axmol/tests/cpp-tests/Source/ChipmunkTestBed/demo/Springies.c

/* Copyright (c) 2007 Scott Lembcke
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <string.h>

#include "chipmunk/chipmunk.h"
#include "ChipmunkDemo.h"

static cpFloat springForce(cpConstraint* spring, cpFloat dist)
{
    cpFloat clamp = 20.0f;
    return cpfclamp(cpDampedSpringGetRestLength(spring) - dist, -clamp, clamp) * cpDampedSpringGetStiffness(spring);
}

static cpConstraint*
new_spring(cpBody* a, cpBody* b, cpVect anchorA, cpVect anchorB, cpFloat restLength, cpFloat stiff, cpFloat damp)
{
    cpConstraint* spring = cpDampedSpringNew(a, b, anchorA, anchorB, restLength, stiff, damp);
    cpDampedSpringSetSpringForceFunc(spring, springForce);

    return spring;
}

static void update(cpSpace* space, double dt)
{
    cpSpaceStep(space, dt);
}

static cpBody* add_bar(cpSpace* space, cpVect a, cpVect b, int group)
{
    cpVect center  = cpvmult(cpvadd(a, b), 1.0f / 2.0f);
    cpFloat length = cpvlength(cpvsub(b, a));
    cpFloat mass   = length / 160.0f;

    cpBody* body = cpSpaceAddBody(space, cpBodyNew(mass, mass * length * length / 12.0f));
    cpBodySetPosition(body, center);

    cpShape* shape = cpSpaceAddShape(space, cpSegmentShapeNew(body, cpvsub(a, center), cpvsub(b, center), 10.0f));
    cpShapeSetFilter(shape, cpShapeFilterNew(group, CP_ALL_CATEGORIES, CP_ALL_CATEGORIES));

    return body;
}

static cpSpace* init(void)
{
    cpSpace* space     = cpSpaceNew();
    cpBody* staticBody = cpSpaceGetStaticBody(space);

    cpBody* body1  = add_bar(space, cpv(-240, 160), cpv(-160, 80), 1);
    cpBody* body2  = add_bar(space, cpv(-160, 80), cpv(-80, 160), 1);
    cpBody* body3  = add_bar(space, cpv(0, 160), cpv(80, 0), 0);
    cpBody* body4  = add_bar(space, cpv(160, 160), cpv(240, 160), 0);
    cpBody* body5  = add_bar(space, cpv(-240, 0), cpv(-160, -80), 2);
    cpBody* body6  = add_bar(space, cpv(-160, -80), cpv(-80, 0), 2);
    cpBody* body7  = add_bar(space, cpv(-80, 0), cpv(0, 0), 2);
    cpBody* body8  = add_bar(space, cpv(0, -80), cpv(80, -80), 0);
    cpBody* body9  = add_bar(space, cpv(240, 80), cpv(160, 0), 3);
    cpBody* body10 = add_bar(space, cpv(160, 0), cpv(240, -80), 3);
    cpBody* body11 = add_bar(space, cpv(-240, -80), cpv(-160, -160), 4);
    cpBody* body12 = add_bar(space, cpv(-160, -160), cpv(-80, -160), 4);
    cpBody* body13 = add_bar(space, cpv(0, -160), cpv(80, -160), 0);
    cpBody* body14 = add_bar(space, cpv(160, -160), cpv(240, -160), 0);

    cpSpaceAddConstraint(space, cpPivotJointNew2(body1, body2, cpv(40, -40), cpv(-40, -40)));
    cpSpaceAddConstraint(space, cpPivotJointNew2(body5, body6, cpv(40, -40), cpv(-40, -40)));
    cpSpaceAddConstraint(space, cpPivotJointNew2(body6, body7, cpv(40, 40), cpv(-40, 0)));
    cpSpaceAddConstraint(space, cpPivotJointNew2(body9, body10, cpv(-40, -40), cpv(-40, 40)));
    cpSpaceAddConstraint(space, cpPivotJointNew2(body11, body12, cpv(40, -40), cpv(-40, 0)));

    cpFloat stiff = 100.0f;
    cpFloat damp  = 0.5f;
    cpSpaceAddConstraint(space, new_spring(staticBody, body1, cpv(-320, 240), cpv(-40, 40), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(staticBody, body1, cpv(-320, 80), cpv(-40, 40), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(staticBody, body1, cpv(-160, 240), cpv(-40, 40), 0.0f, stiff, damp));

    cpSpaceAddConstraint(space, new_spring(staticBody, body2, cpv(-160, 240), cpv(40, 40), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(staticBody, body2, cpv(0, 240), cpv(40, 40), 0.0f, stiff, damp));

    cpSpaceAddConstraint(space, new_spring(staticBody, body3, cpv(80, 240), cpv(-40, 80), 0.0f, stiff, damp));

    cpSpaceAddConstraint(space, new_spring(staticBody, body4, cpv(80, 240), cpv(-40, 0), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(staticBody, body4, cpv(320, 240), cpv(40, 0), 0.0f, stiff, damp));

    cpSpaceAddConstraint(space, new_spring(staticBody, body5, cpv(-320, 80), cpv(-40, 40), 0.0f, stiff, damp));

    cpSpaceAddConstraint(space, new_spring(staticBody, body9, cpv(320, 80), cpv(40, 40), 0.0f, stiff, damp));

    cpSpaceAddConstraint(space, new_spring(staticBody, body10, cpv(320, 0), cpv(40, -40), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(staticBody, body10, cpv(320, -160), cpv(40, -40), 0.0f, stiff, damp));

    cpSpaceAddConstraint(space, new_spring(staticBody, body11, cpv(-320, -160), cpv(-40, 40), 0.0f, stiff, damp));

    cpSpaceAddConstraint(space, new_spring(staticBody, body12, cpv(-240, -240), cpv(-40, 0), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(staticBody, body12, cpv(0, -240), cpv(40, 0), 0.0f, stiff, damp));

    cpSpaceAddConstraint(space, new_spring(staticBody, body13, cpv(0, -240), cpv(-40, 0), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(staticBody, body13, cpv(80, -240), cpv(40, 0), 0.0f, stiff, damp));

    cpSpaceAddConstraint(space, new_spring(staticBody, body14, cpv(80, -240), cpv(-40, 0), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(staticBody, body14, cpv(240, -240), cpv(40, 0), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(staticBody, body14, cpv(320, -160), cpv(40, 0), 0.0f, stiff, damp));

    cpSpaceAddConstraint(space, new_spring(body1, body5, cpv(40, -40), cpv(-40, 40), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body1, body6, cpv(40, -40), cpv(40, 40), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body2, body3, cpv(40, 40), cpv(-40, 80), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body3, body4, cpv(-40, 80), cpv(-40, 0), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body3, body4, cpv(40, -80), cpv(-40, 0), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body3, body7, cpv(40, -80), cpv(40, 0), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body3, body7, cpv(-40, 80), cpv(-40, 0), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body3, body8, cpv(40, -80), cpv(40, 0), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body3, body9, cpv(40, -80), cpv(-40, -40), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body4, body9, cpv(40, 0), cpv(40, 40), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body5, body11, cpv(-40, 40), cpv(-40, 40), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body5, body11, cpv(40, -40), cpv(40, -40), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body7, body8, cpv(40, 0), cpv(-40, 0), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body8, body12, cpv(-40, 0), cpv(40, 0), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body8, body13, cpv(-40, 0), cpv(-40, 0), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body8, body13, cpv(40, 0), cpv(40, 0), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body8, body14, cpv(40, 0), cpv(-40, 0), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body10, body14, cpv(40, -40), cpv(-40, 0), 0.0f, stiff, damp));
    cpSpaceAddConstraint(space, new_spring(body10, body14, cpv(40, -40), cpv(-40, 0), 0.0f, stiff, damp));

    return space;
}

static void destroy(cpSpace* space)
{
    ChipmunkDemoFreeSpaceChildren(space);
    cpSpaceFree(space);
}

ChipmunkDemo Springies = {
    "Springies", 1.0 / 60.0, init, update, ChipmunkDemoDefaultDrawImpl, destroy,
};