BodyFracture Class

List of functions:

This class is used to simulate destructable fracture bodies. There are three patterns of the fracturing:

New surfces that are created when fracturing occurs are assigned their own material and properties.

NoticeFracture body can be used with meshes in form of a simple primitive: boxes, spheres,  capsules, cylinders, etc. Complex meshes cannot be fractured procedurally.

Fracture body is, per se, a rigid body and moves according to the rigid bodies dynamics.

BodyFracture Class

Members

BodyFracture ()

Constructor. Creates a fracture body with default properties.

BodyFracture (const Ptr<Object> & object)

Constructor. Creates a fracture body with default properties for a given object.

Arguments

const Ptr<Object> & object - Object represented with the new fracture body.

void addWorldForce (const Math::Vec3 & point, const Math::vec3 & force)

Applies a force to the given point of the body, that is specified in world coordinates. Integrated forces are applied after calling the update.

Arguments

const Math::Vec3 & point - Point of the body in world coordinates.
const Math::vec3 & force - Amount of force to apply.

float getAngularDamping ()

Returns the current damping of the body angular velocity.

Return value

Angular damping value.

int createSlicePieces (const Math::Vec3 & point, const Math::vec3 & normal)

Breaks the object into two slices, slitting the body according to the normal of the specified point.

Arguments

const Math::Vec3 & point - Point of contact.
const Math::vec3 & normal - Normal of the contact point.

Return value

Positive number if the object was successfully broken; otherwise, 0.

void addForce (const Math::vec3 & force)

Applies a force to the given point of the body, that is specified in local coordinates. Integrated forces are applied after calling the update.

Arguments

const Math::vec3 & force - Radius vector starting in the body's center of mass in local coordinates. Its end is the point of force application.

const char * getPropertyName ()

Returns the property for fractured verge surfaces appearing after breaking the body.

Return value

Property name for the fractured verges.

float getLinearDamping ()

Returns the current damping of the body linear velocity.

Return value

Linear damping value.

void setMaxAngularVelocity (float velocity)

Sets the maximum possible linear velocity for the body. If the value is lower than the engine.physics.setMaxAngularVelocity one, it is overridden.

Arguments

float velocity - Maximum possible angular velocity.

void setLinearDamping (float damping)

Sets the damping of the body linear velocity.

Arguments

float damping - Linear damping value.

void setMaxLinearVelocity (float velocity)

Sets the maximum possible linear velocity for the body. If the value is lower than the engine.physics.setMaxLinearVelocity one, it is overridden.

Arguments

float velocity - Maximum possible linear velocity.

float getFriction ()

Returns the current friction of the body against other surfaces.

Return value

Friction value.

void setDensity (float density)

Sets density of a body. Changing the density influences the mass, that is computed by multiplying body volume by density.

Arguments

float density - Density of the body.

void setCollisionMask (int mask)

Sets a collision bit mask for the body. Two objects collide, if they both have matching masks. See also details on additional collision exclusion mask.

Arguments

int mask - Integer, each bit of which is a mask.

void addForce (const Math::vec3 & radius, const Math::vec3 & force)

Applies a force to the given point of the body, that is specified in local coordinates. Integrated forces are applied after calling the update.

Arguments

const Math::vec3 & radius - Radius vector starting in the body's center of mass in local coordinates. Its end is the point of force application.
const Math::vec3 & force - Amount of force to apply.

float getDensity ()

Returns the current density of the body.

Return value

Density of the body.

const char * getMaterialName ()

Returns the material for fractured verge surfaces appearing after breaking the body.

Return value

Material name for the fractured verges.

void setMass (float mass)

Sets a mass of the body. Changing the mass influences the density, that is computed by dividing the mass by body volume.

Arguments

float mass - Mass of the body.

void setError (float error)

Sets approximation error permissible by creating convex shape for the mesh.

Arguments

float error - Approximation error. If a negative value is provided, 0 will be used instead.

void setBroken (int broken)

Sets a value indicating if the object is broken or remains its solid state.

Arguments

int broken - Positive number to indicate the object as broken; 0 for it to remain solid.

void setProperty (const char * name)

Sets the property for cracked verge surfaces appearing after breaking the body.

Arguments

const char * name - Property name for the fractured verges.

int getCollisionMask ()

Returns the collision bit mask for the body. Two objects collide, if they both have matching masks. See also details on additional collision exclusion mask.

Return value

Integer, each bit of which is a mask.

void setMaterial (const char * name)

Sets the material for fractured verge surfaces appearing after breaking the body.

Arguments

const char * name - Material name for the fractured verges.

float getMaxLinearVelocity ()

Returns the current maximum possible linear velocity for the body. If the value is lower than the engine.physics.setMaxLinearVelocity one, it is overridden.

Return value

Maximum possible linear velocity.

float getMaxAngularVelocity ()

Returns the current maximum possible angular velocity for the body. If the value is lower than the engine.physics.setMaxAngularVelocity one, it is overridden.

Return value

Maximum possible angular velocity.

Math::vec3 getWorldVelocity (const Math::Vec3 & point)

Returns the total linear velocity in the point specified in world coordinates.

Arguments

const Math::Vec3 & point - Point of the body in world coordinates.

Return value

Total linear velocity in the given point.

float getThreshold ()

Returns the current minimum volume threshold for breaking. If the piece volume is less than the threshold value, it cannot be fractured further.

Return value

Volume threshold.

int getExclusionMask ()

Returns the bit mask that prevents collisions of the body with other ones. This mask is independent of the collision mask. For bodies with matching collision masks not to collide, at least one bit of their exclusion mask should match.

Return value

Integer, each bit of which is a mask.

void setThreshold (float threshold)

Sets the minimum volume threshold for breaking. If the piece volume is less than the threshold value, it cannot be fractured further.

Arguments

float threshold - Volume threshold. If a negative value is provided, 0 will be used instead.

int createShatterPieces (int num_pieces)

Breaks the object into arbitrary shattered pieces.

Arguments

int num_pieces - The number of shattered pieces.

Return value

Positive number if the object was successfully broken; otherwise, 0.

void addWorldTorque (const Math::Vec3 & point, const Math::vec3 & torque)

Applies a torque to the given point of the body, that is specified in world coordinates.

Arguments

const Math::Vec3 & point - Point of the body in world coordinates.
const Math::vec3 & torque - Amount of torque to apply.

int isBroken ()

Returns a value indicating if the object is broken or remains its solid state.

Return value

Positive number if the object is already broken; 0 if it is still solid.

void addTorque (const Math::vec3 & torque)

Applies a torque to the given point of the body, that is specified in local coordinates.

Arguments

const Math::vec3 & torque - Radius vector starting in the body's center of mass in local coordinates. Its end is the point of torque application.

void setFrozenAngularVelocity (float velocity)

Sets angular velocity threshold for freezing body simulation. If body angular velocity remains lower than this threshold during the number of Frozen frames (together with linear one), it stops to be updated.

Arguments

float velocity - "Freeze" angular velocity. If the value is lower than the engine.physics.setFrozenAngularVelocity one, it is overridden.

void setExclusionMask (int mask)

Sets an bit mask to prevent collisions of the body with other ones. This mask is independent of the collision mask. For bodies with matching collision masks not to collide, at least one bit of their exclusion mask should match. 0 is to collide with all bodies with a matching collision mask.

Arguments

int mask - Integer, each bit of which is a mask.

void setAngularDamping (float damping)

Sets the damping of the body angular velocity.

Arguments

float damping - Angular damping value.

void setFrozenLinearVelocity (float velocity)

Sets linear velocity threshold for freezing body simulation. If body linear velocity remains lower than this threshold during the number of Frozen frames (together with angular one), it stops to be updated.

Arguments

float velocity - "Freeze" linear velocity. If the value is lower than the engine.physics.setFrozenLinearVelocity one, it is overridden.

Ptr<BodyRigid> getBodyRigid ()

Returns an internal body rigid body that represents fracture body until it is broken.

Return value

Internal body rigid.

void setFriction (float friction)

Sets friction of the body against other surfaces.

Arguments

float friction - Friction value.

Math::vec3 getVelocity (const Math::vec3 & radius)

Returns the total linear velocity in the point specified in local coordinates.

Arguments

const Math::vec3 & radius - Radius vector starting in the body's center of mass.

Return value

Total linear velocity in the given point.

float getFrozenLinearVelocity ()

Returns the current linear velocity threshold for freezing body simulation. If body linear velocity remains lower than this threshold during the number of Frozen frames (together with angular one), it stops to be updated.

Return value

"Freeze" linear velocity.

void addWorldImpulse (const Math::Vec3 & point, const Math::vec3 & impulse)

Applies an impulse to the given point of the body, that is specified in world coordinates. Impulses immediately affect the body velocity.

Arguments

const Math::Vec3 & point - Point of the body in world coordinates.
const Math::vec3 & impulse - Amount of impulse to apply.

void addImpulse (const Math::vec3 & radius, const Math::vec3 & impulse)

Applies an impulse to the given point of the body, that is specified in local coordinates. Impulses immediately affect the body velocity.

Arguments

const Math::vec3 & radius - Radius vector starting in the body's center of mass in local coordinates. Its end is the point of impulse application.
const Math::vec3 & impulse - Amount of impulse to apply.

float getMass ()

Returns the current mass of the body.

Return value

Mass of the body.

int createCrackPieces (const Math::Vec3 & point, const Math::vec3 & normal, int num_cuts, int num_rings, float step)

Breakes the object into radial cracks combined with concentric splits. If the first concentric split is rendered further than the specified step distance, decrease the volume threshold value.

Arguments

const Math::Vec3 & point - Point of contact.
const Math::vec3 & normal - Normal of the contact point.
int num_cuts - Number of radial cuts that are represented as rays coming from the center of contact point.
int num_rings - Number of rings that form concentric splits. The number of rings that is will be actually rendered depends on the step value.
float step - Distance between concentric splits.

Return value

Positive number if the object was successfully broken; otherwise, 0.

float getFrozenAngularVelocity ()

Returns the current angular velocity threshold for freezing body simulation. If body angular velocity remains lower than this threshold during the number of Frozen frames (together with linear one), it stops to be updated.

Return value

"Freeze" angular velocity.

int getIntersectionMask ()

Returns the intersection bit mask for the body.

Return value

Integer, each bit of which is a mask.

float getRestitution ()

Returns the current restitution that determines body bouncing off the surfaces.

Return value

Restitution value.

void addTorque (const Math::vec3 & radius, const Math::vec3 & torque)

Applies a torque to the given point of the body, that is specified in local coordinates.

Arguments

const Math::vec3 & radius - Radius vector starting in the body's center of mass in local coordinates. Its end is the point of torque application.
const Math::vec3 & torque - Amount of torque to apply.

void setIntersectionMask (int mask)

Sets an intersection bit mask for the body.

Arguments

int mask - Integer, each bit of which is a mask.

float getError ()

Returns the current approximation error permissible by creating convex shape for the mesh.

Return value

Approximation error.

void setRestitution (float restitution)

Sets the restitution that determines body bouncing off the surfaces.

Arguments

float restitution - Restitution value.

Last update: 2017-07-03

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