## wrong position, or I'm doing something wrong

Discuss any Chipmunk bugs here.

### wrong position, or I'm doing something wrong

Hello, I'm don't know english good, I will try to show my problem.

First part of my problem:
two bodies fall down from different position, and will stop on different coordinates, whan is wrong? Please help me...

Second part of my problem: I will try to reproduce this bug on C, with hello_chipmunk:

this is code:
Code: Select all
`#include <stdio.h>#include <stdlib.h>#include <chipmunk.h>#include <stdio.h>#include <chipmunk.h>int main(void){        // cpVect is a 2D vector and cpv() is a shortcut for initializing them.        cpVect gravity = cpv(0, -9.8);        // Create an empty space.        cpSpace *space = cpSpaceNew();        cpSpaceSetGravity(space, gravity);        // Add a static line segment shape for the ground.        // We'll make it slightly tilted so the ball will roll off.        // We attach it to space->staticBody to tell Chipmunk it shouldn't be movable.        cpShape *ground = cpSegmentShapeNew(space->staticBody, cpv(-50, 2), cpv(50, 2), 0);        cpShapeSetFriction(ground, 1);        cpSpaceAddShape(space, ground);        // Now let's make a ball that falls onto the line and rolls off.        // First we need to make a cpBody to hold the physical properties of the object.        // These include the mass, position, velocity, angle, etc. of the object.        // Then we attach collision shapes to the cpBody to give it a size and shape.        cpFloat radius = 0.1;        cpFloat mass = 1;        // The moment of inertia is like mass for rotation        // Use the cpMomentFor*() functions to help you approximate it.        cpFloat moment = cpMomentForCircle(mass, 0, radius, cpvzero);        // The cpSpaceAdd*() functions return the thing that you are adding.        // It's convenient to create and add an object in one line.        cpBody *ballBody = cpSpaceAddBody(space, cpBodyNew(mass, moment));        cpBodySetPos(ballBody, cpv(0, 3+0.22));        cpBody *ballBody2 = cpSpaceAddBody(space, cpBodyNew(mass, moment));        cpBodySetPos(ballBody2, cpv(0.2, 3+0.44));        // Now we create the collision shape for the ball.        // You can create multiple collision shapes that point to the same body.        // They will all be attached to the body and move around to follow it.        cpShape *ballShape = cpSpaceAddShape(space, cpCircleShapeNew(ballBody, radius, cpvzero));        cpShapeSetFriction(ballShape, 0.7);        cpShape *ballShape2 = cpSpaceAddShape(space, cpCircleShapeNew(ballBody2, radius, cpvzero));        cpShapeSetFriction(ballShape2, 0.7);        // Now that it's all set up, we simulate all the objects in the space by        // stepping forward through time in small increments called steps.        // It is *highly* recommended to use a fixed size time step.        cpFloat timeStep = 1.0/60.0;        for(cpFloat time = 0; time < 2; time += timeStep){                cpVect pos = cpBodyGetPos(ballBody);                cpVect vel = cpBodyGetVel(ballBody);                printf(                        "1ballBody is at (%5.2f, %5.2f). It's velocity is (%5.2f, %5.2f)\n",                        pos.x, pos.y, vel.x, vel.y                );                cpVect pos2 = cpBodyGetPos(ballBody2);                cpVect vel2 = cpBodyGetVel(ballBody2);                printf(                        "2ballBody is at (%5.2f, %5.2f). It's velocity is (%5.2f, %5.2f)\n",                        pos2.x, pos2.y, vel2.x, vel2.y                );                cpSpaceStep(space, timeStep);        }        // Clean up our objects and exit!        cpShapeFree(ballShape);        cpBodyFree(ballBody);        cpShapeFree(ground);        cpSpaceFree(space);        return 0;}`

on image same problem, what I make wrong?
Dethrail

Posts: 1
Joined: Mon Mar 24, 2014 3:44 am