Constraint#

struct nvConstraint#

Constraint base struct.

Public Members

nvConstraintType type#: Type of the constraint.

void *def#: Constraint definition class. (This needs to be casted)

nvBody *a#: First body.

nvBody *b#: Second body.

enum nvConstraintType#

Constraint types.

Values:

enumerator nvConstraintType_SPRING#: Spring constraint type. See nvSpring.

enumerator nvConstraintType_DISTANCEJOINT#: Distance joint constraint type. See nvDistanceJoint.

enumerator nvConstraintType_HINGEJOINT#: Hinge joint constraint type. See nvHingeJoint.

Spring Constraint#

struct nvSpring#

Spring constraint definition.

A spring constraint is a damped spring with rest length, stiffness and damping value.

Public Members

nv_float length#: Resting length of the spring.

nv_float stiffness#: Stiffness (strength) of the spring.

nv_float damping#: Damping of the spring.

nvVector2 anchor_a#: Local anchor point on body A.

nvVector2 anchor_b#: Local anchor point on body B.

nv_float target_vel#: Target relative velocity.

nv_float damping_bias#: Damping bias.

nvVector2 ra#: Anchor point on body A.

nvVector2 rb#: Anchor point on body B.

nvVector2 normal#: Normal of the constraint.

nv_float mass#: Constraint effective mass.

nv_float jc#: Accumulated constraint impulse.

nvConstraint *nvSpring_new(nvBody *a, nvBody *b, nvVector2 anchor_a, nvVector2 anchor_b, nv_float length, nv_float stiffness, nv_float damping)#

Create a new spring constraint.

Leave one of the body parameters as :code:NULL to link the body to world. Don’t forget to change the anchor point to be in world space as well.

Parameters:

a – First body
b – Second body
anchor_a – Local anchor point on body A
anchor_b – Local anchor point on body B
length – Length of the spring
stiffness – Stiffness (strength) of the spring
damping – Damping of the spring

Returns:

nvConstraint *

Distance Joint Constraint#

struct nvDistanceJoint#

Distance joint constraint definition.

A distance joint constraints the distance of two points on the two bodies to be constant. This acts like as if the two bodies are linked with a solid bar. TODO: lower upper limit

Public Members

nv_float length#: Length of the distance joint.

nvVector2 anchor_a#: Local anchor point on body A.

nvVector2 anchor_b#: Local anchor point on body B.

nvVector2 ra#: Anchor point on body A.

nvVector2 rb#: Anchor point on body B.

nvVector2 normal#: Normal of the constraint.

nv_float bias#: Constraint position correction bias.

nv_float mass#: Constraint effective mass.

nv_float jc#: Accumulated constraint impulse.

nvConstraint *nvDistanceJoint_new(nvBody *a, nvBody *b, nvVector2 anchor_a, nvVector2 anchor_b, nv_float length)#

Create a new distance joint constraint.

Leave one of the body parameters as :code:NULL to link the body to world. Don’t forget to change the anchor point to be in world space as well.

Parameters:

a – First body
b – Second body
anchor_a – Local anchor point on body A
anchor_b – Local anchor point on body B
length – Length of the joint

Returns:

nvConstraint *

Hinge Joint Constraint#

struct nvHingeJoint#

Hinge joint constraint definition.

A hinge joint, also known as revolute join, allows the bodies to rotate around a common axis. Ensuring the relative orientation of the bodies remains fixed.

Public Members

nvVector2 anchor#: Anchor point in world space.

bool enable_limits#: Enable angular limits or not.

nv_float upper_limit#: Upper angle limit.

nv_float lower_limit#: Lower angle limit.

nv_float angle#: Angle of the constraint.

nvVector2 anchor_a#: Joint anchor translated to body A.

nvVector2 anchor_b#: Joint anchor translated to body B.

nv_float upper_impulse#: Accumulated upper limit impulse.

nv_float lower_impulse#: Accumulated lower limit impulse.

nv_float reference_angle#: Reference angle for the constrain.

nv_float axial_mass#: Axial effective mass.

nvVector2 ra#: Anchor point on body A.

nvVector2 rb#: Anchor point on body B.

nvVector2 normal#: Normal of the distance constraint.

nv_float bias#: Distance constraint position correction bias.

nv_float mass#: Distance constraint effective mass.

nv_float jc#: Accumulated distance constraint impulse.

nvConstraint *nvHingeJoint_new(nvBody *a, nvBody *b, nvVector2 anchor)#

Create a new hinge joint constraint.

Leave one of the body parameters as :code:NULL to link the body to world. Don’t forget to change the anchor point to be in world space as well.

Parameters:

a – First body
b – Second body
anchor_a – Anchor point in world space.

Returns:

nvConstraint *