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// Geometric Tools, LLC
// Copyright (c) 1998-2014
// Distributed under the Boost Software License, Version 1.0.
// http://www.boost.org/LICENSE_1_0.txt
// http://www.geometrictools.com/License/Boost/LICENSE_1_0.txt
//
// File Version: 5.2.1 (2011/07/27)
#include "CollisionsMovingSpheres.h"
WM5_WINDOW_APPLICATION(CollisionsMovingSpheres);
//#define SINGLE_STEP
//----------------------------------------------------------------------------
CollisionsMovingSpheres::CollisionsMovingSpheres ()
:
WindowApplication3("SamplePhysics/CollisionsMovingSpheres", 0, 0, 640,
480, Float4(0.75f, 0.75f, 0.75f, 1.0f)),
mColliders(mSphere0, mSphere1),
mTextColor(1.0f, 1.0f, 1.0f, 1.0f)
{
#ifdef SINGLE_STEP
mSimTime = 0.01f;
mSimDelta = 0.01f;
#else
mSimTime = 0.001f;
mSimDelta = 0.001f;
#endif
mBoundingSphere.Center = Vector3f::ZERO;
mBoundingSphere.Radius = 1.0f;
}
//----------------------------------------------------------------------------
bool CollisionsMovingSpheres::OnInitialize ()
{
if (!WindowApplication3::OnInitialize())
{
return false;
}
// Set up the camera.
mCamera->SetFrustum(60.0f, GetAspectRatio(), 0.1f, 100.0f);
APoint camPosition(3.0f, 0.0f, 0.0f);
AVector camDVector(-1.0f, 0.0f, 0.0f);
AVector camUVector(0.0f, 0.0f, 1.0f);
AVector camRVector = camDVector.Cross(camUVector);
mCamera->SetFrame(camPosition, camDVector, camUVector, camRVector);
CreateScene();
// Initial update of scene.
mScene->Update();
// Initial culling of scene.
mCuller.SetCamera(mCamera);
mCuller.ComputeVisibleSet(mScene);
InitializeCameraMotion(0.01f, 0.001f);
InitializeObjectMotion(mScene);
return true;
}
//----------------------------------------------------------------------------
void CollisionsMovingSpheres::OnTerminate ()
{
mScene = 0;
mMesh0 = 0;
mMesh1 = 0;
WindowApplication3::OnTerminate();
}
//----------------------------------------------------------------------------
void CollisionsMovingSpheres::OnIdle ()
{
MeasureTime();
if (MoveCamera())
{
mCuller.ComputeVisibleSet(mScene);
}
if (MoveObject())
{
mScene->Update();
mCuller.ComputeVisibleSet(mScene);
}
#ifndef SINGLE_STEP
UpdateSpheres();
#endif
if (mRenderer->PreDraw())
{
mRenderer->ClearBuffers();
mRenderer->Draw(mCuller.GetVisibleSet());
DrawFrameRate(8, GetHeight()-8, mTextColor);
mRenderer->PostDraw();
mRenderer->DisplayColorBuffer();
}
UpdateFrameCount();
}
//----------------------------------------------------------------------------
bool CollisionsMovingSpheres::OnKeyDown (unsigned char key, int x, int y)
{
if (WindowApplication3::OnKeyDown(key, x, y))
{
return true;
}
#ifdef SINGLE_STEP
switch (key)
{
case 'g':
case 'G':
UpdateSpheres();
return true;
}
#endif
return false;
}
//----------------------------------------------------------------------------
void CollisionsMovingSpheres::CreateScene ()
{
mScene = new0 Node();
VertexFormat* vformat = VertexFormat::Create(2,
VertexFormat::AU_POSITION, VertexFormat::AT_FLOAT3, 0,
VertexFormat::AU_COLOR, VertexFormat::AT_FLOAT3, 0);
StandardMesh sm(vformat);
mSphere0.Radius = 0.1f;
mSphere1.Radius = 0.2f;
mVelocity0 = Vector3f(0.0f, -1.0f, 0.0f);
mVelocity1 = Vector3f(0.0f, 0.0f, 1.0f);
mMesh0 = sm.Sphere(16, 16, mSphere0.Radius);
mMesh1 = sm.Sphere(16, 16, mSphere1.Radius);
VertexBufferAccessor vba0(mMesh0), vba1(mMesh1);
for (int i = 0; i < vba0.GetNumVertices(); ++i)
{
vba0.Color<Float3>(0, i) = Float3(Mathf::UnitRandom(), 0.0f, 0.0f);
vba1.Color<Float3>(0, i) = Float3(0.0f, 0.0f, Mathf::UnitRandom());
}
VertexColor3Effect* effect = new0 VertexColor3Effect();
mMesh0->SetEffectInstance(effect->CreateInstance());
mMesh1->SetEffectInstance(effect->CreateInstance());
mSphere0.Center = Vector3f(0.0f, 0.75f, 0.0f);
mSphere1.Center = Vector3f(0.0f, -0.75f, 0.0f);
mMesh0->LocalTransform.SetTranslate(mSphere0.Center);
mMesh1->LocalTransform.SetTranslate(mSphere1.Center);
mScene->AttachChild(mMesh0);
mScene->AttachChild(mMesh1);
}
//----------------------------------------------------------------------------
void CollisionsMovingSpheres::UpdateSpheres ()
{
float contactTime;
Colliders::CollisionType eType = mColliders.Find(mSimTime, mVelocity0,
mVelocity1, contactTime);
WM5_UNUSED(eType);
if (contactTime < 0.0f)
{
contactTime = 0.0f;
}
if (contactTime <= mSimTime)
{
// Move the spheres through the time to make contact.
mSphere0.Center += contactTime*mVelocity0;
mSphere1.Center += contactTime*mVelocity1;
Vector3f contactPoint = mColliders.GetContactPoint();
// Compute the unit-length normals at the contact point.
Vector3f normal0 = contactPoint - mSphere0.Center;
normal0.Normalize();
Vector3f normal1 = contactPoint - mSphere1.Center;
normal1.Normalize();
// Reflect the velocities through the normals.
mVelocity0 -= 2.0f*mVelocity0.Dot(normal1)*normal1;
mVelocity1 -= 2.0f*mVelocity1.Dot(normal0)*normal0;
mSimTime -= contactTime;
}
else
{
mSphere0.Center += mSimDelta*mVelocity0;
mSphere1.Center += mSimDelta*mVelocity1;
mSimTime = mSimDelta;
}
// Keep the spheres inside the world sphere.
Vector3f diff = mSphere0.Center - mBoundingSphere.Center;
float length = diff.Normalize();
if (length >= mBoundingSphere.Radius)
{
mSphere0.Center = mBoundingSphere.Radius*diff;
mVelocity0 -= 2.0f*mVelocity0.Dot(diff)*diff;
}
diff = mSphere1.Center - mBoundingSphere.Center;
length = diff.Normalize();
if (length >= mBoundingSphere.Radius)
{
mSphere1.Center = mBoundingSphere.Radius*diff;
mVelocity1 -= 2.0f*mVelocity1.Dot(diff)*diff;
}
mMesh0->LocalTransform.SetTranslate(mSphere0.Center);
mMesh1->LocalTransform.SetTranslate(mSphere1.Center);
mScene->Update();
}
//----------------------------------------------------------------------------
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