axmol/tests/cpp-tests/Source/ChipmunkTestBed/demo/Plink.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 "chipmunk/chipmunk.h"
#include "ChipmunkDemo.h"

static cpFloat pentagon_mass   = 0.0f;
static cpFloat pentagon_moment = 0.0f;

// Iterate over all of the bodies and reset the ones that have fallen offscreen.
static void eachBody(cpBody* body, void* unused)
{
    cpVect pos = cpBodyGetPosition(body);
    if (pos.y < -260)
    {
        cpFloat x = rand() / (cpFloat)RAND_MAX * 640 - 320;
        cpBodySetPosition(body, cpv(x, 260));
    }
}

static void update(cpSpace* space, double dt)
{
    if (ChipmunkDemoRightDown)
    {
        ChipmunkDemoRightDown = cpFalse;
        cpShape* nearest      = cpSpacePointQueryNearest(space, ChipmunkDemoMouse, 0.0, GRAB_FILTER, NULL);
        if (nearest)
        {
            cpBody* body = cpShapeGetBody(nearest);
            if (cpBodyGetType(body) == CP_BODY_TYPE_STATIC)
            {
                cpBodySetType(body, CP_BODY_TYPE_DYNAMIC);
                cpBodySetMass(body, pentagon_mass);
                cpBodySetMoment(body, pentagon_moment);
            }
            else if (cpBodyGetType(body) == CP_BODY_TYPE_DYNAMIC)
            {
                cpBodySetType(body, CP_BODY_TYPE_STATIC);
            }
        }
    }

    cpSpaceEachBody(space, &eachBody, NULL);
    cpSpaceStep(space, dt);
}

#define NUM_VERTS 5

static cpSpace* init(void)
{
    ChipmunkDemoMessageString = "Right click to make pentagons static/dynamic.";

    cpSpace* space = cpSpaceNew();
    cpSpaceSetIterations(space, 5);
    cpSpaceSetGravity(space, cpv(0, -100));

    cpBody *body, *staticBody = cpSpaceGetStaticBody(space);
    cpShape* shape;

    // Vertexes for a triangle shape.
    cpVect tris[] = {
        cpv(-15, -15),
        cpv(0, 10),
        cpv(15, -15),
    };

    // Create the static triangles.
    for (int i = 0; i < 10; i++)
    {
        for (int j = 0; j < 6; j++)
        {
            cpFloat stagger = (j % 2) * 40;
            cpVect offset   = cpv(i * 80 - 360 + stagger, j * 70 - 200);
            shape = cpSpaceAddShape(space, cpPolyShapeNew(staticBody, 3, tris, cpTransformTranslate(offset), 0.0));
            cpShapeSetElasticity(shape, 1.0f);
            cpShapeSetFriction(shape, 1.0f);
            cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);
        }
    }

    // Create vertexes for a pentagon shape.
    cpVect verts[NUM_VERTS];
    for (int i = 0; i < NUM_VERTS; i++)
    {
        cpFloat angle = -2.0f * CP_PI * i / ((cpFloat)NUM_VERTS);
        verts[i]      = cpv(10 * cos(angle), 10 * sin(angle));
    }

    pentagon_mass   = 1.0;
    pentagon_moment = cpMomentForPoly(1.0f, NUM_VERTS, verts, cpvzero, 0.0f);

    // Add lots of pentagons.
    for (int i = 0; i < 300; i++)
    {
        body      = cpSpaceAddBody(space, cpBodyNew(pentagon_mass, pentagon_moment));
        cpFloat x = rand() / (cpFloat)RAND_MAX * 640 - 320;
        cpBodySetPosition(body, cpv(x, 350));

        shape = cpSpaceAddShape(space, cpPolyShapeNew(body, NUM_VERTS, verts, cpTransformIdentity, 0.0));
        cpShapeSetElasticity(shape, 0.0f);
        cpShapeSetFriction(shape, 0.4f);
    }

    return space;
}

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

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