/*
* Catroid: An on-device visual programming system for Android devices
* Copyright (C) 2010-2016 The Catrobat Team
* (<http://developer.catrobat.org/credits>)
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* An additional term exception under section 7 of the GNU Affero
* General Public License, version 3, is available at
* http://developer.catrobat.org/license_additional_term
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.catrobat.catroid.test.physics.actions;
import org.catrobat.catroid.physics.PhysicsObject;
import org.catrobat.catroid.physics.PhysicsWorld;
import org.catrobat.catroid.test.physics.PhysicsBaseTest;
import org.catrobat.catroid.test.utils.TestUtils;
public class VelocityActionTest extends PhysicsBaseTest {
private static final float POSITIVE_X_TEST_VELOCITY = 10.0f;
private static final float POSITIVE_Y_TEST_VELOCITY = 10.0f;
private static final float NEGATIVE_X_TEST_VELOCITY = -10.0f;
private static final float NEGATIVE_Y_TEST_VELOCITY = -10.0f;
private static final int TEST_STEPS = 5;
private static final float TEST_STEP_DELTA_TIME = 1.0f / 60.0f;
private PhysicsObject physicsObject;
@Override
protected void setUp() throws Exception {
super.setUp();
physicsObject = physicsWorld.getPhysicsObject(sprite);
physicsObject.setType(PhysicsObject.Type.DYNAMIC);
}
public void testPositiveYVelocityWithoutGravity() {
assertEquals("Unexpected initial x-coordinate", 0, physicsObject.getX(), TestUtils.DELTA);
assertEquals("Unexpected initial y-coordinate", 0, physicsObject.getY(), TestUtils.DELTA);
physicsObject.setVelocity(0.0f, POSITIVE_Y_TEST_VELOCITY);
assertEquals("Unexpected initial x-velocity", 0, physicsObject.getVelocity().x, TestUtils.DELTA);
assertEquals("Unexpected initial y-velocity", POSITIVE_Y_TEST_VELOCITY, physicsObject.getVelocity().y,
TestUtils.DELTA);
physicsWorld.setGravity(0.0f, 0.0f);
skipWorldStabilizingSteps();
float expectedStepLength = POSITIVE_Y_TEST_VELOCITY * TEST_STEP_DELTA_TIME;
for (int i = 0; i < TEST_STEPS; i++) {
float preStepXCoordinate = physicsObject.getX();
float preStepYCoordinate = physicsObject.getY();
physicsWorld.step(TEST_STEP_DELTA_TIME);
float postStepXCoordinate = physicsObject.getX();
float postStepYCoordinate = physicsObject.getY();
assertEquals("Unexpected step length: ", expectedStepLength, postStepYCoordinate - preStepYCoordinate,
TestUtils.DELTA);
assertTrue("Post-step y-coordinate (" + postStepYCoordinate + ") is lower than pre-step y-coordinate ("
+ preStepYCoordinate + "), should be higher!", postStepYCoordinate > preStepYCoordinate);
assertTrue("Post-step x-coordinate (" + postStepXCoordinate + ") differs from pre-step x-coordinate ("
+ preStepXCoordinate + "), should be equal!", postStepXCoordinate == preStepXCoordinate);
}
}
public void testNegativeYVelocityWithoutGravity() {
assertEquals("Unexpected initial x-coordinate", 0, physicsObject.getX(), TestUtils.DELTA);
assertEquals("Unexpected initial y-coordinate", 0, physicsObject.getY(), TestUtils.DELTA);
physicsObject.setVelocity(0.0f, NEGATIVE_Y_TEST_VELOCITY);
assertEquals("Unexpected initial x-velocity", 0, physicsObject.getVelocity().x, TestUtils.DELTA);
assertEquals("Unexpected initial y-velocity", NEGATIVE_Y_TEST_VELOCITY, physicsObject.getVelocity().y,
TestUtils.DELTA);
physicsWorld.setGravity(0.0f, 0.0f);
skipWorldStabilizingSteps();
float expectedStepLength = NEGATIVE_Y_TEST_VELOCITY * TEST_STEP_DELTA_TIME;
for (int i = 0; i < TEST_STEPS; i++) {
float preStepXCoordinate = physicsObject.getX();
float preStepYCoordinate = physicsObject.getY();
physicsWorld.step(TEST_STEP_DELTA_TIME);
float postStepXCoordinate = physicsObject.getX();
float postStepYCoordinate = physicsObject.getY();
assertEquals("Unexpected step length: ", expectedStepLength, postStepYCoordinate - preStepYCoordinate,
TestUtils.DELTA);
assertTrue("Post-step y-coordinate (" + postStepYCoordinate + ") is higher than pre-step y-coordinate ("
+ preStepYCoordinate + "), should be lower!", postStepYCoordinate < preStepYCoordinate);
assertTrue("Post-step x-coordinate (" + postStepXCoordinate + ") differs from pre-step x-coordinate ("
+ preStepXCoordinate + "), should be equal!", postStepXCoordinate == preStepXCoordinate);
}
}
public void testPositiveXVelocityWithoutGravity() {
assertEquals("Unexpected initial x-coordinate", 0, physicsObject.getX(), TestUtils.DELTA);
assertEquals("Unexpected initial y-coordinate", 0, physicsObject.getY(), TestUtils.DELTA);
physicsObject.setVelocity(POSITIVE_X_TEST_VELOCITY, 0.0f);
assertEquals("Unexpected initial x-velocity", POSITIVE_X_TEST_VELOCITY, physicsObject.getVelocity().x,
TestUtils.DELTA);
assertEquals("Unexpected initial y-velocity", 0.0f, physicsObject.getVelocity().y, TestUtils.DELTA);
physicsWorld.setGravity(0.0f, 0.0f);
skipWorldStabilizingSteps();
float expectedStepLength = POSITIVE_X_TEST_VELOCITY * TEST_STEP_DELTA_TIME;
for (int i = 0; i < TEST_STEPS; i++) {
float preStepXCoordinate = physicsObject.getX();
float preStepYCoordinate = physicsObject.getY();
physicsWorld.step(TEST_STEP_DELTA_TIME);
float postStepXCoordinate = physicsObject.getX();
float postStepYCoordinate = physicsObject.getY();
assertEquals("Unexpected step length: ", expectedStepLength, postStepXCoordinate - preStepXCoordinate,
TestUtils.DELTA);
assertTrue("Post-step x-coordinate (" + postStepXCoordinate + ") is lower than pre-step x-coordinate ("
+ preStepXCoordinate + "), should be higher!", postStepXCoordinate > preStepXCoordinate);
assertTrue("Post-step Y-coordinate (" + postStepYCoordinate + ") differs from pre-step x-coordinate ("
+ preStepYCoordinate + "), should be equal!", postStepYCoordinate == preStepYCoordinate);
}
}
public void testNegativeXVelocityWithoutGravity() {
assertEquals("Unexpected initial x-coordinate", 0, physicsObject.getX(), TestUtils.DELTA);
assertEquals("Unexpected initial y-coordinate", 0, physicsObject.getY(), TestUtils.DELTA);
physicsObject.setVelocity(NEGATIVE_X_TEST_VELOCITY, 0.0f);
assertEquals("Unexpected initial x-velocity", NEGATIVE_X_TEST_VELOCITY, physicsObject.getVelocity().x,
TestUtils.DELTA);
assertEquals("Unexpected initial y-velocity", 0.0f, physicsObject.getVelocity().y, TestUtils.DELTA);
physicsWorld.setGravity(0.0f, 0.0f);
skipWorldStabilizingSteps();
float expectedStepLength = NEGATIVE_X_TEST_VELOCITY * TEST_STEP_DELTA_TIME;
for (int i = 0; i < TEST_STEPS; i++) {
float preStepXCoordinate = physicsObject.getX();
float preStepYCoordinate = physicsObject.getY();
physicsWorld.step(TEST_STEP_DELTA_TIME);
float postStepXCoordinate = physicsObject.getX();
float postStepYCoordinate = physicsObject.getY();
assertEquals("Unexpected step length: ", expectedStepLength, postStepXCoordinate - preStepXCoordinate,
TestUtils.DELTA);
assertTrue("Post-step x-coordinate (" + postStepXCoordinate + ") is higher than pre-step x-coordinate ("
+ preStepXCoordinate + "), should be lower!", postStepXCoordinate < preStepXCoordinate);
assertTrue("Post-step Y-coordinate (" + postStepYCoordinate + ") differs from pre-step x-coordinate ("
+ preStepYCoordinate + "), should be equal!", postStepYCoordinate == preStepYCoordinate);
}
}
private void skipWorldStabilizingSteps() {
for (int i = 0; i < PhysicsWorld.STABILIZING_STEPS; i++) {
physicsWorld.step(1.0f);
}
}
}