diff options
Diffstat (limited to 'intern')
-rw-r--r-- | intern/iksolver/extern/IK_solver.h | 186 |
1 files changed, 75 insertions, 111 deletions
diff --git a/intern/iksolver/extern/IK_solver.h b/intern/iksolver/extern/IK_solver.h index 973834f1682..78633fb0d9a 100644 --- a/intern/iksolver/extern/IK_solver.h +++ b/intern/iksolver/extern/IK_solver.h @@ -24,7 +24,8 @@ * * The Original Code is: all of this file. * - * Contributor(s): none yet. + * Original author: Laurence + * Contributor(s): Brecht * * ***** END GPL/BL DUAL LICENSE BLOCK ***** */ @@ -34,26 +35,20 @@ * $Id$ * Copyright (C) 2001 NaN Technologies B.V. * - * @author Laurence + * @author Laurence, Brecht * @mainpage IK - Blender inverse kinematics module. * * @section about About the IK module * * This module allows you to create segments and form them into - * chains. You can then define a goal point that the end of the - * chain should attempt to reach - an inverse kinematic problem. - * This module will then modify the segments in the chain in - * order to get the end of the chain as near as possible to the - * goal. This solver uses an inverse jacobian method to find - * a solution. + * tree. You can then define a goal points that the end of a given + * segment should attempt to reach - an inverse kinematic problem. + * This module will then modify the segments in the tree in order + * to get the as near as possible to the goal. This solver uses an + * inverse jacobian method to find a solution. * * @section issues Known issues with this IK solver. * - * - The current solver works with only one type of segment. These - * segments always have 3 degress of freedom (DOF). i.e. the solver - * uses all these degrees to solve the IK problem. It would be - * nice to allow the user to specify different segment types such - * as 1 DOF joints in a given plane. 2 DOF joints about given axis. * - There is currently no support for joint constraints in the * solver. This is within the realms of possibility - please ask * if this functionality is required. @@ -77,124 +72,93 @@ extern "C" { #endif -/** - * External segment structure +/** + * Typical order of calls for solving an IK problem: + * + * - create number of IK_Segment's and set their parents and transforms + * - create an IK_Solver + * - set a number of goals for the IK_Solver to solve + * - call IK_Solve + * - free the IK_Solver + * - get basis and translation changes from segments + * - free all segments */ /** - * This structure defines a single segment of an IK chain. + * IK_Segment defines a single segment of an IK tree. * - Individual segments are always defined in local coordinates. - * - The segment is assumed to be oriented in the local + * - The segment is assumed to be oriented in the local * y-direction. - * - seg_start is the start of the segment relative to the end + * - start is the start of the segment relative to the end * of the parent segment. - * - basis is a column major matrix defining the rest position - * of the bone. - * - length is the simply the length of the bone. - * - basis_change is a 3x3 matrix representing the change - * from the rest position of the segment to the solved position. - * In fact it is the transpose of this matrix because blender - * does something weird with quaternion conversion. This is - * strictly an ouput variable for returning the results of an - * an ik solve back to you. - * The local transformation specified as a column major matrix - * of a segment is then defined as. - * translate(seg_start)*basis*transpose(basis_change)*translate(0,length,0) + * - rest_basis is a column major matrix defineding the rest + * position (w.r.t. which the limits are defined), must + * be a pure rotation + * - basis is a column major matrix defining the current change + * from the rest basis, must be a pure rotation + * - length is the length of the bone. + * + * - basis_change and translation_change respectively define + * the change in rotation or translation for rotational joints + * and translational joints. basis_change is a column major 3x3 + * matrix. + * + * For rotational joints the local transformation is then defined as: + * start*rest_basis*basis*basis_change*translate(0,length,0) + * + * For translational joints: + * start*rest_basis*basis*translation_change*translate(0,length,0) */ -typedef struct IK_Segment_Extern { - float seg_start[3]; - float basis[9]; - float length; - float basis_change[9]; -} IK_Segment_Extern; - -typedef IK_Segment_Extern* IK_Segment_ExternPtr; - -/** - * External chain structure. - * This structure is filled when you call IK_LoadChain. - * The first segment in the chain is the root segment. - * The end of the last segment is the end-effector of the chain - * this is the point that tries to move to the goal in the ik - * solver. - * - num_segments is the number of segments in the array pointed - * to by the member segments. - * - chain_dof is the number of degrees of freedom of the chain - * that is the number of independent ways the chain can be changed - * to reach the goal. - * - segments points to an array of IK_Segment_Extern structs - * containing the segments of this chain. - * - intern is pointer used by the module to store information - * about the chain. Please do not touch the member in any way. - */ +typedef void IK_Segment; -typedef struct IK_Chain_Extern { - int num_segments; - int chain_dof; - IK_Segment_ExternPtr segments; - void * intern; -} IK_Chain_Extern; +enum IK_SegmentFlag { + IK_XDOF = 1, + IK_YDOF = 2, + IK_ZDOF = 4, + IK_TRANSLATIONAL = 8 +}; -typedef IK_Chain_Extern* IK_Chain_ExternPtr; +typedef enum IK_SegmentAxis { + IK_X, + IK_Y, + IK_Z +} IK_SegmentAxis; +extern IK_Segment *IK_CreateSegment(int flag); +extern void IK_FreeSegment(IK_Segment *seg); -/** - * Create a clean chain structure. - * @return A IK_Chain_Extern structure allocated on the heap. - * Do not attempt to delete or free this memory yourself please - * use the FreeChain(...) function for this. - */ +extern void IK_SetParent(IK_Segment *seg, IK_Segment *parent); +extern void IK_SetTransform(IK_Segment *seg, float start[3], float rest_basis[][3], float basis[][3], float length); +extern void IK_SetLimit(IK_Segment *seg, IK_SegmentAxis axis, float lmin, float lmax); +extern void IK_SetStiffness(IK_Segment *seg, IK_SegmentAxis axis, float stiffness); -extern IK_Chain_ExternPtr IK_CreateChain(void); +extern void IK_GetBasisChange(IK_Segment *seg, float basis_change[][3]); +extern void IK_GetTranslationChange(IK_Segment *seg, float *translation_change); /** - * Copy segment information into the chain structure. - * @param chain A chain to load the segments into. - * @param segments a ptr to an array of IK_Input_Segment_Extern structures - * @param num_segs the number of segments to load into the chain - * @return 1 if the chain was correctly loaded into the structure. - * @return 0 if an error occured loading the chain. This will normally - * occur when there is not enough memory to allocate internal chain data. - * In this case you should not use the chain structure and should call - * IK_FreeChain to free the memory associated with the chain. - */ + * An IK_Solver must be created to be able to execute the solver. + * + * An arbitray number of goals can be created, stating that a given + * end effector must have a given position or rotation. If multiple + * goals are specified, they can be weighted (range 0..1) to get + * some control over their importance. + * + * IK_Solve will execute the solver, that will run until either the + * system converges, or a maximum number of iterations is reached. + * It returns 1 if the system converged, 0 otherwise. + */ -extern int IK_LoadChain(IK_Chain_ExternPtr chain,IK_Segment_ExternPtr segments, int num_segs); +typedef void IK_Solver; -/** - * Compute the solution of an inverse kinematic problem. - * @param chain a ptr to an IK_Segment_Extern loaded with the segments - * to solve for. - * @param goal the goal of the IK problem - * @param tolerance .The distance to the solution within which the chain is deemed - * to be solved. - * @param max_iterations. The maximum number of iterations to use in solving the - * problem. - * @param max_angle_change. The maximum allowed angular change. 0.1 is a good value here. - * @param output. Results of the solution are written to the segments pointed to by output. - * Only the basis and basis_change fields are written. You must make sure that you have - * allocated enough room for the output segments. - * @return 0 if the solved chain did not reach the goal. This occurs when the - * goal was unreachable by the chain end effector. - * @return 1 if the chain reached the goal. - */ +IK_Solver *IK_CreateSolver(IK_Segment *root); +void IK_FreeSolver(IK_Solver *solver); -extern int IK_SolveChain( - IK_Chain_ExternPtr chain, - float goal[3], - float tolerance, - int max_iterations, - float max_angle_change, - IK_Segment_ExternPtr output -); - -/** - * Free a chain and all it's internal memory. - */ +void IK_SolverAddGoal(IK_Solver *solver, IK_Segment *tip, float goal[3], float weight); +void IK_SolverAddGoalOrientation(IK_Solver *solver, IK_Segment *tip, float goal[][3], float weight); -extern void IK_FreeChain(IK_Chain_ExternPtr); +int IK_Solve(IK_Solver *solver, float tolerance, int max_iterations); #ifdef __cplusplus |