Dforce Surface Prop...
 
Notifications
Clear all

Dforce Surface Properties (Surfaces pane)

 

(@panda-montok)
Eminent Member Admin
Joined: 9 years ago
Posts: 36
Topic starter  

Simulation/Surface

  • Visible in Simulation
    • Type: Bool
    • Default Value: true
    • Notes:
      • Describes whether or not the mesh associated with the surface is considered by the engine during the simulation
      • Dynamically hides/shows all other Simulation properties
  • Friction
    • Type: Float
    • Default Value: 0.4
    • Default Range: [0.001, 0.999]
    • Notes:
      • Describes the resistance that one surface encounters when moving across another
        • Inherently involves two (2) surfaces
        • Each surface describes its own contribution
        • Total friction between two surfaces is calculated as the average of both surfaces (this is an approximation, it is not physically correct)
      • Lower values allow vertices to move more freely, approximating “slick” materials like silk and satin
      • Higher values approximate materials which tend to slide less along the body, such as leather and denim

Simulation/Structure

  • Dynamics Strength (see Known Issues)
    • Type: Float
    • Default Value: 1.0
    • Default Range: [0.0, 1.0]
    • Notes:
      • Describes the amount of deviation (relative to the unsimulated mesh) that a vertex is allowed
      • A value of 1.0 allows vertices to move freely as a result of simulation forces
      • A value of 0.0 prevents vertices from moving away from their unsimulated positions
      • Useful for keeping a surface in-place while still permitting it to respond to the simulation
      • Recommended that fabrics be set to 1.0, while attached accessories such as belts, buckles, and buttons may provide better results at interim values
      • The Influence Weights map provides the ability to attenuate (reduce via multiplication) the effect that this property has on specific verticies of the mesh
  • Stretch Stiffness
    • Type: Float
    • Default Value: 0.8
    • Default Range: [0.01, 1.0]
    • Notes:
      • Describes the strength of a connection between each vertex in a mesh and the immediate neighboring vertices that the vertex shares an edge with (see image below)
      • Controls the amount of resistance to extension of an edge that is directly connected to a given vertex
      • The higher the value, the less a mesh will stretch in response to forces
      • Lower values, in combination with the Contraction-Expansion Ratio parameter, can be used to approximate “stretchy” materials such as elastic waistbands and spandex fabrics
      • Depends on the value of the global “Iterations” property; a higher number of iterations will result in firmer, stiffer materials
      • The Stetch Stiffness Weights map provides the ability to attenuate (reduce via multiplication) the effect that this property has on specific verticies of the mesh
  • Shear Stiffness (Quads)
    • Type: Float
    • Default Value: 0.2
    • Default Range: [0.01, 1.0]
    • Notes:
      • Describes the strength of an imaginary connection between each vertex in a mesh and the immediate neighboring vertices that the vertex does not share an edge with (see image below)
      • Controls the amount of resistance to lateral shifting and twisting of a given quadrangle
      • Only has an impact on quadrangles within a given mesh; has no impact on triangles (it would be redundant with Stretch Stiffness)
      • The Shear Stiffness Weights map provides the ability to attenuate (reduce via multiplication) the effect that this property has on specific verticies of the mesh
  • Bend Stiffness
    • Type: Float
    • Default Value: 0.5
    • Default Range: [0.01, 1.0]
    • Notes:
      • Describes the strength of an imaginary connection between each vertex in a mesh and the neighboring vertices of immediate neighbors that the vertex shares an edge with (see image below)
      • Controls the amount of resistance to extension of the imaginary connection described above
      • Higher values will result in broader folds and shapes which adhere more closely to their initial form
      • Lower values approximate thin and flexible materials which are able to change more dramatically from their initial shape
      • Depends on the value of the global “Iterations” property; a higher number of iterations will result in firmer, stiffer materials
      • The Bend Stiffness Weights map provides the ability to attenuate (reduce via multiplication) the effect that this property has on specific verticies of the mesh
  • Buckling Stiffness
    • Type: Float
    • Default Value: 0.05 (5%)
    • Default Range: [0.0, 1.0]
    • Notes:
      • Describes the amount of Bend Stiffness to use for resisting compression of the imaginary connection between each vertex in a mesh and neighboring vertices of immediate neighbors that the vertex shares an edge with (see image below)
      • Controls the amount of resistance to compression of the imaginary connection described above
      • The Buckling Stiffness Weights map provides the ability to attenuate (reduce via multiplication) the effect that this property has on specific verticies of the mesh
  • Buckling Ratio
    • Type: Float
    • Default Value: 0.7 (70%)
    • Default Range: [0.0, 1.0]
    • Notes:
      • Higher values result in materials that bend easily; e.g., silk
      • Lower values result in materials that attempt to maintain their initial form; e.g., denim
      • The Buckling Ratio Weights map provides the ability to attenuate (reduce via multiplication) the effect that this property has on specific verticies of the mesh
  • Density (GSM)
    • Type: Float
    • Default Value: 180.0
    • Default Range: Limitless
    • Notes:
      • Describes the weight (grams per square meter) for the associated mesh
        • Lightweight fabric (e.g., chiffon, linen, cheesecloth, lace, mesh, etc) is typically between 30-150 GSM
        • Medium weight fabric (e.g., sateen, oxford, velvet, taffeta, etc) is typically between 150-350 GSM
        • Heavyweight fabric (e.g., upholstery fabric, canvas, brocade, poplin, denim, etc) is typically 350+ GSM
      • Higher values will be less affected by air resistance and will impart more force onto collided and connected surfaces
      • The Mass Density Weights map provides the ability to attenuate (reduce via multiplication) the effect that this property has on specific verticies of the mesh
  • Contraction-Expansion Ratio
    • Type: Float
    • Default Value: 1.0
    • Default Range: [0.00001, 2.0]
    • Notes:
      • Describes the ratio that governs whether the edge rest lengths are biased toward contracting or expanding
      • > 1.0 will cause the associated mesh to expand/grow
      • < 1.0 will cause the associated mesh to contract/shrink
      • Values < 1.0 can approximate very form-fitting clothing; applying a value < 1.0 to a waistband or shirt cuff can cause that material to cinch around a figure more tightly
      • When combined with lower Stretch Stiffness, Shear Stiffness and Bend Stiffness values, lower values of this parameter can approximate spandex and other stretchy materials
      • Lowering this value a bit below 1.0 can greatly improve shape retention and reduce stretch in high polygon-count clothing, especially at lower Iteration counts

Simulation/Structure/Damping

  • Damping
    • Type: Float
    • Default Value: 0.1
    • Default Range: [0.0, 1.0]
    • Notes:
      • Used to reduce/prevent unwanted chaotic motion/oscillation (rabid wobbling of two vertices toward/away from each other) in all springs of a surface
      • Higher values can "calm" the motion of vertices during simulation, at the potential cost of realism
      • Scales the values of Stretch Damping, Shear Damping and Bend Damping
  • Stretch Damping
    • Type: Float
    • Default Value: 0.1
    • Default Range: [0.0, 1.0]
    • Notes:
      • Used to reduce/prevent unwanted chaotic motion/oscillation in the direction of Stretch springs
      • Scaled by the value of Damping
  • Shear Damping
    • Type: Float
    • Default Value: 0.1
    • Default Range: [0.0, 1.0]
    • Notes:
      • Used to reduce/prevent unwanted chaotic motion/oscillation in the direction of Shear springs
      • Scaled by the value of Damping
  • Bend Damping
    • Type: Float
    • Default Value: 0.1
    • Default Range: [0.0, 1.0]
    • Notes:
      • Used to reduce/prevent unwanted chaotic motion/oscillation in the direction of Bend springs
      • Scaled by the value of Damping

Simulation/Collision

  • Collision Layer (see Known Issues)
    • Type: Int
    • Default Value: 0
    • Default Range: [0, 100]
    • Notes:
      • Describes an ordering of surfaces for the purpose of collision detection, whereby a surface assigned to a layer with a higher value collides with the outside of surfaces assigned to a layer with a lower value, where a surface assigned to a layer with a lower value collides with the inside of surfaces assigned to a layer with a higher value, and where surfaces assigned to a layer with the same value collide with both the inside and outside of surfaces assigned to a layer with the same value
      • In cases that involve clothing colliding with a figure, the figure should typically be assigned to the lowest value in the stack (i.e., 0, default) and the value assigned to clothing items should increase as the distance from the body increases
  • Collide (for testing purposes only)
    • Type: Bool
    • Default Value: true
    • Notes:
      • Hidden
      • Controls whether or not the surface will be evaluated for collisions
  • Self Collide
    • Type: Bool
    • Default Value: true
    • Notes:
      • Dynamically hidden/shown based on value of "Collide"
      • Controls whether or not the surface will be evaluated for collisions within the same surface
  • Collision Offset
    • Type: Float
    • Default Value: 0.2
    • Default Range: Limitless
    • Notes:
      • Dynamically hidden/shown based on value of "Collide"
      • Describes the distance (in centimeters) that separates a simulated vertex and a collider
      • For example, a value of 0.5 will cause a clothing item to sit one half of a centimeter away from a figure
      • Lower values can produce more form-fitting results
      • Higher values can help prevent clipping between objects

Simulation/Smoothing

  • Velocity Smoothing
    • Type: Float
    • Default Value: 0.0
    • Default Range: [0.0, 1.0]
    • Notes:
      • Applies Laplacian smoothing to velocity vectors of each vertex that participates in the facets assigned to the surface
      • The range of this property represents the difference between the simulated velocity vector for a given vertex at the start of each subframe (0.0) and the smoothed velocity vector (1.0)
      • The Velocity Smoothing Weights map provides the ability to attenuate (reduce via multiplication) the effect that this property has on specific verticies of the mesh
  • Velocity Smoothing Iterations
    • Type: Int
    • Default Value: 0
    • Default Range: [0, 5]
    • Notes:
      • Specifies how many iterations of the Laplacian smoothing algorithm to perform
      • Smoothing operations are performed at the start of each collision iteration; so that the collision operation can attempt to correct any issues that are created by smoothing

Quote
Share: