax selector applies a relaxation kernel to current vertex selections, which averages selection values between edge-adjacent vertices.
Amount: the amount to linearly-interpolate current selections to post-relax selection values.
Iterations: the number of times to run the relaxation kernel over the current selection.
The self-proximity selector computes selections based on the distance of vertices to other vertices within the same mesh.
Distance: vertices within this distance to each other will be fully selected.
Falloff: vertices whose distance is further than the distance threshold, but within the falloff threshold, will be partially selected.
Ignore same element: vertices within the same mesh element will ignore each other.
Ignore adjacent vertices: vertices whose edge connectivity is within a certain depth threshold to each other will ignore each other.
Depth: the vertex connectivity depth threshold.
The self-intersections selector computes selections based on whether or not vertices are found to be intersecting their mesh.
The smoothing groups selector selects sub-objects using face smoothing group values.
The stack selection selector selects sub-objects using existing selections present in the modifier stack.
Vertices: existing vertex selections will be used to select sub-objects.
Triangles: existing triangle selections will be used to select sub-objects.
The texmap selector selects sub-objects using the monochromatic intensity values of a texmap.
Texmap: the texmap to sample per-vertex values from.
Min: texmap values equal to the min value and above will be fully selected.
Max: texmap values equal to the max value and below will be fully selected.
Range: texmap values equal to the min value and above, or equal to the max value and below will be fully selected.
Absolute: texmap values will be converted directly into selection values.
Seed: the seed value which controls the variation.
Soft vertex selection: vertices with texmap values that didn’t qualify for a full selection will be soft-selected based on the ratio between their texmap value and the texmap value criteria.
The UVW seams selector selects sub-objects that are on the open edges of map channel faces.
The UVW values selector selects sub-objects using values (0-1) assigned to the mapping channel of a mesh.
Average/U/V/W: controls which component of a mapping value the selection value will be taken from.
Map channel: the map channel from which to derive the UVW values.
The follow MAXScript commands can be used to access tySelect functions:
[tySelect modifier].addSelector()
[tySelect modifier].removeSelector: integer (0-based index of selector in list)
[tySelect modifier].setSelectorEnabled: integer, bool (0-based index of selector in list and true/false value to set enabled state)
[tySelect modifier].bakeAdditiveSelections()