/*----------------------------------------------------------------------------- * Some sample code for slvs.dll. We draw some geometric entities, provide * initial guesses for their positions, and then constrain them. The solver * calculates their new positions, in order to satisfy the constraints. * * Copyright 2008-2013 Jonathan Westhues. *---------------------------------------------------------------------------*/ #ifdef WIN32 # include #endif #include #include #include #include #include static Slvs_System sys; static void *CheckMalloc(size_t n) { void *r = malloc(n); if(!r) { printf("out of memory!\n"); exit(-1); } return r; } /*----------------------------------------------------------------------------- * An example of a constraint in 3d. We create a single group, with some * entities and constraints. *---------------------------------------------------------------------------*/ void Example3d() { /* This will contain a single group, which will arbitrarily number 1. */ Slvs_hGroup g = 1; /* A point, initially at (x y z) = (10 10 10) */ sys.param[sys.params++] = Slvs_MakeParam(1, g, 10.0); sys.param[sys.params++] = Slvs_MakeParam(2, g, 10.0); sys.param[sys.params++] = Slvs_MakeParam(3, g, 10.0); sys.entity[sys.entities++] = Slvs_MakePoint3d(101, g, 1, 2, 3); /* and a second point at (20 20 20) */ sys.param[sys.params++] = Slvs_MakeParam(4, g, 20.0); sys.param[sys.params++] = Slvs_MakeParam(5, g, 20.0); sys.param[sys.params++] = Slvs_MakeParam(6, g, 20.0); sys.entity[sys.entities++] = Slvs_MakePoint3d(102, g, 4, 5, 6); /* and a line segment connecting them. */ sys.entity[sys.entities++] = Slvs_MakeLineSegment(200, g, SLVS_FREE_IN_3D, 101, 102); /* The distance between the points should be 30.0 units. */ sys.constraint[sys.constraints++] = Slvs_MakeConstraint( 1, g, SLVS_C_PT_PT_DISTANCE, SLVS_FREE_IN_3D, 30.0, 101, 102, 0, 0); /* Let's tell the solver to keep the second point as close to constant * as possible, instead moving the first point. */ sys.dragged[0] = 4; sys.dragged[1] = 5; sys.dragged[2] = 6; /* Now that we have written our system, we solve. */ Slvs_Solve(&sys, g); if(sys.result == SLVS_RESULT_OKAY) { printf("okay; now at (%.3f %.3f %.3f)\n" " (%.3f %.3f %.3f)\n", sys.param[0].val, sys.param[1].val, sys.param[2].val, sys.param[3].val, sys.param[4].val, sys.param[5].val); printf("%d DOF\n", sys.dof); } else { printf("solve failed"); } } /*----------------------------------------------------------------------------- * An example of a constraint in 2d. In our first group, we create a workplane * along the reference frame's xy plane. In a second group, we create some * entities in that group and dimension them. *---------------------------------------------------------------------------*/ void Example2d() { Slvs_hGroup g; double qw, qx, qy, qz; g = 1; /* First, we create our workplane. Its origin corresponds to the origin * of our base frame (x y z) = (0 0 0) */ sys.param[sys.params++] = Slvs_MakeParam(1, g, 0.0); sys.param[sys.params++] = Slvs_MakeParam(2, g, 0.0); sys.param[sys.params++] = Slvs_MakeParam(3, g, 0.0); sys.entity[sys.entities++] = Slvs_MakePoint3d(101, g, 1, 2, 3); /* and it is parallel to the xy plane, so it has basis vectors (1 0 0) * and (0 1 0). */ Slvs_MakeQuaternion(1, 0, 0, 0, 1, 0, &qw, &qx, &qy, &qz); sys.param[sys.params++] = Slvs_MakeParam(4, g, qw); sys.param[sys.params++] = Slvs_MakeParam(5, g, qx); sys.param[sys.params++] = Slvs_MakeParam(6, g, qy); sys.param[sys.params++] = Slvs_MakeParam(7, g, qz); sys.entity[sys.entities++] = Slvs_MakeNormal3d(102, g, 4, 5, 6, 7); sys.entity[sys.entities++] = Slvs_MakeWorkplane(200, g, 101, 102); /* Now create a second group. We'll solve group 2, while leaving group 1 * constant; so the workplane that we've created will be locked down, * and the solver can't move it. */ g = 2; /* These points are represented by their coordinates (u v) within the * workplane, so they need only two parameters each. */ sys.param[sys.params++] = Slvs_MakeParam(11, g, 10.0); sys.param[sys.params++] = Slvs_MakeParam(12, g, 20.0); sys.entity[sys.entities++] = Slvs_MakePoint2d(301, g, 200, 11, 12); sys.param[sys.params++] = Slvs_MakeParam(13, g, 20.0); sys.param[sys.params++] = Slvs_MakeParam(14, g, 10.0); sys.entity[sys.entities++] = Slvs_MakePoint2d(302, g, 200, 13, 14); /* And we create a line segment with those endpoints. */ sys.entity[sys.entities++] = Slvs_MakeLineSegment(400, g, 200, 301, 302); /* Now three more points. */ sys.param[sys.params++] = Slvs_MakeParam(15, g, 100.0); sys.param[sys.params++] = Slvs_MakeParam(16, g, 120.0); sys.entity[sys.entities++] = Slvs_MakePoint2d(303, g, 200, 15, 16); sys.param[sys.params++] = Slvs_MakeParam(17, g, 120.0); sys.param[sys.params++] = Slvs_MakeParam(18, g, 110.0); sys.entity[sys.entities++] = Slvs_MakePoint2d(304, g, 200, 17, 18); sys.param[sys.params++] = Slvs_MakeParam(19, g, 115.0); sys.param[sys.params++] = Slvs_MakeParam(20, g, 115.0); sys.entity[sys.entities++] = Slvs_MakePoint2d(305, g, 200, 19, 20); /* And arc, centered at point 303, starting at point 304, ending at * point 305. */ sys.entity[sys.entities++] = Slvs_MakeArcOfCircle(401, g, 200, 102, 303, 304, 305); /* Now one more point, and a distance */ sys.param[sys.params++] = Slvs_MakeParam(21, g, 200.0); sys.param[sys.params++] = Slvs_MakeParam(22, g, 200.0); sys.entity[sys.entities++] = Slvs_MakePoint2d(306, g, 200, 21, 22); sys.param[sys.params++] = Slvs_MakeParam(23, g, 30.0); sys.entity[sys.entities++] = Slvs_MakeDistance(307, g, 200, 23); /* And a complete circle, centered at point 306 with radius equal to * distance 307. The normal is 102, the same as our workplane. */ sys.entity[sys.entities++] = Slvs_MakeCircle(402, g, 200, 306, 102, 307); /* The length of our line segment is 30.0 units. */ sys.constraint[sys.constraints++] = Slvs_MakeConstraint( 1, g, SLVS_C_PT_PT_DISTANCE, 200, 30.0, 301, 302, 0, 0); /* And the distance from our line segment to the origin is 10.0 units. */ sys.constraint[sys.constraints++] = Slvs_MakeConstraint( 2, g, SLVS_C_PT_LINE_DISTANCE, 200, 10.0, 101, 0, 400, 0); /* And the line segment is vertical. */ sys.constraint[sys.constraints++] = Slvs_MakeConstraint( 3, g, SLVS_C_VERTICAL, 200, 0.0, 0, 0, 400, 0); /* And the distance from one endpoint to the origin is 15.0 units. */ sys.constraint[sys.constraints++] = Slvs_MakeConstraint( 4, g, SLVS_C_PT_PT_DISTANCE, 200, 15.0, 301, 101, 0, 0); #if 0 /* And same for the other endpoint; so if you add this constraint then * the sketch is overconstrained and will signal an error. */ sys.constraint[sys.constraints++] = Slvs_MakeConstraint( 5, g, SLVS_C_PT_PT_DISTANCE, 200, 18.0, 302, 101, 0, 0); #endif /* 0 */ /* The arc and the circle have equal radius. */ sys.constraint[sys.constraints++] = Slvs_MakeConstraint( 6, g, SLVS_C_EQUAL_RADIUS, 200, 0.0, 0, 0, 401, 402); /* The arc has radius 17.0 units. */ sys.constraint[sys.constraints++] = Slvs_MakeConstraint( 7, g, SLVS_C_DIAMETER, 200, 17.0*2, 0, 0, 401, 0); /* If the solver fails, then ask it to report which constraints caused * the problem. */ sys.calculateFaileds = 1; /* And solve. */ Slvs_Solve(&sys, g); if(sys.result == SLVS_RESULT_OKAY) { printf("solved okay\n"); printf("line from (%.3f %.3f) to (%.3f %.3f)\n", sys.param[7].val, sys.param[8].val, sys.param[9].val, sys.param[10].val); printf("arc center (%.3f %.3f) start (%.3f %.3f) finish (%.3f %.3f)\n", sys.param[11].val, sys.param[12].val, sys.param[13].val, sys.param[14].val, sys.param[15].val, sys.param[16].val); printf("circle center (%.3f %.3f) radius %.3f\n", sys.param[17].val, sys.param[18].val, sys.param[19].val); printf("%d DOF\n", sys.dof); } else { int i; printf("solve failed: problematic constraints are:"); for(i = 0; i < sys.faileds; i++) { printf(" %d", sys.failed[i]); } printf("\n"); if(sys.result == SLVS_RESULT_INCONSISTENT) { printf("system inconsistent\n"); } else { printf("system nonconvergent\n"); } } } int main() { sys.param = CheckMalloc(50*sizeof(sys.param[0])); sys.entity = CheckMalloc(50*sizeof(sys.entity[0])); sys.constraint = CheckMalloc(50*sizeof(sys.constraint[0])); sys.failed = CheckMalloc(50*sizeof(sys.failed[0])); sys.faileds = 50; /*Example3d();*/ for(;;) { Example2d(); sys.params = sys.constraints = sys.entities = 0; break; } return 0; }